E-poster 02: Basal Joint Arthroplasty Decreases Carpal Tunnel Pressure

Category: Treatment Keyword: Hand and Wrist, Diseases and Disorders N/A - Not a clinical study

● Kevin Lutsky, MD ♦ ASIF ILYAS, MD ♦ Jonas L Matzon, MD ♦ Pedro Beredjiklian, MD

Hypothesis: There is a documented association between carpal tunnel syndrome (CTS) and thumb carpometacarpal (CMC) arthritis, and these conditions commonly coexist. We have observed that patients with who have previously undergone thumb basal joint arthroplasty (BJA) rarely develop CTS in the future. Our hypothesis is that the baseline pressure within the carpal tunnel in patients with CMC arthritis is higher than the general population, and that BJA decreases the pressure within the carpal tunnel.

Methods: Fifteen patients (3 with co-existent CTS) undergoing BJA were enrolled in the study. The pressure within the carpal tunnel immediately before and after BJA was measured using a commercially available pressure monitor device (Stryker STIC, Kalamazoo, MI). In patients with concomitant CTS undergoing both BJA and carpal tunnel release (CTR), the pressure was measured after BJA but prior to release of the transverse carpal ligament.

Results: The pressure within the carpal tunnel decreased in all patients. The mean pressure prior to BJA was 18.7 mmHg and decreased to 7.7 mmHg after BJA (p < .05). Patients with concomitant CTS had a mean pre-BJA pressure of 26.7 mmHg, which decreased to 6.0 mmHg after BJA (p < .05).

Summary Points: Patients with thumb CMC arthritis have a high baseline carpal tunnel pressure, which may in part explain the association between these conditions. BJA decompresses the carpal tunnel and decreases the pressure within. In patients with concomitant CTS, BJA alone decreases the carpal tunnel pressure. Further study is warranted on the need for discrete release of the transverse carpal ligament in patients undergoing BJA who have concomitant CTS.

References:

● Consulting Fee: Synthes (Lutsky)

♦ No relevant financial relationships to disclose

E-poster 03: axonal fusion in human digital nerves

Category: Treatment, Surgical Technique Keyword: Hand and Wrist, Nerve Level 3 Evidence

♦ Ratnam Nookala, MBBS ♦ Wesley P Thayer, MD, PhD

Hypothesis: We hypothesize that Polyethylene glycol (PEG) therapy enhances axonal injury recovery as demonstrated by electrophysiology and retrograde labelling in rats. We propose that this rapid nerve recovery will translate to clinical setting.

Methods: To validate that PEG treatment results in early return of axonal continuity and function, retrograde tracing was performed in rats by exposing cut end of the repaired sciatic nerves to fast-blue tracer[1-4]. Experimental animals received PEG; control animals did not receive PEG. L2-L4 spinal cord segments were sectioned and fluorescent-labeled cells examined under microscope. Separately, in an IRB approved study, patients with traumatic lacerations involving digital nerves were treated with PEG after standard microsurgical neurorrhaphy. Sensory assessment was performed post operatively using static two-point discrimination (2PD) and Semmes-Weinstein monofilament (SWM) testing. The level of sensory function was determined by Medical Research Council Classification (MRCC) for Sensory Recovery-Scale. In a separate IRB exempt study, 2PD and MRCC score of 6 patients treated with standard microsurgical neurorrhaphy was collected. This data was compared with that of patients with PEG fused nerves.

Results: PEG greatly improved neuronal labelling by retrograde tracers uptake in experimental vs negative control rats. The statistical analysis on retrograde labelled cells was performed by paired student t-test for PEG vs positive and negative controls (P value for negative control vs PEG group of 0.0363). PEG therapy has shown to improve functional outcomes and speed of nerve recovery in clinical setting. PEG was performed in four digital nerves in two patients. At 1wk, 10 mm 2PD was observed. SWM testing was 4.31. These results correlate with MRCC score of S3+ at 1wk after injury. Statistical analysis was performed between the PEG vs No peg nerve repairs using Mann Whitney Test. There was statistical significance between the PEG fused nerves and nerves fused with standard microsurgical repair without PEG (P values 0.0251, 0.0109, 0.0094 at 1, 4 and 8 weeks respectively).

Summary Points: • In animals models Polyethylene glycol (PEG) therapy has shown to improve both physiologic and behavioral outcomes after nerve severance as evidenced by retrograde labelling. This is believed to be due to fusion of a fraction of the proximal axons to the distal axon stumps. • PEG therapy improves early functional outcomes after digital nerve injury in humans. • If this technique can successfully rescue distal axons after more proximal mixed-nerve injuries, we may be able to dramatically improve long-term recovery for a group of patients who typically have poor outcomes.

References: Reference 1: Badia, J., et al., Topographical distribution of motor fascicles in the sciatic-tibial nerve of the rat. Muscle Nerve, 2010. 42(2): p. 192-201. Reference 2: Haase, P. and J.N. Payne, Comparison of the efficiencies of true blue and diamidino yellow as retrograde tracers in the peripheral motor system. J Neurosci Methods, 1990. 35(2): p. 175-83. Reference 3: Hayashi, A., et al., Retrograde labeling in peripheral nerve research: it is not all black and white. J Reconstr Microsurg, 2007. 23(7): p. 381-9. Reference 4: Novikova, L., L. Novikov, and J.O. Kellerth, Persistent neuronal labeling by retrograde fluorescent tracers: a comparison between Fast Blue, Fluoro-Gold and various dextran conjugates. J Neurosci Methods, 1997. 74(1): p. 9-15.

Fluorescent retrograde labeled spinal motor neurons

Figure 1: Graph showing no. of spinal motor neurons in controls vs PEG. The fluorescent labeled cells are counted in every 10th section of L2-L4 segments of the spinal cord. The PEG therapy groups demonstrated statistical significance (P<0.005) compared with negative control group. n=3 in each group.

Post Op functional recovery in PEG vs Control patients

Figure 2: Recovery after PEG fusion of digital nerves in patient 1 and 2 at post op follow ups. PEG fusion significantly improves recovery and functional outcomes as early as 1 week.

♦ No relevant financial relationships to disclose

E-poster 04: PROSTHETIC REPLACEMENT OF THE WRIST

Category: Treatment Keyword: Hand and Wrist Level 3 Evidence

♦ Sandra P. Fanner, MD

Hypothesis: Current indications for total wrist arthroplasty include patients with symptomatic end stage post- traumatic wrist arthritis, rheumatoid arthritis, PRC failures and Kienböck disease. Arthroplasty may have advantage over arthrodesis because of the ability to retain motion. The purpose of this study was to evaluate the mid-term clinical outcomes and complications of 2 different devices : Universal 2 (23 implants) and Re-motion (10 implants) total wrist arthroplasty.

Methods: We report the results of a retrospective review of 29 total wrist prostheses implanted in 27 patients (2 bilateral). Patient’s satisfaction, the Visual Analog Pain score, ROM and the Disabilities of the Arm, Shoulder, and Hand questionnaires were evaluated. We reviewed radiographic parameters (stress shielding at radial component, osteolysis around the screws, radiolucency lines, bone resorption, implant loosening) and complications.

Results: At a mean follow-up of 58 months, the DASH score was 36 (68 preop.). Mean pain scores improved from 8.75 to 1.6. The mean wrist flexion-extension arc was 75° (30° preop.). Radiographs revealed radiological evidence of aseptic implant loosening (subsidence of the carpal component) in 5 cases. Early complications occurred in one patient only, consisting in marginal skin necrosis. Late complications that led to secondary surgery occurred in 5 of 33 patients: in 2 cases a revision of the distal carpal component had to be performed, 2 cases were converted to a wrist Swanson silicon spacer, one resection of the ulnar head for pain on the ulnar side of the wrist.

Summary Points: Total wrist arthroplasty performed for pancarpal arthritis represents a good alternative to arthrodesis; it is more appealing for the patient as it provides pain relief and retains joint motion. Recent anatomic prosthetic models can yield successful outcomes with low mid-term failure rates; is mandatory do not forget that it is a complex surgery, with high cost and the success of which depends on the correct indication.

References: Reference 1: Herzberg G. et al “Remotion” Total Wrist Arthroplasty: Preliminary Results of a Prospective International Multicenter Study of 215 Cases J Wrist Surg. 2012 Aug;1(1):17-22. Reference 2: Anderson M., Adams BD Total wrist arthroplasty. Hand Clin 2005, 21 : 621-630 Reference 3: Strunk S. Bracker W. Wrist joint arthroplasty : Results after 41 prostheses. Handchir Mikrochir Plast Chir 2009 41 : 141-147 Reference 4: Angel Ferreres, MD et al. Universal Total Wrist Arthroplasty: Midterm Follow-Up Study J Hand Surg 2011;36A:967–973. Reference 5: Kemal R, Weiss AP ”Total wrist arthroplasy for the patient with non-rheumatoid arthritis” Reference 6: Adams BD Wrist arthroplasty:partial and total. Hand Clin 2013

Figure 1

Figure 2

♦ No relevant financial relationships to disclose

E-poster 05: Long-term Outcomes of Primary Repair of Chronic Thumb Ulnar Collateral Ligament Injuries

Category: Evaluation/Diagnosis, Treatment, Surgical Technique, Historical Information, Prognosis/Outcomes Keyword: Hand and Wrist, Diseases and Disorders Level 4 Evidence

♦ Thomas J Christensen, MD

Hypothesis: Chronic thumb ulnar collateral ligament (UCL) injuries are common are typically require surgical intervention. A wide variety of surgical treatments are recommended, the majority of which include reconstruction rather than repair. The purpose of this study is to evaluate the long-term outcomes of ligamentous repair rather than reconstruction for chronic injuries.

Methods: A retrospective chart review was conducted for patients undergoing repair of a chronic (greater than six weeks) UCL prior at least 15 years prior. Patients either returned to clinic for questionnaire analysis, physical examination, and radiographs, or if unable, performed only a mail-in questionnaire. Questionnaires included the DASH, VAS pain scale, and a study specific questionnaire. Radiographs were evaluated for joint subluxation and osteoarthritis.

Results: Twelve of 21 (57%) of living patients were available for long-term, greater than 15-year followup (average 24.5 years, range 16.9-35.6). Nine of the 12 (75%) were available for questionnaire, clinical, and radiographic follow-up; whereas, 3 of 12 (25%) were available for questionnaire follow-up by mail correspondence only. Seven of the 8 patients undergoing radiographs (88%) had some degree of osteoarthritis. Increased age at the time of injury and higher DASH scores were correlated with increased grades of the thumb MCP osteoarthritis (Table 1). Delay to treatment and VAS pain scores had no correlation with radiographic findings.

Summary Points: - Repair of a chronic UCL injury is feasible available local tissue with or without joint stabilization - This approach appears to be a reasonable alternative to ligament reconstruction - it results in durable long-term outcomes despite some patients having residual instability and the majority of patients progressing to osteoarthritis at an average of 24.5 year follow-up.

References: Reference 1: Heyman P. Injuries to the ulnar collateral ligament of the thumb metacarpophalangeal joint. J Am Acad Orthop Surg. 1997;5:224-229. Reference 2: Lee A, Carlson M. Thumb Metacarpophalangeal Joint Collateral Ligament Injury Management. Hand Clin. 2012;28:361-370. Reference 3: Merrell G, Slade J. Green's Operative Hand Surgery. Philadelphia: Churchill Livingston; 2011. Reference 4: Chuter G, Muwanga C, Irwin L. Ulnar collateral ligament injuries of the thumb: 10 years of surgical experience. Injury. 2009;40:652-656. Reference 5: Bean C, Tencer A, Trumble T. The effect of thumb metacarpophalangeal ulnar collateral ligament attachment site on joint range of motion: an in vitro study. J Hand Surg Am. 1999;24:283-287. Reference 6: Carlson M, Warner K, Meyers K, et al. Mechanics of an Anatomical Reconstruction for the Thumb Metacarpophalangeal Collateral Ligaments. J Hand Surg. 2013;38A:117-123. Reference 7: Carlson M, Warner K, Meyers K, et al. Anatomy of the Thumb Metacarpophalangeal Ulnar and Radial Collateral Ligaments. J Hand Surg. 2012;37A:2012-2026. Reference 8: Harley B, Werner F, JK G. A Biomechanical Modeling of Injury, Repair, and Rehabilitation of Ulnar Collateral Ligament Injuries of the Thumb. J Hand Surg 2004;29A:915- 920. Reference 9: Minami A, An K, Cooney WP 3rd, et al. Ligament stability of the metacarpophalangeal joint: a biomechanical study. J Hand Surg Am. 1985;10:255-260. Reference 10: Ryu J, Fagan R. Arthroscopic treatment of acute complete thumb metacarpophalangeal ulnar collateral ligament tears. J Hand Surg Am. 1995;20:1037-1042.

Table 1: Spearman Correlation Coefficient data for patient clinical outcomes versus radiographic outcomes. Values in bold indicate a significant correlation.

Xray AP angle Xray AP translation Xray DJD Age at injury 0.62 0.56 0.59 Delay to treatment -0.03 0.04 -0.12 DASH 0.40 0.28 0.76 VAS 0.46 0.08 -0.24 Clinical Instability 0.70 0.45 0.16 Total MCP Motion -0.31 -0.63 -0.25 Grip (% contralateral) -0.59 -0.56 -0.25

♦ No relevant financial relationships to disclose

E-poster 06: Results of Arthroscopic Reduction Association of the Scapholunate Joint

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist Level 4 Evidence

♦ Steven M Koehler, MD ♦ Sara M Guerra, MESc, MD ● Michael R. Hausman, MD

Hypothesis: There are multiple surgical methods used to treat scapholunate interosseous ligament tears, however none have been shown to be more superior to others. The reduction association scapholunate technique was described as an open technique that creates a fibrous non-union between the scaphoid and lunate, but a more recent alternative technique includes the use of an arthroscope for fixation (1,2). We hypothesize that Arthroscopic Reduction Association of the Scaphoid and Lunate (ARASL) is an optimal technique for scapholunate ligament injuries that decreases wrist pain and improves function.

Methods: 31 patients with scapholunate injuries who had undergone ARASL by the senior author where included. Post-operative pain score, DASH, range of motion (ROM), grip strength and radiographic parameters were calculated. Statistical significance was calculated using a two- tailed t-test.

Results: The average follow-up time was 3 years. Postoperative radiographs revealed a noticeable reduction in average SL angle, SL joint diastasis and carpal height ratio. Postoperative average VAS was 2.7 and average DASH score was 19.52. The average postoperative grip strength difference was 3.72kg less in the operative wrist compared to the nonoperative wrist. The average arc of postoperative range of motion was 97.8o. There were 13 complications (42%). 10 patients had SL joint widening, 4 patients had windshield-wipering of the hardware, and 20 patients had carpal collapse. 2 patients required hardware removal, 2 patients underwent revision. ARASL and 2 patients had a PRC. Overall survival was 81% of the index surgery. In the patients without SLAC wrist, the SL angle, SL joint diastasis and carpal height ratio were further improved. The DASH score was significantly better. There were 3 complications (21%), all of which were SL gap widening. No patient required additional surgery and postoperative survivorship was 100%.

Summary Points: • Patients undergoing ARASL maintain a high average arc of wrist motion. • Overall survival of the procedure is very promising. • Patients with SLAC wrist had worse outcomes, worse index procedure survival, the majority of complications and all of the revision surgeries. • Patients without SLAC had better DASH scores, improved SL angle, less carpal collapse, better ROM, fewer complications and no revisions. • The ARASL technique is a viable surgical option for well-selected patients with scapholunate injuries. • Perfect technique is imperative for a chance at success for this procedure.

References: Reference 1: Rossenwasser MP, Strauch RJ, Miyasaka KC. The RASL procedure: reduction association of the scaphoid and lunate using the Herbert screw. Techniques in Hand and Upper Extremity Surgery 1997 1(4):263-272. Reference 2: 2. Aviles AJ, Lee SK, Hausman MR. Arthroscopic reduction-association of the scapholunate. Arthroscopy. 2007 Jan;23(1):105.e1-e5.

Table 1 No SLAC! SLAC! P values! Total patients! 14 17 Males! 10 11 Average Age! 52.86 63.35 0.03 ***! Average gap preop! 6 5.41 0.8 Average gap postop! 3 4.71 0.04 ***! Average decrease in gap! 3 0.71 0.92 Average DASH postop! 16.45 19.13 0.94 Average VAS postop! 5 2.6 0.95 Average Grip! 10 5.99 0.02 ***! Average ROM arc! 110.71 87.12 0.078 Average preop SL angle! 69.29 75.6 0.41 Average postop SL angle! 52.5 65.53 0.46 Average CL angle postop! 15.5 12.1 0.37 Average carpal height preop! 1.56 1.47 0.11 ***! Average carpal height postop! 1.5 1.38 0.006 ***! Number of carpal collpase! 6 14 0.02 ***! Number of complications! 3 9 0.39 ***! Windshield-wipering! 0 4 0.05 ***! Gap widening! 3 7 0.26 Revision surgeries! 0 6 0.01 ***!

● Consulting Fee: Stryker, Checkpoint Surgical (Hausman) ● Ownership Interest: Checkpoint Surgical (equity) NDI Medical (equity) (Hausman)

♦ No relevant financial relationships to disclose

E-poster 07: Discrepancies Between Meeting Abstracts and Subsequent Full Text Publications in Hand Surgery

Category: Historical Information, Prognosis/Outcomes Keyword: General Principles, Practice Management N/A - Not a clinical study

♦ Todd A Theman, MD

Hypothesis: Research abstracts presented during the proceedings of an annual meeting are often cited and can influence practice, yet it is unknown how often the results or conclusions of studies presented at hand surgery meetings change when compared to the subsequent publication. The objective of this study was to quantify the differences between abstracts presented during the annual meeting of the American Society for Surgery of the Hand (ASSH) and the resulting manuscripts.

Methods: We retrospectively reviewed every abstract presented at the ASSH annual meeting from 2000- 2010. We searched the PubMed database for matching publications and compared authorship, country of origin, hypothesis, methods, changes in study groups or populations, and results and conclusions. Authorship changes consist of an addition or deletion of an author, not a change in the order. Changes to a result or conclusion were counted if there was any double-digit (or larger) change for a quantitative outcome, any change in the direction of an outcome (positive to negative or equivocal or vice versa), or in cases where the abstract and subsequent publication had the same number of patients and same follow up, there was any change in complications, correlation, satisfaction rate, or success/failure rate.

Results: Of the 798 total abstracts, we analyzed the 719 involving the hand, wrist, and brachial plexus. 56 different journals published 393 of the abstracts for a 49.2% publication rate. The most common journal was the Journal of Hand Surgery American (212 publications, 54%), followed by The Journal of Bone and Joint Surgery (51, 13%), Journal of Hand Therapy (11, 2.8%), Plastic and Reconstructive Surgery (11, 2.8%) and the Journal of Hand Surgery European volume (10, 2.5%). Mean time to publication was 18.2 months with a median of 13.8 and maximum of 122 months. 36 (4.5%) of the full-text studies were published prior to or the same month the meeting took place. There were, on average, 3.6 authors per abstract. 69.6% of the abstracts were U.S. origin only, 26.8% non-U.S. only, and 3.7% a U.S./non-U.S. combination. There were inconsistencies between the results or conclusions in 14.2% of papers compared to the abstract presented at the meeting. 8.9% of papers were published with fewer subjects. Authorships changes were found in 53.7% of publications.

Summary Points: • Abstracts represent preliminary investigations and major and minor changes do occur prior to subsequent publication. • Caution should be exercised in referencing abstracts or altering clinical practice based on their content.

References: Reference 1: Bhandari M, Devereaux PJ, Guyatt GH, et al. An observational study of orthopaedic abstracts and subsequent full-text publications. J Bone Joint Surg Am. 2002;84-A(4):615-21 Reference 2: Hamlet WP, Fletcher A, Meals RA. Publication patterns of papers presented at the Annual Meeting of The American Academy of Orthopaedic Surgeons. J Bone Joint Surg Am. 1997;79(8):1138-43 Reference 3: Gavazza JB, Foulkes GD, Meals RA. Publication pattern of papers presented at the American Society for Surgery of the Hand annual meeting. J Hand Surg Am. 1996;21(5):742-5 Reference 4: Scherer RW, Dickersin K, Langenberg P. Full publication of results initially presented in abstracts. A meta-analysis. JAMA. 1994;272(2):158-62 Reference 5: Weber EJ, Callaham ML, Wears RL, et al. Unpublished research from a medical specialty meeting: why investigators fail to publish. JAMA. 1998;280(3):257-9 Reference 6: Jasko JJ, Wood JH, Schwartz HS. Publication rates of abstracts presented at annual musculoskeletal tumor society meetings. Clinical orthopaedics and related research. 2003(415):98-103 Reference 7: Murrey DB, Wright RW, Seiler JG, 3rd, et al. Publication rates of abstracts presented at the 1993 annual Academy meeting. Clin Orthop Relat Res. 1999(359):247-53 Reference 8: Slobogean GP, Verma A, Giustini D, et al. MEDLINE, EMBASE, and Cochrane index most primary studies but not abstracts included in orthopedic meta-analyses. J Clin Epidemiol. 2009;62(12):1261-7

Fig. 1. Percent of abstracts from ASSH meetings for years 2000-2010 published as a function of time since presentation.

Table 1. Examples of substantive changes in results or conclusions from abstract to publication

2000 1. In a joint contracture study, the 2006 Outcome predictors following distal radius complication rate changed from 22% to 35% fracture changed

2. In a wrist study, the paper had four fewer patients, three fewer operative revisions, and markedly increased satisfaction rate 2001 In a cadaver study of scaphoid fracture 2007 1. An implant study found one less fixation, biomechanical results differed by a subluxation, better implant survival and factor up to seven-fold patient satisfaction with the same patient population

2. Abstract found a large dysesthesia rate after regional block while paper cites no difference 2002 In a wrist arthroscopy study, despite having 2008 1. Use of a surgical procedure had a nearly 100 more patients in the paper, “lasting positive result” in the abstract and there were two fewer complications was “disappointing” and “cannot be reported; the complication rate was less advocated” in the paper than half that reported in the abstract 2. Dissatisfaction rate increased from 44% in the abstract to 72% in the paper 2003 1. Four of five patient groups eliminated 2009 In an imaging study, despite same patient from final paper on flexor tendon repair group, the abstract and paper report up to 4-fold difference in sensitivity, specificity, 2. An abstract on Kienbock’s disease and accuracy. presented over one year after publication of the manuscript had two fewer patients (of 20) in their analysis, though the conclusions were the same. 2004 1. One more non-union reported in the paper 2010 The predictive value of a distal radioulnar despite identical follow up period joint (DRUJ) stepoff for radioulnar ligament tear decreased from 27-fold to 5- fold, 2. Despite identical patient group and abstract to paper, in a study of DRUJ follow-up in a study of scaphoid fractures, instability in distal radius fractures time to union and return to work both increased nearly 25% in the paper

3. Abstract found arthroscopy superior to open approach, paper stated equivalency 2005 1. The only “poor” outcome in a distal radius fracture paper was eliminated in the paper

2. Longer term follow up found no difference in a drug injection study, which was suggested in the abstract

♦ No relevant financial relationships to disclose

E-poster 08: Dorsal Ulnar Sulcus of the Distal Radius

Category: Evaluation/Diagnosis, Anatomy Keyword: Hand and Wrist N/A - Not a clinical study

♦ Johnathan J Whitaker, DO ♦ Howard Roth, MD ♦ David A Fuller, MD ♦ Vishal Khatri, MD ♦ Veniamin Barshay, MD

Hypothesis: Introduction: Dorsal extensor tendon rupture is a known complication of volar locking plate fixation for treatment of distal radius fractures. A detailed understanding of the dorsal anatomy of the distal radius may help explain why this occurs and may reduce future events. The purpose of this study is to describe a dorsal ulnar sulcus of the distal radius that can hide dorsal screw penetration and thus act as a blindspot to standard oblique radiographic images.

Methods: After obtaining approval from our Institutional Review Board and informed consent from patients, Fifty-four consecutive magnetic resonance images of different wrists were analyzed. Using the axial cut with the maximum sulcus depth, a line was drawn from the apex of Lister’s tubercle to the dorsal ulnar corner of the radius. A perpendicular line was then drawn from this line to the deepest point in the sulcus. This measurement was recorded as sulcus depth.

Results: A sulcus was found in 96% (52/54) of individuals which had an average depth of 1.4mm. The sulcus measured greater or equal to 2mm in 15% (8/54) of the wrists studied. There was no significant difference between gender or extremity side regarding sulcus depth.

Conclusion: The dorsal ulnar blindspot is a clinically relevant sulcus on the dorsum of the distal radius. This region demonstrated variable depth in our study and is not easily quantified using standard radiographs. Therefore caution should be taken when placing volar screws to prevent dorsal cortex penetration and subsequent extensor tendon injury.

Axial diagram & MRI of the distal radius demonstrating the method of sulcus measurement. First, a line was drawn from the apex of Lister's tubercle (L) to the dorsal ulnar corner of the radius. Second, a measurement was made perpendicular from the first line to the deepest point (D) in the sulcus.The axial T2 MRI image displays a dorsal

♦ No relevant financial relationships to disclose E-poster 09: The risk factors associated with subluxation of the distal interphalangeal joint in mallet fracture

Category: Evaluation/Diagnosis Keyword: Hand and Wrist Level 3 Evidence

♦ Jae Kwang Kim, MD, PhD

Hypothesis: Surgical fixation is recommended when a mallet fracture involves more than 1/3 of the articular surface of the distal phalanx. This recommendation originates from the idea that involvement of more than 1/3 of the base of the distal phalanx causes subluxation of the distal interphalangeal (DIP) joint. The purpose of this study was to confirm that the involvement of more than 1/3 of the articular surface of the distal phalanx causes subluxation of the DIP joint and to identify the risk factors of DIP joint subluxation in mallet fracture.

Methods: Eighty-six fingers of eight-five patients with a mallet fracture involving more than 1/3 of the articular surface of the distal phalanx were enrolled in this study. Patients were allocated according to the presence of subluxation of the DIP joint to a no subluxation group or a subluxation group. These two groups were compared with respect to age, sex, fracture size, fracture displacement, time to finger immobilizer application, and initial extension lag of the DIP joint. Backward stepwise multiple logistic regression analysis was performed to identify the risk factors of DIP joint subluxation, and receiver operating curve analysis was used to calculate optimal cut-off point of risk factors.

Results: The two study groups each contained forty-three patients. A significant intergroup difference was found for fracture size and time to finger immobilizer application, but no significant difference was observed for other parameters. The risk factors of DIP joint subluxation were fracture size and time to finger immobilizer application. The optimal cut-off values for the development of DIP joint subluxation were 48% for fracture size and 12.5 days for time to finger immobilizer application.

Summary Points: Just a half of our patients with a mallet fracture and involvement of more than 1/3 of the articular surface of the distal phalanx showed subluxation of the DIP joint. The risk factors associated with subluxation of the DIP joint were fracture size and time to finger immobilizer application.

♦ No relevant financial relationships to disclose

E-poster 10: MRI evaluation in the capitulum of humerus with osteochondritis dissecans(COCD)

Category: Evaluation/Diagnosis Keyword: Elbow and Forearm Level 3 Evidence

♦ Toshiro Itsubo, MD ♦ Hiroshi Yamazaki, MD ♦ Narumichi Murakami, MD,PhD ♦ Masanori HAYASHI, MD ♦ Shigeharu UCHIYAMA, MD ♦ Hiroyuki KATO, MD

Hypothesis: The new MRI classification is evaluable with stability of COCD preoperatively.

Methods: Fifty-two COCD lesions were preoperatively evaluated by T2-weighted MRI and classified into 5 stages: Stage 1: normally shaped capitellum with several spotted areas of high signal intensity that was lower than that of cartilage; Stage 2: as Stage 1, but with several spotted areas of higher intensity than that of cartilage; Stage 3: as Stage 2, but both with discontinuity and noncircularity of the chondral surface signal of the capitellum. No high signal interface is apparent; Stage 4: the lesion was separated by a high intensity line in comparison with cartilage; and Stage 5: the capitellar lesion was displaced from the floor or defect of the capitellar lesion was noted(Table). We compared our MRI staging results with intraoperative ICRS classification for lesion stability of each patient. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were all determined for fragment instability. Intra- and inter- rater correlations for our MRI staging were calculated among three examiners.

Results: Preoperative MRI grading correctly matched ICRS classification in 49 of 52 patients (94%) with a sensitivity of 100% and a specificity of 80%. The PPV and NPV were 93% and 100%, respectively, for diagnosing lesion instability. Intra-rater reliability for MRI staging was high at ICC1, 1: 0.86 and ICC1, 2: 0.90, as was inter-rater reliability at ICC2, 1: 0.82 and ICC2, 3: 0.88.

Summary Points: Our MRI staging provides accurate and reliable evidence for estimating ICRS classification and instability of COCD and is useful to decide appropriate treatment.

References:

♦ No relevant financial relationships to disclose

E-poster 11: Dual Tightrope Suspensionplasty for Thumb Basilar Joint Arthritis: A Case Series

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist Level 4 Evidence

● Sanjeev Kakar, MD, MBA

Hypothesis: Dual tightrope suspensionplasty is a safe and effective treatment for basilar thumb arthritis.

Methods: A retrospective review was conducted for patients undergoing trapeziectomy and dual tightrope suspensionplasty with at least 1 year of follow up. Strength, range of motion, and degree of 1st metacarpal subsidence on radiographs, were collected both preoperatively and at latest follow up. All patients completed Disability of Arm, Shoulder and Hand (DASH) survey, Patient Rated Wrist Evaluation (PRWE), and the Michigan Hand Outcome Questionnaire (MHQ) at their latest follow up.

Results: 11 patients (12 thumbs) with a mean follow up of 18 months (13-26) were identified. The group consisted of 10 women and 1 man with a mean age of 60 years (43-73). All 12 had abductor pollicis longus and flexor carpi radialis imbrication at the time of suspensionplasty (Figure 1). At latest follow up the mean DASH score was 19 (0-60), MHQ score was 75 (34-97), and PRWE score was 21 (0-71). 10 out of 11 patients reported being satisfied with their overall pain level. 9 out of 11 patients were satisfied with the overall function of their hand. Matched pairs analysis of preoperative and postoperative measurements was performed. Strength and range-of-motion data is presented in table 1. Radiographs demonstrated maintenance of 1st metacarpal height and there were no cases of overtightening or impingement between the thumb and index finger metacarpal bases. There were no fractures of the index finger metacarpal within this patient cohort. Three patients had temporary dysesthesias of the dorsal branch of the radial nerve that were managed nonoperatively. One patient developed chronic regional pain syndrome.

Summary Points: •18 months after dual tightrope suspensionplasty patients were satisfied with both pain and function in 10 out of 12 cases •Grip, appositional pinch, and oppositional pinch strength significantly improved •There were no cases of fracture or impingement of the 1st and 2nd metacarpal bases with this new technique.

References: Reference 1: Yao J, Song Y. Suture-button suspensionplasty for thumb carpometacarpal arthritis: a minimum 2-year follow-up. J. Hand Surg. 2013;38(6):1161–1165. doi:10.1016/j.jhsa.2013.02.040. Reference 2: Cox CA, Zlotolow DA, Yao J. Suture button suspensionplasty after arthroscopic hemitrapeziectomy for treatment of thumb carpometacarpal arthritis. Arthrosc. J. Arthrosc. Relat. Surg. Off. Publ. Arthrosc. Assoc. North Am. Int. Arthrosc. Assoc. 2010;26(10):1395–1403. doi:10.1016/j.arthro.2010.07.006. Reference 3: Stussi JD, Dap F, Merle M. [A retrospective study of 69 primary rhizarthrosis surgically treated by total trapeziectomy followed in 34 cases by interpositional tendinoplasty and in 35 cases by suspensioplasty]. Chir. Main. 2000;19(2):116–127.

● Consulting Fee: Arthrex Inc, Skeletal Dynamics (Kakar ● Contracted Research: Arthrex Inc (Kakar) E-poster 12: A Comparative Study of the Effects of Muscle-derived stem cell seeded Fibrin Gel and Collagen Gel Interposition in an in vitro Tendon Healing Model

Category: Basic Science Keyword: Hand and Wrist N/A - Not a clinical study

♦ Yasuhiro Ozasa, MD,PhD ♦ Chunfeng Zhao, MD ♦ Anne Gingery, PhD ♦ Kai-Nan An, PhD ♦ Andrew R Thoreson, MS ♦ Peter Amadio, MD

Hypothesis: Interposition of a muscle-derived stem cell(MDSC)-seeded fibrin gel patch supplemented with growth and differentiation factor-5(GDF-5) at the repair site would result in higher tendon healing strength than a repair using a collagen gel patch in an in vitro tissue culture model.

Methods: MDSCs were isolated by a modified preplate technique(1). Sixty-four canine flexor digitorum profundus tendons were assigned into 4 groups: 1) repaired tendon without gel patch interposition (no cell group), 2) with fibrin gel patch interposition alone (FG group), 3) with GDF- 5 treated MDSC seeded collagen gel patch interposition (CG-MG group) and 4) with GDF-5 treated MDSC seeded fibrin gel patch interposition (FG-MG group). After culturing for 2 or 4 weeks, the maximum failure strength and stiffness of the healing tendons were measured by using a custom-designed micro tester(2). In order to evaluate cell source, MDSCs were labeled with cell labeling solution before seeding in the gel patch. The section was observed with a laser scanning confocal microscope. The results of the maximum failure strength and stiffness were analyzed by one-way factorial analysis of variance. The significance level was set to P<0.05 in all cases.

Results: The maximum failure strength of the healing tendon in the FG-MG group was significantly (P< 0.05) higher than that of the no cell, FG and CG-MG groups at both 2 and 4 weeks(Fig.1). The stiffness of the healing tendons in the FG-MG group was significantly (P< 0.05) higher than that of the no cell, FG and CG-MG groups at 2 weeks and no cell and FG groups at 4 weeks. Implanted cells became incorporated into the original tendon in both cell-seeded groups(Fig.2).

Summary Points: GDF-5 treated MDSCs increased the maximum failure strength and stiffness of flexor tendon within a fibrin gel scaffold in our tissue culture model. Fibrin gel was significantly better than collagen gel as a cell carrier. Further in vivo study would be needed to confirm clinical validity in the future.

References: Reference 1: Chirieleison et al. Tissue Eng Part A. 2012;18(3-4):232-41 Reference 2: Hayashi et al. J Hand Surg Eur Vol. 2011;36(4):271-9.

♦ No relevant financial relationships to disclose

E-poster 13: Nonoperative Treatment Of Olecranon Fractures In Patients Between 17 And 85 Years Old: A Retrospective Review

Category: Treatment, Therapy/Rehabilitation, Prognosis/Outcomes Keyword: Elbow and Forearm, Diseases and Disorders Level 3 Evidence

♦ Christy Christophersen, BS ♦ Matthew D. Putnam, MD ● Julie E. Adams, MD

Hypothesis: Commonly nonoperative treatment of olecranon fractures is reserved for elderly low demand patients. Although olecranon fractures are treated often operatively, nonoperative treatment of certain olecranon fractures should be considered. In this study, we document outcomes following nonoperative treatment of Mayo type I & II olecranon fractures. Our hypothesis was that there is a high rate of acceptable outcomes and a low complication in all age groups

Methods: We performed a retrospective review to identify all skeletally mature patients with a nonoperatively olecranon fracture over a 7 year period. Radiographs were reviewed to measure displacement and determine fracture type according to Mayo Classification. Those with Mayo type II fractures were offered operative or nonoperative management; while Mayo type I fractures were treated nonoperatively. Mayo type III fractures were excluded from this treatment option. Patients were treated with a splinting protocol and followed until clinical and radiographic healing. Demographic data and information regarding range of motion, complications, treatment failures and the Mayo elbow performance index (MEPI) were abstracted from the medical record.

Results: We identified 22 isolated olecranon fractures (12 men; 10 women), with mean age of 46.8 years (range: 17 - 85). Patients sustained Mayo type I (n = 5, 24%) or Mayo type II fractures (n = 16, 76%). Most patients’ mechanism of injury was a fall from a standing height (81%; n=17). Two patients were excluded due to insufficient follow up. Of the remaining patients at average follow up (44 days-Mayo I ; 68 days -Mayo type II) , the mean MEPI value was 91 for Mayo type I and 94 for Mayo type II fractures. Average flexion arc at follow up was 1380 and 1390 for Mayo type I and II, respectively. No patients underwent surgery for a symptomatic nonunion. However, 1 patient sustained another fall from standing height and an olecranon fracture through the bony callus most likely due to an incomplete union or persistent weak spot in the bone 3 months after his initial injury. He underwent ORIF uneventfully.

Summary Points: This study demonstrates that nonoperative treatment of Type I and II fractures has a high rate of good to excellent outcomes (86%, n=19) across age groups and a low complication rate; no patient had a poor outcome. In our series, 73% of patients were under the age of 60 years. Thus, consideration should be given to treating displaced olecranon fractures nonoperatively even in young patients.

References:

● Royalty: Biomet (Adams) Consulting Fee: Arthrex, Articulinx (Adams) Other (Please describe): Elsevier (honorarium) (Adams)

♦ No relevant financial relationships to disclose

E-poster 14: The Patient Perspective of Recovery Following Complete Avulsion Brachial Plexus Injuries

Category: Treatment, Therapy/Rehabilitation, Prognosis/Outcomes Keyword: Nerve Level 4 Evidence

♦ Kevin C Chung, MD, MS ♦ Lauren Franzblau

Hypothesis: The purpose of this study was to evaluate patient perspectives and self-reported outcomes following traumatic complete avulsion brachial plexus injury (BPI).

Methods: 12 male patients of age 25-66 years (mean, 37 y.) participated in this study, seven of whom had reconstructive surgery 3 or more years ago. Time since injury was 2-24 years (mean, 7.7 y.). We followed a mixed-method approach, using grounded theory qualitative methodology and three questionnaires. Participants were interviewed in-person about their experiences using a semi- structured guide. Interview data were coded and analyzed for themes. Questionnaire scores for subjects who did and did not have reconstructive surgery were compared using Mann Whitney U tests.

Results: Coding revealed four categories of themes: employment, physical effects, reflections and regrets about treatment, and satisfaction. Only two of 11 who were employed prior to BPI returned to the same job. Reduced employability was considered the greatest limitation of BPI by six subjects (Figure 1). Ten experienced chronic pain and all participants were limited functionally. Six reported receiving inadequate information regarding diagnosis and treatment that caused them to miss the opportunity for primary reconstruction. Of the seven subjects who had reconstructive surgery, five were satisfied with the results, and four felt their expectations had been met. The Michigan Hand Outcomes Questionnaire revealed marked dissatisfaction with function and aesthetics, poor work ability, and inability to complete one- or two-handed daily tasks using the affected arm (Table 1). Likewise, the Short Form-36 showed functional impairment and high levels of pain (Table 1). Only one third of participants reported being satisfied with the appearance of their arms, hands, and shoulders on a modified Satisfaction with Appearance Scale. There were no significant differences between the scores of patients who did and did not have reconstructive surgery.

Summary Points: • In the patient’s eyes, reconstructive surgery may not produce meaningful gains in function or aesthetic improvements, even when it is a technical success. Furthermore, it does not facilitate return to work, which is a top concern for patients. • Incorporating the patient perspective into treatment planning and goals is critical to providing patient-centered care and achieving high levels of patient satisfaction. Current treatment modalities for brachial plexus avulsion injuries may not generate results that are desirable to patients. Physicians who care for these patients must carefully discuss the available options with patients to ensure that clinical decisions align with patient

♦ No relevant financial relationships to disclose

E-poster 15: Electrophysiological Assessment of Carpal Tunnel Syndrome in Patients over 70 Years of Age.

Category: Prognosis/Outcomes Keyword: Nerve Level 4 Evidence

♦ Takako Kanatani, MD ♦ Issei Nagura, MD ♦ Takeshi Kokubu, MD ♦ Yutaka Mifune, MD ♦ Atsuyuki Inui, MD ♦ Fumiaki Takase, MD

Hypothesis: We hypothesized that elderly (>70 years of age) carpel tunnel syndrome (CTS) patients present favorable recovery rates after carpal tunnel release (CTR). We proposed to assess this objectively by use of our electrophysiological severity scale.

Methods: The electrophysiological status of preoperative severity and of one-year postoperative recovery after CTR by small skin incision was evaluated. The study investigated 120 hands, all over 70 years of age classified by the use of the following electrophysiological severity scale: Stage 1, Normal DML and normal SCV; Stage 2, DML ?4.5ms and normal SCV; Stage 3, DML ?4.5ms and SCV <40.0 m/s; Stage 4, DML ?4.5ms and non-measurable SCV; Stage 5; non-measurable DML and non-measurable SCV.

Results: The mean age of patients was 77.0 years at the time of the operation (range 70-92 years). Preoperatively, the patients were classified as follows; Stage1: 0, Stage 2: 3, Stage 3: 7, Stage 4: 37 and Stage 5: 73, where the most common severity was Stage 5 (60.8%). Clustering stage 4 and 5 together as “severe” resulted in 110 hands (91.7%). One-year postoperatively, the hands were classified; Stage 1: 15, Stage 2: 32, Stage 3: 31, Stage 4: 32 and Stage 5: 10, where 103 hands (85.8%) demonstrated at least one stage improvement. The numbers of “mild” (stage 1 or 2) were significantly increased from 3 to 47 hands (2.5 to 39.2% ) (p<0.0001).

Summary and Points: Elderly carpel tunnel syndrome (CTS) tend to have clinically advanced stage symptoms and is expected to compromise their recovery after CTR due to the potential detrimental effects of advancing age on nerve degeneration. However, we demonstrated a good postoperative recovery in elderly patients of this age group by using our electrophysiological severity scale in this study. This is comparable to the clinical outcomes reported previously1-4). Additionally, our classification by the electrophysiological severity scale is useful for assessing CTS objectively.

References: Reference 1: Leit, ME, Weiser RW, Tomanio MM. Patient reported outcome after carpal tunnel release for advanced disease: A prospective and longitudinal assessment in patients older than 70. J Hand Surg 2004; 29A: 379-83. Reference 2: Townshend DN, Tayler PK, Gwynne-Jones DP. The outcome of carpal tunnel decompression in elderly patients. J Hand Surg 2005; 30A: 501-5. Reference 3: Tomaino MM and Weiser RW. Carpal tunnel release for advanced disease in patients 70 yeas snd older: does outcome from the patients perspective justify surgery? J Hand Surg 2001; 26B: 481-483. Reference 4: Weber RA, Rude MJ. Clinical outcome of carpal tunnel release in patients 65 and older. J Hand Surg 2005; 30A: 75-80.

♦ No relevant financial relationships to disclose

E-poster 16: Feasibility of the ECRB motor branch nerve transfer to the FPL branch for AIN palsy: A cadaveric study

Category: Surgical Technique, Anatomy Keyword: Elbow and Forearm N/A - Not a clinical study

♦ Yasufumi Ogawa, MD ♦ Kazuki Kuniyoshi, MD,PhD ♦ Takane Suzuki, MD,PhD ♦ Koji Sukegawa, MD ♦ Masataka Shibayama, MD ♦ Seiji Okamoto, MD

Hypothesis: Tendon transfer to the ECRB for AIN palsy sometimes brings about unfavorable results due to tendon adhesion and joint contracture during the immobilization period. Lately, favorable results from ECRB motor branch nerve transfer to the FPL branch have been reported. We examined the feasibility of this nerve transfer.

Methods: This study was conducted on both forearms of five fresh frozen cadavers. The radial and median nerves were dissected at the elbow and traced distally to identify the branches that innervated the ECRB and the FPL. Nerve transfer was performed, and we measured the length and diameter of both nerves, identified the points where the nerves could be transferred, and measured the number of the myelinated fibers in the stump.

Results: The length of the nerves that can be used for transfer was 68.3±12.1mm in ECRB and 28.4±4.6mm in FPL. The average diameter of the ECRB was 1.3±0.3mm, whereas that of the FPL was 1.1±0.2mm. The branch of the ECRB could be directly connected to the terminal branch of the FPL in all studies. The points where the nerves could be transferred was 8.0 ± 2.3mm radial from middle line and 63.1 ± 4.3mm distal from the epicondylar line. The number of myelinated fibers in the distal branch of the ECRB was 468±23, whereas that of the FPL was 406±16. There was no statistical difference in the mean diameter or number of myelinated fibers between the ECRB and the FPL.

Summary Points: The distal branch of the ECRB could reach the FPL nerve directly in all specimens. Moreover, the length of the FPL branch can be extended by separating the branch from the AIN. Both branches are well matched in diameter and the number of myelinated fibers. This method can be a useful surgical option for the reconstruction of thumb function in AIN palsy.

♦ No relevant financial relationships to disclose

E-poster 17: Radiation Exposure to the Surgeon’s Hands: A Practical Comparison of Large and Mini C-arm Fluoroscopy

Category: Treatment, Surgical Technique, Historical Information, Basic Science, Medical/Legal Keyword: Hand and Wrist, Diseases and Disorders, General Principles, Practice Management N/A - Not a clinical study

♦ Michael Vosbikian, MD ♦ Charles F Leinberry, MD ♦ Asif Ilyas, MD

Hypothesis: Controversy persists as to whether mini C-arm fluoroscopy units are safer than standard units. In particular, radiation exposure and risks to the surgeon’s hand, which is often closest to the surgical field, is also not well understood. The goal of this study was to determine and compare the radiation exposure to the hand surgeon’s hands with use of a standard and mini C-arm fluoroscopy units in a practical, clinically-based model.

Methods: Two attending hand surgeons monitored the radiation exposure to their hands with a ring dosimeter over a 14 month period using standard and mini C-arm fluoroscopic units. One surgeon performed all cases with a standard C-arm unit in a hospital setting, while the other performed all cases with mini C-arms in surgical centers. For each case, fluoroscopic time, the final dose displayed on the unit, and radiation per unit time were recorded and analyzed.

Results: A total of 160 consecutive cases were reviewed with 71 cases and 89 cases in the standard and mini C-arm limbs of the study, respectively. The median fluoroscopy time per case was 37.7 seconds with the large C-arm and 88 seconds with the mini C-arm. The median dose reported by the large C-arm was 0.68 mGy/case, while the median dose reported by the mini C-arm was 9.97 mGy/case. With dose as a product of time, the median calculated values were 0.02 mGy/second for the large C-arm group and 0.28 mGy/second for the mini C-arm group. The ring exposures showed an exposure of 380 mrem and 1100 mrem for the large and small C-arm group, respectively.

Summary Points: The mini C-arm resulted in more than a ten time increase in radiation exposure dose and more than 3 time greater dosimeter absorption to the surgeon’s hand, compared to the standard C- arm. While it has been shown that the mini C-arm produces less scatter of ionizing radiation, in a practical model, the mini C-arm may not be a safer alternative to the large C-arm with respect to the surgeon’s hands. Though below the maximum recommended radiation dose per year with either model, based on these findings, we would recommend taking appropriate precautions against radiation exposure by utilizing protective equipment and minimizing fluoroscopic time.

♦ No relevant financial relationships to disclose

E-poster 18: The Effects Of Selective Activation Of First Dorsal Interosseous And Opponens Pollicis Muscles On Trapeziometacarpal Joint Kinematics: A Cadaver Study

Category: Therapy/Rehabilitation, Basic Science Keyword: Hand and Wrist, Diseases and Disorders N/A - Not a clinical study

♦ Erik A. Magnusson, BS ♦ VIrginia O'Brien, OTR, CHT ♦ Benjamin E. Rosenstein, MS ● David J. Nuckley, PhD ● Julie E. Adams, MD

Hypothesis: Activation of the first dorsal interosseous (DI) & opponens pollicis (OP) stabilize the thumb carpometacarpal joint (CMCj) (1- 4). We performed a cadaver study describing kinematics of the CMCj during simulated pinch with activation of the DI & OP.

Methods: 10 cadaver arms were dissected & the abductor pollicis longus (APL) & brevis (APB), extensor pollicis longus (EPL) & brevis (EPB), flexor pollicis longus (FPL) & brevis (FPB), index flexor digitorum profundus (FDP-I), adductor pollicis (AdP), DI, & OP muscles were tagged for pinch load application. Fixed weights were attached to each muscle according to a previously described method(5); uniquely, the DI & OP had progressively increasing forces applied. Position and rotation of the CMCj were recorded using 3 sensors: 1-trapezium (T), 2-1st metacarpal (MC), 3-a calibration sensor. The coordinate system (proximal (x+)/distal(x-); ulnar(y+)/radial(y-) and z-dorsal(z+), volar(z-)) was established. Data were collected in 4 states: 1- loaded state without DI or OP activation (baseline), 2-baseline + activation of OP from 0-40N, 3- baseline + activation of DI from 0-30N & 4-baseline + OP (0-40N) & DI (0-30 N). Position & rotation of the 1st metacarpal across the CMCj were recorded and normalized by MC length.

Results: Are detailed in Figures 1 and 2. Fig 1: Average change in MC position (mm) across the CMCj. Loaded state represents change from unloaded to pinched state. Upon loading, greatest CMCj positional changes are in the X & Z planes (Fig2). Loading OP simultaneously translates the MC proximally, palmward and lessens the upward pull of the pinched state. The DI has its greatest effects in the Z plane as it draws the CMCj upward. The DI also attenuates the proximal translation of the MC. As a pair, OP & DI act on the T to halt the proximal translation which may be caused by the loaded MC pushing across CMCj & reduce subluxation by centering the MC on the trapezium. Summary Points: - OP and FDI act synergistically to center the MC on the trapezium and reduce subluxation during simulated pinch. - The OP is the predominant corrective force but has a tendency to overcorrect if unopposed. - The DI tempers action of the OP and contributes to improved CMCj congruency.

References: Reference 1: 1. Adams JE, O’Brien V, Van Nortwick S et al. Activation of the First Dorsal Interosseous muscle results in radiographic reduction of the thumb CMC joint: Implications for basilar joint arthritis intervention. International Thumb Investigator’s Workshop. Newport, Rhode Island. First Annual meeting 10/25/13. Reference 2: 2. O’Brien V, Giveans M. Effects of dynamic stability approach in conservative intervention of the carpometacarpal joint of the thumb: a retrospective study. J Hand Ther. 2013; 1:44-51 Reference 3: 3. Albrecht JA,. Caring for the Painful Thumb: More than a Splint. North Mankato: Corporate Graphics; 2008. Reference 4: 4. Boutan, M. (2000). Role du couple opposant-1er interosseux dorsal dans la stabilité de l'articulation trapezo-metacarpienne. Annals de Kinesiotherapie, (27),316-324. Reference 5: 5. Cooney WP, 3rd, Chao EY. Biomechanical analysis of static forces in the thumb during hand function. J Bone Joint Surg Am. 1977;59:27-36

● Salary: Employed by Zimmer Spine in Research and Development (Nuckley) ● Consulting Fee: Zyga Consulting (Nuckley) Arthrex, Articulinx (Adams) ● Fees for Non-CME Services Received Directly from a Commerci (Nuckley) ● Royalties: Biomet (Adams)

♦ No relevant financial relationships to disclose

E-poster 19: Neurological deficit before and after surgical resection of schwannoma in upper extremity

Category: Prognosis/Outcomes Keyword: Nerve Level 4 Evidence

♦ Hideyuki Mizushima, MD ♦ Hitoshi Hirata, MD ♦ Michiro Yamamoto, MD, Ph.D ♦ Katsuyuki Iwatsuki, MD ♦ Shigeru Kurimoto, MD,PhD

Objective: To estimate surgical results of schwannoma in upper extremity.

Methods: We performed a retrospective review of 43 patients with schwannoma of upper extremity operated between 2000 and 2013. 24 patients were male, and 19 were female. The mean age was 49 years olds (range, 15-79). The mean follow up period was 16.6 months (range, 1-66). Seven schwannomas were located in upper arm, 4 in elbow, 9 in forearm, 6 in wrist, 9 in hand, and 8 in finger. The mean size of schwannoma is 23mm. The size of 18 schwannomas were smaller than 2cm, and that of the other 25 were larger than 2cm. We enucleated or resected tumors under loupe magnification or microscope so as not to damage fascicles. We estimated whether there is neurological deficit or not before and after surgery.

Results: All tumors are diagnosed as schwannoma histopathologically. In 34 patients of all 43, there are some neurological deficits, such as pain, numbness, sensory loss, and motor paralysis, before operation. In 31 patients of these 34, neurological deficit reduced or disappeared after surgery. In 20 patients of all 43, new neurological deficits, which hadn’t been observed before surgery, occurred after surgery. In 5 patients of these 20, new neurological deficit was disappeared in the course of time, and finally in 15 patients some symptom remained. In 15 patients of all 43, one or more fascicles couldn’t be preserved during resection of schwannoma. In 7 patients of these 15, new neurological deficits remained. Otherwise in 8 patients of the other 28, new neurological deficits remained (N.S.). In 11 patients tumor were located in proximal of elbow, and in 7 patients of these 11, new neurological deficit remained. Otherwise in 32 patients tumor were located in distal of forearm, and in 8 of these 32 new neurological deficit remained. More new neurological deficits remained in the tumor located in proximal of elbow than in distal of forearm (p<0.03). One or more fascicles couldn’t be preserved during resection of tumor in12 of 25 tumors which is larger than 2cm, and in 3 of 18 tumors which is smaller than 2cm (P<0.04).

Summary Points: In this study, new neurological deficit occurred in 20cases of all 43cases. This occurrence ratio is higher than we think. We should be more and more careful during operation especially in schwannomas located in proximal of elbow.

References: Reference 1: Sawada T, et al. The relationship between pre-operation symptoms, operative findings and postoperative complication in schwannomas. Jounal of Hand Sugery, 31B : 629-634, 2006 Reference 2: Kang HJ, et al. Schwannomas of the upper extremity. The Journal of Hand Surgery, 25B : 604-607,2000 Reference 3: Rockwell GM, et al. Schwannoma of Hand and Wrist. Plastic and Reconstructive Surgery, March 2003 111 (3); 1227-1232 Schwannoma of Hand and Wrist. Plastic and Reconstructive Surgery, March 2003 111 (3); 1227-1232 Reference 4: Takase K, et al. A Clinical pathology and therapeutic results of neurilemmoma in the upper extremity. Journal of Orthopaedic Surgery 2004 ; 12 (2) :222-225 A Clinical pathology and therapeutic results of neurilemmoma in the upper extremity. Journal of Orthopaedic Surgery 2004 ; 12 (2) :222-225 Reference 5: Adani R, et al. Schwannomas of upper extremity: diagnosis and treatment. Chir Organi Mov (2008) 92: 85-88 Reference 6: Ozdemir O,et al. Schwannomas of the hand and wrist: long-term results and review of the literature. Journal of Orthopaedic Surgery 2005:13(3): 267-272 Reference 7: Knight DMA,, et al.Benign solitary schwannomas. Journal of Bone and Joint Surgery (Br) 2007; 89-B: 382-387 Reference 8: J W Strickland, et al. Nerve tumors of the hand and forearm. Journal of hand surgery 1977; 2, 4, 285-291 Reference 9: J Oberle, et al. Peripheral nerve schwannomas – an analysis of 16 patients. Acta Neurochir (Wien) (1997) 139; 949-953 Reference 10: M J Park, et al. Neurological deficit after surgical enucleation of schwannomas of the upper limb. Journal of Bone and Joint Surgery (Br.) 2009; 91-B: 1482-6

♦ No relevant financial relationships to disclose

E-poster 20: Transverse Compression across the Carpus Decreases Median Nerve Flattening within the Carpal Tunnel

Category: Evaluation/Diagnosis, Treatment, Basic Science Keyword: Hand and Wrist, Nerve Level 4 Evidence

♦ Zong-Ming Li, PhD ♦ Joseph N. Gabra, BS ♦ Peter J. Evans, MD, PhD, F ♦ Tamara L. Marquardt, BS ♦ William H. Seitz, Jr., MD

Hypothesis: Transverse compression across the carpus has been shown to narrow the carpal arch width, thereby increasing the cross-sectional area of the carpal arch (Li et al., 2013). Therefore, it was hypothesized that the median nerve within the carpal tunnel would become less flattened during transverse, compressive force application across the carpus.

Methods: Six, healthy subjects participated in this study (n=6, male, 27.7 ± 6.7 years old). A custom apparatus was used to apply a radial-ulnar, compressive force of 20 N across the right carpus of each subject at the distal level of the carpal tunnel. Axial ultrasound images of the median nerve within the carpal tunnel were captured at the level of the hook of hamate immediately prior to force application (no compression) and at 2-minutes of force application (compression). Three trials were collected with five minutes of rest between consecutive trials. For each ultrasound image, the median nerve was identified and traced within the hyperechoic border of the epineurium using ImageJ software (NIH, Bethesda, MD). The perimeter, area, circularity, and flattening ratio (i.e. aspect ratio, major axis/minor axis) of the median nerve were calculated for the no compression and compression conditions. Paired t-tests were used to investigate the effect of compression on the nerve shape descriptors.

Results: Shape differences were found for the median nerve during the compression condition compared to the no compression condition (Figure 1). The nerve perimeter decreased by 1.10 ± 0.74 mm (p < 0.05) during compression, but its cross-sectional area was preserved (p=0.29) at 8.68 ± 1.81 mm2 and 8.99 ± 1.43 mm2 for the no compression and compression conditions, respectively. The circularity of the median nerve increased from 0.55 ± 0.09 at no compression to 0.67 ± 0.07 during compression (p < 0.01). Additionally, the flattening ratio decreased while compression was applied, from 3.81 ± 0.73 with no compression to 2.83 ± 0.43 with compression (p < 0.01). Summary Points: • The increased circularity and decreased flattening ratio of the median nerve indicates that that the nerve becomes more rounded as a result of external, transverse compression across the carpus. • These median nerve shape changes may be attributable to an increase in the cross-sectional area of the carpal arch associated with carpal arch width narrowing1. • Biomechanical manipulation of the carpal tunnel may decompress the median nerve and relieve symptoms associated with carpal tunnel syndrome.

References: Reference 1: Li ZM, Gabra JN, Marquardt TL, Kim DH. Narrowing carpal arch width to increase cross-sectional area of carpal tunnel-a cadaveric study. Clin Biomech 28(4):402-407, 2013.

♦ No relevant financial relationships to disclose

E-poster 21: Triceps motor branch transfer for Isolated Traumatic Pediatric Axillary Nerve Injuries

Category: Evaluation/Diagnosis, Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Congenital and Pediatric Problems, Nerve Level 4 Evidence

♦ Harvey Chim, MD

Hypothesis: Transfer of the triceps motor branch has been used for treatment of isolated axillary nerve palsy in the adult population. However there is no published data of the effectiveness of this procedure in the traumatic pediatric population. We reviewed demographics and outcomes in our series of pediatric patients.

Methods: Six patients with ages ranging from 10 to 17 years underwent triceps motor branch transfer for the treatment of isolated axillary nerve injuries between 4 to 8 months after the inciting injury. Deltoid muscle strength was evaluated using the modified British Medical Research Council (MRC) grading system. Shoulder abduction at last follow-up was measured.

Results: Mean duration of follow-up was 38 months. Average postoperative MRC grading of deltoid muscle strength was 3.6 + 1.3. One patient who did not achieve M3 grading had multiple injuries from high velocity trauma. Unlike in the adult population, age, BMI of the patient and delay from injury to surgery were not significant factors affecting the outcome of the procedure.

Summary Points: - Pediatric patients with traumatic isolated axillary nerve injury treated with triceps motor branch transfer can have good outcomes but are not without failures

♦ No relevant financial relationships to disclose

E-poster 22: Impact of Joint Position and Joint Morphology on Assessment of Thumb Metacarpophalangeal Joint Radial Collateral Ligament Integrity

Category: Evaluation/Diagnosis, Anatomy Keyword: Hand and Wrist N/A - Not a clinical study

♦ Noah Shaftel, MD ♦ Omri Ayalon, MD ♦ Steven M. Green, MD ♦ Anthony Sapienza, MD ♦ Shian Liu, MSIV

Hypothesis: We hypothesized that RCL strain of the thumb MP joint increases as flexion of the joint increases. We also hypothesized that MP joints with increasing radii of curvature in the coronal plane (flatter head) would have less radial laxity with both intact and sectioned RCL.

Methods: 14 fresh frozen cadaveric thumbs were disarticulated at the thumb carpometacarpal joint. Radii of curvature of the metacarpal heads were measured using fluoroscopic images by 4 independent observers. The specimens were then mounted in a custom jig. Metal markers were placed in the origin and insertion of the RCL. A digital micrometer was used to measure the RCL length as the thumb was placed through a flexion/extension arc with a 200g ulnar deviation stress load. Strain was then calculated at maximum hyperextension, 0, 15, 30, 45 degrees, and maximal flexion. Radial instability was measured with a goniometer while a 45N stress force was applied to the MP joint to simulate clinical stress testing. This was measured at 0, 15, 30, 45 degrees, and maximum flexion. The RCL was then sectioned and the measurements were repeated. Student's t-test were used to assess differences in strain at varying positions. ANOVA and Pearson correlation tests were used to assess for correlation between metacarpal head radius of curvature and radial instability at varying degrees of MP flexion.

Results: The mean RCL strain was statistically greatest 45 degrees of flexion. There was a statistically significant decrease in strain from 45 degrees to maximal flexion. The mean radius of curvature of the metacarpal head was 19+/-4mm. The degree of radial instability was found to have a statistically significant inverse correlation to the radius of curvature (larger the radius of curvature, less radial instability). This correlation was present only when the RCL was sectioned and the joint was stressed at 0 and 15 degrees of flexion. Summary Points: -RCL strain of the thumb MP joint is greatest at 45 degrees of MP flexion and decreases past this point. -Metacarpal head morphology affects measurement of radial laxity when the RCL is sectioned, but only at 0 and 15 degrees of extension. -RCL integrity should be examined with the MP joint flexed to 45 degrees and should not be examined in 0 or 15 degrees extension . -If joints with flatter heads are examined at full or near full extension, the surgeon may underestimate the amount of laxity present, and may incorrectly assess RCL integrity.

References: Reference 1: Edelstein DM, Kardashian G, Lee SK. Radial collateral ligament injuries of the thumb. J Hand Surg. 2008;33(5):760–770 Reference 2: Loebig, TG, Anderson DD, Baratz ME, Imbriglia JE. Radial instability of the metacarpophalangeal joint of the thumb. J Hand Surg. 1995;20(1):102–104 Reference 3: Camp RA, Weatherwax RJ, Miller EB. Chronic posttraumatic radial instability of the thumb metacarpophalangeal joint. J Hand Surg. 1980;5(3):221–225. Reference 4: Yoshida R, House HO, Patterson RM, Shah MA, Viegas SF. Motion and morphology of the thumb metacarpophalangeal joint. J Hand Surg. 2003;28(5):753–757 Reference 5: Adams BD, Muller DL. Assessment of thumb positioning in the treatment of ulnar collateral ligament injuries. A laboratory study. Am J Sports Med. 1996;25(5):672–675. Reference 6: Melone CP, Beldner S, Basuk RS. Thumb collateral ligament injuries. An anatomic basis for treatment. Hand Clin. 2000;16(3):345–357. Reference 7: Stener B. Displacement of the ruptured ulnar collateral ligament of the metacarpo- phalangeal joint of the thumb. J Bone Jt Surg. 1962;44(4):869–879. Reference 8: Smith R. Post-traumatic instability of the metacarpophalangeal joint of the thumb. J Bone Jt Surg. 1977;59(1):14–21.

♦ No relevant financial relationships to disclose

E-poster 23: Acquired Upper Extremity Growth Arrest

Category: Evaluation/Diagnosis, Treatment Keyword: Hand and Wrist, Elbow and Forearm, Congenital and Pediatric Problems Level 4 Evidence

♦ Erich Gauger, MD ♦ Lauren Smith, BS ♦ Deb Bohn, MD ♦ Ann E. Van Heest, MD

Hypothesis: The goal of this study is to evaluate the clinical history and management of acquired upper extremity growth arrest of pediatric patients.

Methods: A retrospective review of all patients presenting to a single institution from 1996 to 2014 with radiographically proven acquired growth arrest was completed. Records were reviewed to determine the cause and site of growth arrest as well as management and complications. Patients with tumors or hereditary etiology were excluded.

Result: Forty-three patients (21 boys, 22 girls) with a total of 59 physeal growth arrests presented at a mean age of 10 years old (0.8-17.3) with an estimated mean age at the time of physeal insult of 6.5 years old (0-15.8). The distal radius was the most common site of arrest (n=19) followed by metacarpal (n=17), distal humerus (n=8), distal ulna (n=5), proximal humerus (n=4), radial head (n=3), phalanx (n=2), and olecranon (n=1). Physician referral was the reason for presentation in 20 cases followed by parent/patient recognition of limb length discrepancy or functional limitation (n=12), pain (n=9) and routine surveillance for growth arrest after fracture (n=2). Growth arrest was secondary to trauma (n=17), infection (n=11), idiopathic (n=10), inflammatory (n=2) compartment syndrome (n=2) and avascular necrosis (n=1). Twenty-two patients (51%) had surgery to address the limb deformity with 5 patients having multiple surgeries. Thirteen out of 19 patients (68%) with distal radius growth arrest underwent a surgical procedure to correct for abnormal ulnar variance. Additionally, 3 patients with physeal arrest of the distal ulna, 3 distal humerus, 2 metacarpal, 1 proximal humerus and 1 radial head were treated operatively. Operative intervention included epiphysiodesis (n=27), lengthening osteotomy (n=8), shortening osteotomy (n=4), other osteotomy (n=2), excision physeal bar/bone fragment (n=2), and creation of single bone forearm (n=1). There were three complications, one deep infection requiring multiple irrigation and debridements, removal of implants and placement of external fixator, one loss of ulnar staple fixation requiring revision and one failure of distal ulna physeal arrest after epiphysiodesis. Summary Points: -Acquired upper extremity growth arrest was most commonly caused by trauma or infection. -The most frequent site of growth arrest in the upper extremity is the distal radius followed by the metacarpal, distal humerus, distal ulna, proximal humerus, radial head, phalanx and olecranon. -Growth disturbances due to premature arrest can effectively be treated by epiphysiodesis or osteotomy. -Periodic monitoring after injury or infection is recommended to evaluate for growth arrest.

References: Reference 1: Gkiokas A, Brilakis E. Spontaneous correction of partial physeal arrest: Report of a case and review of the literature. J Pediatr Orthop B. 2012;21(4):369-372. Reference 2: Hove LM, Engesaeter LB. Corrective osteotomies after injuries of the distal radial physis in children. J Hand Surg Br. 1997;22(6):699-704. Reference 3: Katz K, Goldberg I, Bahar A, Yosipovitch Z. Humeral lengthening for septic neonatal growth arrest. J Hand Surg Am. 1989;14(5):903-907. Reference 4: Macnicol MF, Anagnostopoulos J. Arrest of the growth plate after arterial cannulation in infancy. J Bone Joint Surg Br. 2000;82(2):172-175. Reference 5: Peters W, Irving J, Letts M. Long-term effects of neonatal bone and joint infection on adjacent growth plates. J Pediatr Orthop. 1992;12(6):806-810. Reference 6: Waters PM, Bae DS, Montgomery KD. Surgical management of posttraumatic distal radial growth arrest in adolescents. J Pediatr Orthop. 2002;22(6):717-724.

♦ No relevant financial relationships to disclose

E-poster 24: A comparative study of fluoroscopic versus arthroscopic reduction of intra-articular unstable distal radial fractures

Category: Surgical Technique Keyword: Hand and Wrist Level 2 Evidence

♦ Hiroshi Yamazaki, MD ♦ Hiroyuki KATO, MD ♦ Toshiro Itsubo, MD ♦ Shigeharu UCHIYAMA, MD

Hypothesis: This study compares radiographic and clinical outcomes of arthroscopically and fluoroscopically assisted reduction techniques for treatment of intra-articular distal radius fractures.

Methods: Sixty-eight patients with unstable intra-articular distal radius fractures were treated with either fluoroscopic or arthroscopic reduction. We evaluated and compared radiographic outcomes including ulnar inclination, volar angulation, ulnar variance, gap, and step, functional outcomes that included active range of motion of the wrist and grip strength, and patient-rated outcomes via Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaires at 3, 6, and 12 months postoperatively.

Results: Gap and step in the fluoroscopic and arthroscopic groups were comparable at 1.6±1.6 mm and 1.7±1.5 mm and 0.9±1.0 mm and 0.7±0.7 mm, respectively (P=.55 and P=.24). No significant differences between the techniques were found with regard to radiographic parameters, functional outcomes, or patient-rated outcomes. Summary Points Arthroscopic reduction may not be necessary for the sole purpose of confirming anatomic reduction of intra-articular distal radius fractures.

♦ No relevant financial relationships to disclose

E-poster 25: Annular Ligament Reconstruction for Chronic Radial Head Instability: A Modified Anatomic Technique

Category: Surgical Technique, Anatomy Keyword: Elbow and Forearm, Congenital and Pediatric Problems Level 4 Evidence

♦ Michael D Smith, M.D. ♦ S. Houston Payne, Jr., MD ♦ Scott H. Kozin, MD ♦ John G. Seiler, III, MD

Hypothesis: Chronic radiocapitellar instability following trauma is a difficult problem. Traditionally, persistent radiocapitellar instability after restoration of radial and ulnar alignment has been managed with annular ligament reconstruction. Most notable amongst the described reconstruction techniques is the Bell Tawse triceps reconstruction. This technique, however, has been associated with significant complications, including loss of radiocapitellar reduction, elbow stiffness, premature closure of the proximal radial physis and radial neck notching. Our hypothesis is that utilization of a modified anatomic technique for reconstruction of the annular ligament will confer increased stability to the radiocapitellar joint while improving pain-free range of motion.

Methods: Six patients, ages 5 to 14, were evaluated for chronic radiocapitellar instability after either a Monteggia fracture or elbow dislocation. The radiocapitellar joint was found to be subluxed or dislocated on pre-operative radiographs (Image 1) and radiocapitellar joint congruity was confirmed. The patients underwent anatomic reconstruction of the annular ligament using palmaris longus or flexor carpi radialis autograft in five patients and allograft in one patient. The technique utilized a Thompson approach to the elbow and anatomic drill holes in the ulna (Image 2). Three patients required ulnar osteotomy to restore ulnar length. The patients were then splinted in 45 degrees of flexion and forearm supination for 6 weeks. Passive physiotherapy was initiated at the time of splint removal and activity was advanced to no limitations by 12 weeks. Post-operative radiographs were obtained at 6 weeks to confirm reduction of the radiocapitellar joint.

Results: Post-operative follow-up ranged from 11 months to five years. Post-operative elbow extension and flexion averaged 5° and 138.3° respectively. Post-operative pronation-supination averaged 63.3° of supination to 62.5° of pronation. After excellent early recovery, the patient with an allograft reconstruction failed at 13 months post-operatively with residual lateral pain and radiocapitellar instability. The remaining five patients report no residual pain or instability; however one patient developed radioulnar synostosis with significant limitation of pronation and supination. There were no other complications.

Summary Points: Chronic radial head instability can occur from a wide variety of mechanisms. Our modified technique of annular ligament reconstruction confers better stability at the radiocapitellar joint with good restoration of joint line mechanics. The anatomic reconstruction utilizes separate drill holes in the ulna and confers a more concentric reduction force to the radial head within the sigmoid notch. This helps improve forearm rotation and lessens the possibility of recurrent radiocapitellar subluxation. Autograft is preferred to allograft for the reconstruction

References: Reference 1: Bell Tawse, A.J., The treatment of malunited anterior Monteggia fractures in children. J Bone Joint Surg Br, 1965. 47(4): p. 718-23 Reference 2: Cappellino, A., S.W. Wolfe, and J.S. Marsh, Use of a modified Bell Tawse procedure for chronic acquired dislocation of the radial head. J Pediatr Orthop, 1998. 18(3): p. 410-4. Reference 3: Oner, F.C. and A.F. Diepstraten, Treatment of chronic post-traumatic dislocation of the radial head in children. J Bone Joint Surg Br, 1993. 75(4): p. 577-81. Reference 4: Seel, M.J. and H.A. Peterson, Management of chronic posttraumatic radial head dislocation in children. J Pediatr Orthop, 1999. 19(3): p. 306-12. Reference 5: Holst-Nielsen, F. and V. Jensen, Tardy posterior interosseous nerve palsy as a result of an unreduced radial head dislocation in Monteggia fractures: a report of two cases. J Hand Surg Am, 1984. 9(4): p. 572-5. Reference 6: Lattanza, L.L. and G. Keese, Elbow instability in children. Hand Clin, 2008. 24(1): p. 139-52. Reference 7: Best, T.N., Management of old unreduced Monteggia fracture dislocations of the elbow in children. J Pediatr Orthop, 1994. 14(2): p. 193-9. Reference 8: Ring, D. and P.M. Waters, Operative fixation of Monteggia fractures in children. J Bone Joint Surg Br, 1996. 78(5): p. 734-9. Reference 9: Thompson, J.D. and A.B. Lipscomb, Recurrent radial head subluxation treated with annular ligament reconstruction. A case report and follow-up study. Clin Orthop Relat Res, 1989(246): p. 131-5. Reference 10: Gyr, B.M., P.M. Stevens, and J.T. Smith, Chronic Monteggia fractures in children: outcome after treatment with the Bell-Tawse procedure. J Pediatr Orthop B, 2004. 13(6): p. 402- 6.

Figure 1

Figure 2

♦ No relevant financial relationships to disclose E-poster 26: Corticosteroid Suppression of Dupuytren's Disease-Derived Stem Cells through Inhibition of Transforming growth factor-ß1 Expression

Category: Basic Science Keyword: Diseases and Disorders N/A - Not a clinical study

♦ Jung-Pan Wang, MD ♦ Shih-Chieh Hung, MD, PhD

Hypothesis: Treatment with corticosteroids was known to diminish the fibrosis and fibrogenic activity (1). TGF-ß1 was reported to increase a-SMA and fibrogenic genes expression (2). TGF-ß1 plays an important role of myofibroblastic differentiation of DDSCs (3). Corticosteroids may inhibit myofibroblastic differentiation of Dupuytren’s disease-derived stem cells (DDSCs) through inhibition of the expression of TGF-ß1 or its signaling pathway.

Methods: The DDSCs were isolated as previously described (4). To determine the effect of dexamethasone on DDSCs, DDSCs was treated with dexamethasone and analyzed by quantitative RT-PCR. To examine whether dexamethasone suppresses TGF-ß1 signaling, we measured the expression of Smad family by western blot analysis. In addition, to examine whether TGF-ß1 was involved in myofibroblastic differentiation of DDSCs, we infected DDSCs with vesicular stomatitis virus protein G (VSV-G) pseudotyped lentivirus carrying RNA interference (RNAi) specific for TGF-ß1 targeting.

Results: Treatment with dexamethasone inhibited the expression of a-SMA, Col3A1 and Col1A3 mRNAs in a dose dependant manner as revealed by quantitative RT-PCR. Immunofluorescence also demonstrated that dexamethasone inhibited the expression of a-SMA and type III collagen. All of these data suggested that dexamethasone suppressed the myofibroblastic differentiation of DDSCs. The western blot analysis demonstrated that pSmad 2/3 was suppressed by dexamethasone in a dose-dependent manner, while there was no obvious suppression or enhancement of Smad 7 and Sp1. The enzyme-linked immunosorbent assay showed that TGF-ß1 protein levels were decreased by dexamethasone. Silencing of TGF-ß1 expression decreased in the immunofluorescence for a-SMA, type III collagen compared to the control.

Summary Points: We demonstrated that dexamethasone suppresses the myofibroblastic differentiation potential of DDSCs. We also demonstrated that that silencing of TGF-ß1 expression inhibits the myofibroblastic differentiation potential of DDSCs. TGF-ß1 could be a useful tool in future researches looking into biological mechanisms of Dupuytren’s disease and therapies targeting the TGF-ß1 signaling pathway may be more effective.

References: Reference 1: Chen F, Gong L, Zhang L, Wang H, Qi X, Wu X, Xiao Y, Cai Y, Liu L, Li X, and Ren J: Short courses of low dose dexamethasone delay bleomycin-induced lung fibrosis in rats. European Journal of Pharmacology 2006, 536:287-295 Reference 2: Mauviel A (2005) Transforming growth factor-beta: a key mediator of fibrosis. Methods in Molecular Medicine 117:69-80 Reference 3: Wang JP, Hui YJ, Wang ST, Huang YC, Chiang ER, Liu CL, Chen TH, Hung SC (2011) Fibromatosis stem cells rather than bone-marrow mesenchymal stem cells recapitulate a murine model of fibromatosis. Biochem Biophys Res Commun 408(2): 269-275 Reference 4: Wang JP, Hui YJ, Wang ST, Yu HH, Huang YC, Chiang ER, Liu CL, Chen TH, Hung SC (2011) Recapitulation of fibromatosis nodule by multipotential stem cells in immunodeficient mice. PLoS One 6(8): e24050

♦ No relevant financial relationships to disclose

E-poster 27: Short-Term Radiographic and Clinical Outcomes of the RASL Procedure

Category: Treatment Keyword: Hand and Wrist Level 4 Evidence

♦ Timothy Larson, MD

Hypothesis: Despite promising results, the reproducibility of the Reduction and Association of the Scaphoid and Lunate (RASL) procedure has been poorly documented in the literature. This study evaluates the success of the RASL procedure in an effort to evaluate its validity and reproducibility.

Methods: A retrospective case series of 7 patients (8 wrists total) was evaluated, with an average follow-up of 38 months. Static and grip radiographs were examined in the preoperative, immediate postoperative, and final follow-up setting, and clinical measurements of grip strength, wrist range of motion Disability of the Arm, Shoulder, and Hand (DASH) and the Patient-Rated Wrist Evaluation (PRWE) outcome questionnaires were recorded.

Results: Radiographic success, defined by maintenance of corrected scapholunate diastasis, absence of DISI deformity and no progression of SLAC degeneration was achieved in only 3 of the 8 wrists. No patients required a salvage procedure. Despite the loss of reduction in all patients, the patients’ disability remains minimal as detected by the DASH (ave. 15) and PRWE (ave. score 26).

Summary Points: • The RASL procedure does not provide stability about the scapholunate interval, the majority of patients experience failure of the procedure. • Despite a high radiographic failure rate, clinical measurements indicate less disability than expected, although this may be attributed to the limited length of follow up. • Because of the high early radiographic failure rate, the RASL procedure is no longer performed by the senior author.

Figure Legend

1. Table 2: Summary of radiographic analysis of all subjects as well as final range of motion

and grip strength measurements. * Denotes wrists deemed to have successful outcome.

†Denotes results for patient with bilateral RASL procedure.

♦ No relevant financial relationships to disclose E-poster 28: Factors Affecting Dealyed Recovery After Surgical Treatment Of Distal Radius Fractures

Category: Evaluation/Diagnosis, Treatment, Therapy/Rehabilitation, Prognosis/Outcomes Keyword: Hand and Wrist, Practice Management Level 2 Evidence

♦ Young Hak Roh, MD ♦ Jong Ryoon Baek, MD ♦ Beom Koo Lee, MD ♦ Hyun Sik Gong, MD ♦ Goo Hyun Baek, MD

Hypothesis: The course of functional recovery after distal radius surgery is different across patients and is important to consider in the process of managing patients with distal radius fracture. This study was performed to evaluate the factors associated with delayed functional recovery in patient after distal radius surgery.

Methods: A total of 176 patients with a distal radius fracture treated surgically were enrolled. The wrist range of motion, grip strength, and functional outcome by the Michigan hand score were assessed 3, 6, and 12 months after surgery. The factors assessed for their influence on delayed functional recovery include age, gender, the body mass index, bone mineral density, the type of fracture, combined soft-tissue injury and the type of surgery. A multivariate regression analysis was conducted to identify independent predictors of delayed functional recovery in terms of the Michigan hand score.

Results: There was a significant decrease in the wrist range of motion in patients with a severe fracture type or open wound and in those treated with external fixation at month 3, whereas only a severe fracture type was associated with a decreased range of motion at months 6 and 12. An increase in age, a decrease in BMD, open wounds, and external fixation reduced grip strength at months 3 and 6, whereas only an increase in age and a decrease in BMD reduced it at month 12. According to the multivariate regression analysis, the external fixation reduced functional outcome at month 3, and the type of fracture and open wounds reduced functional outcomes at months 3 and 6. On the other hand, at month 12, an increase in age and a decrease in BMD reduced functional outcome.

Summary Points: An increase in age and a decrease in BMD were important risk factors influencing delayed functional recovery up to 12 months after distal radius surgery, whereas fracture severity and external fixation were associated with decreased functional outcomes in early postoperative periods up to 6 months after surgery.

References: Reference 1: Chung KC, Shauver MJ, Birkmeyer JD. Trends in the United States in the treatment of distal radial fractures in the elderly. J Bone Joint Surg Am. 2009;91(8):1868-1873. Reference 2: Melton LJ, 3rd, Amadio PC, Crowson CS et al. Long-term trends in the incidence of distal forearm fractures. Osteoporos Int. 1998;8(4):341-348. Reference 3: Egol K, Walsh M, Tejwani N et al. Bridging external fixation and supplementary Kirschner-wire fixation versus volar locked plating for unstable fractures of the distal radius: a randomised, prospective trial. J Bone Joint Surg Br. 2008;90(9):1214-1221. Reference 4: Van Son MA, De Vries J, Roukema JA et al. Health status and (health-related) quality of life during the recovery of distal radius fractures: a systematic review. Qual Life Res. 2013. Reference 5: Bolmers A, Luiten WE, Doornberg JN et al. A comparison of the long-term outcome of partial articular (AO Type B) and complete articular (AO Type C) distal radius fractures. J Hand Surg Am. 2013;38(4):753-759. Reference 6: Souer JS, Ring D, Jupiter JB et al. Comparison of AO Type-B and Type-C volar shearing fractures of the distal part of the radius. J Bone Joint Surg Am. 2009;91(11):2605-2611. Reference 7: Brogren E, Hofer M, Petranek M et al. Fractures of the distal radius in women aged 50 to 75 years: natural course of patient-reported outcome, wrist motion and grip strength between 1 year and 2-4 years after fracture. J Hand Surg Eur Vol. 2011;36(7):568-576. Reference 8: acDermid JC, Roth JH, Richards RS. Pain and disability reported in the year following a distal radius fracture: a cohort study. BMC Musculoskelet Disord. 2003;4(24. Reference 9: Koval KJ, Harrast JJ, Anglen JO et al. Fractures of the distal part of the radius. The evolution of practice over time. Where's the evidence? J Bone Joint Surg Am. 2008;90(9):1855- 1861. Reference 10: Gruber G, Zacherl M, Giessauf C et al. Quality of life after volar plate fixation of articular fractures of the distal part of the radius. J Bone Joint Surg Am. 2010;92(5):1170-1178.

Table 1. Demographics of participants Characteristics Number 176 Mean age 51.2 ± 18.2 Male/Female, n (%) 80 (45%) / 96 (55%) AO fracture type, n (%) Type A 72 (41%) Type B 22 (13%) Type C 82 (47%) Type of surgery, n(%) Volar plating 118 (64%) External fixation 58 (33%) ± intrafocal k-wire fixation

Table 6. Multivariate analysis of predictor of functional recovery at each measurement time

Variables Variables R2 P Functional recovery Open wound, 38 % 0.02 month 3 Fracture type Surgery type Functional recovery BMD 32 % 0.02 month 6 Fracture type Open wound Functional recovery BMD 30 % 0.04 month 12 Older age The value of functional recovery was defined by the ratio of injured/uninjured Michigan hand scores at each measurement time.

♦ No relevant financial relationships to disclose

E-poster 29: To what degree do shoulder outcome instruments reflect patients' psychologic distress?

Category: Evaluation/Diagnosis, Treatment, Therapy/Rehabilitation, Prognosis/Outcomes, Patient Education Keyword: Shoulder and Arm, Diseases and Disorders, Practice Management Level 2 Evidence

♦ Young Hak Roh, MD ♦ Beom Koo Lee, MD ♦ Jong Ryoon Baek, MD ♦ Hyun Sik Gong, MD ♦ Goo Hyun Baek, MD

Hypothesis: Psychologic distress has been demonstrated to contribute to symptom severity in several musculoskeletal disorders. While numerous shoulder outcome instruments are used it is unclear whether and to what degree psychologic distress contributes to the scores. We asked (1) what degree shoulder outcome instruments reflect patients’ psychological distress, and (2) whether patients who are strongly affected by psychological distress can be identified.

Methods: We prospectively evaluated 119 patients with chronic shoulder pain caused by degenerative or inflammatory disorders using the Constant-Murley scale, Simple Shoulder Test (SST), and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. To evaluate psychologic distress, we measured depression using the Center for Epidemiologic Studies-Depression (CES-D) scale and pain anxiety using the Pain Anxiety Symptom Scale (PASS). Demographic and clinical parameters, such as pain scores, ROM, and abduction strength, were also measured. We then assessed the relative contributions made by psychologic distress and other clinical parameters to the quantitative ratings of the three shoulder outcome instruments. Results: Quantitative ratings of shoulder outcome instruments correlated differently with psychologic distress. Constant-Murley scores did not correlate with psychologic measures, whereas SST scores correlated with PASS (r = 0.32, p = 0.025) and DASH scores correlated with PASS and CES-D (r = 0.36, p = 0.011, and r = 0.32, p = 0.022). Psychologic distress contributed to worsening SST and DASH scores but not to Constant-Murley scores. DASH scores were more strongly influenced by pain anxiety and depression than the other two outcome instruments.

Summary Points: Shoulder outcome measures reflected different psychologic aspects of illness behavior, and the contributions made by psychologic distress to different shoulder outcome instruments apparently differed. Physicians should select and interpret the findings of shoulder outcome instruments properly by considering their psychologic implications.

References: Reference 1: Alizadehkhaiyat O, Fisher AC, Kemp GJ, Frostick SP. Pain, functional disability, and psychologic status in tennis elbow. Clin J Pain. 2007;23:482-489. Reference 2: Beaton DE, Richards RR. Measuring function of the shoulder. A cross-sectional comparison of five questionnaires. J Bone Joint Surg Am. 1996;78:882-890. Reference 3: Boyd JH, Weissman MM, Thompson WD, Myers JK. Screening for depression in a community sample. Understanding the discrepancies between depression symptom and diagnostic scales. Arch Gen Psychiatry. 1982;39:1195-1200. Reference 4: Chard MD, Hazleman R, Hazleman BL, King RH, Reiss BB. Shoulder disorders in the elderly: a community survey. Arthritis Rheum. 1991;34:766-769. Reference 5: Constant CR, Murley AH. A clinical method of functional assessment of the shoulder. Clin Orthop Relat Res. 1987;214:160-164. Reference 6: Furner SE, Hootman JM, Helmick CG, Bolen J, Zack MM. Health-related quality of life of US adults with arthritis: analysis of data from the behavioral risk factor surveillance system, 2003, 2005, and 2007. Arthritis Care Res (Hoboken). 2011;63:788-799. Reference 7: Gilbart MK, Gerber C. Comparison of the subjective shoulder value and the Constant score. J Shoulder Elbow Surg. 2007;16:717-721. Reference 8: Goldhahn J, Angst F, Simmen BR. What counts: outcome assessment after distal radius fractures in aged patients. J Orthop Trauma. 2008;22:S126-130. Reference 9: Hudak PL, Amadio PC, Bombardier C. Development of an upper extremity outcome measure: the DASH (disabilities of the arm, shoulder and hand). The Upper Extremity Collaborative Group (UECG). Am J Ind Med. 1996;29:602-608. Reference 10: Kim KW, Han JW, Cho HJ, Chang CB, Park JH, Lee JJ, Lee SB, Seong SC, Kim TK. Association between comorbid depression and osteoarthritis symptom severity in patients with knee osteoarthritis. J Bone Joint Surg Am. 2011;93:556-563.

Table 2. Scores on clinical, shoulder outcome, and psychologic measures

Measure Score

0- to 100-mm VAS for pain (mm) 5.2 ± 2.1 (2–10) ROM total (points*) 19.8 ± 4.9 (8–28) Muscle strength (points*) 23.6 ± 3.4 (5–25) Constant-Murley (points) 65.2 ± 15.4 (21–82) SST (points) 6.8 ± 2.7 (1–10) DASH (points) 22.5 ± 13.3 (5.8–53.0)

CES-D (points) 12.7 ± 7.2 (0–37) Adhesive capsulitis 12.4 ± 6.8 Impingement syndrome 12.1 ± 6.4 Rotator cuff tear 11.5 ± 4.5 Acromiocalvicular arthritis 14.8 ± 10.5 Calcific tendinitss 14.5 ± 12.2

PASS (points) 58.0 ± 39.6 (4–120) Adhesive capsulitis 58.1 ± 38.9 Impingement syndrome 55.3 ± 37.2 Rotator cuff tear 52.1 ± 29.4 Acromiocalvicular arthritis 63.1 ± 38.1 Calcific tendinitss 61.0 ± 41.2 -Cognitive 17.2 ± 16.2 (0–50) -Escape/avoidance 15.4 ± 9.0 (0–34) -Fear 15.1 ± 11.8 (0–30) -Psychological anxiety 10.3 ± 8.1 (0–26)

Values are expressed as mean ± SD, with range in parentheses; * ROM and Muscle strength were converted to Constant subscale scores to facilitate statistical analysis; SST = Simple Shoulder Test; DASH = Disabilities of the Arm, Shoulder, and Hand questionnaire; CES-D = Center for Epidemiologic Studies-Depression; PASS = Pain Anxiety Symptom Scale.

Table 4. Multivariate analysis

Model Constant-Murley score SST DASH Includ β R2 p Includ β R2 p Includ β R2 p ed value ed valu ed valu Variabl Variabl e Variabl e e e e Best-fit Sex 0.1 81. < Sex 0.3 42. 0.00 Sex 0.3 38. 0.02 model 4 2 0.00 2 7 1 1 0 0 1 ROM 0.6 ROM 0.2 ROM 0.2 4 8 1 Pain 0.1 Pain 0.2 Pain 0.1 9 0 6 Streng 0.4 Streng 0.2 CES-D 0.1 th 6 th 0 6 PASS 0.2 PASS 0.1 2 7

Psycholo CES-D 4.4 0.35 CES-D 13. 0.03 CES-D 17. 0.04 gic 0* 2 2 2 8 model PASS PASS PASS

* Psychologic model did not explain the variation in Constant-Murley scores; SST = Simple Shoulder Test; DASH = Disabilities of the Arm, Shoulder, and Hand questionnaire; CES-D = Center for Epidemiologic Studies-Depression; PASS = Pain Anxiety Symptom Scale.

♦ No relevant financial relationships to disclose E-poster 30: Use of sonography-guided arthroscopic excision is more effective for treating volar wrist ganglion than dorsal wrist ganglion

Category: Treatment Keyword: Hand and Wrist Level 3 Evidence

♦ Michiro Yamamoto, MD, Ph.D ♦ Masahiro Tatebe, MD ♦ Takaaki Shinohara, MD ♦ Katsuyuki Iwatsuki, MD, PhD ♦ Hitoshi Hirata, MD

Hypothesis: We previously reported the use of sonography-guided arthroscopy to treat wrist ganglion1). The purpose of this study was to compare the results of sonography-guided arthroscopic excision for volar and dorsal wrist ganglions. We hypothesized that sonography-guided arthroscopic excision is more effective for treating volar wrist ganglion than dorsal wrist ganglion.

Methods: A total of 42 patients (15 men, 27 women; age, 13–73 years) with wrist ganglions who underwent sonography-guided arthroscopic excision between 2008 and 2013 were evaluated. The follow-up period was 16–36 months. The indication for arthroscopic surgery was a persistently symptomatic ganglion after failed nonsurgical treatment. Clinical outcome measures included wrist range of motion, grip strength, our patient-rated Hand 20 questionnaire scores2), and numerical pain rating scale scores. All patients were assessed for recurrence throughout the follow-up period. Clinical outcomes and recurrence rates were compared between patients with volar wrist ganglions and those with dorsal wrist ganglions. Surgical technique A high-frequency linear array transducer at a frequency of 13 MHz was covered with a sterilized drape and was used by an assisting surgeon during the wrist arthroscopy. The arthroscopy and sonography monitors were placed beyond the patient so that the surgeons could view them easily (Figure 1). Arthroscopic debridement continued until the path between the ganglion and joint was completed. Ganglion recurrence was compared using Fisher’s exact probability test. P values < .05 were considered statistically significant.

Results: Ganglions were located at the dorsal wrist in 26 cases and at the volar wrist in 16 cases. The mean range of motion and grip strength did not differ significantly between volar and dorsal wrist ganglia. The mean Hand 20 and pain scores were not significantly different between patients with volar wrist ganglia and those with dorsal wrist ganglia. Ganglion recurrence was seen in six cases of dorsal wrist ganglion but no cases of volar wrist ganglion (P < .05) (Table 1). No intraoperative complications occurred in either group, but in one case in which a ganglion was located volar to the triangular fibrocartilage, we converted the procedure to an open surgery.

Summary Points: Arthroscopic resection of dorsal wrist ganglion is not as easy as once thought. In this study, we found that the recurrence rate of dorsal wrist ganglion was significantly higher than that of volar wrist ganglion. Therefore, the use of sonography-assisted arthroscopic ganglion excision is better for treating volar wrist ganglion than dorsal wrist ganglion.

References: Reference 1: Sonography-guided arthroscopy for wrist ganglion. Yamamoto M, Kurimoto S, Okui N, Tatebe M, Shinohara T, Hirata H. J Hand Surg Am. 2012 Jul;37(7):1411-5. Reference 2: Development and validation of an illustrated questionnaire to evaluate disabilities of the upper limb. Suzuki M, Kurimoto S, Shinohara T, Tatebe M, Imaeda T, Hirata H. J Bone Joint Surg Br. 2010 Jul;92(7):963-9.

TABLE 1. Volar and Dorsal Wrist Ganglion Data

Volar wrist ganglion Dorsal wrist ganglion P Value (n=16) (n=26) Age (year) 42 (+16) 33 (+12) 0.05 Follow up period (month) 19 (+2) 22 (+7) 0.12 Preope wrist flexion 75 (+12) 74 (+18) 0.91 Postope wrist flexion 77 (+12) 76 (+12) 0.89 Preope wrist extension 82 (+10) 75 (+16) 0.28 Postope wrist extension 83 (+10) 82 (+10) 0.66 Preope Hand20 score 17 (+14) 24 (+13) 0.12 Postope Hand20 score 6 (+7) 8 (+12) 0.61 Preope pain score 3.2 (+2) 4.6 (+2) 0.1 Postope pain score 1.0 (+1.5) 1.2 (+1.6) 0.76 Recurrence (number) 0 6 < .05 Data are expressed as mean (+ SD) except for recurrence.

♦ No relevant financial relationships to disclose E-poster 31: Evaluation of Physical Performance Level as a Fall Risk Factor in Women with a Distal Radius Fracture

Category: Evaluation/Diagnosis, Therapy/Rehabilitation, Prognosis/Outcomes Keyword: Hand and Wrist Level 3 Evidence

♦ Hyun Sik Gong, MD ♦ Young Ho LEE, MD ♦ Seung Hwan Rhee, MD ♦ Jihyeung Kim, MD ♦ Goo Hyun Baek, MD

Hypothesis: Decreased physical performance has been associated with an increased risk of fall and fragility hip fractures. However, reports are contradictory regarding the relationship between physical performance and the occurrence of a distal radius fracture. The purpose this study was to compare physical performance measures and fall risk factors in middle-aged and elderly patients with recent distal radius fractures relative to age-matched control patients.

Methods: We prospectively recruited 40 postmenopausal women over 50 years of age who sustained a distal radius fracture due to a fall, and 40 age-matched controls without a recent history of falls. We excluded those with cognitive impairment, neuromuscular diseases, or other chronic conditions affecting muscle function. We compared the two groups for the level of physical performance and other risk factors of a fall. For the level of physical performance, we measured short physical performance battery (walking speed, chair stand, and standing balance), walking distance, and grip strength of unaffected sides. Other known risk factors assessed were; body mass index, history of previous fractures, osteoarthritis, arrhythmia, depression, visual disturbance, hypotension, use of antihypertensive drug, sedatives or hypnotics, antidepressants, and 4 or more medications.

Results: There was no significant difference in the Short Physical Performance Battery summary score between the two groups. Chair stand and grip strengths (adjusted for hand dominance) were significantly lower (p = 0.034, 0.038, respectively) in patients with a distal radius fracture than in controls.

Summary Points: This study suggests that overall physical performance level is not different between women with a distal radius fracture and those without a distal radius fracture. Differences in chair stand test and grip strength may imply an early subtle decrease in physical performance level in patients with distal radius fracture.

References: Reference 1: O'Neill TW, Marsden D, Adams JE, Silman AJ. Risk factors, falls, and fracture of the distal forearm in Manchester, UK. J Epidemiol Community Health. 1996 Jun;50(3):288-92. Reference 2: Rozental TD, Makhni EC, Day CS, Bouxsein ML. Improving evaluation and treatment for osteoporosis following distal radial fractures. A prospective randomized intervention. J Bone Joint Surg Am. 2008 May;90(5):953-61. Reference 3: Nordvall H, Glanberg-Persson G, Lysholm J. Are distal radius fractures due to fragility or to falls? A consecutive case-control study of bone mineral density, tendency to fall, risk factors for osteoporosis, and health-related quality of life. Acta Orthop. 2007 Apr;78(2):271- 7. Reference 4: Mallmin H, Ljunghall S, Persson I, Bergstrom R. Risk factors for fractures of the distal forearm: a population-based case-control study. Osteoporos Int. 1994 Nov;4(6):298-304. Reference 5: Guralnik JM, Simonsick EM, Ferrucci L, Glynn RJ, Berkman LF, Blazer DG, Scherr PA, Wallace RB. A short physical performance battery assessing lower extremity function: association with self-reported disability and prediction of mortality and nursing home admission. J Gerontol. 1994 Mar;49(2):85-94. Reference 6: Kannus P, Sievänen H, Palvanen M, Järvinen T, Parkkari J. Prevention of falls and consequent injuries in elderly people. The Lancet. 2005 Nov;366(9500):1885-93.

♦ No relevant financial relationships to disclose

E-poster 32: Early Results of Anterior Elbow Release with Biceps Lengthening in Patients with Cerebral Palsy: Comparison with Anterior Elbow Release without Biceps Lengthening

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Congenital and Pediatric Problems Level 3 Evidence

♦ Hyun Sik Gong, MD ♦ Young Ho LEE, MD ♦ Seung Hwan Rhee, MD ♦ Min Bom Kim, MD ♦ Jihyeung Kim, MD ♦ Goo Hyun Baek, MD

Hypothesis: Biceps lengthening procedure is often performed as a part of anterior elbow release for flexion deformity in cerebral palsy. However, there has been a concern that this procedure may weaken active elbow flexion and forearm supination. We investigated the effect of partial biceps lengthening on elbow flexion posture and active elbow flexion and extension in patients with cerebral palsy.

Methods: We retrospectively reviewed 29 patients with cerebral palsy that underwent anterior elbow release as part of multi-level upper extremity surgery. The early series of the patients (N = 14, Group 1) had lacertus fibrosus division, brachialis fractional lengthening, and denuding of the pretendinous adventitia off the biceps tendon. The later series of the patients (N = 15, Group 2) had partial biceps tendon lengthening in addition to the aforementioned procedures. We compared the two sets of patients for elbow flexion posture, active elbow flexion and extension, forearm rotation, and House scores with a mean follow up of 72 months for Group 1 and 31 months for Group 2.

Results: The two groups were comparable in terms of the mean age, number of procedures, and preoperative House scores. Group 2 patients had larger improvement in flexion posture (53° vs. 44°) and active extension (23° vs. 15°) than Group 1 postoperatively. However, Group 2 had a mean decrease of 7° in active elbow flexion while Group 1 had no changes. There was no difference in forearm supination or in the improvement of House scores between the groups.

Summary Points: The early results of partial lengthening of the biceps tendon showed that it may improve elbow flexion posture and active elbow extension in patients with flexion deformity in cerebral palsy.

References: Reference 1: Mital MA. Lengthening of the elbow flexors in cerebral palsy. J Bone Joint Surg Am. 1979;61(4):515-522. Reference 2: Manske PR, Langewisch KR, Strecker WB, Albrecht MM. Anterior elbow release of spastic elbow flexion deformity in children with cerebral palsy. J Pediatr Orthop. 2001;21(6):772- 777. Reference 3: Carlson MG, Hearns KA, Inkellis E, Leach ME. Early results of surgical intervention for elbow deformity in cerebral palsy based on degree of contracture. J Hand Surg Am. 2012;37(8):1665-1671. Reference 4: Van Heest AE, House JH, Cariello C. Upper extremity surgical treatment of cerebral palsy. J Hand Surg Am. 1999;24(2):323-330. Reference 5: Dy CJ, Pean CA, Hearns KA, Swanstrom MM, Janowski LC, Carlson MG. Long-term results following surgical treatment of elbow deformity in patients with cerebral palsy. J Hand Surg Am. 2013;38(12):2432-2436.

♦ No relevant financial relationships to disclose

E-poster 33: Gap Reduction by Transposition for High Ulnar Nerve Lesions- Which Method is Best?

Category: Treatment, Surgical Technique, Anatomy Keyword: Elbow and Forearm, Nerve N/A - Not a clinical study

♦ Imran KChoudhry, MD ♦ Zhongyu J. Li, MD ♦ Dan N Bracey, MD ♦ Ian D Hutchinson, MD

Hypothesis: Intramuscular transposition of the ulnar nerve provides the largest gap reduction when repairing high ulnar nerve lesions as compared to subcutaneous and submuscular transposition.

Methods: Six fresh frozen human adult upper extremity cadaveric specimens were thawed to room temperature and an extensile posteromedial elbow incision was made to expose the ulnar nerve. We measured a point 10 cm proximal to the medial epicondyle along the course of the ulnar nerve while keeping the elbow in neutral position (30 degrees of elbow flexion). A k-wire was used to pin the nerve in place by securing the pin through the nerve and humerus. The nerve was also secured in a similar fashion to the ulna 10 cm distal to the medial epicondyle. A thick suture was then used to mimic the exact course of the nerve from the humeral to the ulnar pin. A marker was used to mark the exact point where the suture reached each pin. The distance between these 2 points was measured as the true distance the nerve traveled to get from the humeral pin to the ulnar pin (Fig 1). The same methodology was employed with the elbow in varying degrees of elbow flexion as measured using a goniometer (0, 30, 45, 60, and 90) and after each transposition method (subcutaneous, intramuscular, and submuscular in that order)

Results: Our results demonstrated that transposing the ulnar nerve reduced the repair gap required to bypass the elbow regardless of transposition technique. When comparing individual techniques however, we found that the greatest benefit was achieved by intramuscular transposition followed by submuscular and lastly subcutaneous [Fig. 2]. Maximum gap reduction was achieved using intramuscular transposition technique with the elbow in 90 degrees of flexion. Interestingly, we noted that a subcutaneous transposition actually increases the repair gap when the elbow is in an extended position.

Summary Points: • Transposition of the ulnar nerve can produce up to 25 mm of gap reduction with the elbow in 90 degrees of flexion for nerve repair. • Transposition of the nerve in the intramuscular position as compared to the subcutaneous and submuscular positions provides the greatest amount of gap reduction and allows a favorable bed for the nerve to recover in. • A subcutaneous transposition can increase gap and strain on the nerve repair when the elbow is in the extended position.

References: Reference 1: Abrams RA, Fenichel AS, Callahan JJ, et al. The role of ulnar nerve transposition in ulnar nerve repair: A cadaver study. J Hand Surg Am. 1998;23A(2):244-249 Reference 2: Williams CS, Abrahamsson SO, Shea M, et al. Biomechanical effects of operative nerve mobilization and transposition in a canine ulnar model. J Hand Surg Am. 1997;22A(2):193- 199 Reference 3: Tsugino A, Itoh Y, Hayashi K. Excursion of the ulnar nerve at the elbow following epicondylectomy or transposition. J Hand Surg Br. 1996;21B(2):255-256 Reference 4: Grewal R, Varitmidis SE, Vardakas G, et al. Ulnar nerve elongation and excursion in the cubital tunnel after decompression and anterior transposition. J Hand Surg Br. 2000;25B(5):457-460 Reference 5: Sunderland IR, Brenner MJ, Singham J, Rickman SR, Hunter DA, Mackinnon SE. Effect of tension on nerve regeneration in rat sciatic nerve transection model. Ann Plast Surg. 2004;53:382–7 Reference 6: Wall EJ, Kwan MK, Rydevik BL, Woo SL, Garfin SR. Stress relaxation of a peripheral nerve. J Hand Surg Am. 1991 Sep;16(5):859-63 Reference 7: Millesi H. Factors affecting the outcome of peripheral nerve surgery. Microsurgery. 2006;26(4):295-302

♦ No relevant financial relationships to disclose

E-poster 34: Combined Elbow Release and Humeral Rotational Osteotomy in Arthroygryposis

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Elbow and Forearm, Shoulder and Arm, Congenital and Pediatric Problems Level 3 Evidence

♦ Rey N Ramirez, MD ♦ Dan A Zlotolow, MD ♦ Scott H Kozin, MD ♦ Dominic T Leonardelli, MD

Hypothesis: Surgical procedures to improve function in patients with arthrogryposis commonly include elbow releases to improve elbow flexion and humeral rotational osteotomies to improve external rotation. Joint releases are commonly followed by occupational therapy, whereas osteotomies are commonly immobilized after surgery. These procedures are typically done as separate procedures. At our institution we have combined these two procedures in order to minimize the number of surgeries. We hypothesize that patients with combined procedures will have similar results to patients who are staged.

Methods: All patients at our institution from 2001-2013 that were treated by elbow release (triceps lengthening, posterior capsulotomy, and ulnar nerve transposition) for arthrogryposis were reviewed retrospectively. Patients were excluded with less than six months of follow-up. Data collected included preoperative and postoperative elbow flexion and extension as well as complications.

Results: A total of 43 patients fulfilled the inclusion criteria. 14 patients underwent elbow release in combination with humeral rotational osteotomy and 29 patients were treated by elbow release alone. Preoperative arc of motion was 39.4º in the combined group (flexion-extension arc 5.7º to 45.2º) and 28.4º in the release only group (flexion-extension arc 2.1º to 30.5º). Postoperative arc of motion was 52.5º in the combined group (flexion-extension arc 45.0º to 93.9º) and 64.23º in the release only group (flexion-extension arc 33.5º to 96.4º). The postoperative arc of motion was significantly different between the two groups (p=0.03). The difference was largely due to loss of extension in the patients treated with combined humeral rotational osteotomy and elbow release. Three patients with combined procedures developed hardware complications including one case of delayed union and two of periprosthetic fracture.

Summary points: - Elbow release improves not only the amount of flexion but also increases the total arc of motion in patients with arthrogryposis - Combining rotational osteotomy with elbow release decreases the gains in total arc of motion, primarily due to loss of passive elbow extension - Delayed union and periprosthetic fracture are of concern when performing humeral osteotomy in combination with elbow release in patients with arthrogryposis

References: Reference 1: Van Heest a, Waters PM, Simmons BP. Surgical treatment of arthrogryposis of the elbow. J Hand Surg Am. 1998; 23(6):1063–70. Reference 2: Van Heest A, James M a, Lewica A, Anderson K a. Posterior elbow capsulotomy with triceps lengthening for treatment of elbow extension contracture in children with arthrogryposis. J Bone Joint Surg Am. 2008; 90(7):1517–23. Reference 3: Bamshad M, Van Heest AE, Pleasure D. Arthrogryposis: a review and update. J Bone Joint Surg Am. 2009; 91 Suppl 4:40–6. Reference 4: Ezaki M. An Approach to the Upper Limb in Arthrogryposis. J Pediatr Orthop. 2010;30(2):S57–S62 Reference 5: Kozin SH, Kay SP, Griffin JR, Ezaki M. chapter 43 - Congenital Contracture. In: Wolfe SW, Pederson WC, Hotchkiss RN, Kozin SH, eds. Green’s Operative Hand Surgery. 6th ed. Philadelphia: Elsevier Inc.; 2010:1435–1457 Reference 6: Zlotolow D, Kozin S. Posterior Elbow Release and Humeral Osteotomy for Patients With Arthrogryposis. J Hand Surg Am. 2012;37(5):1078–1082.

♦ No relevant financial relationships to disclose

E-poster 35: Long Term Outcomes of Four Corner Arthrodesis - Minimum Ten Year Follow-Up

Category: Prognosis/Outcomes Keyword: Hand and Wrist Level 4 Evidence

♦ Chirag M. Shah, MD ♦ Thomas R. Kiefhaber, MD ♦ Andrew D. Markiewitz, MD ♦ Peter J. Stern, MD

Hypothesis: Four corner arthrodesis is a motion-sparing procedure for degenerative disorders of the wrist. We hypothesized that the long-term outcomes of patients who had achieved radiographic four corner fusion in the short-term using validated outcome measures after a minimum ten year follow-up would uphold the longevity of the procedure.

Methods: Fifteen patients who underwent four corner arthrodesis at an average age of 43 years were evaluated at minimum follow-up of 10 years (average, 17 yrs). Patients returned for radiographic and clinical evaluation and the visual analog pain and function score (VASp and VASf) along with the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire were used for subjective outcome assessment. Success of treatment was defined as resolution or improvement of symptoms with preserved upper extremity function, obviating the need for further surgical intervention.

Results: Fourteen of the 15 (93%) surgeries were successful at final follow-up. Twelve patients (80%) were very satisfied and two patients (13%) were satisfied. Thirteen patients (87%) returned back to their previous employment. Mean flexion/extension arc was 66° and grip/pinch were 87% and 93% of the contralateral side respectively. QuickDASH averaged 15.4 (0-38.6), VASp averaged 1.6 (0-5.4), and VASf averaged 2.3 (0-5.7). Final radiographic follow-up showed no arthrosis in 8 wrists (53%), mild arthrosis in 3 wrists (20%), and moderate arthrosis in 4 wrists (27%). All patients with arthrosis were asymptomatic.

Summary Points: 1. Four corner arthrodesis is a durable surgical procedure in the long term. 2. Those patients that obtain adequate fusion have a 93% satisfaction rate with limited functional impairments at greater than 10 years. 3. Almost half of patients develop mild to moderate radiolunate arthrosis however remain asymptomatic. 4. We recommend the use of four corner arthrodesis for the treatment of wrist arthritis in young active individuals.

♦ No relevant financial relationships to disclose

E-poster 36: Does Giving Patients Pre-Operative Hand Therapy Instructions Affect the Need for Post-Operative Hand Therapy?

Category: Treatment, Therapy/Rehabilitation, Prognosis/Outcomes, Patient Education Keyword: Hand and Wrist Level 3 Evidence

♦ Nicholas MCaggiano, MD ● Kristofer Matullo, MD

Hypothesis: Providing pre-operative occupational hand therapy instructions to patients undergoing small soft tissue procedures (carpal tunnel release, trigger finger release or de Quervain’s release) will lead to a decreased need for post-operative therapy.

Methods: The outpatient records of 457 patients who had undergone elective carpal tunnel release, trigger finger release or de Quervain’s release were retrospectively reviewed. Patients undergoing surgery between July 1, 2010 and June 30, 2011 did not receive pre-operative occupational hand therapy instructions. Those undergoing surgery from July 1, 2011 and June 30, 2012 did receive pre-operative hand therapy instructions. All patients were instructed to use their hand normally with a 10 pound lifting restriction. Those given instructions were given a “six pack” of hand exercises to be completed three times a day. The first post-operative office note was reviewed and the determination for further formal hand therapy was noted. A medical history of diabetes mellitus and use of tobacco were also recorded to determine possible effects on outcome. Chi- squared tests were used to determine the effect of pre-operative instructions on the need for post-operative therapy, as well as to determine the effects of diabetes and smoking.

Results: A total of 518 hands in 457 patients met inclusion criteria. 246 hands (209 patients) out of the 518 hands examined (47%) were not given any pre-operative therapy instructions. 272 hands (248 patients) (53%) were given hand therapy instructions before surgery. Post-operative formal therapy was required in 62 of the 246 (25%) of patients who did not receive pre-operative therapy and 80 of the 272 (29%) patients who received pre-operative therapy (p=0.28). History of diabetes mellitus and smoking status did not have an affect on the significance of this relationship. There were 96 of 518 hands in patients with diabetes (19%). 10 of 37 (27%) of diabetic hands that hand no pre-operative instruction and 18 of 59 (31%) diabetic hands that received pre-operative instruction required post-operative therapy (p=0.71). Patients who actively smoke compromised 63 of 518 hands (12%). Post-operative therapy was required in 9 of 31 (29%) hands with no pre-operative instruction vs. 10 of 32 (31%) hands with pre-operative instruction (p=0.85). Summary Points: • Providing occupational hand therapy instructions to patients prior to surgery has no effect on the need for post-operative therapy. • Medical comorbidities, such as diabetes mellitus and smoking, also have no effect on the need for post-operative therapy in patients receiving small soft tissue procedures.

References: Reference 1: Amadio, P. C., et al. (1996). "Outcome assessment for carpal tunnel surgery: the relative responsiveness of generic, arthritis-specific, disease-specific, and physical examination measures." J Hand Surg Am 21(3): 338-346. Reference 2: Chammas, M., et al. (1995). "Dupuytren's disease, carpal tunnel syndrome, trigger finger, and diabetes mellitus." J Hand Surg Am 20(1): 109-114. Reference 3: Cook, A. C., et al. (1995). "Early mobilization following carpal tunnel release. A prospective randomized study." J Hand Surg Br 20(2): 228-230. Reference 4: Lozano-Calderon, S., et al. (2008). "The quality and strength of evidence for etiology: example of carpal tunnel syndrome." J Hand Surg Am 33(4): 525-538. Reference 5: McAuliffe, J. A. (2010). "Tendon disorders of the hand and wrist." J Hand Surg Am 35(5): 846-853; Reference 6: Papanicolaou, G. D., et al. (2001). "The prevalence and characteristics of nerve compression symptoms in the general population." J Hand Surg Am 26(3): 460-466. Reference 7: Pomerance, J. and I. Fine (2007). "Outcomes of carpal tunnel surgery with and without supervised postoperative therapy." J Hand Surg Am 32(8): 1159-1163 Reference 8: Thomsen, N. O., et al. (2009). "Clinical outcomes of surgical release among diabetic patients with carpal tunnel syndrome: prospective follow-up with matched controls." J Hand Surg Am 34(7): 1177-1187.

● Consulting Fee: DePuy Synthes (Matullo) ● Contracted Research: (Matullo)

♦ No relevant financial relationships to disclose

E-poster 37: Treatment of Proximal Pole Scaphoid Nonunion with Capsular-Based Vascularized Distal Radius Graft.

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist Level 4 Evidence

♦ Dean G Sotereanos, MD ♦ Loukia K Papatheodorou, MD

Hypothesis: Treatment of proximal pole scaphoid nonunion with avascular necrosis is a challenging issue. We reviewed the results of 53 patients with proximal pole scaphoid nonunion, 41 with avascular necrosis, treated with a capsular-based vascularized distal radius graft.

Methods: Thirty-nine male and fourteen female with symptomatic nonunion at the proximal pole of the scaphoid were included in this study. Mean patient age was 28 years (range, 19-43). The vascularized bone graft was harvested from the distal aspect of the dorsal radius and was attached to a capsular flap of the dorsal wrist capsule. The graft was vascularized by the artery of the fourth extensor compartment. After fixation of the scaphoid with a Herbert screw, the graft was inserted press-fit into a dorsal trough across the nonunion site. Supplementary fixation of the graft with a micro suture anchor into the scaphoid was used in 34 patients. At follow-up each patient was evaluated with physical and radiographic examination.

Results: At a mean time of 13.6 weeks (range, 6-24) after surgery, solid union was achieved in 46 of 53 patients (87%). Six patients had persistent non-union and one fibrous union as determined by CT scan. Forty of the patients with solid bone union were completely pain free and six complained of slight pain with strenuous activities. Wrist flexion and extension were improved postoperatively. Grip strength was improved significantly by a mean of 66%. The mean modified Mayo wrist score significantly improved from 43 to 84. No arthritic changes were noted at the dorsal ridge of the radius. No donor site morbidity was observed.

Summary Points: • Capsular-based vascularized distal radius graft is a simple technique • Eliminates the need for dissection of small caliber pedicle • No microsurgical anastomoses • No donor site morbidity • Results compare favorably to those of pedicled or free vascularized grafts

References: Reference 1: Sotereanos DG, Darlis NA, Dailiana ZH, Sarris IK, Malizos KN. A capsular-based vascularized distal radius graft for proximal pole scaphoid pseudarthrosis. J Hand Surg Am. 2006 Apr;31(4):580-7. Reference 2: Derby BM, Murray PM, Shin AY, Bueno RA, Mathoulin CL, Ade T, Neumeister MW. Vascularized bone grafts for the treatment of carpal bone pathology. Hand (N Y). 2013 Mar;8(1):27-40. Reference 3: Venouziou AI, Sotereanos DG. Supplemental graft fixation for distal radius vascularized bone graft. J Hand Surg Am. 2012 Jul;37(7):1475-9. Reference 4: Malizos KN, Dailiana ZH, Innocenti M, Mathoulin CL, Mattar R Jr, Sauerbier M. Vascularized bone grafts for upper limb reconstruction: defects at the distal radius, wrist, and hand. J Hand Surg Am. 2010 Oct;35(10):1710-8.

♦ No relevant financial relationships to disclose

E-poster 38: The Use of Pre-Operative Antibiotic Prophylaxis for Elective Soft Tissue Hand Surgery by Members of the American Society for Surgery of the Hand

Category: Treatment, Medical/Legal Keyword: Hand and Wrist, General Principles N/A - Not a clinical study

♦ Jason Stuart Pruzansky, MD

Hypothesis: Reducing surgical site infection (SSI) with prompt administration of peri-operative antibiotics is gaining more resources and attention by hospitals and insurers. However, recent data from large studies has shown that clean, elective, soft tissue hand surgery cases may not benefit from the administration of pre-operative antibiotics. We sought to analyze and understand the use of antibiotic prophylaxis by hand surgeons.

Methods: We distributed an online survey by email to active practicing surgeons of the American Society for Surgery of the Hand. The survey had up to seven questions addressing demographic characteristics and when and why antibiotics are used.

Results: The results from the 615 responding hand surgeons demonstrate that 43% routinely use antibiotic prophylaxis, and of those surgeons, 56% do so for defensive reasons. Only 5% of surgeons who do not routinely use antibiotics would add them for a patient who smokes, but nearly 43% would add them for a patient with diabetes. 57% of all respondents would favor formal clinical guidelines for the use of pre-operative antibiotics. Demographic characteristics affected answers, as 20% more American surgeons routinely use antibiotics compared to non- American surgeons. Furthermore, surgeons in the Northeast and Pacific regions of the United States were approximately twice as likely to report using antibiotics for defensive reasons compared to other locations. Orthopaedic surgeons were more likely to use antibiotics than plastic or general surgeons, while older surgeons were less likely to than younger.

Summary Points: Wide variability exists among hand surgeons, partly due to demographic factors. Medico-legal concerns remain an influential factor in deciding whether to use antibiotic prophylaxis for elective hand surgery. Further implementation of evidence-based medicine can be pursued

References: Reference 1: Bykowski MR, Sivak WN, Cray J, et al. Assessing the impact of antibiotic prophylaxis in outpatient elective hand surgery: a single-center, retrospective review of 8,850 cases. J Hand Surg Am. 2011;36:1741-1747. Reference 2: Tosti R, Fowler J, Dwyer J, et al. Is antibiotic prophylaxis necessary in elective soft tissue hand surgery? Orthopaedics. 2012;35(6):829-833. Reference 3: Harness NG, Inacio MC, Pfeil FF, et al. Rate of infection after carpal tunnel release and effect of antibiotic prophylaxis. J Hand Surg Am. 2010;35:189-196. Reference 4: Miller RA, Sampson NR, Flynn JM. Prevalence of defensive orthopaedic imaging: prospective practice audit in Pennsylvania. J Bone Joint Surg Am. 2012;94:e18(1-6). Reference 5: Sethi MK, Obremskey WT, Navitividad H, et al. Incidence and costs of defensive medicine among orthopaedic surgeons in the United States: a national survey study. Am J Orthop. 2012;41(2):69-73.

Figure 1: “Do you routinely use pre-operative antibiotics for the following scenario: A patient without additional risk factors for infection undergoes elective soft tissue hand surgery that lasts less than 2 hours?”

Figure 2: For all respondents who routinely use antibiotic prophylaxis, “Do you routinely use pre- operative antibiotics for these cases due to “defensive medicine” reasons?”

♦ No relevant financial relationships to disclose

E-poster 39: Regeneration of tendon-bone junction using a cell sheet composed human tendon derived cells

Category: Basic Science Keyword: Hand and Wrist, Shoulder and Arm N/A - Not a clinical study

♦ Yoshifumi Harada, MD ♦ Yutaka Mifune, MD ♦ Atsuyuki Inui, MD ♦ Issei Nagura, MD ♦ Takako Kanatani, MD ♦ Takeshi Kokubu, MD

Hypothesis: The treatment for tendon avulsion, such as a tendinous mallet finger, has been controversial. Biological regeneration of tendon-bone junction is ultimate goal of tendon tissue engineering. We previously reported the cells from tendon have a potential of self-proliferation and multilinage differentiation. We hypothesize that the cell sheet technology is one of the attractive methods to deliver cells and enhance regeneration of the bone-tendon junction. We developed a cell sheet composed human tendon derived cells and examined its therapeutic effects using a tendon injury model in rats.

Methods: Tendon derived cells were isolated from human rotator cuff tissue, and a cell sheet was made using temperature-responsive culture plates. Infraspinatous tendons in immunodefficiency rats were resected bilaterally. In right shoulders, infraspinatous tendons were repaired by transoseous repair and covered with the cell sheet (sheet group), while infraspinatous tendons in the left were repaired in the same way without a cell sheet (control). Immunofluorescence staining was performed at 4 weeks after the operation to assess angiogenesis (Isolectin B4), fibro-cartilage regeneration (type II collagen), and angiogenic differentiation from the transplanted cells (human specific CD31) at tendon-bone junction. Biomechanical test was performed at 8weeks.

Results: In the sheet group at 4 weeks, numerous chondrocytes at the repaired sites were confirmed by Toluidine blue staining. In immunofluorescence staining, higher numbers of type II collagen or Isolectin B4 positive cells were seen in the sheet group compared to the control. Moreover, human specific CD31 positive cells were detected in the sheet group. In the mechanical testing, the sheet groups showed a significant higher tensile strength than the control at 8 weeks.

Summary Points: Our results indicated that the tendon derived cell sheet could promote fibro-cartilage regeneration and angiogenesis at tendon-bone junction, with superior mechanical strength compared to the control. The treatment for tendon avulsion using cell sheet could be a promising strategy for tendon tissue engineering.

♦ No relevant financial relationships to disclose

E-poster 40: Prevention of perineural adhesion makes functional recovery of the chronic nerve compression syndrome

Category: Basic Science Keyword: Nerve N/A - Not a clinical study

♦ Katsuyuki Iwatsuki, MD, PhD ♦ Hideki Urano, MD ♦ Tetsuro Ohnisi, MD ♦ Michiro Yamamoto, MD, Ph.D ♦ Nobuyuki Endo, Mr. ♦ Hitoshi Hirata, MD

Hypothesis: Adhesion and perineural scarring mainly cause treatment failure after peripheral nerve surgery. Even though numerous operative techniques have developed to prevent or reduce the incidence and severity of perineural scarring, these meticulous surgical techniques cannot completely prevent the development of postoperative adhesions. We have developed a novel sodium carboxymethylcellulose (CMC)-derived hydrogel in which phosphatidylethanolamine (PE) was introduced into the carboxyl groups of CMC. Our hypothesis is that prevention of perineural adhesion enhances functional recovery of the chronic nerve compression syndrome. We confirmed the effects of the hydrogel on functional recovery after nerve decompression.

Methods: We used a rat model of chronic nerve compression with silicon tube in sciatic nerve. After tube removal postoperatively 3 months, rats were divided into 3 groups (each group: n=6), sham, administration of CMC-PE and control groups. Rats in sham group underwent only skin incision twice. Biomechanical analysis to assess perineurial adhesion, electrophysiological evaluation of motor nerve conduction velocity (MCV), wet muscle weight measurements (tibialis anterior), and histological evaluation were performed at 1, 2 and 3 months after removal of silicone tube. Morphometric analysis were also performed at 1, 2 and 3 months after removal of silicone tube. The specimens were stained with toluidine blue and axons were morphometrically analyzed using computer-assisted image analysis.

Results: Biomechanical analysis showed breaking strength was significantly higher in the control group than in the sham and CMC-PE groups. The control group showed a significantly lower percentage of wet muscle weight than the sham and CMC groups. Electrophysiological evaluation revealed that MCVs were significantly slower in the control and CMC groups than in the sham group, and MCV in the control group was significantly slower than that of the CMC-PE group (fig.1). Larger scar areas surrounding nerve were confirmed in the control group than in the CMC-PE group. While severe adhesion was confirmed between nerves and surrounding muscles in the control group, the CMC-PE group had nerves surrounded by loose connective tissue. Morphometric analysis showed that in the CMC-PE group, many thick axons existed even at one month and their abundance ratio increased at much faster pace than control group throughout the experimental period (fig. 2).

Summary Points: These results suggest that the CMC-PE hydrogel enhanced axonal recovery after chronic nerve compression by reducing mechanical stress caused by postoperative scarring.

References: Reference 1: Ohsumi H, Hirata H, Nagakura T, Tsujii M, Sugimoto T, et al. (2005) Enhancement of perineurial repair and inhibition of nerve adhesion by viscous injectable pure alginate sol. Plast Reconstr Surg 116: 823-830. Reference 2: Ikeda K, Yamauchi D, Osamura N, Hagiwara N, Tomita K (2003) Hyaluronic acid prevents peripheral nerve adhesion. Br J Plast Surg 56: 342-347 Reference 3: Dam-Hieu P, Lacroix C, Said G, Devanz P, Liu S, et al. (2005) Reduction of postoperative perineural adhesions by Hyaloglide gel: an experimental study in the rat sciatic nerve. Neurosurgery 56: 425-433. Reference 4: Yamamoto M, Endo N,Ito M, Okui N, Koh S, et al. (2010) Novel polysaccharide- derived hydrogel prevents perineural adhesions in a rat model of sciatic nerve adhesion. J Orthop Res 28: 284-288.

♦ No relevant financial relationships to disclose

E-poster 41: Treatment of Cystic Type Scaphoid Fractures with Acutrak Screws: Is Bone Grafting Necessary?

Category: Treatment Keyword: Hand and Wrist Level 4 Evidence

♦ Naoki Osamura, MD ♦ Kazuo Ikeda, MD

Hypothesis: The necessity of bone grafting in the treatment of cystic type scaphoid fractures is still controversial. We report the treatment of cystic type scaphoid fractures without bone grafting using Acutrak screws.

Methods: We used our original classification system of scaphoid fractures based on radiographic findings, such as linear type, cystic type and sclerotic or displaced type. The length of time before surgery did not affect the classification. Linear and cystic types did not have any displacement more than 2 mm. If the fracture line had a sclerotic zone thicker than 1 mm, it was classified as sclerotic or displaced type. A retrospective review was performed in 27 patients who were classified into cystic type and were treated without bone grafting using Acutrak screws. Percutaneous screw fixation was performed using the volar approach for waist fracture and the dorsal approach for proximal pole fracture. Mean age was 24 years (range 14-75). The fracture was located in waist for 21 cases and proximal pole for 6 cases. Mean time before surgery was 5.8 months (range 1- 60).

Results: Bone union was achieved all cases in waist fracture. There were 2 failures in 6 cases in proximal pole fracture. Two failure cases were treated over 5 years after the injury and their volar flexion in wrist were restricted before surgery. Therefore, the Acutrak screw was not inserted from the apex of the proximal pole and along the midline axis of the scaphoid. We believe bone unions were not achieved in 2 failure cases as rigid fixations were not obtained because of unsatisfied screw positioning.

Summary Points: ·Basically, bone grafting was not needed for cystic type scaphoid fractures based on our original classification. ·We obtained bone union in 21 cases (100%) of waist fracture and 4 cases (67%) of proximal pole fracture. ·Percutaneous screw positioning was the most important factor to achieve bone union for cystic type scaphoid fractures, especially in proximal pole fracture with the restricted wrist motion. ·The Acutrak screw was a reliable instrument to obtain a rigid stability for cystic type scaphoid fractures.

♦ No relevant financial relationships to disclose

E-poster 42: A novel myoelectric prostheses with a tacit learning program

Category: Basic Science Keyword: Elbow and Forearm N/A - Not a clinical study

♦ Katsuyuki Iwatsuki, MD, PhD ♦ Shintaro Oyama, MD ♦ Fady Alnajar, Dr.Eng ♦ Shingo Shimoda, Ph.D. ♦ Michiro Yamamoto, MD, Ph.D ♦ Hitoshi Hirata, MD

Hypothesis: Learning in human beings occurs in two ways, with conscious awareness and subliminally. The capability of adapting to unknown environmental situations is one of the most salient features of biological regulation. This capability is ascribed to the learning mechanisms of biological regulatory systems that are totally different from the current artificial machine-learning paradigm. We proposed a learning method termed tacit learning that embodies the features of biological systems. Owing to tacit knowledge, one can perform complex motions involving many muscles. Tacit learning is a novel learning scheme based on the principle of biological regulation to create appropriate behaviors adapted to the environment. The tacit learning system has already been introduced in humanoid robots with some degree of self-sufficiency. We have developed a myoelectric upper limb prosthesis equipped with this tacit learning system to auto-regulate forearm rotation in response to the upper extremity movement pattern. Our hypothesis is that this prosthesis improves operability and reduces physical burden.

Methods: Forearm amputees were tested on a series of tasks requiring forearm rotation (Fig.1). They were fitted with the tacit learning prosthesis. Serial changes in the rotation angle of the prosthesis were monitored. A series of six motion capture cameras were used to capture lightweight markers placed on various points of the body, and the system energy and compensatory rotation at the shoulder were calculated.

Results: Eight patients (7 men, 1 woman) were registered. The mean age of the patients was 45.6 (range, 29–74) years. Among the amputated hands, there were seven right hands and one left hand. The compensatory shoulder rotation angle decreased by 21.0° on average (Fig.2), while the prosthetic arm support angle increased by 33.7° at the last trial. Motion capture data showed that the patient’s energy consumption could be reduced with this system. The energy consumption after learning was calculated to be about 60% of that before learning.

Summary Points: The notion of tacit learning has been introduced to develop artificial control systems for creating artifacts with high adaptability comparable with living organisms. We equipped a conventional myoelectric hand with a newly developed forearm rotation unit, which is auto-regulated by the tacit learning program. The experimental results demonstrated the high adaptability of tacit learning. This system learns the patients’ compensatory movement pattern and automatically produces forearm rotation to reduce the physical burden on the patient.

References: Reference 1: Shingo Shimoda, Yuki Yoshihara, and Hidenori Kimura,Adaptability of Tacit Learning in Bipedal Locomotion. IEEE TRANSACTIONS ON AUTONOMOUS MENTAL DEVELOPMENT, VOL. 5, NO. 2, JUNE 2013 Reference 2: Shingo Shimoda and Hidenori Kimura, Biomimetic Approach to Tacit Learning Based on Compound Control. IEEE TRANSACTIONS ON SYSTEMS, MAN, AND CYBERNETICS—PART B: CYBERNETICS, VOL. 40, NO. 1, FEBRUARY 2010

Figure 1

Table 1

♦ No relevant financial relationships to disclose

E-poster 43: First rib abnomaly in thoracic outlet syndrome for risk factor of subclavian artery aneurysm with literature review.

Category: Evaluation/Diagnosis, Treatment, Anatomy Keyword: Congenital and Pediatric Problems, Diseases and Disorders Level 4 Evidence

♦ Takuya Yokoi, MD ♦ Mitsuhiro Okada, MD, PhD ♦ Kiyohito Takamatsu, MD, PhD ♦ Takuya Uemura, MD, PhD ♦ Mikinori Ikeda, MD ♦ Hiroaki Nakamura, MD, PhD

Hypothesis: It may be possible that thoracic outlet syndrome with first rib abnomaly may cause symptom involving the subclavian artery and require emergent interventions when circulation of the subclavian artery is occluded.

Methods: We retrospectively reviewed 9 cases surgically treated with diagnosis of TOS. Three were male, and 6 were female. The average age at the time of surgery was 35 years (range, 17 to 45 years). Cases requiring emergent interventions for symptoms of the subclavian artery were investigated; physical symptoms, preoperative plain radiography or computed tomography, time interval between the onset of symptoms to emergent interventions. Also we reviewed available literatures describing ischemic complication and bony malformation in TOS.

Results: Two of 9 cases required emergent interventions. Both cases had progressively increasing severe pain, and paler, pulseless and decreased temperature of the affected upper extremity, although in one case neurological examinations were normal. Preoperative plain radiography or computed tomography in the 2 cases showed abnormal first rib lacked the anterior half and assimilated with the second rib. The mean time interval between the onset of symptoms to emergent interventions was 4 months. Before resection of the abnormal first rib, Both cases required anticoagulant therapy, and one of them needed endvascular therapy with embolectomy and stent insertion. Sporadic reports over several decades also report the incidence of vascular symptoms from compression of the subclavian artery caused by abnormal first rib and the necessity of prompt treatment to avoid limb-threatening ischemic changes to upper extremity.

Summary Points: First rib anomaly showing lack of the anterior half and assimilation with the second rib causes emergent vascular events in TOS. Symptomatic TOS with such anomaly requires intensive observation and prompt treatment.

References: Reference 1: Congenital malformations of the first thoracic rib; a cause of brachial neuralgia which simulates the cervical rib syndrome. Surg Gynecol Obstet. 1945 Dec;81:643-59. Reference 2: The rudimentary first rib. A cause of thoracic outlet syndrome with arterial compromise. Arch Surg. 1989 Sep;124(9):1090-2. Reference 3: Arterial complications of thoracic outlet syndrome. Am Surg. 2009 Mar;75(3):235-9. Reference 4: Arterial thoracic outlet syndrome. Hand Clin. 2004 Feb;20(1):107-11

Figure 1

Figure 2

♦ No relevant financial relationships to disclose

E-poster 44: In Vitro Effects of PRP on Rat Adipoderived Stem Cells in Tendon Hydrogel

Category: Treatment, Basic Science Keyword: Hand and Wrist, Diseases and Disorders N/A - Not a clinical study

♦ Christopher S Crowe, BS ♦ Grace J Chiou, MD ♦ Rory McGoldrick, MBBS, MBA ♦ Kenneth Hui, BA ♦ Hung Pham, BS ♦ James Chang, MD

Hypothesis: Tendon hydrogel is a promising new injectable substance that has been shown to improve repair strength after tendon injury. We hypothesize that PRP augments the proliferation and migration of rat adipoderived stem cells (ASCs) in tendon hydrogel in vitro.

Methods: PRP was processed and activated using previously described techniques. Rat ASCs were plated at a density of 1000 cells/well and covered with various concentrations (5%, 10%, and 20%) of plasma, plasma supplemented with growth factors, or activated PRP (aPRP), in culture media. Rat ASCs were also seeded into human tendon hydrogel at an initial density of 100,000 cells/well. The cell-seeded hydrogel was then mixed with the concentrations of the conditions listed above (with both activated, aPRP, and unactivated PRP, uPRP). Proliferation of ASCs in culture media and hydrogel was measured by MTS colorimetric assay. To assess migration, an ORIS assay was employed. Tendon hydrogel was used to coat the migration surface. Cells were plated and subsequently covered with media containing 10% plasma, plasma supplemented with growth factors, activated PRP, or serum free media with bovine serum albumin (BSA). Migration was assessed by microplate reader at 12, 24, 36, and 48 hours by Syto Green fluorescent stain. To compare conditions an unpaired T-test was used. Statistical significance was set at p <0.05.

Results: At 10% volume in culture media, activated PRP augmented proliferation to a greater extent compared to plasma and plasma supplemented with growth factor (O.D. 1.18 vs. 0.75 vs. 0.98 respectively; both p < 0.05). At 10% in tendon hydrogel, activated PRP was superior to plasma (O.D. 1.19 vs. 0.85, respectively; p = 0.01) but did not augment proliferation to the extent that plasma supplemented with growth factors did (O.D. 1.19 vs. 1.56, respectively; p = 0.005). Unactivated PRP caused proliferation greater than plasma, suggesting that tendon hydrogel is an intrinsic activator of platelets. Lastly, activated PRP was demonstrated to enhance the migration of ASCs across all time points with values converging at 48 hours as the migration area became saturated (At 36 hours: PRP 1.88, Plasma 1.51, Plasma + GF 1.80, BSA 1.43).

Summary Points: •In culture media and human tendon hydrogel alike, PRP greatly augmented cellular proliferation. •PRP also enhanced the migration of ASCs on tendon hydrogel coated plates. •Because tendon healing consists of cell migration and proliferation, this study suggests that the addition of PRP to hydrogel may be useful in accelerating tendon healing in vivo.

References: Reference 1: Farnebo SJ, Woon CY, Schmitt T, Joubert LM, Kim M, Pham H, and Chang J. Design and characterization of an injectable tendon hydrogel: a scaffold for guided tissue regeneration in the musculoskeletal system. Tissue Eng Part A 2013 [Epub ahead of print]. Reference 2: Ahmad Z, Howard D, Brooks RA, Wardale J, Henson FM, Getgood A, and Rushton N. The role of platelet rich plasma in musculoskeletal science. JRSM Short Rep 2012;3(6):40. Reference 3: Amable PR, Carias RB, Teixeira MV, da Cruz Pacheco I, Correa do Amaral RJ, Granjeiro JM, and Borojevic R. Platelet-rich plasma preparation for regenerative medicine: optimization and quantification of cytokines and growth factors. Stem Cell Res 2013;4(3):67. Reference 4: Uysal CA, Tobita M, Hiko H, and Mizuno H. Adipose-derived stem cells enhance primary tendon repair: Biomechanical and immunohistochemical evaluation. J Plast Reconstr Aesthet Surg 2012;65(12):1712-1719. Reference 5: Raghavan SS, Woon CYL, Kraus A, Megerle K, Pham H, Chang J. Optimization of human tendon tissue engineering: synergistic effects of growth factors for use in tendon scaffold repopulation. Plast Reconstr Surg. 2012;129(2):479-89.

♦ No relevant financial relationships to disclose

E-poster 45: CapFlex-PIP© - A new modular surface-gliding arthroplasty. First mid-term results

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist Level 4 Evidence

● Stephan F Schindele, MD ♦ Laurent Audigé, MVM, PhD ♦ Stefanie Hensler, MSc ♦ Miriam Marks, MS ● Daniel B Herren, MD

Hypothesis: The CapFlex-PIP© is a new modular non-cemented surface-gliding implant for PIP-arthroplasty (Figure 1) which should preserve bone stock and the collateral ligaments to provide long-term improvement in pain and function, as well as in joint axis deviation and lateral stability. Following a pilot study, a clinical register was initiated to investigate the clinical, subjective and radiographic outcomes in all patients.

Methods: Patients with primary or secondary osteoarthritis of the PIP joint were operated by three surgeons using either the volar or dorsal approach described by Chamay. Preoperatively, after 6 weeks, 3, 6 and, 12 months range of motion (ROM) of the PIP joint and grip strength were assessed. In addition the first pilot patients were examined 24-36 months after surgery. Patients rated their pain on a numeric rating scale (NRS) and filled out the quick Disabilities of the Arm, Shoulder and Hand Outcome Questionnaire (quick DASH), and the Patient Evaluation Measure (PEM), part 2. Standard ap and lateral radiographs were taken. The Wilcoxon signed-rank test was used to assess differences of the subjective and objective clinical parameters between preoperatively and at last time of follow up. Mean outcome changes with 95% confidence intervals are presented.

Results: Fifty-four patients (33 female, 21 male) with a mean age of 63.8 years (±12.4) were documented (Figure 2). The active range of motion of affected PIP joint increased slightly from 45.5° (±19.3) preoperatively to 49.8° (±21.9) after one year (p=0.18). A mean improvement of 14.9° was noted on the first 7 patients at 2-3 years. Patients reported a significant pain relief from preoperatively 7.9 (±0.4) to 1.1 (±1.5) at 12 months follow-up (p=0.018). Compared to preoperatively there was also a significant improvement in the quick DASH by 28.4 (±17.5) points from preoperatively to after one year (p=0.007). All implants remained intact over the postoperative time and no migration, no osteolysis and no implant fractures occurred. At the 2-3 years examination, 2/3 of examined patients had their longitudinal axis deviation improved to normal.

Summary Points: The use of the CapFlex PIP© implant provided overall satisfactory results one to three years after surgery in particular to lateral stability at the radial fingers. All implants showed no evidence of radiological migration. The positive subjective and clinical outcomes confirm the radiological results. Further mid- and long-term evaluations are ongoing.

● Royalty: KLSMartin (Schindele, Herren) ● Consulting Fee: DePuy-Synthes (Herren)

♦ No relevant financial relationships to disclose

E-poster 46: Fascia Wrapping Technique: A Modified Method for the Treatment of Cubital Tunnel Syndrome

Category: Surgical Technique, Anatomy Keyword: Elbow and Forearm, Nerve, Diseases and Disorders Level 4 Evidence

♦ Hyun Ho Han, MD ♦ Hye Won Kang, MD ♦ Jun Yong Lee, MD ♦ Sung-No Jung, MD,PhD

Hypothesis: Surgical treatment methods for cubital tunnel syndrome have their own advantages and disadvantages, and the preferred method differs depending on the surgeon. Variations of the anterior transposition of the ulnar nerve include subcutaneous[1], submuscular[2], intramuscular[3] and subfascial[4] methods. Presently, we introduce a modification of subfascial transposition, which is designed to facilitate nerve gliding by wrapping the nerve with fascia.

Methods: Twenty patients wrapping surgery were reviewed retrospectively.(Table 1-a) To confirm the diagnosis, the result of nerve conduction studies should be less than 50 m/s. Pre-operatively, the condition of the ulnar nerve was graded according to severity, based on Dellon’s classification.[5] Fascia wrapping was used for the surgery in all patients and post-operative outcome assessment for the patients who had surgery a year ago was based on the modified Bishop scoring system.[6] (Operative Procedure) The ulnar nerve located under the deep fascia was incised cautiously, with an incision made proximally in the distal direction. The feeding artery vessel of the nerve should be saved. Anterior transposition of the ulnar nerve was conducted. Superficial fascia belonging to the flexor pronator muscle group was elevated with a width exceeding approximately 3 cm and also elevated to a position 1–2 cm apart from the medical epicondyle origin. Then we conducted the wrapping procedure by locating the ulnar nerve over the fascia and rolling the ulnar nerve with the elevated fascia flap (Figure 1). Fixation was easy and firm because the fascia was sutured together.

Results: Their average age was 49 years (range, 33 to 68 years). Eleven patients (55%) had demonstrated intrinsic atrophy, grip strength were reduced in Seventeen patients (85%) showed positive result for Tinel's sign. All patients demonstrated abnormal finding on nerve conduction test preoperatively. Moderate to severe grade was obtained for sensory and motor tests on Dellon’s classification preoperatively (Table 1-b). The total follow-up period was 24 months. All patients demonstrated an excellent score (8~9) and good score (5~7) when evaluated with the modified Bishop scoring system (Table 1-c).

Summary Points: This method provides better immobilization than subfascial transposition, less risk of kinking or compression because the movement of nerve is performed on the same plane and has fast recovery and less adhesion due to the nerve wrapping with healthy fascia surface. Therefore, this method can be a preferable option to treat cubital tunnel syndrome.

References: Reference 1: Richmod JC, Southmayd WW. Superficial anterior transposition of the ulnar nerve at the elbow for neuritis. Clin Orthop 1982;164:42-44. Reference 2: Zemel N, Jobe FW, Yocum LA. Submuscular transposition/ulnar nerve decompression in athletes. In: Gelberman RH, ed. Operative Nerve Repair and Reconstruction Philadelphia: J.B. Lippincott, 1991:1097-1104. Reference 3: 3Kleinman WB. Anterior intramuscular transposition. In: Gelberman RH, ed. Operative Nerve Repair and Reconstruction Philadelphia: J.B. Lippincott, 1991:1069-1076. Reference 4: Teoh LC, Yong FC, Tan SH, et al. Anterior subfascial transposition of the ulnar nerve. J Hand Surg Br 2003;28(1):73-76. Reference 5: Dellon AL. Technique for successful management of ulnar nerve entrapment at the elbow. Neurosurg Clin N Am 1991;2(1):57-73. Reference 6: Kleinman WB, Bishop AT. Anterior intramuscular transposition of the ulnar nerve. J Hand Surg Am 1989;14(6):972-979.

♦ No relevant financial relationships to disclose E-poster 47: Anatomical Cadaver Study of the Hotchkiss Over-the-Top Approach to Internal Fixation for Fracture of the Coronoid Process of the Ulna

Category: Treatment, Surgical Technique, Anatomy, Basic Science Keyword: Elbow and Forearm, Nerve N/A - Not a clinical study

♦ Koji Sukegawa, MD ♦ Kazuki Kuniyoshi, MD,PhD ♦ Takane Suzuki, MD,PhD ♦ Yasufumi Ogawa, MD ♦ Keisuke Ueno, MD ♦ Hitoshi Kiuchi, MD

Hypothesis: Despite the excellent visuals and utility of Hotchkiss’ over-the-top approach to treating fracture of the coronoid process, anatomical study of the operative procedure is inadequate at present. Here, we clarified the procedure for Hotchkiss’ over-the-top approach in osteosynthesis of fracture of the coronoid process, especially in the viewpoint of positional relationship to the median nerve by conducting an anatomical study.

Methods: Twelve upper limbs from frozen cadavers were used. Elbow flexion was 30°, and forearm supination was 90°. A skin incision of 14 cm was made at the center of the medial epicondyle, after which the medial intermuscular septum was excised 5 cm and the brachial muscle elevated on the periosteum. The flexor and pronator muscle mass was divided parallel to the fibers, leaving a 15-mm span of flexor carpi ulnaris tendon attached to the epicondyle with the articular capsule exposed. Subsequently, the shortest distance from the medial epicondyle to the median nerve and the distance in the fascia dissecting direction were measured. The articular capsule was excised to expose the coronoid process, and the shortest distance from the coronoid process to the median nerve was measured. A pin was inserted from the coronoid process tip, and the final dissection length of the fascia of the pronator and flexor muscles was measured. Finally, the skin incision was extended, and the width of the attachment point of the brachial muscle on the ulna as well as the shortest distance from the proximal and distal portions of the attachment point to the median nerve were measured.

Results: The shortest distance from the medial epicondyle to the median nerve was 31.3±3.7 mm, and the distance in the fascia dissecting direction was 45.5±3.9 mm. The shortest distance from the coronoid process to the median nerve was 8.1±1.8 mm, and the dissection length of muscle and fascia was 47.0±8.7 mm. The width of the attachment point of the brachial muscle was 26.6±1.3 mm, the distance from the proximal and distal portions of the attachment point to the median nerve was 13.4±1.8 and 5.9±1.2 mm, respectively.

Summary Points: Hotchkiss’ over-the-top approach is useful because it exposes the coronoid process, but when inserting a screw from the coronoid process tip, the muscle and fascia must be dissected approximately 47 mm. Surgeons must be alert when placing a plate after dissecting the attachment point of the brachial muscle, as a more distal point results in a shorter distance to the median nerve.

References: Reference 1: Hotchkiss RN, Kasparyan NG. The medial “Over the top” approach to the elbow. Techniques in Orthopaedics. 2000: 15(2);105-112. Reference 2: O'Driscoll SW, Jupiter JB, Cohen MS, Ring D, McKee MD. Difficult elbow fractures: pearls and pitfalls. Instr Course Lect. 2003;52:113-34. Reference 3: Ring D, Doornberg JN. Fracture of the anteromedial facet of the coronoid process. Surgical technique. J Bone Joint Surg Am. 2007 Sep;89 Suppl 2 Pt.2:267-83. Reference 4: Doornberg JN, Ring DC. Fracture of the anteromedial facet of the coronoid process. J Bone Joint Surg Am. 2006 Oct;88(10):2216-24. Reference 5: Ring D. Fractures of the coronoid process of the ulna. J Hand Surg Am. 2006 Dec;31(10):1679-89. Reference 6: Hull JR, Owen JR, Fern SE, Wayne JS, Boardman ND 3rd. Role of the coronoid process in varus osteoarticular stability of the elbow. J Shoulder Elbow Surg. 2005 Jul- Aug;14(4):441-6. Reference 7: Cheung EV, Steinmann SP. Surgical approaches to the elbow. J Am Acad Orthop Surg. 2009 May;17(5):325-33. Reference 8: Reichel LM, Milam GS, Reitman CA Anterior approach for operative fixation of coronoid fractures in complex elbow instability. Tech Hand Up Extrem Surg. 2012 Jun;16(2):98- 104 Reference 9: Adams JE, Hoskin TL, Morrey BF, Steinmann SP. Management and outcome of 103 acute fractures of the coronoid process of the ulna. J Bone Joint Surg Br. 2009 May;91(5):632-5. Reference 10: Hull JR, Owen JR, Fern SE, Wayne JS, Boardman ND 3rd. Role of the coronoid process in varus osteoarticular stability of the elbow. J Shoulder Elbow Surg. 2005 Jul- Aug;14(4):441-6.

♦ No relevant financial relationships to disclose E-poster 48: The Vascularity of the Lunate: a Microtomodensitometry Study

Category: Anatomy Keyword: Hand and Wrist N/A - Not a clinical study

♦ Nick A.van Alphen, MD

Hypothesis: The primary scope of this study was to assess the intraosseous vascular anatomy of the lunate with high-resolution micro-CT and to potentially identify “safe-zones” for surgical interventions in the lunate. Our hypothesis is that the high incidence of traumatic and non-traumatic avascular necrosis of the lunate is due to poor vascular distribution of the intraosseous blood vessels.

Methods: Thirteen fresh cadaver wrists were obtained from the Department of Anatomy at Mayo Clinic, Rochester, MN. Both the ulna and radial artery were cannulated with a 20-gauge catheter. The pedicles were flushed with heparinized saline and formalin, and then injected with a lead-based contrast polymer (Microfil MV-117) under a physiologic pressure of 140 mmHg monitored by a pressure monitor. After 48 hours, the polymer was set. The lunate bone was transected and scanned at 20-µm/voxel resolution using a custom bench-top micro-CT scanner (1). The microcomputed tomography scanner generates three-dimensional images consisting of up to a billion cubic voxels, each 5–25 µm on a side. Tomographic reconstruction algorithms applied to these recorded images, were used to generate 3D images of the specimens.

Results: Thirteen lunate specimens were scanned and incorporated into a 3D rendering. Ten specimens had consistent nutrient vessels entering the bone from dorsal and volar; one specimen had no volar nutrient vessels; two specimens had no dorsal nutrient vessel. The branching pattern of the intraosseous blood vessels was consistent between all specimens. The connection between nutrient vessels could be classified as X-, Y- and I-shaped, as described by Gelberman et al (2). The distribution in this series was respectively 15%, 23% and 62%. The main connecting vessel was situated in the center or the distal half of the lunate. Two lunate specimens had a more ulnar-volar entering nutrient vessel, where one of the side-branches was supplying the entire radio-volar portion of the lunate.

Summary Points: - This study used a novel digital technique to assess the blood supply with high-resolution micro- CT. - A consistent connection between nutrient vessels entering from both dorsal and volar characterizes the vascular architecture. - Disruption of the main connecting vessel by surgical intervention or other mechanism would create one terminal nutrient vessel, thus creating a high risk of partial avascular necrosis. - Safe-zones for surgical interventions in the lunate bone were identified, which will help minimizing iatrogenic avascular necrosis of the lunate bone by respecting the intraosseous blood supply of the lunate bone, and changing our surgical approach accordingly.

References: Reference 1: Jorgensen SM, Demirkaya O, Ritman EL. Three-dimensional imaging of vasculature and parenchyma in intact rodent organs with X-ray micro-CT. The American journal of physiology. Sep 1998;275(3 Pt 2):H1103-1114. Reference 2: Gelberman RH, Bauman TD, Menon J, Akeson WH. The vascularity of the lunate bone and Kienbock's disease. The Journal of hand surgery. May 1980;5(3):272-278.

♦ No relevant financial relationships to disclose

E-poster 49: Relevance of Double Crush on Outcomes of Carpal and Cubital Tunnel Surgery

Category: Treatment, Prognosis/Outcomes, Patient Education Keyword: Hand and Wrist Level 3 Evidence

♦ Lauren E Wessel, BS ♦ Duretti T Fufa, MD ♦ Bruce Canham, MD ♦ Adam La Bore, MD ♦ Martin I Boyer, MD, FRCS(C ● Ryan Patrick Calfee, MD

Hypothesis: The association between cervical root and distal nerve compression has been well reported (1- 7). A proximal lesion may predispose the distal segment of the axon to damage through the disruption of axoplasmic flow (1). The purpose of this study was to determine the effectiveness of carpal and cubital tunnel surgery in patients with a history of cervical root decompression versus those without prior cervical spine decompression. We hypothesized that patients who have undergone cervical spine surgery would have an increased rate of persistent subjective symptoms and objective signs following carpal or cubital tunnel release based on the rationale that nerves subjected to double crush would have less recovery potential compared to nerves treated for isolated sites of compression.

Methods: This case control study compared 25 patients after carpal or cubital tunnel surgery following cervical spine surgery (double crush group) with 51 (1:2 ratio) controls matched by age, peripheral nerve procedure, and gender without history of cervical spine surgery (isolated peripheral nerve surgery group) (Table 1). Prior cervical spine procedures included anterior fusion/instrumentation, disc arthroplasty, laminectomy, foraminotomy, facetectomy, laminoplasty and posterior decompression. A minimum of 90 days follow-up was required following peripheral nerve decompression to assess residual symptoms and signs of nerve compression (median 752, range 92 to 3,685 days). Surgical outcomes were defined based on the presence or absence of improved subjective symptoms and improved two-point discrimination.

Results: Seventy eight percent of patients in the isolated peripheral nerve surgery group reported satisfactory improvement in pre-operative symptoms after peripheral nerve surgery compared to 44% of patients in the double crush group (P = 0.004). Complete resolution of subjective numbness and tingling was observed in 63% of the isolated peripheral nerve decompression group versus 24% of the double crush group (P= 0.003) (Table 2). Following peripheral nerve surgery, only 10% of patients in the isolated nerve compression group exhibiting elevated or unimproved two-point discrimination versus 33% of patients in the double crush group (P = 0.165) (Table 2).

Summary Points: 1. At a minimum of 90 days following carpal and cubital tunnel surgery, those patients with a history of prior cervical spine surgery are more likely to report persistent numbness and tingling and exhibit elevated two-point discrimination than patients with isolated peripheral nerve surgery. 2. Double crush syndrome may impact the ability of the median and ulnar nerve to recover after surgery for peripheral compression.

References: Reference 1: Upton RM, McComas AJ. The double crush in nerve entrapment syndromes. Lancet 1973;2:359-362. Reference 2: Wilbourne AJ, Gilliatt RW. Double crush syndrome: a critical analysis. Neurology 1997;49:21-29. Reference 3: Morgan G, Wilbourn AJ. Cervical radiculopathy and coexisting carpal tunnel syndrome: a double crush syndrome? Neurology 1998;50:78-83. Reference 4: Baba H, Maezawa Y, Uchida K, Furusawa N, Imura S, Kawahara N, Tomita K. Cervical myeloradiculopathy with entrapment neuropathy: a study based on the double-crush concept. Spinal Cord 1998;36:399-404. Reference 5: Choi S-J, Ahn, D-S. Correlation of Clinical History and Electrodiagnostic Abnormalities with Outcome after Surgery for Carpal Tunnel Syndrome. Plastic & Reconstructive Surgery 1998;102(7):2374-2380. Reference 6: Eason SY, Belsole RJ, Greene TL. Carpal Tunnel Release: Analysis of suboptimal results. J Hand Surgery 1985;10:365-369. Reference 7: Osterman AL.The double crush syndrome: cervical radiculopathy and carpal tunnel syndrome. Orthop Clin North Am 1988;19:147-155.

Table 1

Patient Demographics

Double Crush Group Isolated Peripheral Nerve Surgery Group Age (mean, years of age) 55.1 51.6 Procedure CTS 11/25 (44%) 24/51 (47%) CuTS 3/25 (12%) 5/51 (10%) CTS and CuTS 11/25 (44%) 22/51 (43%) Gender (% male) 8/25 (32%) 18/51 (35%) Table 2

Subjective and Objective Outcomes

Pre- and Post-operative Numbness and Tingling Pre- and Post-operative Two-Point Discrimination Percent of patients Percent of patients Percent of patients with Percent of reporting preoperative reporting postoperative elevated preoperative patients with numbness and tingling numbness and tingling two point discrimination elevated or non- improved two point discrimination Double Crush Group 88% (22/25) 76% (19/25) 59% (10/17) 33% (4/12) Isolated Peripheral 94% (48/51) 37% (19/51) 59% (17/29) 10% (3/29) Nerve Surgery Group *Analysis of pre-operative 2PD was included for all subjects with pre-operative measurements recorded. Analysis of post-operative 2PD was included for only those patients with both pre- and post-operative measurements recorded.

● Consulting Fee: DePuy/Synthes (Calfee) ● Contracted Research (Calfee)

♦ No relevant financial relationships to disclose

E-poster 50: Technical note about using temporary bridge plate for comminuted interphalangeal joint fracture

Category: Treatment Keyword: Hand and Wrist Level 4 Evidence

♦ Jinrok Oh, MD PhD

Hypothesis: Dynamic external fixation has been mainly used for treatment of comminuted interphalangeal joint fracture; however, maintaining the fixation through this method has been difficult and uncomfortable. Based on the principle of ligament taxis, we introduce a novel method of inserting pre-bent metal hand mini-plate through minimal invasive technique for fixation and bony reunion of fragments resulted by intra-articular comminuted fracture.

Methods: Fixation technique with pre-bent hand mini-plate was used in 7 cases of comminuted fracture of PIP and 1 case of first CMC joint fracture. Temporary fixation was applied for 6 weeks, followed by plate removal and brisement manipulation and then passive continuous ROM exercise. The cases were followed up for a mean duration of 17 weeks, and simple radiographs recorded the degree of bony reunion and the ROM of interphalangeal joints measured with protractor.

Results: An overall satisfactory result was achieved in all patients, with the mean ROM of 7 cases of PIP joint fracture being 2 degrees of extension and 95.5 degrees of flexion and that of 1 case of CMC fracture being 0 degrees of extension and 58.5 degrees of flexion. Furthermore, no serious complication was noted in any patient.

Conclusion: Bridge plating method using ligament taxis may be a viable method in treating comminuted interphalangeal joint fracture.

♦ No relevant financial relationships to disclose

E-poster 51: Radiographic and arthroscopic assessment of DRUJ instability due to foveal avulsion of the radioulnar ligament in distal radius fractures

Category: Evaluation/Diagnosis, Treatment Keyword: Hand and Wrist Level 3 Evidence

♦ Toshiyasu Nakamura, MD, PhD ♦ Noboru Matsumura, MD, PhD ♦ Takuji Iwamoto, MD, PhD ♦ Kazuki Sato, MD, PhD ♦ Yoshiaki Toyama, MD, PhD

Hypothesis: As the triangular fibrocartilage complex (TFCC) anchors the distal radius to the ulna via the radioulnar ligament (RUL), severely displaced distal fragment of the radius may be associated with a foveal avulsion of the TFCC. The purpose of this retrospective study was to radiographically and arthroscopically assess the relationship between the displacement of the radius, ulnar styloid and avulsion of the RUL resulting in DRUJ instability.

Methods: 29 wrists of 29 patients of intra- and extra-articular distal radius fractures/malunion who underwent reduction or a corrective osteotomy of the displaced/malunited fracture, and/or wrist arthroscopy were assessed radiographically and arthroscopically. Radial translation (Fig 1), radial inclination, radial shortening, volar or dorsal tilt and the presence of an ulnar styloid fracture with more than 4 mm of displacement were measured from the initial films. Radiocarpal arthroscopy was used to assess peripheral lesions of the TFCC, while DRUJ arthroscopy was used to assess the foveal attachment. The relationship between displacement of the distal radius or the ulnar styloid fracture and the TFCC injury including avulsion of the RUL (Fig 2) was recorded.

Results: Univariate analysis revealed that increased radial translation, decreased radial inclination, increased radial shortening and a radially displaced ulnar styloid fragment of more than 4 mm were significant predictors of RUL avulsion at the fovea. Volar or dorsal tilt of the radius and ulnar variance did not correlate with RUL avulsion or TFCC injuries. Multiple logistic regression analysis revealed that radial translation was an independent risk factor of foveal avulsion of the RUL.

Summary Points: Increased radial translation and radial shortening, decreased radial inclination of the distal fragment can be associated with a foveal avulsion of the RUL. Radial translation can be an independent risk factor of foveal avulsion of the RUL.

References: Reference 1: Nakamura T, Yabe Y, Horiuchi Y. Functional anatomy of the triangular fibrocartilage complex. J Hand Surg Br 1996; 21 (5) 581-586 Reference 2: Fujitani R, Omokawa S, Akahane M, Iida A, Ono H, Tanaka Y. Predictors of distal radioulnar joint instability in distal radius fractures. J Hand Surg Am 2011; 36 (12): 1919-1925 Reference 3: Nakamura T, Sato K, Okazaki M, Toyama Y, Ikegami H. Repair of foveal detachment of the triangular fibrocartilage complex: Open and arthroscopic transosseous techniques. Hand Clin 2011; 27 (3): 281-290

♦ No relevant financial relationships to disclose

E-poster 52: A Prospective Randomized Clinical Trial of Full-Time versus As-Desired Splint Wear for de Quervain Tendinopathy

Category: Treatment, Therapy/Rehabilitation, Prognosis/Outcomes, Patient Education Keyword: Hand and Wrist Level 2 Evidence

♦ Mariano E. Menendez, MD ♦ Emily Thornton, BSc ♦ David C. Ring, MD, PhD

Hypothesis: There is no consensus on the best protocol for splint wear in the non-operative management of de Quervain tendinopathy. We tested the primary null hypothesis that there is no difference in upper-extremity disability 8 weeks after initiating splinting between patients prescribed full-time or as-desired splint wear.

Methods: Eighty-three patients diagnosed with de Quervain tendinopathy were randomly allocated into two different splint-wearing instructions: full-time wear (N=43) or as-desired wear (N=40). At enrollment, patients had grip strength measured and completed measures of upper-extremity disability, pain intensity, and psychological distress. An average of 7.5 weeks later, patients returned for a second visit. Analysis was by intention-to-treat and with use of mean imputation for missing data.

Results: Fifty-eight patients (70%; 26 in the full-time cohort, and 32 in the as-desired cohort) completed the study. There were no statistically significant differences in disability, grip strength, pain intensity, and treatment satisfaction between patients instructed to wear the splint full-time and those instructed to use it as desired. Disability at final evaluation correlated significantly with baseline levels of pain anxiety, catastrophic thinking, and symptoms of depression, with the latter one accounting for 32% of the variation in the final multivariable model (p<0.001).

Summary Points: There is no difference in patient-reported outcomes and grip strength with full-time or as- desired splinting, and patients can wear the splint as they prefer.

♦ No relevant financial relationships to disclose E-poster 53: Distribution of Coronoid Fracture Lines by Specific Patterns of Traumatic Elbow Instability

Category: Evaluation/Diagnosis, Anatomy Keyword: Elbow and Forearm Level 4 Evidence

♦ Jos J.Mellema, MD ♦ Job N. Doornberg, MD PhD ● George S. M. Dyer, MD ♦ David C. Ring, MD, PhD

Hypothesis: By mapping fractures of the coronoid we can define the location and frequency of fracture lines of specific injury patterns of the coronoid. We tested the null hypothesis that specific coronoid fractures do not associate with specific overall traumatic elbow instability injury patterns and depicted this on fracture maps and heat maps.

Methods: We collected 110 CT’s from patients identified with coronoid fractures. Fracture types and pattern of injury were characterized based on anteroposterior and lateral radiographs, 2D and 3D CT scans, and intra-operative findings, as described in operative reports. Using quantitative 3D CT techniques we were able to reconstruct the coronoid and reduce fracture fragments. Based on these reconstructions fracture lines were identified and graphically superimposed onto a standard template in order to create 2D fracture maps. To further emphasize the fracture maps, the initial diagrams were converted into fracture heat maps following arbitrary units of measure. In statistical analysis Fisher’s exact test was used to evaluate the association between coronoid fracture types and elbow fracture-dislocation patterns.

Results: Forty-seven coronoid fractures were associated with a terrible triad fracture-dislocation, 30 with a varus posteromedial rotational injury, 1 with a anterior olecranon fracture-dislocation, 22 with a posterior olecranon fracture-dislocation, and 7 with a posterior Monteggia injury associated with terrible-triad fracture-dislocation of the elbow. The association between coronoid fracture types and elbow fracture-dislocation patterns, as shown on 2D fracture and heat maps, was strongly significant (Figure 1).

Summary: Our fracture maps and heat maps further support the observation that specific patterns of traumatic elbow instability have correspondingly specific coronoid fracture patterns. Knowledge of these patterns is useful for planning management, because it directs exposure, fixation, and associated ligament injuries and fractures that might benefit from treatment.

References:

● Other (Please describe): DePuy, Stryker, Synthes (Dyer)

♦ No relevant financial relationships to disclose

E-poster 54: Missing Data: A Major Limitation of Evidence Based Scientific Literature in the Journal of Hand Surgery

Category: Historical Information Keyword: General Principles N/A - Not a clinical study

♦ Abdo Bachoura, MD ♦ Alex Ferikes, MD ♦ Tiana Monostory, BS ♦ John Lubahn, MD

Hypothesis: Evidence based medicine is generally revered as an objective, peer-reviewed process that promotes improved medical practice. Raw clinical data is the basic foundation of all clinical studies . An examination of the completeness and quality of raw data however, appears to be absent from discussion. Clinical studies rarely mention the completeness of the data sets analyzed, yet missing data could be a significant source of bias and erroneous conclusions. In this study, we set out to analyze the frequency and nature of missing data discussion, as well as techniques employed by authors to deal with this aspect of clinical research.

Methods: All scientific studies published in the Journal of Hand Surgery (American Volume) between 2008 and August 2010, were reviewed. The type of study (therapeutic, prognostic, diagnostic), level of evidence (levels I-IV), and nature (retrospective or prospective) as well as the number of included and analyzed cases were collected. Studies that directly mentioned the presence of missing data or presented missing data for included patients were recorded, as were the various reconciliation strategies. Studies that excluded patients with missing data a priori, were not considered to have discussed missing data.

Results: After excluding case reports, anatomical, cadaveric, biomechanical, epidemiologic, economic and basic science studies, a total of 173 studies that included 9,513 cases were assessed. Sixteen studies (9%) directly or indirectly mentioned the presence of missing data. Further breakdown of these 16 studies revealed that 94% were therapeutic studies, 75% were retrospective in nature and 6%, 13%, 13% and 69% had a level of evidence of I, II, III and IV respectively. Strategies for dealing with missing data included case deletion (50%), simple imputation (6%), data- replacement (6%) and unclear strategies in 38% of studies.

Summary Points: • When considering scientific evidence-based literature in the Journal of Hand Surgery, missing data across all levels of evidence is an under-reported and under-appreciated limitation. • In order to improve the scientific rigor, objectivity and quality of the peer review process, it is suggested that authors and reviewers actively engage in the discussion of the completeness of the raw data, as this could impact study findings. • Legitimate statistical strategies that deal with missing data are currently available and could strengthen the quality of clinical research in this journal.

References: Reference 1: Sorensen AA, Wojahn RD, Manske MC, Calfee RP. Using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement to assess reporting of observational trials in hand surgery. J Hand Surg Am. 2013 Aug;38(8):1584-9.e2. doi: 10.1016/j.jhsa.2013.05.008. Reference 2: Bot AG, Ferree S, Neuhaus V, Ring D. Factors associated with incomplete DASH questionnaires. Hand (N Y). 2013 Mar;8(1):71-6. doi: 10.1007/s11552-012-9480-7.

♦ No relevant financial relationships to disclose

E-poster 55: a new nerve approximator

Category: Surgical Technique Keyword: Nerve Level 4 Evidence

♦ Jagannath Kamath, MS Ortho ♦ Nikil Jayasheelan, MS Ortho

Hypothesis: The role of nerve approximator in peripheral neurorrhaphycannot be over emphasized.Apart from the fine suture materials,instruments &magnification, thenerve approximator is the only device whichcan help the surgeon in optimizing the results of nerve repair.Commercially available nerve approximators are not readily available.Though these nerve approximators have served the purpose and stood the test of time,they have left a scope for further modification and simplification without compromising the basic purpose of nerve approximator.

Method: The newly described nerve approximatoris a device which can be prepared and customizedinstantaneously in any operation theatre,on the table using a piece of silicon rubber tubing and two hypodermic needles. A piece of sterile silicon rubber tube (e.g.Foley’s catheter) of 3 cms length is obtained with in internal diameter of 3mm.A small piece of k-wire with a diameter of 2.5 mm of length 3cms is inserted into the rubber tube to add stability for the frame.A hypodermic needle of appropriate size (23/25 gauge) is obtained to transfix the rubber tube at about 5mm from one end of the frame. This leaves a sufficient length of the needle which is long enough to transfix the one end of the cut nerve obtaining the purchase only through the meso and epineurium roughly about 1cm from the cut end of the otherwise prepared proximal end of the nerve.The same exercise is repeated using one more needle of same size across the rubber tube at about 5mm at the other end of the frame.The second needle will now be ready to transfix the distal segment of the cut nerve at about 1 cm from its tip.The free ends of the 2 needles can now be introduced into one more set of rubber tube. Now the anterior wall of the nerve is ready for repair.. Some fine tuning of tension can be achieved by either compressing or distracting the needles depending on the requirement.Once the anterior wall is repaired the whole apparatus can be flipped over to repair the posterior wall.

Results: We have been using this method of neurorrhaphy in the arm and forearm for 2 years and we have not encountered any drawbacks.

Summary points: It’s a simple surgeon friendly method of nerve approximator which can be easily prepared on the table.

♦ No relevant financial relationships to disclose

E-poster 56: The Effect of Dorsal Translation in Dorsally Angulated Distal Radius Fractures on Distal Radioulnar Joint Kinematics

Category: Basic Science Keyword: Hand and Wrist N/A - Not a clinical study

♦ Masao Nishiwaki, MD, PhD ♦ Mark Welsh, BScE ♦ Braden Gammon, MD, FRCSC ♦ Louis M Ferreira, PhD ♦ James A Johnson, PhD ♦ Graham JW King, MD, FRCSC

Hypothesis: Although dorsal translation deformities of the distal radius are often associated with dorsal angulation in patients with distal radial fractures and malunions, the magnitude of dorsal translation is rarely mentioned when evaluating fracture reduction and planning treatment. Our hypotheses were that increasing dorsal translation deformities would: (1) increase changes in the distal radioulnar joint (DRUJ) kinematics in the distal radius both with and without dorsal angulation, and (2) those changes would be greater following sectioning of the triangular fibrocartilage complex (TFCC).

Methods: Eight fresh-frozen cadaveric upper extremities were tested in a forearm motion simulator that produced active forearm rotation. Distal radial deformities of 0 mm, 5 mm, and 10 mm of dorsal translations with 0°, 10°, 20°, and 30° of dorsal angulations were simulated. Volar displacement of the ulna at the DRUJ as a result of each distal radial deformity was calculated during simulated active supination. Testing was peformed initially with the TFCC intact and repeated after sectioning of the TFCC at its ulnar insertion. Two-way or three-way repeated measures analyses of variance with Greenhouse-Geisser correction were used to analyze the effects of dorsal translation deformities on volar displacement of the ulna separately in TFCC intact and sectioned conditions.

Results: Increasing isolated dorsal translation deformities significantly increased volar displacement of the ulna at the DRUJ when the TFCC was intact (p < 0.001). In the intact TFCC, increasing dorsal translatioin combined with dorsal angulation also significantly increased volar displacement of the ulna compared with isolated dorsal angulation deformities (p < 0.001). Sectioning the TFCC further increased volar displacement of the ulna caused by each distal radial deformity (p = 0.001). Volar displacement of the ulna caused by combined deformities was larger in supination (p = 0.005).

Summary Points: • Dorsal translation deformities of the distal radius move the ulna volarly at the DRUJ in the distal radius both with and without dorsal angulation. • These results suggest the clinical importance of evaluating the magnitude of dorsal translation as well as the degree of dorsal angulation when managing displaced distal radius fractures and malunions. • The status of the TFCC should be evaluated carefully in addition to the magnitude of osseous deformity in patients with acute or healed displaced fractures of the distal radius, because changes in DRUJ kinematics caused by distal radial deformities are greater when the TFCC is ruptured.

References: Reference 1: Azzopardi T, Ehrendorfer S, Coulton T, Abela M. Unstable extra-articular fractures of the distal radius: a prospective, randomised study of immobilisation in a cast versus supplementary percutaneous pinning. J Bone Joint Surg Br. 2005; 87(6):837-840. Reference 2: Grewal R, MacDermid JC. The risk of adverse outcomes in extra-articular distal radius fractures is increased with malalignment in patients of all ages but mitigated in older patients. J Hand Surg Am. 2007; 32(7):962-970. Reference 3: Wong TC, Chiu Y, Tsang WL, Leung WY, Yam SK, Yeung SH. Casting versus percutaneous pinning for extra-articular fractures of the distal radius in an elderly Chinese population: a prospective randomised controlled trial. J Hand Surg Eur Vol. 201;35(3):202-208. Reference 4: Fraser GS, Ferreira LM, Johnson JA, King GJ. The effect of multiplanar distal radius fractures on forearm rotation: in vitro biomechanical study. J Hand Surg Am. 2009; 34(5):838- 848. Reference 5: Moore DC, Hogan KA, Crisco JJ, III, Akelman E, Dasilva MF, Weiss AP. Three- dimensional in vivo kinematics of the distal radioulnar joint in malunited distal radius fractures. J Hand Surg Am. 2002; 27(2):233-242. Reference 6: Crisco JJ, Moore DC, Marai GE, Laidlaw DH, Akelman E, Weiss AP et al. Effects of distal radius malunion on distal radioulnar joint mechanics--an in vivo study. J Orthop Res. 2007; 25(4):547-555. Reference 7: Miyake J, Murase T, Yamanaka Y, Moritomo H, Sugamoto K, Yoshikawa H. Three- dimensional deformity analysis of malunited distal radius fractures and their influence on wrist and forearm motion. J Hand Surg Eur. 2012; 37(6):506-512. Reference 8: Prommersberger KJ, Froehner SC, Schmitt RR, Lanz UB. Rotational deformity in malunited fractures of the distal radius. J Hand Surg Am. 2004; 29(1):110-115. Reference 9: Gordon KD, Dunning CE, Johnson JA, King GJ. Influence of the pronator quadratus and supinator muscle load on DRUJ stability. J Hand Surg Am. 2003; 28(6):943-950.

♦ No relevant financial relationships to disclose E-poster 57: Midterm Functional Outcomes of The Entire Upper Limb Replantation

Category: Treatment Keyword: Hand and Wrist Level 4 Evidence

♦ Tokio Kasai, MD

Hypothesis: The overall incidence of upper limb replantation is annually decreasing and, in particular, replantation proximal to the hand is becoming rare. Surgical techniques and postoperative care differ according to each level of upper limb amputation; however, the final clinical outcomes are not always favorable,and still not predictable. PURPOSE: We report the midterm clinical outcomes of the entire upper limb replantation and associated issues that we encountered.

Method: We evaluated a total of 55 patients (Male,53;Female, 2; mean age, 42 years; range, 2–79 years) who underwent upper limb replantation during a 10-year period (1999–2009) and whose follow- up was possible for 3 years (mean follow-up period, 5 years). Replantation proximal to the hand (proximal amputation) was performed in 10 patients (for the upper arm, 3; forearm, 2; and hand, 4). Finger replantation (distal amputation including zone V according to the Tamai classification) was performed in 45 patients. Fingertip replantations corresponding to zones I and II in the Tamai classification were performed in 23 patients.

Result: The overall survival rate was 85.5%. When examined according to the amputation site, the survival rate was 90% for proximal replantations, 84.4% for finger replantations, and 91.3% for fingertip replantations. The survival rates for zones III–V according to the Tamai classification were relatively poor compared with those for other zones in the finger. A postoperative functional evaluation of proximal replantation sites (Chen criteria) revealed that 66.7% were grade II (good) and 33.3% were grade III (fair). A postoperative functional evaluation of finger replantation (Tamai Evaluation Score) found that 70.3% were excellent, 21.6% were good, and 8.1% were fair. Functional outcomes were good for more distally located finger replantation compared with those for proximal replantation.

Summary points: 1) Postoperative outcomes of upper arm and proximal forearm replantations were influenced by the revascularization time, while taking into account the limit for warm ischemia time of the muscles. 2) Among proximal replantations, muscle transfers were performed in some patients to restore muscle power. 3) It was necessary to consider early mobilization of metacarpophalangeal and proximal interphalangeal joints while performing surgery to achieve good outcomes for finger replantation in zones III–V of the Tamai classification system. 4) For fingertip replantations, in addition to clinical outcomes, patient satisfaction was also high, leading us to conclude that a fingertip replant was effective.

References: Reference 1: Tamai,S. Twenty years experience of limb replantation: Review of 293 upper extremity replants. J.Hand Surg.Am 10:360,1985. Reference 2: Tsai,T.M.,McCabe,S.J., and Maki, Y. A Technique for replantation of the fingertip.Microsurgery 10:1,1989. Reference 3: Foucher,G and Norris R.W. Distal and very distal replanations. Br.J.Plast.Surg.45:199,1992 Reference 4: Goldner,R.D.,Urbaniak,J.R. Distal replantation at the level of the distal interphalangeal joint and the distal phalanx. J. Hand Surg. Am. 14:214,1989 Reference 5: Strauch,B Arterial system of the fingers. J. Hand Surg. Am.15:148,1990

♦ No relevant financial relationships to disclose

E-poster 58: Patients’ preferences for treatment for Dupuytren’s disease: Discrete Choice model

Category: Evaluation/Diagnosis, Surgical Technique, Prognosis/Outcomes, Patient Education Keyword: Diseases and Disorders Level 2 Evidence

♦ Hester Kan, MD ♦ Christianne van Nieuwenhoven, MD, PhD ♦ Ruud Selles, PhD ♦ Esther de Bekker-Grob, PhD ♦ Steven Hovius, MD, PhD

Hypothesis: Many treatment options are available for Dupuytren’s disease (DD) and these treatments differ significantly in attributes such as amount of contracture correction, complication rate, convalescence, and time to recurrence. The aim of this study is to determine patients’ preferences for different techniques of Dupuytren treatment and their attributes by using a discrete choice experiment.

Methods: We approached 973 patients who had sustained a variety of treatments for Dupuytren’s disease (collagenase injection, needle aponeurotomy, extensive percutaneous aponeurotomy and lipografting, limited fasciectomy and dermofasciectomy) between January 2009 and August 2012 to evaluate their choice of treatment. These patients were asked to fill in a questionnaire in which they had to repeatedly choose between three different hypothetical treatments. Each hypothetical treatment was characterized by various levels (values) of 7 different attributes: (1) treatment method, (2) major complications rate, (3) minor complications rate, (4) recovery period, (5) recurrence within 5 years, (6) extension deficit after treatment, and (7) aesthetic result. We analyzed the relative importance of these attributes and the trade-offs that patients were willing to make with a latent class model.

Results: 506 patients completed the extensive questionnaire. We found that the levels of all 7 treatment- attributes significantly contributed to the final treatment choice. Post treatment extension deficit and recurrence rate most significantly contributed to treatment choice, whereas aesthetic result and recovery time seemed less important. Patients were willing to trade an increase of 10.5% recurrent disease if they could receive needle aponeurotomy treatment instead of limited fasciectomy. Furthermore, patients accepted a 10% increment of recurrent disease for every 5% reduction of major complication. Patients also accepted 9 degrees increase of residual contracture after treatment, if there was at least 10% reduction of recurrence rate.

Summary: - In this discrete choice experiment, we showed that patients are willing to receive a treatment with a higher chance of recurrence of DD if the chance of major complications was reduced. - Patients considered a decrease of recurrent disease more important than reduction of convalescence. - This study provided more inside information concerning important factors for patients with DD. - This discrete choice experiment may improve treatment selection during patient-doctor interaction.

References: Reference 1: E.W. de Bekker-Grob et al.: Men's preferences for prostate cancer screening: a discrete choice experiment: BJC 2013 1-9

♦ No relevant financial relationships to disclose

E-poster 59: Radial Artery Pseudoaneurysm In Trapezio-Meta-Carpal Arthroscopy. A Case Report Review Of The Literature Regarding Complications And A Cadaveric Study

Category: Evaluation/Diagnosis, Treatment, Surgical Technique Keyword: Hand and Wrist Level 5 Evidence

♦ Philip Mathew, FRCS(ORTH) ♦ Tommy Lindau, MD, PhD

Hypothesis: Pseudoaneurysm of the radial artery is an unusual complication following arthroscopy of the trapezio-meta-carpal joint of the thumb

Methods: A 68 year old retired personal assistant presented with pain over the base of her right thumb. Clinical examination and radiography confirmed Eaton Grade I osteoarthritis of the trapezio- meta-carpal (TMC) joint of the thumb. She was initially treated with splinting and two steroid injections to the joint under fluoroscopic control. Due to lack of sustained relief she represented and was offered an arthroscopic evaluation of the TMC-joint. The 1U port was used as the initial viewing portal and the 1R as the initial working portal.In addition to partial synovectomy, two loose bodies were found and removed.Bare subchondral bone devoid of cartilage was seen on the base of the first metacarpal though the trapezial surface looked intact. At the two-week review, it was noted that there was a pulsatile swelling over the 1U portal. An ultrasound scan (USS) confirmed the clinical suspicion of a pseudo aneurysm and she underwent a successful coil embolisation of the radial artery just proximal to its termination by the interventional vascular radiologist. In order to further define a safe zone (with respect to the artery) for the ulnar portal, we dissected 5 fresh frozen cadaveric hands and exposed the radial artery alongside the clinically identifiable landmarks at the level of the TMC-joint and measured the distance form the edge of the tendons to the artery. The handling of human remains adhered to ethical and practical protocols. .

Results: At clinical review three months later it was felt that though the swelling had reduced, the thumb base was still painful. After due discussion the patient was offered and accepted the option of trapeziectomy and APL interposition arthroplasty procedure combined with exploration of the pseudoaneurysm. At the last follow-up, she is pain free and mobilising her thumb without discomfort. In all five specimens (table 1) the radial artery was consistently found to be at a distance of 10mm or more from the ulnar edge of the EPB-tendon. Summary Points: A thorough knowledge of the anatomy is essential to avoiding iatrogenic complications when embarking on arthroscopy in any joint of the body. Though rare, these complications are true learning points and should be reported to increase awareness among surgeons who perform these procedures be it routinely or occasionally.

References: Reference 1: Badia A. Arthroscopy of the trapeziometacarpal and metacarpophalangeal joints. The Journal of hand surgery. 2007;32(5):707-24. Epub 2007/05/08. Reference 2: Berger RA. A technique for arthroscopic evaluation of the first carpometacarpal joint. The Journal of hand surgery. 1997;22(6):1077-80. Epub 1998/02/21. Reference 3: Menon J. Arthroscopic management of trapeziometacarpal joint arthritis of the thumb. Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association. 1996;12(5):581-7. Epub 1996/10/01. Reference 4: Slutsky DJ. The use of a dorsal-distal portal in trapeziometacarpal arthroscopy. Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association. 2007;23(11):1244 e1-4. Epub 2007/11/08.

♦ No relevant financial relationships to disclose

E-poster 60: Dimensional Analysis of the Distal Phalanx with Consideration of Distal Interphalangeal Joint Arthrodesis using a Headless Compression Screw

Category: Treatment, Anatomy Keyword: Hand and Wrist, General Principles N/A - Not a clinical study

♦ Michael Darowish, MD ♦ Rodney Brenneman, MD ♦ Justin Bigger, MD

Hypothesis: The dimensions of many distal phalanges either preclude the use of certain implants or greatly increase the likelihood of complications with their usage.

Methods: Physical measurements of the distal phalanges were obtained from 5 cadaver hands and compared to their corresponding radiographic measurements to validate the accuracy of the measuring function of our institution’s imaging software. 200 de-identified hand radiographs were then selected. Inclusion criteria were patient age =18, atraumatic distal phalanges, and adequate visualization of each distal phalanx on posterior-anterior and lateral radiographs. Using our institution’s imaging software, the dorsal-volar (height) and radial-ulnar (width) dimensions of each distal phalanx at the thinnest portion just proximal to the tuft were measured and recorded. Two separate observers measured each digit three times. The mean measurement in each dimension for each digit was calculated. The intraclass correlation coefficient was calculated, showing excellent interobserver correlation of measurements. Subanalysis based on gender was performed.

Results 200 hand radiographs from 200 individuals were analyzed (age 18-97, mean 47). There were 117 females and 83 males, 106 right hands and 94 left hands. In all fingers, the dorsal-volar dimension of the distal phalanx was the smallest. The long finger was largest; small finger was smallest. Females were consistently smaller than males. (Table 1) The cutoff dimensions of 3.5mm, 3.1mm, and 2.8mm (the diameter of trailing threads of commonly used headless compression screws) were used to determine the percent of distal phalanges which could not accommodate each screw. (Table 2)

Summary Points Headless compression screws for distal interphalangeal (DIP) joint fusion provide compression and convenience to patient with no need for hardware removal. Fusion rates for DIP arthrodesis using headless compression screws are up to 100%. However, complication rates of DIP joint fusion have been reported from 0 – 22%, many related to screw cutout and resultant symptomatic hardware or nail problems. Based on our measurements, there are a significant number of distal phalanges that at their smallest dimension are too small to accommodate the most commonly used headless compression screws. Nearly 42% of small finger distal phalanges are too small to accommodate 2.8mm threads; that number increases to 95% with 3.2 mm diameter threads. Few to no distal phalanges, regardless of which finger, are large enough to accommodate 3.5mm diameter threads. Care must be taken in selecting appropriate implant for DIP fusion.

Table 1 – Measurement Mean by finger Finger Measurement Gender Dimension (mm) Overall 4.80 Width F 4.44 M 5.30 Index Overall 3.41 Height F 3.17 M 3.76 Overall 5.25 Width F 4.85 M 5.82 Long Overall 3.59 Height F 3.38 M 3.90 Overall 4.82 Width F 4.48 M 5.31 Ring Overall 3.32 Height F 3.12 M 3.61 Overall 3.69 Width F 3.39 M 4.13 Small Overall 2.88 Height F 2.68 M 3.17

Table 2 – Percent of digits with dimensions based on commonly used headless compression screws Percent of fingers Percent of fingers Percent of fingers <2.8mm <3.2mm <3.5mm Index 16 48 66 Overall Index 26 68 83 Female Long 4 24 51 Overall Long 6 39 72 Female Ring Overall 14 43 69 Ring Female 22 66 88 Small 42 81 97 Overall Small 65 95 100 Female

♦ No relevant financial relationships to disclose

E-poster 61: Rotational Anatomy of the Radius and Ulna: Surgical Implications

Category: Basic Science Keyword: Hand and Wrist, Elbow and Forearm N/A - Not a clinical study

♦ Parham Daneshvar, MD ♦ Ryan Willing, PhD ♦ Michael Lapner, MD, FRCSC ♦ Graham JW King, MD, FRCSC

Hypothesis: The purpose of this study is to provide the surgeon with some rotational landmarks for better understanding of the pathologies involving the radius and ulna. We hypothesize that the rotational anatomy of contralateral limbs are similar, and expect the location of the radial tuberosity to be opposite to the radial styloid.

Methods: Computed tomography images of 98 cadaveric forearms were obtained. These included 29 bilateral arms and 40 unilateral arms. Specimens with previous bony injuries were excluded. Using MIMICS (Materialise), three dimensional models of the entire radius and ulna were obtained and analysed using Paraview (Kitware). The rotation of the ulna was analysed by assessing the location of axis of the ulnar head and styloid with respect to the guiding ridge of the greater sigmoid notch. The rotation of the radius was assessed by comparing the twist of the volar cortex of the distal radius, midshaft interosseous ridge, and biceps tuberosity with respect to the distal radius joint axis.

Results: The ulnar styloid had a variable internal rotation of 8.4 ± 14.9° with respect to the guiding ridge of the greater sigmoid notch (Range 50.3°internal rotation to 22.0° external rotation). The side to side difference in orientation of the ulnar styloid in bilateral specimens is 8.2 ± 8.5° (p=0.31). The orientation of the volar cortex of the distal radius at the wrist joint line was 12.6 ± 5.4° in external rotation compared to the wrist joint axis. This external rotation of the volar cortex decreased more proximally with values of 12.6 ± 5.2°, 11.6 ± 4.7°, 8.9 ± 4.7 °, 6.7 ± 4.5°, 3.3 ± 5.1°, -0.1 ± 6.3°, & -13.1 ± 7.8° at 2, 4, 6, 8, 15, 30, and 60mm from the joint line. The axis of the mid biceps tuberosity was located at 43.8 ± 16.9° in external rotation from the axis of the wrist joint (Range 2.7° to 86.5°). The mean difference between contralateral biceps tuberosities was 7.0 ± 7.1° (p=0.09)

Summary Points: -The rotational anatomy of the radius and ulna varies significantly between individuals -There are similarities amongst contralateral radius and ulna rotational anatomy which can be of guidance when dealing with segmental bone loss, fracture malunion, and joint reconstruction. -The position of the biceps tuberosity is more anterior than previously thought -Understanding of rotational anatomy of the radius and ulna can play an important role in surgical planning

♦ No relevant financial relationships to disclose E-poster 62: A multicenter comparative study of two classification systems for radial polydactyly

Category: Evaluation/Diagnosis, Basic Science Keyword: Hand and Wrist, Congenital and Pediatric Problems N/A - Not a clinical study

♦ Christianne Avan Nieuwenhoven, MD, PhD ♦ Steven Hovius, MD, PhD

Hypothesis: In assessing the quality of results on treating radial polydactyly, patients should be evaluated according type of polydacytly. However, the mostly used Wassel classification does not seem to address to all radial polydactylies. To decide between this easy to use clinical classification and a more extensive classification, we compared occurrence of the different types and the reliability of the Wassel and Rotterdam classifications for radial polydactyly.

Methods: We classified a large population of radial polydactyly patients from two congenital hand specific clinics using both classification systems, and compared the incidences of the different types to a population derived from a systematic literature review. We further assessed intra- and interobserver reliability of both classification systems in a test-retest design with seven observers, using Kappa statistics.

Results: Forty percent of the 520 cases with available x-rays could not be classified using the Wassel classification, while all cases could be classified using the Rotterdam classification. All unclassifiable cases had aberrant components; the majority were of the triphalangeal (63%), deviating (43%) or hypoplastic (39%) kind. Types III, IV and VI occurred more often using the Rotterdam classification. Intra- and interobserver reliability was comparable for both classification systems (K = 0.87 vs. K = 0.83 and K = 0.65 vs. K = 0.70). Types II and IV had the lowest reliability in both the Wassel and Rotterdam classification (K ranging 0.30 – 0.59). Aberrant components indicating deviation and hypoplasia had the lowest reliability in the Rotterdam classification (K ranging 0.23 – 0.45).

Summary points: The Rotterdam classification has broader classification possibilities and similar intra- and interobserver reliability compared to the Wassel classification. Although it is more time- consuming and the aberrant components should be stricter defined to increase its clinical relevance, we recommend the Rotterdam classification for scientific use.

References: Reference 1: Clin Orthop Relat Res. 1969 May-Jun;64:175-93. The results of surgery for polydactyly of the thumb. A review. Wassel HD. Reference 2: J Hand Surg Am. 2008 Mar;33(3):373-7. doi: 10.1016/j.jhsa.2007.12.012. A classification system of radial polydactyly: inclusion of triphalangeal thumb and triplication. Zuidam JM, Selles RW, Ananta M, Runia J, Hovius SE.

♦ No relevant financial relationships to disclose

E-poster 63: The Use of an iPad to Evaluate Patient-Reported Functional Outcome Measures in a Hand Surgery Private Practice Setting

Category: Prognosis/Outcomes Keyword: Hand and Wrist, General Principles, Practice Management Level 2 Evidence

♦ Mark Ayaffe, MD ♦ Daniel Kokmeyer, MD ♦ Nitin Goyal, BA ♦ Gregory Merrell, MD

Hypothesis: Our hypothesis is that patients presenting with ailments of the hand and upper extremity will generally prefer an iPad-based system to traditional pen and paper, the use of the iPad will be associated with a significant increase in the completeness of data collection, and that significant time savings will be realized by clinicians through more efficient collection and recording of outcomes data.

Methods: 200 total patients were randomly divided into 4 equal cohorts. Group A and B (50 patients each) completed the Michigan Hand Questionnaire (MHQ) with pen and paper and iPad respectively, and Group C and D (50 patients each) completed the QuickDASH with pen and paper and iPad respectively. Identical questionnaires (MHQ or QuickDASH), verbal and written instructions were provided to each group. Basic demographic data including age, gender, and level of education were obtained. Questionnaires were analyzed to determine time for completion, number of question omissions, ease of survey completion, physical difficulty in survey completion, and patient preference for future questionnaire format.

Results: Use of the iPad was associated with a decrease in omitted questions (0.1 vs. 3.1) and an increase in scorable questionnaires (98% vs. 88%) relative to pen and paper. Time to questionnaire completion was greater with the use of the iPad relative to pen and paper for both the MHQ (8.6 vs. 7.6 minutes) and for the QuickDASH (4.4 vs. 1.5 minutes). 90% of those who were randomized to the iPad would prefer to use the iPad again in the future. When patients utilize an iPad instead of pen and paper, clinicians save up to 5 minutes per questionnaire by avoiding the need for manual data entry.

Summary Points: -Use of an iPad is a reasonable alternative to pen and paper to collect patient-reported outcome measures from patients with hand and upper extremity ailments in a private practice setting. -Use of an iPad reduces patient-reported questionnaire omissions and increases the number of "scorable" questionnaires. -Use of an iPad requires between 1-3 additional minutes for the patient to complete MHQ and QuickDASH questionnaires, but saves the clinician up to 5 minutes by making manual data entry unnecessary. -90% of patients who used the iPad would prefer to use the iPad again in the future.

♦ No relevant financial relationships to disclose E-poster 64: Migraine Headache as a Novel Risk Factor for Carpal Tunnel Syndrome – National Health Interview Survey, 2010

Category: Evaluation/Diagnosis Keyword: Hand and Wrist, Nerve, Diseases and Disorders Level 3 Evidence

♦ Huay-Zong Law, MD ♦ Bardia Amirlak, MD ♦ Jonathan J. Cheng, MD ♦ Douglas Sammer, MD

Hypothesis: Compression neuropathies have been associated with one another, and migraine headaches are being successfully treated by nerve decompression. The goal of this study is to evaluate whether an association exists between migraines and carpal tunnel syndrome (CTS), the most common compression neuropathy.

Methods: Data from the cross-sectional 2010 National Health Interview Survey Sample Adult module were used to calculate nationally-representative prevalence estimates and 95% confidence intervals of CTS and migraine headaches. The SAS 9.3 SURVEYFREQ function was used to account for the stratified sampling design, and chi-square analyses were used to determine statistically significant differences (p<0.05) among subgroups. The SURVEYLOGISTIC function was used to calculate adjusted odds ratios (aOR) and 95% confidence intervals (CI) for the degree of association between migraine headaches and CTS. This was performed using a multivariate logistic regression model controlling for known demographic and health-related factors, including age, gender, race/ethnicity, body mass index, diabetes status, and smoking status. Those included were adults at least 18 years old, those with complete data for all variables, and those of race/ethnicity groups large enough to be included in regression models.

Results: Of 27,157 respondents, 25,880 (95.3%) were included in the analysis. 952 (3.7%) of the respondents had CTS, and 4,212 (16.3%) had migraine headache. CTS was associated with older age, female gender, obesity, diabetes, and smoking. CTS was less common in Hispanics and Asians. Migraine headache was associated with younger age, female gender, obesity, diabetes, and current smoking. Migraine was less common in Asians. Migraine prevalence was 34% in those with CTS, compared to 16% in those without CTS (aOR 2.60, 95%CI 2.16-3.13). CTS prevalence in patients with migraine headache was 8%, compared to 3% in those without migraine headache (aOR 2.67, 95%CI 2.22-3.22).

Summary Points: This study is the first to demonstrate an association between CTS and migraine headache. Because migraine headache is more prevalent at younger ages, and CTS more prevalent at older ages, migraine headache may serve as a predictor of developing future CTS. Identification of those with migraine headache may allow for earlier diagnosis, treatment, or even prevention, of CTS. Longitudinal and genetic studies with physician verification of migraine headaches and CTS are needed to further define this association.

References: Reference 1: Tanaka S, Wild DK, Seligman PJ, Behrens V, Cameron L, Putz-Anderson V. The US prevalence of self-reported carpal tunnel syndrome: 1988 National Health Interview Survey data. American journal of public health. Nov 1994;84(11):1846-1848. Reference 2: Atroshi I, Gummesson C, Johnsson R, Ornstein E, Ranstam J, Rosen I. Prevalence of carpal tunnel syndrome in a general population. JAMA : the journal of the American Medical Association. Jul 14 1999;282(2):153-158. Reference 3: Geoghegan JM, Clark DI, Bainbridge LC, Smith C, Hubbard R. Risk factors in carpal tunnel syndrome. Journal of hand surgery. Aug 2004;29(4):315-320. Reference 4: Wise DM. Combined median and ulnar entrapment neuropathies. Plastic and reconstructive surgery. Jun 1999;103(7):2091-2092. Reference 5: Arnold WD, Elsheikh BH. Entrapment neuropathies. Neurologic clinics. May 2013;31(2):405-424. Reference 6: Smitherman TA, Burch R, Sheikh H, Loder E. The prevalence, impact, and treatment of migraine and severe headaches in the United States: a review of statistics from national surveillance studies. Headache. Mar 2013;53(3):427-436. Reference 7: Guyuron B, Kriegler JS, Davis J, Amini SB. Five-year outcome of surgical treatment of migraine headaches. Plastic and reconstructive surgery. Feb 2011;127(2):603-608. Reference 8: Blumenfeld A, Ashkenazi A, Napchan U, et al. Expert consensus recommendations for the performance of peripheral nerve blocks for headaches--a narrative review. Headache. Mar 2013;53(3):437-446. Reference 9: Aurora SK, Dodick DW, Turkel CC, et al. OnabotulinumtoxinA for treatment of chronic migraine: results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 1 trial. Cephalalgia : an international journal of headache. Jul 2010;30(7):793-803. Reference 10: National Center for Health Statistics. Data File Documentation, National Health Interview Survey, 2010 (machine readable data file and documentation). Hyattsville, Maryland: National Center for Health Statistics, Centers for Disease Control and Prevention; 2011.

♦ No relevant financial relationships to disclose E-poster 65: Isolated Volar Lunate Facet Fractures of the Distal Radius

Category: Evaluation/Diagnosis, Treatment, Surgical Technique, Prognosis/Outcomes, Anatomy Keyword: Hand and Wrist Level 4 Evidence

♦ Philipp Nicolas Streubel, MD ♦ Mark S. Cohen, MD

Hypothesis: Distal radius fractures with isolated involvement of the volar aspect of the lunate facet are rare. If inadequately treated, these may lead to radiocarpal joint subluxation and dysfunction of the distal radioulnar joint.

Methods: Eight patients who presented with an isolated volar lunate facet fracture were identified between 2008 and 2013. All underwent advanced imaging to define the injury followed by surgical intervention. Outcomes were assessed at a minimum 1-year follow-up, including range of motion, pain, DASH, PRWE scores, and radiographic studies.

Results: Patient ranged in age from 33 to 66 years. One patient underwent internal fixation through a standard FCR approach. At four weeks, loss of reduction was noted requiring revision surgery (Figure 1). In the remaining cases, a modified anterior approach between the flexor tendons and the ulnar neurovascular bundle was used. In these patients., uneventful healing was achieved. Fixation was performed with a 2.4mm buttress plate with our without a separate 2 mm lag screw (Figure 2). At final follow-up, all except the patient requiring revision surgery had a painless wrist. Total wrist motion measured 87% of the opposite side. Radiographic healing with anatomic wrist alignment was observed in all except the patient requiring revision. This patient had persistent joint subluxation with limitation of terminal supination. The remaining patients all achieved good or excellent functional outcomes.

Summary points: Isolated volar lunate facet fractures of the distal radius are exceedingly rare. Our experience suggests that optimal fracture exposure is not through a standard FCR approach but more ulnarly between the flexor tendons and ulnar neurovascular bundle. This allows for proper reduction and stabilization. Surgical strategies will be discussed. Legends: Figure 1. Left: Preoperative 3D CT scan reconstruction showing the morphology of an isolated volar lunate facet fracture. Right: Oblique radiograph at 4 weeks after fixation with a volar distal radius locking plate showing loss of reduction. Figure 2. Posteroanterior and lateral radiographs of a fracture treated primarily through a FCU approach with fixation using a 2 mm lag screw and a 2.4 mm reconstruction plate. Anatomic reduction and healing is seen at 1 year of follow-up.

References: Reference 1: Apergis E et al. Beware of the ulno-palmar distal radial fragment. J Hand Surg Br 2002;27B:139-145

Figure 1

Figure 2

♦ No relevant financial relationships to disclose

E-poster 66: Vibration Analgesia for Trigger Finger Corticosteroid Injections

Category: Treatment Keyword: Hand and Wrist, General Principles Level 1 Evidence

♦ Kevin W. Park, BA ♦ Martin I. Boyer, MD, FRCS(C ● Ryan Patrick Calfee, MD ♦ Charles A. Goldfarb, MD ● Daniel A Osei, MD

Hypothesis: Vibratory stimulation has been thought to decrease the pain experienced during injections of local anesthetics and botulinum toxin. We hypothesized that vibratory stimulation would decrease the pain experienced by patients during corticosteroid injections for trigger finger.

Methods: This randomized trial was powered (alpha = 0.05, beta = 0.80) to detect a 2-point change in VAS (20% effect size) with SD of 2.5 points. A total of 90 trigger finger injections were assigned to one of 3 cohorts. Patients received either no vibration (control group), "ultrasound vibration” (sham control group), or vibration (experimental group). A commercial hand-held massaging device (AcuVibe SoftTouch™, Long Beach, CA) was used to provide a 95Hz vibratory stimulus for the experimental group. The device was placed on the palm of the hand 2-3 cm from the site of injection and vibration was provided 3-5 seconds before the initial 30g needle stick and throughout the entire injection (standardized injection mixture consisting of 1mL methylprednisolone acetate, 0.5mL 0.5% bupivacaine, 0.5mL 1% lidocaine). In the sham control group, patients were informed that they would receive an "ultrasound" vibration that would be neither heard nor felt (the same device and protocol as that used in the experimental group was used with the exception that the device was not turned on and remained in the "OFF" position). In the control group, no device was used. VAS pain scores were obtained before and after the injection to assess the anticipated pain and the actual pain experienced. Analysis of variance (ANOVA) was used for the between-group comparison of parametric data and chi-square for categorical data.

Results: There were no differences between cohorts in terms of age, sex, location of injection, or whether a previous trigger finger injection was received or not. There were no significant between-group differences for anticipated pain or actual pain of injection (Figure 1). Actual pain was significantly higher than anticipated pain for patients who were receiving their first trigger finger injection (51.23 vs 31.85, p < 0.001) but not for patients who had received at least one previously (72.02 vs 63.58, p = 0.12; Figure 2).

Summary Points: • Vibratory stimulation does not reduce the reported pain of trigger finger injections. • Actual pain of trigger finger injections is higher than anticipated pain for patients receiving their first injection but not for patients who had received at least one previously, irrespective of the use of a concomitant vibratory stimulus.

References: Reference 1: Nanitsos E, Vartuli R, Forte A, Dennison PJ, Peck CC. The effect of vibration on pain during local anesthesia injections. Aust Dent J. 2009;54(2):94-100. Reference 2: Hutchins HS, Young FA, Lackland DT, Fischburne CP. The effectiveness of topical anesthesia and vibration in alleviating the pain of oral injections. Anesth Prog. 1997;44(3):87-89. Reference 3: Fayers T, Morris DS, Dolman PJ. Vibration-assisted anesthesia in eyelid surgery. Ophthalmology. 2010;117(7):1453-1457. Reference 4: Sharma P, Czyz C, Wulc AE. Investigating the efficacy of vibration anesthesia to reduce pain from cosmetic botulinum toxin injections. Aesthet Surg J. 2011;31(8):966-971. Reference 5: Goldfarb CA, Gelberman RH, McKeon K, Chia B, Boyer MI. Extra-articular steroid injection: early patient response and the incidence of flare reaction. J Hand Surg Am. 2007;32(10):1513-1520.

● Consulting Fee: DePuy/Synthes (Calfee, Osei) ● Contracted Research (Osei)

♦ No relevant financial relationships to disclose

E-poster 67: Closed radial wedge osteotomy for Preiser's disease.

Category: Treatment, Surgical Technique Keyword: Hand and Wrist Level 4 Evidence

♦ Yuji Tomori, MD ♦ Takuya Sawaizumi, MD ♦ Mitsuhiko Nanno, MD ♦ Shinro Takai, MD

Hypothesis: To elucidate the clinical outcome of five cases suffered from Preiser’s disease which treated with the closed radial wedge osteotomy (CRWO).

Methods: Five patients with Preiser’s disease that had all undergone the CRWO were investigated. The mean age at the time of surgery was fifty-nine years. On the basis of the Herbert&Lanzetta classification, two patients had stage-2, three patients had stage-3. Two patients had dorsal intercalated segmental instability (DISI) on the preoperative radiographic evaluation, and radiograph and CT imaging showed that two patients had stage-1 osteoarthritis of the radio- scaphid joint on the basis of Watson’s classification. According to the Kalainov classification on the MRI, three patients had type-1, two patients had type-2. One patient had simultaneously suffered from Kienböck disease, stage-1 on the Lichtman classification. The mean duration of follow-up was forty-eight months. Postoperative complications, the imaging evaluation of radiograph and MRI, clinical evaluation, including calculation of the modified Mayo wrist score, range of motion (ROM), and grip strength were all investigated. To evaluate DISI, scapho-lunate angle (SLA) was calculated on the radiograph.

Results: There were no complications such as infection, the neuropathy and non-union of distal radius. One patient had provisional pain on the dorsal radio-ulnar joint for one year, thereafter the pain disappeared. Although one patient claimed the residual pain, four patients had no pain at the final evaluation. Compared with the findings in the contralateral wrist, the mean ROM was 80% in flexion, 84% in extension, 95% in pronation, 100% in supination, and mean grip strength was 67%. The mean modified Mayo wrist score was 73 points and the clinical results were good in two, fair in two, and poor in one. Follow-up radiographs revealed that the Herebert&Latenza stage had progressed to stage-4 in all patients.

Summary point: Although the follow-up radiographs revealed that the Herebert & Latenza stage had progressed in all patients, mitigation of the wrist pain, patient satisfaction, and retention of ROM were satisfactory following the CRWO. This procedure is reliable treatment for Preiser’s disease, and may be a good option for patients with Herebert&Latenza stage 3 and 4. Type of study/Level of evidence: Therapeutic, Level 4.

References: Reference 1: Preiser G. Zur eine typische posttraumatische und zur Spontanfractur fuhrende Ostitis des Navicularecarpi. Fortschr Geb Roentgenstrahlen 15:189-197, 1910 Reference 2: Hayashi O, Sawaizumi T, Ito H. Closed radial wedge osteotomy for Preiser's disease: a report of four cases. Hand Surg 16:347-352,2011 Reference 3: Herbert TJ, Lanzetta M. Idiopathic avascular necrosis of the scaphoid. J Hand Surg 19-B:174-182,1994 Reference 4: Watson HK, Ballet FL. The SLAC wrist: scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg 9-A: 358-365,1984. Reference 5: Kalainov DM, Cohen MS, Hendrix RW, et al. Preiser's disease: identification of two patterns. J Hand Surg 28-A:767-778,2003 Reference 6: Lichtman DM, Mack GR, MacDonald RI,et al. Kienb?ck's disease: the role of silicone replacement arthroplasty. J Bone Joint Surg 59-A:899-908,1977 Reference 7: Kojima T, Kido M, et al. Wedge osteotomy of radius for Kienbock's disease. J Jpn Soc Surg Hand 1:431-434,1984 Reference 8: Lenoir H, Coulet B, Lazerges C, et al. Idiopathic avascular necrosis of the scaphoid: 10 new cases and a review of the literature. Indications for Preiser's disease. Orthop Traumatol Surg Res 98:390-397,2012 Reference 9: Moran SL, Cooney WP, Shin AY. The use of vascularized grafts from the distal radius for the treatment of Preiser's disease. J Hand Surg 31-A: 705-710,2006 Reference 10: De Smet L, Aerts P, Walraevens M, Fabry G. Avascular necrosis of the carpal scaphoid: Preiser's disease: report of 6 cases and review of the literature. Acta Orthop Belg 59:139-142,1993

♦ No relevant financial relationships to disclose

E-poster 68: Acute Metacarpophalangeal Joint Arthroplasty in the Setting of Trauma

Category: Evaluation/Diagnosis, Treatment, Prognosis/Outcomes Keyword: Hand and Wrist, General Principles Level 4 Evidence

♦ Matthew T. Houdek, MD ♦ Eric R. Wagner, MD ● Marco Rizzo, MD ♦ Robert E. Van Demark, III., MD ● Steven L. Moran, MD

Hypothesis: Although metacarpophalangeal (MCP) joint arthroplasty has emerged as a viable treatment for post-traumatic degenerative joint disease, MCP arthroplasty performed in the acute setting is uncommon. We report on the outcomes of 11 arthroplasties in 8 patients performed for trauma within 3 months of the initial injury.

Methods: We performed a review of all patients who underwent metacarpophalangeal (MCP) joint arthroplasty acutely for a traumatic injury performed at a single institution. Out of 820 MCP arthroplasties performed, 11 arthroplasties in 8 patients were performed in a traumatic setting within 3 months of the initial injury. On average the clinical follow-up was 2.4 years (range 0.5-6 years). Nine (82%) injuries were the result of a direct laceration from a sharp object over the MCP joint where the arthroplasty was performed within 24-hours of injury; while the other 2 patients underwent arthroplasty after a recurrent instability secondary to fracture comminution or soft tissue insufficiency and chondral injury. Ten (91%) patients received a pyrocarbon implant, with 2 (18%) procedures augmented with local autologous bone graft.

Results: Patients experienced excellent pain relief, with 7 out of 8 patients reporting none or mild pain at last follow-up. Postoperative grip strength, oppositional and appositional pinch strength were 28 kg (60%), 7.7 kg (90%) and 9.6 kg (50%), respectively. MCP, PIP and DIP extension to flexion arc averaged 10.2 – 65.0 degrees, 10 – 87.5 degrees, and 7.5 – 63.3 degrees, respectively. Five joints (45%) were not able to obtain full extension as last follow-up, while 2 (18%) had flexion contractures of at least 30 degrees. These same 2 joints with flexion contractures in 1 patient was the only patient who reported limitations in activities of daily living. Additional complications included 2 intraoperative fractures and 1 PE. Although there were no revision surgeries, 1 patient had an extensor tendon rupture at 18-months postoperatively, while another 3 joints manipulation and tenolysis for contractures within a year of the initial procedure. No demographic factors, comorbidities, or operative factors had any significant impact on the post- operative motion, limitations, or reoperations.

Summary Points: Metacarpophalangeal arthroplasty improves patient’s pain in the acute setting of a traumatic laceration or dislocation. However, some patients experience limitations in their total arc of motion, most likely as a result of the soft tissue injury associated with the initial injury. MCP arthroplasty should be a consideration in the acute setting for trauma in an effort to preserve the finger’s arc of motion.

References:

● Other (Please describe): TriMed; SBi; Elsevier (Rizzo)

♦ No relevant financial relationships to disclose

E-poster 69: The Effect of MCP Hyperextension on Outcomes in the Surgical Treatment of CMC Arthritis

Category: Treatment Keyword: Hand and Wrist Level 2 Evidence

♦ David M Brogan, MD ♦ Rose van Hogezand, . ♦ Nikola Babovic, BA ♦ Brian T Carlsen, MD ● Sanjeev Kakar, MD, MBA

Hypothesis: In the surgical treatment of thumb carpometacarpal (CMC) joint arthritis, patients without pre- operative metacarpophalangeal (MCP) hyperextension have improved functional outcomes compared to those with MCP deformity.

Methods: A retrospective review was conducted analyzing the functional outcomes of patients treated for CMC arthritis and MCP hyperextension between 1999-2009. All patients underwent surgical treatment of CMC joint arthritis by a fellowship trained hand surgeon with pre-operative and post-operative functional outcome data recorded. Standardized pre and postoperative assessments included pinch & grip strength, degree of MCP hyperextension and thumb radial and palmar abduction. Statistical analyses used included Kruskal-Wallis and t-test.

Results: A total of 225 patients met the inclusion criteria and outcome measures were reported at an average follow-up of 27.2 months. Patients were divided into three groups: 1) Patients without pre-operative MCP hyperextension (167 pts); 2) Patients with pre-operative MCP hyperextension but no treatment of the MCP (37 pts) and 3) Patients with pre-operative MCP hyperextension who had a concomitant procedure to address the MCP hyperextension (20 pts). All patients underwent either a Weilby (125 pts) or a ligament reconstruction tendon interposition (LRTI) (99 pts) to address CMC arthritis. The difference from pre to last post-op assessment was calculated and defined for each parameter as the delta. Analysis of the pre-operative outcomes data showed no difference in the baseline parameters among all three groups, with the exception of MCP hyperextension. The average pre-operative hyperextension deformity in group 2 was 14 degrees, while Group 3 had a statistically significant higher pre-operative hyperextension of 33 degrees (p < .0001). Average improvement for each parameter is listed in Table 2. There was no significant difference in delta for each of the outcomes between the three groups (Table 1). There was no statistically significant difference in improvement when comparing patients without MCP hyperextension to patients with MCP hyperextension, regardless of whether the MCP was addressed (Group 1 vs Group 2&3 combined).

Summary Points: There was no difference in functional outcome after treatment of CMC arthritis when comparing patients without pre-operative MCP hyperextension to those with hyperextension, regardless of whether or not the MCP was also addressed.

Table 1 N (# of Comparing Comparing Comparing patients Baseline Pre- Delta across Delta w/ data Op all 3 groups between available) Parameters Group 1 vs Among all 3 2&3 groups Palmar 64 P= 0.30 P=0.69 P = 0.50 Abduction Radial 72 P=0.72 P= 0.70 P = 0.40 Abduction Pinch Opp 112 P=0.76 P = 0.95 P = 0.74 Pinch App 188 P= 0.13 P = 0.24 P = 0.18 Grip 197 P =0.30 P = 0.34 P = 0.17

Table 2 Group 1 Group 2 Group 3 Palmar 5.2 6.4 12.6 Abduction (deg) Radial 5.1 7.8 11.5 Abduction (deg) Pinch Opp 0.3 0.2 0.3 (kg) Pinch App 0.6 -0.7 0.1 (kg) Grip (kg) 2.0 0 0.6 Group 1 = No pre-op MCP hyperextension Group 2 = Pre-op MCP hyperextension Group 3 = Pre-op MCP hyperextension + MCP Procedure

● Consulting Fee: Arthrex Inc, Skeletal Dynamics(Kakar)

♦ No relevant financial relationships to disclose

E-poster 70: PIP extensor reconstruction by two-staged tendon transfer for the treatment of posttraumatic flexion deformity of the finger.

Category: Surgical Technique Keyword: Hand and Wrist Level 4 Evidence

♦ Kozo Shimada, MD, PhD ♦ Hidehiko Kawabata, MD ♦ Hiroyuki Tanaka, MD, PhD ♦ Ko Temporin, MD, PhD ♦ Akiko Tominaga, MD, PhD ♦ Ryosuke Noguchi, MD

Hypothesis: We introduced new treatment method for flexion deformity of the finger PIP joint. This method consists of three steps; 1) Physiotherapy for the PIP joint. 2) Silicon spacer placement through the route of lumbricalis. 3) Palmaris longus tendon graft through the tunnel transferring to EIP proximally. We clarify the clinical usefulness of the procedure.

Methods: Thirteen cases of posttraumatic flexion deformity of the finger PIP joint were treated. The age at surgery ranged from 10 to 65 years with mean of 48 years. Six cases were male and seven were female. All patients were suffering from posttraumatic flexion deformity of the finger. Preoperative finger flexion was 60 to 110 with mean of 87 degrees, and extension loss was 45 to 75 with mean of 61 degrees. They were instructed to stretch their finger by physiotherapists and applied extension splint before surgery. At the first operation, a silicon spacer was placed from the dorsal part of the PIP joint through subcutaneous tunnel created under the transverse metacarpal ligament up to the dorsal wrist nearby the EIP tendon. Three to six months after the first operation, the silicon spacer was replaced by PL tendon graft transferring to EIP. After three weeks immobilization, motion exercise was started.

Results: One patient encountered perioperative wound infection resulting in recurrence of contracture. Other twelve cases gained better active finger extension. Postoperative finger flexion was 50 to 100 with mean of 77 degrees, and extension loss was 0 to 30 with mean of 15 degrees. Average improvement of motion arc was 36 degrees. In four cases who obtained passively soft joint (passive full range of motion) by first step physiotherapy, they got almost full active range of motion after the procedure (90 degrees flexion with 8 degrees extension loss). In eight cases with still stiff joint after the first step physiotherapy, they obtained more 25 degrees arc (86 degrees flexion with 60 degrees extension loss preoperatively, and 70 degrees flexion with 19 degrees extension loss). They were satisfied with 41 degrees improvement of extension in spite of 16 degrees deterioration of flexion.

Summary Points: Reconstruction of finger extensor mechanism was difficult because of possible postoperative adhesion and difficulties of power balance. Our procedure of two-staged PIP extensor reconstruction for flexion contracture of the finger was useful. Preoperative physiotherapy and close attention to the fragile surgical wound was important to obtain better function.

♦ No relevant financial relationships to disclose E-poster 71: Comparison of Cortisone Injection and Percutaneous Trigger Finger Release For 308 Trigger Thumbs

Category: Treatment, Prognosis/Outcomes Keyword: Hand and Wrist Level 3 Evidence

♦ Melissa Arief, MD ♦ Mukund R. Patel, MD ♦ Christian J. Zaino, MD

Hypothesis: This study sought to compare the success rate of cortisone steroid injection to that of percutaneous trigger finger release in patients presenting with trigger thumbs.

Methods: Outcomes via retrospective review were evaluated over a 5-year period from 2008-2013. We looked at patients who were either treated with local corticosteroid injection (N=150) or percutaneous trigger release under local anesthesia in the office with a sterile 18-gauge needle (N=158). Patients were followed for at least year. Patient demographics included pain, trigger finger grade, and duration of symptoms. Patients were assessed at follow up for pain, continued triggering, need for therapy after treatment, complications, and overall satisfaction. Exclusion criteria was strictly defined and included patients that were locked in flexion or extension.

Results: One hundred and fifty nine patients treated with corticosteroid injection were followed for one year and had an overall success rate based on outcome of 76%. In this group 12.6% required a second injection, 1.3% a third injection, 11.3% underwent a percutaneous trigger finger release, and 1.3% of patients received an open release. In the percutaneous release group 158 patients were followed for one year. There was an overall success rate of 98% with one patient that received a second percutaneous release. In both groups there were no complications, the therapy rate for the injection was 10% and 25% in the percutaneous group.

Summary: • The results of this study demonstrate a greater rate of success of percutaneous trigger finger release for trigger thumbs compared to the standard corticosteroid injection. • This study demonstrated no complications for a large series of patients demonstrating the safety of the percutaneous release in the office setting for the thumb, which remains a controversial topic given the proximity of the neurovascular structures.

References: Reference 1: Bamroongshawgasame T: A comparison of open and percutaneous pulley release in trigger digits, J.Med.Assoc.Thai. 93:199-204, 2010. Reference 2: Calleja H, Tanchuling A, Alagar D, et al.: Anatomic outcome of percutaneous release among patients with trigger finger, J Hand Surg Am 35:1671-1674, 2010. Reference 3: Fowler JR, Baratz ME: Percutaneous Trigger Finger Release, J Hand Surg Am 2013. Reference 4: 6. Frank SG, Lalonde DH: How acidic is the lidocaine we are injecting, and how much bicarbonate should we add?, Can J Plast Surg 20:71-73, 2012. Reference 5: Patel MR, Moradia VJ: Percutaneous release of trigger digit with and without cortisone injection, J Hand Surg [Am] 22:150-155, 1997. Reference 6: Pope DF, Wolfe SW: Safety and efficacy of percutaneous trigger finger release, J Hand Surg Am 20:280-283, 1995. Reference 7: Sato ES, Gomes Dos Santos JB, Belloti JC, et al.: Treatment of trigger finger: randomized clinical trial comparing the methods of corticosteroid injection, percutaneous release and open surgery, Rheumatology (Oxford) 51:93-99, 2012.

♦ No relevant financial relationships to disclose

E-poster 72: Prefixed and postfixed brachial plexus: is it clinically relevant?

Category: Anatomy Keyword: Shoulder and Arm, Nerve N/A - Not a clinical study

♦ Thomas J Kim, MD ♦ Brandon S Schwartz, MPH ● Joshua Abzug, MD

Hypothesis: A prefixed brachial plexus has been described as having a contribution to the plexus from C4 without a significant contribution from T1, while a postfixed brachial plexus has been described as having a T2 contribution without a significant contribution from C5. The reported incidence of a prefixed plexus ranges from 25% to 48%, whereas the incidence of a postfixed plexus has been reported to be 2% to 5%.(1,2,3) The purpose of this study was to assess the contributions from C4 and T2 and when present, to determine its clinical relevance.

Methods: The 66 brachial plexus’ (33 cadavers) were carefully dissected down to the root level in order to determine the presence of a C4 or T2 contribution. If a contribution was present, the significance of the contribution was assessed for clinical relevance. Sex, age and ethnicity of the cadavers were all also recorded to document any variation.

Results: 11 of 66 plexuses (20%) were found to have a prefixed brachial plexus with a contribution from the C4 nerve root. 80% of subjects with prefixed plexuses were female, and all were white. The majority (60%) of prefixed plexuses occurred on the right side, and a single cadaver exhibited bilateral contributions from C4. 9 of 66 plexuses (14%) were postfixed and found to have a contribution from the T2 nerve root. 75% of subjects with a postfixed plexus were female, and 75% were white. 4 of 8 (50%) subjects with a postfixed plexus exhibited a left-sided variant, while a single cadaver exhibited bilateral T2 contribution. The majority of C4 and T2 contributions that were found were single fascicle neural connections. 11 of 11 prefixed plexuses (100%) had single fascicle C4 contributions, and 7 of 9 postfixed plexuses (78%) had single fascicle T2 contributions. The total C2 or T4 contributions that were single fascicle connections was 18 of 20 (90%).

Summary Points: -A significant amount of variation in brachial plexus anatomy exists. -The percentage of plexus’ described previously as prefixed may be overestimated, whereas the percentage of postfixed plexus’ may be underestimated. 4,5,7 -Despite the presence of a pre- or postfixed plexus, the size of the C4 or T2 contribution may be of such diminutive diameter that the clinical relevance is questionable.

References: Reference 1: Matejcik V. Variations of nerve roots of the brachial plexus. Bratisl Lek Listy. 2005;106:34-36. Reference 2: Tubbs RS, El-Zammar D, Loukas M, Cömert A, Cohen-Gadol AA. Intradural cervical root adjacent interconnections in the normal, prefixed, and postfixed brachial plexus. J Neurosurg Spine. 2009;11:413-416. Reference 3: Uysal II, Seker M, Karabulut AK, Büyükmumcu M, Ziylan T. Brachial plexus variations in human fetuses. Neurosurgery. 2003;53:676-684. Reference 4: Pellerin M, Kimball Z, Tubbs RS, Nguyen S, Matusz P, Cohen-Gadol AA, Loukas M. The prefixed and postfixed brachial plexus: a review with surgical implications. Surg Radiol Anat 2010;32:251-260. Reference 5: Natsis K, Totlis T, Tsikaras P, Anastasopoulos N, Skandalakis P, Koebke J. Variations of the course of the upper trunk of the brachial plexus and their clinical significance for the thoracic outlet syndrome: a study on 93 cadavers. Am Surg. 2006 Feb;72(2):188-92. Reference 6: Lee HY, Chung IH, Sir WS, Kang HS, Lee HS, Ko JS, Lee MS, Park SS. Variations of the ventral rami of the brachial plexus. J Korean Med Sci. 1992 Mar;7(1):19-24 Reference 7: Monreal R. Restoration of elbow flexion by transfer of the phrenic nerve to musculocutaneous nerve after brachial plexus injuries. Hand (N Y). 2007 Dec;2(4):206-11.

● Royalty: Springer (Abzug) ● Consulting Fee: Axogen (Abzug)

♦ No relevant financial relationships to disclose

E-poster 73: Skin Surface Pressure under Short Arm Casts with an Evaluation of Three Cast-Cutting Methods for Pressure Reduction.

Category: Treatment, Anatomy, Basic Science, Medical/Legal Keyword: Hand and Wrist, General Principles N/A - Not a clinical study

♦ Christian J Zaino, MD ♦ Melissa Arief, MD ♦ Mukund R Patel, MD

Hypothesis: Limited data exist regarding edema-induced pressure within a short arm cast (SAC) in patients with distal radius fractures as well as pressure reduction due to cast cutting, the standard of care implemented to potentially reduce dangerous pressures to physiologic safe levels [1-5]. We sought to quantify both in an experimental model.

Methods: We measured skin surface pressures (SSPs) under SACs on 90 wrists from 45 healthy volunteers (average age: 39 years, age range: 19-87years) randomly assigned to one cast-cutting method: “single-cut” (cast bivalve, ace wrap), “double-cut” (cast bivalve, spread, ace wrap) or “triple-cut” (cast bivalve, spread, webril cut, ace wrap). The lead author casted each wrist in the neutral position with one roll of 2-inch cotton webril and one roll of 2-inch fiberglass, applied with the stretch-relax technique. Ace wrap was applied with 50% overlap and light stretching. Each SAC contained an empty saline bag used to simulate edema and facilitate measurement of SSP via the Ad-Instruments physiologic pressure transducer and monitor. We recorded SSPs with either 10 or 50cc of air infused into the saline bag. Student’s t-test was used with significance present when p<0.05.

Results: Each cast-cutting method significantly reduced the SSP from the average maximum of 92.49mmHg with 50cc of infused air (Figure 1). Specifically there was a 70.79% reduction (p<0.0001) in SSP for the single-cut method, an 85.1% reduction (p<0.0001) for the double-cut method, and a 99.93% reduction (p<0.0001) for the triple-cut method. Ace wrapping significantly increased final SSPs to a level of 40.81mmHg (p<0.0001) for single-cut, 32.98mmHg (p<0.0001) for double-cut, and 21.10mmHg (p<0.0001) for triple-cut SACs. Throughout this study women had higher SSPs than men (Figure 2); specifically, an average maximum 104.40mmHg vs. 81.10mmHg at 50cc of infused air (p<0.0001).

Summary Points: • Average maximum SSP of 92.49mmHg is dangerous and warrants cast cutting as this pressure is greater than that needed to occlude arteriolar capillaries of the fingers (30-60mmHg [4,5]) and skin microcirculation causing skin necrosis (60-75mmHg [2,3]); it is beyond the pressure which necessitates fasciotomy in patients with compartment syndrome [6-7]. • Only the triple-cut method reduced SSPs into the physiologic safe zone. • Ace wrapping a SAC increased SSPs by between 15-20mmHg, thus it is safest to apply an ace bandage with less stretching. • Finally, consistently elevated pressures in women correlate with the association between women who suffer distal radius fractures and the development of complex regional pain syndrome [1,4,8,9].

References: Reference 1: Field J. Complex regional pain syndrome: a review. The Journal of hand surgery, European volume. Jul 2013;38(6):616-626. Reference 2: Mohler LR, Pedowitz RA, Byrne TP, Gershuni DH. Pressure generation beneath a new thermoplastic cast. Clinical orthopaedics and related research. Jan 1996(322):262-267. Reference 3: Moir JS, Wytch R, Ashcroft GP, Neil G, Ross N, Wardlaw D. Intracast pressure measurements in Colles' fractures. Injury. Nov 1991;22(6):446-450. Reference 4: Patrick JH, Levack B. A study of pressures beneath forearm plasters. Injury. Jul 1981;13(1):37-41. Reference 5: Wytch PA, P; Kalisse, C.G.E. ; Neil, G; Ross, N; Ward, D. Interface pressures in below elbow casts. Clinical Biomechanics. 1991;6(1):25-30. Reference 6: Duckworth AD, Mitchell SE, Molyneux SG, White TO, Court-Brown CM, McQueen MM. Acute compartment syndrome of the forearm. The Journal of bone and joint surgery. American volume. May 16 2012;94(10):e63. Reference 7: Prasarn ML, Ouellette EA. Acute compartment syndrome of the upper extremity. The Journal of the American Academy of Orthopaedic Surgeons. Jan 2011;19(1):49-58. Reference 8: Field J, Protheroe DL, Atkins RM. Algodystrophy after Colles fractures is associated with secondary tightness of casts. The Journal of bone and joint surgery. British volume. Nov 1994;76(6):901-905. Reference 9: Raja SN, Grabow TS. Complex regional pain syndrome I (reflex sympathetic dystrophy). Anesthesiology. May 2002;96(5):1254-1260.

♦ No relevant financial relationships to disclose E-poster 74: Clinical Outcomes of Limited-Open Retrograde Intramedullary Headless Screw Fixation of Metacarpal Fractures

Category: Treatment, Surgical Technique Keyword: Hand and Wrist Level 4 Evidence

♦ David E.Ruchelsman, MD ♦ Sameer Puri, MD ♦ Natanya Feinberg-Zadek, PA ♦ Matthew Leibman, MD ♦ Mark R. Belsky, MD

Hypothesis: Fixation countersunk beneath the articular surface is well-accepted for peri-articular fractures. Quantitative 3D-CT data supports the use of an articular starting point for extra-articular metacarpal fractures[1]. Intramedullary headless compression screw (IMHS) fixation offers clinical advantages over percutaneous Kirschner wire and open techniques.

Methods: Retrospective review of prospectively collected data on a consecutive series of 3 8(33M; 5F) patients, mean age 28(range, 16-66) treated with IMHS fixation for displaced metacarpal neck/subcapital (n=25) and shaft (n=13) fractures at a single academic hand surgical practice between 2010-2013. This technique was also used for 5 nascent malunions (neck, n=2; shaft, n=3). The dominant hand was involved in 35/38 cases (92%). Mean preoperative magnitude of MC neck angulation was 53 degrees (range, 0-70), and shaft angulation was 35 degrees (range, 0-55). All patients began active motion within the first postoperative week. A hand based splint was utilized until suture removal. Clinical outcomes were assessed with digital goniometry, pad- to-distal palmar crease distance, and grip strength. Time to union and radiographic arthrosis at latest follow-up was assessed. Mean follow up was 7.7 months (range, 0.5-32.5 ).

Results: All patients achieved full composite flexion with pad-to-distal palmar crease distance=0 mm. Extensor lag resolved by 3 week follow up in all patients. All patients demonstrated full active MP extension or hyperextension at latest follow-up. Grip strength measured 103% (range, 58-230) of the contralateral hand. No secondary surgeries were performed. There were two cases of re- fracture following recurrent blunt impact trauma resulting in shaft refractures following prior radiographic evidence of full osseous union with the screw in place. All patients achieved radiographic union by 6 weeks. There was no radiographic arthrosis at latest follow-up. One patient reported an occasional click with MP motion that did not require further treatment. Summary Points: Limited open minimally invasive retrograde IMHS fixation is a safe and reliable technique for metacarpal neck/subcapittal and axially-stable shaft fractures; allows for early postoperative active motion without affecting union rates; obviates immobilization; and avoids complications associated with K-wire and plate/screw constructs. This technique offers distinct advantages in select patients (i.e. athletes). Technique, current indications, pearls and pitfalls are reviewed.

References: Reference 1: Ten Berg P; Mudgal CS; Leibman MI; Belsky MR; Ruchelsman DE. Quantitative 3D- CT analyses of intramedullary headless screw fixation for metacarpal neck fractures. Journal of Hand Surgery. 2013;38A:322-330.

Figure 1. (a) A limited-open extensor split approach is made with direct visualization of the starting point for retrograde screw insertion. (b,c) Closed reduction is confirmed under fluoroscopic guidance and a 1.1mm Kirschner wire is then inserted under direct visualization through the dorsal corridor of the metacarpal head in line with the medullary canal to achieve provisional fixation. The Kirschner wire is then over-drilled and replaced with a 2.4mm or 3.0mm cannulated headless compression screw (Synthes, Paoli, PA) based upon preoperative templating of the dimensions of the isthmus of the intramedullary canal. (d,e) Active and active-assisted range of motion are begun by post-operative day 5.

♦ No relevant financial relationships to disclose

E-poster 75: Establishment of biomarkers for discrimination between distal and proximal side of peripheral nerve degeneration & Development of an intraoperative impedance based-monitoring system for mapping of peripheral nerve injuries

Category: Evaluation/Diagnosis, Surgical Technique, Basic Science Keyword: Hand and Wrist, Elbow and Forearm, Shoulder and Arm, Nerve, Diseases and Disorders N/A - Not a clinical study

♦ Mohammad Reza Lornejad-Schäfer, PhD

Hypothesis: New appropriate, accurate and portable alternative measurement systems and biomarkers are needed which enable rapid intraoperative measurement of peripheral nerve (IOMPN) avoiding nerve damage and invasion to improve patient care. Hypothesis:Are MKP1 and HO-1 appropriate biomarkers for discrimination between distal and proximal side of peripheral nerve (PN) degeneration and is reflection coefficient S11 (dB) as function of frequency (Hz) an applicable non-invasive and label-free technique to map the nerve degeneration after nerve injury?

Methods: Degenerative process was induced in the PN. Fresh prepared PN in chicken legs were crushed 30 seconds by tweezers followed by 3h incubation on ice. The function and structure of PN during degeneration process have been investigated. Demyelinization of axon and structure of PN were tested using toluidine blue staining, protein expression of Mitogen-activated protein kinase phosphatase 1 (MKP1), Hemeoxygenase 1 (HO-1) and as control glyceraldehyde-3-phosphate dehydrogenase (GAPDH) using western blot analysis. MKP1 regulates MAP kinases that are involved as local sensors for axonal degeneration (Miller et al., 2009). HO-1 acts as inflammatory marker in response to nerve injury (Yasuhiro at al., 1998). Reflection coefficient S11 was measured using a network analyser and an electrode. The range between 10 kHz and 100 MHz is called ß-dispersion, which is associated with the dielectric properties of the cytoplasm- membrane interface, intracellular membrane structures, proteins and other organic macromolecules (Kyle et al., 1999).

Results: Toluidine staining of PN showed that structure of PN changed and axons were strongly demyelinated. The MKP1 protein expression increased in the crushed nerve. The distal side of the crushed nerve was marked by the rise of the HO-1 protein expression and remained proximal unchanged (figure 1). The PN degeneration process could be measured by S11 as a function of frequency. At a frequency of 5 MHz the S11 value increased in relation to the grade of nerve injury: semi-severed nerve (red line) > crushed nerve (blue line) > non-injured nerve (green nerve) (figure 2). These results were in accordance with the used biomarkers.

Summary Points: - HO-1 may be an appropriate biomarker for discrimination between the distal and proximal side of PN degeneration. - The reflection coefficient S11 related measurement system by means of high frequency technology with a suitable electrode can be used to map PN injury. - This measurement system may enable the discrimination between different grades of nerve injury.

References: Reference 1: Kyle AH, Chan CT, Minchinton AI. Characterization of three-dimensional tissue cultures using electrical impedance spectroscopy.Biophys J. 1999 May; 76(5):2640-8. Reference 2: Miller, B.R., C. Press, R.W. Daniels, Y. Sasaki, J. Milbrandt, A. DiAntonio. 2009. A dual leucine kinase-dependent axon self-destruction program promotes Wallerian degeneration. Nat. Neurosci. 12:387–389. Reference 3: Yasuhiro Itoa et al. 1998, Brain Research. Volume 793, Issues 1–2, 18 May 1998, Pages 321–327.

♦ No relevant financial relationships to disclose

E-poster 76: Effect of exendin-4, a long acting analogue of glucagon-like peptide-1 receptor agonist, on nerve regeneration after nerve crush injury.

Category: Treatment, Basic Science Keyword: Nerve N/A - Not a clinical study

♦ Koji Yamamoto, MD ♦ Masatoshi Amako, MD, PhD ♦ Hiroshi Arino, MD ♦ Tsukuru Nakaya, MD ♦ Yasufumi Hirahara, MD ♦ Koichi Nemoto, MD, PhD

Hypothesis: Exendin-4, a long acting analogue of glucagon-like peptide-1 receptor agonist, improves glycemic control in patients with type 2 diabetes mellitus. It has protective effect on the central and peripheral nervous system. We have already proved that exendin-4 administration could promote nerve regeneration after nerve crush injury. In the present study, we examined whether exendin-4 exerts its effect in dose dependent.

Methods: Sixty Wistar rats, 8 weeks old, were used. Rats were divided into 5 equal groups (n=12 in each group) as follows: (1) 0 µg (exendin-4) group. (2) 0.02 µg group. (3) 0.1 µg group. (4) 0.5 µg group. (5) 2.5 µg group. Right sciatic nerves were crushed using aneurysmal clip with a compression force of approximately 250g. We administered the designated dose of exendin-4 in each group during 14 days after the crush. Sciatic Functional Index (SFI) was measured every 3 days from 1 day till 28days postoperatively to evaluate the functional recovery. At 4 weeks postoperatively, distal latency of the sciatic nerve and amplitude of compound muscle action potential (CMAP) from the tibialis anterior muscle (TA) were measured by electrophysiological study. After the study, bilateral TA were harvested and weighed. Blood glucose levels were checked at 0, 1 and 3 days postoperatively. Simple correlation between the dose of exendin-4 and values of each parameter were assessed using Pearson's correlation coefficient.

Results: The SFI showed simple correlation between dose and SFI values (r=0.35 on 13 days and r=0.48 on 16 days, p<0.01). The electrophysiological study showed simple correlation between the distal latency and dose of exendin-4 (r=-0.41, p<0.05). However, it did not indicate simple correlation between the dose and the amplitude of CMAP (r=0.25, p=0.18). TA Ratio (injured side/uninjured side) indicated simple correlation with the dose (r=0.31, p<0.05). The blood glucose levels were normal at 0 (before crush), 1 and 3 days after the nerve crush in each group. There were no simple correlation between the dose and values blood glucose (r=-0.02 at 1 day and r=0.06 at 3 days).

Summary: Repeated injections of exendin-4 promote nerve regeneration after nerve crush injury and it exerts their effect in dose dependent.

References: Reference 1: Yamamoto K, Amako M, Yamamoto Y et al., "Therapeutic effect of exendin-4, a long-acting analogue of glucagon-like peptide-1 receptor agonist, on nerve regeneration after the crush nerve injury." Biomed Res Int. 2013;2013:315848. doi: 10.1155/2013/315848.

♦ No relevant financial relationships to disclose

E-poster 77: Passive Skeletal Muscle Excursion after Tendon Rupture Correlates with Increased Collagen Content in Muscle

Category: Basic Science Keyword: Diseases and Disorders N/A - Not a clinical study

♦ Yun-rak Choi, MD, PhD ♦ Ho Jung Kang, MD ♦ Il Hyun Koh, MD

Hypothesis: This study was designed to measure time-dependent changes in muscle excursion and collagen content after tenotomy and to analyze the correlation between muscle excursion and collagen content in a rabbit model.

Methods: Twenty-four rabbits underwent tenotomy of the second extensor digitorum longus (EDL) muscles on the right legs and were randomly assigned to three groups based on the period of time after tenotomy (2, 4, and 6 weeks). The second EDL muscles on left legs were used as controls. At the each time after tenotomy, passive muscle excursion and collagen content, determined by hydroxyproline content, were measured bilaterally, and the ratio of each value to the normal one was used.

Results: The mean ratio of muscle excursion after tenotomy to the value of the control decreased in a time-dependent fashion: 92.5% at 2 weeks, 78.6% at 4 weeks, and 55.1% at 6 weeks. The mean ratio of hydroxyproline content in muscle to the value of the control increased in a time- dependent fashion: 119.5% at 2 weeks, 157.3% at 4 weeks, and 166.6% at 6 weeks. There was a significant negative correlation between the ratio of hydroxyproline content in muscle after tenotomy to the control values and the ratio of muscle excursion after tenotomy to the control values (r = - 0.602, p = 0.0019).

Summary Points: The decrease in muscle excursion seems to correlate with the increase in collagen content in the muscle in a time-dependent fashion following tenotomy.

References: Reference 1: Jamali AA, Afshar P, Abrams RA, Lieber RL. Skeletal muscle response to tenotomy. Muscle Nerve 2000;23:851-62. Reference 2: Jozsa L, Kannus P, Thoring J, Reffy A, Jarvinen M, Kvist M. The effect of tenotomy and immobilisation on intramuscular connective tissue. A morphometric and microscopic study in rat calf muscles. J Bone Joint Surg Br 1990;72:293-7. Reference 3: Baker JH, Hall-Craggs EC. Changes in sarcomere length following tenotomy in the rat. Muscle Nerve 1980;3:413-6. Reference 4: Tasai AM JA, Abrams RA, Lieber RL. Skeletal muscle recovery following tenotomy and simulated seven day delayed tendon repair. Trans Orthop Res Soc 1998;23:1. Reference 5: Jeon SH, Chung MS, Baek GH, Lee YH, Gong HS. The effect of muscle excursion on muscle recovery after tendon repair in a neglected tendon injury: a study in rabbit soleus muscles. J Orthop Res 2011;29:74-8.

♦ No relevant financial relationships to disclose

E-poster 78: Efficacy of Forearm Band for Lateral Epicondylitis. –A Randomized Controlled Trial-

Category: Treatment, Therapy/Rehabilitation Keyword: Elbow and Forearm, Diseases and Disorders Level 2 Evidence

♦ Takanobu Nishizuka, MD ♦ Hitoshi Hirata, MD ♦ Michiro Yamamoto, MD, Ph.D ♦ Katsuyuki Iwatsuki, MD

Hypothesis: The objective of this prospective randomized study is to analyze the effect of the forearm band for the treatment of lateral epicondylitis with a prospective, randomized, controlled multicenter study. My hypothesis is that forearm band does not change prognosis of lateral epicondylitis.

Methods: A total of 101 patients with lateral epicondylitis were admitted to our 5 affiliated hospitals. Of these, 22 were lost to follow up. In total, 79 patients with 79 lateral epicondylitis were randomly allocated into 2 treatment groups. The band group (n=39) was instructed to wear a forearm band for more than 6 hours daily; for at least the first 6 months. Both the band group and the non-band group (n=40) were instructed to perform extensor stretching exercises three times daily for 6 months. There were 50 men and 29 women with a mean age of 58±9 (32-78). They were followed at first visit, after 1 month of treatment, then at 3 and 6 months. The primary outcome measure was Hand 10 score. The secondary outcomes were Pain VAS, physical examination, and satisfaction. Comparison of the band group and the non-band group addressed the effect of the forearm band. Student-T test and chi-square test were performed for each outcomes measure to assess differences between two groups at 1,3,6 months.

Results: Significant improvement of the Hand 10 score was found at 3 and 6months in the non-band group, whereas at only 6months in the band group (P<0.01). When comparing Hand 10 score between two cohort, there was no statistically significant difference at 1,3 and 6 months(P=0.14, 0.06, 0.27, respectively)(Figure1). Regarding Pain score, significant improvement was found in both groups at 6months after treatment (P<0.01). When comparing Pain score between two cohort, there was no statistically significant difference at 1,3, 6 months(P=0.26, 0.20, 0.26, respectively)(Figure2). When comparing the rate of positive physical examination such as tenderness, Thomsen test and middle finger extension test between two cohort, there was also no statistically significant difference at 1,3 and 6 months. The percentage of satisfactory patients in band group/non-band group were 70.8%/73.6% and 89.6%/92.8% at 3 and 6 months.

Summary Points: We compared Hand 10 score, Pain Score, physical examination results, and satisfaction between band group and non-band group until 6 months after enrollment. In conclusion, forearm band has little useful value on the clinical course of lateral epicondylitis with this randomized controlled trial.

References: Reference 1: Struijs P.A.A.; Orthotic devices for tennis elbow: a systematic review British Journal of General Practice, Volume 51, Number 472, November 2001, pp. 924-929(6) Reference 2: Solveborn SA : Radial epicondylalgia(tennis elbow):treatment with stretching or forearm band. A prospective study with long-term follow-up including range-of-motion measurements. Scand J Med Sci Sports 7(4) : 229-237,1997

♦ No relevant financial relationships to disclose E-poster 79: The Effect of Immunosuppression on Allograft Motor Nerve Regeneration

Category: Basic Science Keyword: Nerve N/A - Not a clinical study

♦ Jong Pil Kim, MD ♦ Patricia F Friedrich, AAS ♦ Alexander Y Shin, MD ♦ Allen T Bishop, MD

Hypothesis: Clinical success of composite tissue allotransplantation (CTA) is dictated not only by graft acceptance and survival but also by nerve regeneration. We hypothesized that triple immunosuppression protocols currently used for CTA will have the best effect on the recovery of motor function following segmental nerve allograft reconstruction.

Methods: Eighty-eight Lewis rats underwent bridged allograft with the sciatic nerve from Brown Norway rat and were randomly divided into four experimental groups. All groups were administered medications daily via a subcutaneous route. Group I received 0.9% isotonic saline solution (control); group II, 2 mg/kg FK 506; group III, 1 mg/kg FK506 combined with 15 mg/kg mycophenolate mofetil hydrochloride (MMF); and group IV, 2 mg/kg FK506 combined with 30 mg/kg MMF and prednisone. After twelve weeks, recovery of motor function was evaluated by isometric tetanic force measurement and wet muscle weight of the tibialis anterior muscle, ankle contracture angle, electrophysiologic parameters, and peroneal nerve histomorphometry. Adequacy of immunosuppression was monitored by a transplanted skin graft from the Brown Norway rat to the Lewis rat.

Results: At twelve weeks, an analysis of isometric tetanic force revealed significant functional recovery in all groups treated with FK506 compared with the control, but no difference was observed between the immunosuppression groups: the mean recovery rate of isometric tetanic force was 42.1 ± 6.4% for group I, 56.1 ± 12.4% for group II, 58.4 ± 10.7% for group III, and 61.3 ± 11.2% for group IV. Group IV was statistically superior to all other groups with regard to ankle contracture and compound muscle action potential(Fig.1), but histomorphometry did not differ significantly among the groups.(Fig. 2)

Summary Points: 1.FK506 immunosuppressant significantly enhanced motor recovery after allograft nerve reconstruction of the sciatic nerve. However, high dose of FK506 with or without MMF and corticosteroid did not result in superior recovery of motor function compared with low dose of FK506 combined with MMF. 2. The effect of motor recovery after low dose FK506 immunosupppression combined with MMF are comparable with the high dose of triple immunosuppressant, which may have a higher probability of clinical performance after CTA when the early rejection can be detected and appropriately salvaged 3. Differences were not demonstrated between the immunosuppression groups in this rat model with respect to motor nerve regeneration, which will allow surgeons to choose the optimal doses of immunosuppressants for allograft reconstruction of the motor nerve in combination with other transplanted tissues.

References: Reference 1: Cottrell BL, Perez-Abadia G, Onifer SM, Magnuson DS, Burke DA, Grossi FV, Francois CG, Barker JH, Maldonado C. Neuroregeneration in composite tissue allografts: effect of low- dose FK506 and mycophenolate mofetil immunotherapy. Plastic and reconstructive surgery. 2006;118:615-23; discussion 24-5. Reference 2: Rustemeyer J, Dicke U. Allografting combined with systemic FK506 produces greater functional recovery than conduit implantation in a rat model of sciatic nerve injury. Journal of reconstructive microsurgery. 2010;26:123-9. Reference 3: Jensen JN, Brenner MJ, Tung TH, Hunter DA, Mackinnon SE. Effect of FK506 on peripheral nerve regeneration through long grafts in inbred swine. Annals of plastic surgery. 2005;54:420-7. Reference 4: Doolabh VB, Mackinnon SE. FK506 accelerates functional recovery following nerve grafting in a rat model. Plastic and reconstructive surgery. 1999;103:1928-36. Reference 5: Comparison of continuous and discontinuous FK506 administration on autograft or allograft repair of sciatic nerve resection. Muscle & nerve. 2004;29:812-22. Reference 6: Giusti G, Willems WF, Kremer T, Friedrich PF, Bishop AT, Shin AY. Return of motor function after segmental nerve loss in a rat model: comparison of autogenous nerve graft, collagen conduit, and processed allograft (AxoGen). The Journal of bone and joint surgery. American volume. 2012;94:410-7 Reference 7: Shin RH, Friedrich PF, Crum BA, Bishop AT, Shin AY. Treatment of a segmental nerve defect in the rat with use of bioabsorbable synthetic nerve conduits: a comparison of commercially available conduits. The Journal of bone and joint surgery. American volume. 2009;91:2194-204. Reference 8: Lee JY, Giusti G, Friedrich PF, Archibald SJ, Kemnitzer JE, Patel J, Desai N, Bishop AT, Shin AY. The effect of collagen nerve conduits filled with collagen-glycosaminoglycan matrix on peripheral motor nerve regeneration in a rat model. The Journal of bone and joint surgery. American volume. 2012;94:2084-91. Reference 9: Gold BG, Katoh K, Storm-Dickerson T. The immunosuppressant FK506 increases the rate of axonal regeneration in rat sciatic nerve. The Journal of neuroscience : the official journal of the Society for Neuroscience. 1995;15:7509-16. Reference 10: Konofaos P, Terzis JK. FK506 and nerve regeneration: past, present, and future. Journal of reconstructive microsurgery. 2013;29:141-8.

♦ No relevant financial relationships to disclose

E-poster 80: Effect of different wrist positions on distal radioulnar joint stability: A biomechanical study

Category: Basic Science Keyword: Hand and Wrist, Practice Management N/A - Not a clinical study

♦ Akio Iida, MD ♦ Shohei Omokawa, MD,PhD ♦ Hisao Moritomo, MD, PhD ♦ Mitsuhiro Aoki, MD ♦ Shinsuke Omori, MD ♦ Yasuhito Tanaka, MD/PhD

Hypothesis: Previous clinical study suggested that distal radioulnar joint (DRUJ) stability alters in different wrist positions. In the current cadaveric study, we hypothesized that DRUJ stability would increase in specific wrist positions in the normal and the triangular fibrocartilage complex (TFCC) sectioned wrists.

Methods: Nine fresh-frozen cadaver upper extremities were used. The humerus and ulna were fixed to the testing apparatus with the elbow at 90 degree flexion, and the radius was allowed to translate palmer and dorsal directions freely relative to the ulna (Figure 1). Testing was performed by translating the radius relative to the ulna with the wrist fixed in five positions (neutral, 70 degrees of extension, 70 degrees of flexion, 20 degrees of radial deviation, 40 degrees of ulnar deviation) under a load of 2 kgf in each palmar and dorsal direction. A three-dimensional space electromagnetic tracking device was used for measurement of displacement of the radius. We analyzed the dorsopalmer displacement in intact wrists and after sequential sectioning of ulnocarpal ligament (UCL), radioulnar ligament (RUL) at the ulnar insertions and extensor carpi ulnaris (ECU) floor. A one-way ANOVA with repeated measures and Bonferroni-Holm post-hoc test was used to determine differences between five wrist positions in each sectioning stage.

Results: In the TFCC intact wrists, the displacement in wrist extension was significantly lower than that in neutral position (1.9mm smaller from neutral). After UCL sectioning, the displacement was no longer any significant differences. Under additional RUL sectioning, the displacement in extension and radial deviation was significantly lower than that in neutral position (1.6mm and 3.7mm smaller from neutral). Following ECU floor sectioning, the gross displacement was observed regardless of wrist positions. However, there were no longer any significant differences in this sectioning stage (Table 1). Summary Points 1) In the TFCC intact wrists, DRUJ was stabilized in extension, and this stabilization is possibly due to tightening of the UCL. 2) Although DRUJ instability occurred after complete RUL sectioning, DRUJ was mainly stabilized in radial deviation when the continuity of the ECU floor was preserved. 3) The current cadaveric study suggested that assessment of manual stress test of the DRUJ in wrist extension and radial deviation may provide additional information related to the concomitant injury of the UCL and ECU floor in the TFCC injured wrists.

References: Reference 1: L. Sanz, R. Dias and, C. Heras-Palou :A MODIFICATION OF THE BALLOTTEMENT TEST IN THE ASSESSMENT OF DISTAL RADIOULNAR JOINT INSTABILITY. J Bone Joint Surg Br 2009 vol. 91-B no. SUPP I 80

Table 1 Magunitude of Dorsal/palmar translation (n=9)

Neutral Extension Flextion Radial deviation Ulnar deviation Mean mm (SD) Mean mm (SD) Mean mm (SD) Mean mm (SD) Mean mm (SD) Intact 6.7 (2.3) 4.8 (2.0)§ 6.9 (2.4) 5.2 (2.3) 5.9 (2.6) UCL cut 6.7 (2.5) 6.6 (3.0) 7.1 (2.2) 6.2 (2.8) 6.9 (2.8) RUL cut 13.3 (3.5) 11.7 (3.2)§ 13.6 (3.4) 9.6 (3.5)§ 13.5 (3.4) ECU floor cut 20.4 (6.5) 20.9 (6.7) 20.6 (6.8) 20.5 (6.9) 21.0 (6.5) UCL: ulnocarpal ligament, RUL: radioulnar ligament, ECU: extensor carpi ulnaris §Indicates data that are significantly different from that of neutral in the same row

♦ No relevant financial relationships to disclose

E-poster 81: Opportunistic Osteoporosis Screening: Gleaning Additional Information from Diagnostic Wrist CT Scans

Category: Evaluation/Diagnosis, Prognosis/Outcomes Keyword: Hand and Wrist, Diseases and Disorders, General Principles N/A - Not a clinical study

♦ Joseph J Schreiber, MD ♦ Elizabeth B Gausden, MD ♦ Michelle Gerwin Carlson, MD ♦ Paul A. Anderson, MD ♦ Andrew J. Weiland, MD

Hypothesis: Hounsfield Unit (HU) values can be easily obtained from diagnostic CT scans to calculate regional bone density. In the spine, correlations between HU and T scores, bone density, compressive strength, and fracture risk have been firmly established1,2, as have thresholds for diagnosis of osteoporosis and osteopenia1,3. Although screening for osteoporosis and treatment have been shown to decrease the risk of distal radius fracture4, these rates remain disappointingly low5,6. We hypothesized that HU values of the distal radius could be used to assess local bone quality and would be predictive of distal radius fracture risk, thereby allowing identification of patients in need of further management.

Methods: Quantitative CT scans were performed in 100 patients and bone density measurements were made using regional cancellous bone HU values of the distal radius, ulna and capitate (Figure 1). 25 male and 25 female patients with an acute CT documented distal radius fracture were compared with age-matched controls that had a CT scan obtained for other indications.

Results: In both male and female cohorts, patients with a distal radius fracture had significantly lower regional bone density, as assessed with HU, at the distal radius, the ulnar head, and within the capitate as compared to non-fracture controls (P<0.0001, Figure 2). In females, a HU threshold of 218 in the distal radius optimized sensitivity (96%) and specificity (72%), and patients below this threshold were at increased risk of distal radius fracture (OR=3.4,P<0.001). In males, a HU value of 246 optimized sensitivity (88%) and specificity (84%) (OR=5.5,P<0.001). Control patients showed an age related decline in distal radius bone density (P<0.01), whereas fracture patients had low HU values regardless of age.

Summary Points: - HU measurements can be obtained from any diagnostic CT scan using modern software programs, and can be obtained by hand surgeons in the office setting with minimal effort, at no additional cost or radiation to the patient. - Patients with a distal radius fracture had lower bone density, as assessed with HU, in the distal radius, ulna, and capitate. - A distal radius HU value below 218 in females and below 246 in males was identified that is associated with a significantly increased risk for distal radius fracture. - We suggest that patients with HU values below these thresholds, regardless of imaging indications, be considered for further metabolic bone disease work up, such as additional imaging, laboratory assessments, initiation of treatment, or appropriate referral.

References: Reference 1: Schreiber JJ, Anderson PA, Rosas HG, Buchholz AL, Au AG. Hounsfield units for assessing bone mineral density and strength: a tool for osteoporosis management. The Journal of bone and joint surgery. American volume. 2011;93(11):1057-1063. Reference 2: Meredith DS, Schreiber JJ, Taher F, Cammisa FP, Jr., Girardi FP. Lower preoperative Hounsfield unit measurements are associated with adjacent segment fracture after spinal fusion. Spine. 2013;38(5):415-418. Reference 3: Pickhardt PJ, Pooler BD, Lauder T, del Rio AM, Bruce RJ, Binkley N. Opportunistic screening for osteoporosis using abdominal computed tomography scans obtained for other indications. Annals of internal medicine. 2013;158(8):588-595. Reference 4: Harness NG, Funahashi T, Dell R, et al. Distal radius fracture risk reduction with a comprehensive osteoporosis management program. The Journal of hand surgery. 2012;37(8):1543-1549. Reference 5: Rozental TD, Makhni EC, Day CS, Bouxsein ML. Improving evaluation and treatment for osteoporosis following distal radial fractures. A prospective randomized intervention. The Journal of bone and joint surgery. American volume. 2008;90(5):953-961. Reference 6: Freedman KB, Kaplan FS, Bilker WB, Strom BL, Lowe RA. Treatment of osteoporosis: are physicians missing an opportunity? The Journal of bone and joint surgery. American volume. 2000;82-A(8):1063-1070.

Figure 1. A. Technique for obtaining regional HU from the distal radius and distal ulna at the level of the sigmoid notch. Cancellous bone regional density is assessed using standard radiology software. In the control patient (37 year old female), note the high trabecular density as compared to the fracture patients in B and C. B. HU measurements in a minimally displaced distal radius fracture in a 33 year old female. Radiographic signs of osteoporosis are noted, including lower attenuation, decreased trabecular density, and apparent cortical thinning. C. HU measurement technique used in a comminuted distal radius fracture. D. HU measurement in the capitate.

Figure 2. Comparison of mean Hounsfield Unit values at the distal radius, ulna, and capitate measured in a distal radius fracture cohort (n=50) as compared to a control cohort (n=50).

♦ No relevant financial relationships to disclose

E-poster 82: The effect of Platelet Rich Plasma on adipogenesis and myogenesis in C2C12 myoblast cells

Category: Treatment, Basic Science Keyword: Hand and Wrist, Shoulder and Arm N/A - Not a clinical study

♦ Fumiaki Takase, MD ♦ Takeshi Kokubu, MD ♦ Yutaka Mifune, MD ♦ Atsuyuki Inui, MD ♦ Takako Kanatani, MD ♦ Issei Nagura, MD

Hypothesis: Muscle atrophy and fatty degeneration may occur with long time external fixation, such as after tendon repair surgery. Platelet rich plasma (PRP) has been reported to suppress adipogenesis within the marrow and to enhance tissue repair processes. Our hypothesis is PRP has an inhibitional effect on adipogenesis and promoting effect on proliferation and myogenesis in C2C12 myoblast cells.

Methods: Cell Culture A murine myogenic cell line, C2C12 was maintained in DMEM supplemented with 10% FBS (regular medium). For adipogenesis, StemMACS AdipoDiff Media was used, and DMEM without FBS was used for myogenesis. The cells were cultured in five different medium as below; Regular medium only (group C), adipogenic medium only (group A), adipogenic medium with 10% PRP (group A+P), myogenic medium only (group M), and myogenic medium with 10% PRP (group M+P). Assessment of the adipogenic differentiation At day 3, real-time PCR was performed using PPAR? and C/EBPa as adipogenic marker. At day 7, oil-red O staining was performed. Assessment of the proliferation and myogenic differentiation Cell viability was measured by WST method at 12 and 24 hours. At day 3, real-time PCR was performed using MyoD and Myogenin as myogenic markers. At day 7, cell morphology was observed and assessed by immunocytochemistry with anti myosin-heavy-chain antibody.

Results: Adipogenic differentiation PPAR? and C/EBPa gene expression in the group A+P was decreased compared to the group A. Oil-red O staining showed that lipid droplet emerged in the group A, and the formation of the that was suppressed in the group A+P (Fig.1). Proliferation and myogenic differentiation C2C12 showed extensive myotube formation in the group M. In the group M+P, the size and volume of myotubes were suppressed. Immunocytochemistry showed the same tendency as cell morphology assessment. MyoD and Myogenin gene expression in the group M+P was decreased compared to the group M. Regarding cell viability, there was no significant difference between the group M+P and M at 12h, but it was significantly increased in the group M+P than that of the group M at 24h.

Summary Points: Our study indicated that PRP has an inhibitory effect on adipogenic change of C2C12 myoblast cells. The result showed the possibility of the PRP to prevent fatty degeneration of muscle. On the other hand, PRP have no promoting effect on myogenic differentiation of myoblast, but has a promoting effect on cell proliferation. The result implied the possibility that PRP was effective to the early stage of muscle regeneration.

References: Reference 1: Barry et al; Journal of Shoulder and Elbow Surgery(2013) Reference 2: Gerber et al; J Bone Joint Surg Am(2000) Reference 3: Liu HY et al; Biomaterials(2011)

♦ No relevant financial relationships to disclose

E-poster 83: Comparison of Surgical Treatments for Multiple Extensor Tendon Ruptures in Rheumatoid Hands: a retrospective study of 48 cases.

Category: Treatment Keyword: Hand and Wrist Level 3 Evidence

♦ Taku Suzuki, MD, PhD ♦ Takuji Iwamoto, MD, PhD ♦ Kazuki Sato, MD, PhD ♦ Toshiyasu Nakamura, MD, PhD ♦ Hiroyasu Ikegami, MD, PhD ♦ Yoshiaki Toyama, MD, PhD

Hypothesis: Subcutaneous multiple extensor tendon ruptures of rheumatoid hands are relatively rare. Therefore, there have been few previous reports on these conditions, which made it difficult to compare several treatment options. The aim of this study was to evaluate surgical outcomes of the several reconstructions for multiple extensor tendon ruptures in rheumatoid arthritis (RA) patients.

Methods: Forty-eight RA patients with 3 fingers extension loss were reviewed retrospectively for this study. Four surgical procedures were applied for the reconstruction; Palmaris longs (PL) tendon grafting, extensor indicis proprius (EIP) tendon transfer, end-to-side transfer to the intact extensor tendon with the tension-reduced early mobilization, combination of EIP tendon and end-to-side transfer. The post-operative range of motion (extension lag, flexion, arc) of the MP joint was measured and clinical outcome was evaluated.

Results: Combination (end-to-side and EIP transfer) group demonstrated significant lowest (best) extension lag of the MP joint (-3°) compared to PL grafting group (-21°) (P = 0.007). Most favorable outcome of the MP joint flexion was obtained by end-to-side transfer group (74°), which is significantly superior to EIP transfer group (62°) (P = 0.019). Significant good arc of MP joint was achieved by combination (66°) and end-to-side transfer (63°) group compared to PL grafting group (42°) (P = 0.004). Combination group provided satisfactory clinical outcomes: excellent in 7 cases (47%) and good in 6 cases (40%). Significant difference was recognized between combination and PL grafting group (P = 0.012).

Summary Points: Combination of end-to-side transfer to the adjacent tendon and EIP transfer is useful procedure in case of 3 fingers extension loss. End-to-side transfer with the tension-reduced early mobilization is effective treatment to prevent extension contracture.

♦ No relevant financial relationships to disclose

E-poster 84: Results of the Universal-2 total wrist arthroplasty in patients with post-traumatic wrist osteoarthritis.

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist Level 3 Evidence

♦ Michelle Brinkhorst, MD

Hypothesis: Most studies concerning newer (fourth) generation wrist prostheses have focused on patients with rheumatoid arthritis(RA) and older generation wrist prostheses (1). As a result, the treatment of choice for end-stage wrist osteoarthritis is total wrist arthrodesis. Therefore, we retrospectively evaluated the clinical results of the newer – fourth-generation – Universal 2 Total Wrist System in post-traumatic osteoarthritis (PTOA) patients.

Methods: Twelve PTOA patients were clinically evaluated pre-operatively, and 6 and 12 months after surgery on range of motion (ROM), grip strength and DASH score. To relate these findings to current literature, results were compared with reference data for wrist function of healthy controls (2)and outcome of the same prosthesis in 9 RA patients.

Results: In PTOA patients, 6 and 12 month after the Universal 2 prosthesis was placed, radial deviation was significantly reduced (P<0.001 and P=0.019, respectively) compared to baseline (Fig. 1). All other ROM directions did not change significantly. Compared to healthy controls, PTOA patients had a reduced ROM in all directions both before and after surgery. Grip strength did not change significantly at 6 and 12 months compared to baseline and was approximately 30% of the healthy controls. DASH score significantly decreased from 46 to 32 points at 6 months (p=0.001) and to 26 at 12 months (p<0.001). At 12 months, DASH score was almost comparable to DASH score in healthy controls (range 11 to 21 points)(Fig. 2). Compared to RA patients, pre-operative radial deviation was larger in PTOA patients than in RA patients (12.9° versus 7.2°) while all other ROM measures and grip strength did not differ importantly between groups. However, DASH scores were lower during all 3 time points in PTOA patients than in RA patients (pre-operatively: 46 versus 69 points and at 12 months: 26 versus 50 points).

Summary Points: - Clinical outcome and patient-reported outcome showed satisfactory results in end-stage PTOA patients that were treated with a Universal 2 Total Wrist System. - Results were comparable to outcome obtained in RA patients, although DASH scores were better at follow-up in PTOA patients. - Relatively good DASH score combined with the partly-maintained wrist ROM indicates that reconstruction with the Universal 2 Total wrist prosthesis should be considered in patients with end-stage post-traumatic wrist osteoarthritis - Although short term results of this fourth generation implant suggest significant improvement compared to older generation implants, longer follow-up periods are needed to clarify their survival rate.

References: Reference 1: Cavaliere CM,Chung KC: A systematic review of total wrist arthroplasty compared with total wrist arthrodesis for rheumatoid arthritis. Plast Reconstr Surg 2008;122:813-25 Reference 2: Klum M,Wolf MB,Hahn P,Leclere FM,Bruckner T,Unglaub F: Normative data on wrist function. J Hand Surg Am 2012;37:2050-60.

♦ No relevant financial relationships to disclose

E-poster 85: Iatrogenic Peripheral Nerve Injuries Caused by Surgical Procedure

Category: Treatment Keyword: Nerve Level 3 Evidence

♦ Kazuki Sato, MD, PhD ♦ Takuji Iwamoto, MD, PhD ♦ Noboru Matsumura, MD, PhD ♦ Yoshiaki Toyama, MD, PhD ♦ Toshiyasu Nakamura, MD, PhD

Hypothesis: The purpose of this study is to examine the causes of iatrogenic peripheral nerve injuries in patients who underwent reconstructive surgery in our hospital. Our report focuses on possible strategies for the treatment of iatrogenic peripheral nerve injuries.

Methods: From 1997 to 2011, 43 cases of iatrogenic peripheral nerve injury caused by surgical procedure were treated. Patients underwent electrophysiologic examination with electromyography, as well as physical examination. The average age at the time of reconstructive surgery was 50 years (range, 12-81 years). The average time between the injury and the treatment was 11 months (range, 3 days-5 years). The average follow-up period was 2.8 years. The most frequent causes of nerve injury were “resection” of schannoma (12 cases). Other causes were osteosynthesis (7 cases), soft tissue tumor resection (5 cases), cervical lymph node biopsy (4 cases), release of de Quervain tenosynovitis (3 cases) and trigger finger (2 cases), and others (10 cases). Injured nerves consist of ulnar nerve (11 cases), brachial plexus, radial nerve (7 cases, each), digital nerve (5 cases), accessary nerve (4 cases), median nerve (2 cases), and others (6 cases). Surgical reconstruction was accomplished by nerve graft in 26, neurolysis in 9, nerve suture in 5, and nerve transfer in 3. Sensibility was evaluated using Seddon’s scale and muscle function was determined using a scale defined by the British Medical Research Council.

Results: Of the 37 patients with sensory nerve injury, five patients were fully satisfied with the recovery (S4), and twenty reported a recovery of sensibility (S3). In 9 patients a slight superficial sensitivity was noted (S2). In 2 patients there was deep skin sensitivity (S1), and anesthesia was diagnosed in 1 (S0). Of the 28 patients with motor nerve injury, 3 patients fully recovered to their original condition (M5). In 12 patients, motor ability against resistance was observed (M4); 8 patients were able to move against gravity (M3); 4 patients were able to move without gravity (M2); and contractility of the muscles without the ability to move was observed in 1 (M1). Twenty patients (47%) who underwent reconstructive surgery within a six-month period after iatrogenic injury were treated successfully. These results suggest that timely treatment is decisive for good outcome.

Summary Points: 1. Most iatrogenic peripheral nerve injuries may be preventable by an adequate knowledge of surgical anatomy and awareness of the type of procedures. 2. An important factor in treatment is the time between injury and appropriate treatment.

References: Reference 1: Sunderland S. Nerve injuries and their repair. 2nd ed. Edinburgh: Churchill Livingstone; 1991:91-114. Reference 2: Komurcu F, Zwolak P, Benditte-Klepetko H, Deutinger M. Management strategies for peripheral iatrogenic nerve lesions. Ann Plast Surg. 2005;54:135-9.

♦ No relevant financial relationships to disclose

E-poster 86: Elbow Arthroscopy Complications

Category: Surgical Technique, Historical Information, Prognosis/Outcomes, Patient Education Keyword: Elbow and Forearm Level 4 Evidence

♦ Peter Hutchinson, MD ♦ Charles Cassidy, MD ♦ Hervey Kimball, MD

Hypothesis: There is a high rate of complications associated with elbow arthroscopy. Methods: A retrospective review of all elbow arthroscopies performed by two surgeons at two institutions (New England Baptist Hospital & Tufts Medical Center) during a 10 year period, from January 1st, 2001 – December 31st, 2011 was performed. 363 patients were identified and adequate data was available for 336 (92.6%) to assess early postoperative complications. Further data analysis was performed for 257 cases (70.8%) with follow up greater than 6 weeks postop. For these patients, the average follow up was 145 days. The average age of patients was 40.2 years (range 10-83). 31% of cases were performed on women. The most common diagnoses included epicondylitis, osteoarthritis, inflammatory arthritis, synovitis, plica, loose bodies, OCD lesions, and contractures.

Results: Major complications occurred after 1.5% of arthroscopies including nerve palsy and contracture (2 ulnar neuropathies and 2 cases motion loss requiring additional surgery). Minor complications occurred after 21% of arthroscopies (42 with motion loss of 30 degrees or less, 6 transient paresthesias, 4 portal seromas without drainage, one calcific body in the portal area, and one superficial infection treated with antibiotics). The average loss of motion was 10.6 degrees in the 42 patients with motion loss less than 30 degrees. The overall average change in motion for all cases was two degrees of motion gain. Rate of minor non motion complications showed a trend downward over the ten year period.

Summary Points: The complication rates for elbow arthroscopy in this study were found to be higher than in the study by Kelly et al. However the types of complications have shifted. We experienced no joint infections or portal drainage problems in this study which were problems found by Kelly et al. We also similarly noted very few nerve related complications. The majority of our complications were related to post-operative motion loss. This suggests that while the arthroscopic techniques may have become safer, surgery about the elbow still carries significant risks of stiffness.

References: Reference 1: Kelly EW, Morrey BF, O'Driscoll SW. Complications of Elbow Arthroscopy. J Bone Joint Surg Am. 2001 Jan;83-A(1):25-34

♦ No relevant financial relationships to disclose

E-poster 87: Comparison of Dorsal and Volar Plating Techniques for Ulnar Shortening Osteotomy

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist, Diseases and Disorders Level 3 Evidence

♦ Soumen Das De, MD, MPH

Hypothesis: The reported incidence of hardware-related complications after ulnar shortening osteotomy (USO) for ulnar impaction syndrome using volar- or ulnar-positioned plates is as high as 55%. Utilizing a smaller, dorsally applied plate will reduce the incidence of soft tissue irritation and the need for subsequent hardware removal.

Methods: A retrospective review of forty USO in 38 patients performed by the same surgeon over a 10- year period. The mean age was 44.8 (SD, 2.5) years and there were 17 males and 21 females. The mean pre-operative ulnar variance was +3.0 (SD, 0.3) mm. The median follow-up was 10.4 months (range: 1.4 – 57.6). Functional outcome was assessed using the Patient-Rated Wrist Evaluation (PRWE) score. Other outcomes of interest were: range of motion (ROM), union, grip strength and complications. A minimum follow-up of 3 months was used to assess these outcomes and 5 cases were excluded from the analysis.

Results: There were 16 dorsal plates and 19 volar plates. The mean PRWE score was 11.8 (SD, 3.4) in the “dorsal” group and 14.8 (SD, 3.0) in the “volar” group (p = 0.52). There was no difference in ROM between the two groups. The grip strength compared to the contralateral upper extremity in the “dorsal” group was higher than the “volar” group (101% versus 71%, p = 0.01). There were 3 (19%) complications in the “dorsal” group and 10 (53%) in the “volar” group. Complications in the “dorsal” group were: painful hardware (2) and progressive radiocarpal arthritis in one patient. Complications in the “volar” group were: painful hardware (6), non-union (1), wound infection (1), osteolysis of the proximal row (1), and radio-ulnar contracture (1). Secondary procedures (including removal of symptomatic hardware) were required in 2 (13%) patients in the “dorsal” group and 8 (42%) in the “volar” group. Notably, there were no cases of ECU tendinitis in the “dorsal” group.

Summary Points: • USO with volar plating was associated with a higher incidence of soft tissue irritation requiring secondary surgery • A smaller, dorsally applied plate provided the same rigidity of fixation with less soft tissue complications and no delayed / non-unions • The technique is easy to replicate and does not require specialized equipment

♦ No relevant financial relationships to disclose

E-poster 88: Biomechanical Evaluation of Scaphoid and Lunate Kinematics following Sectioning only the Dorsal SLIL, only the Volar SLIL and all of the SLIL

Category: Evaluation/Diagnosis, Treatment, Basic Science Keyword: Hand and Wrist N/A - Not a clinical study

♦ Michael S Waters, MD ♦ Frederick W Werner, MME ♦ Stafanos F Haddad, BS ♦ Michael L McGrattan, B.S. ♦ Walter H Short, MD

Hypothesis: A torn scapholunate interosseous ligament (SLIL) may result in wrist instability. Clinical symptoms include pain and diminished function. Surgical repairs have either focused on repairing the dorsal portion of the ligament or tendon weaves attempting to restore the entire ligamentous complex. This study evaluates the relative importance of the dorsal and volar portion of the SLIL in stabilizing the joint. We hypothesized that the volar SLIL has an equal or relatively more important role.

Methods: Sixteen fresh frozen cadaver wrists were moved through flexion-extension, radioulnar deviation and dart throw motions using a wrist joint motion simulator. During each wrist motion, electromagnetic sensors measured the motion of the scaphoid and lunate. Data was collected with the wrist intact and after randomly sectioning either the dorsal SLIL first (8 wrists) or the volar SLIL first (8 wrists) before completely sectioning the SLIL. The percent changes in both scaphoid and lunate flexion-extension and radioulnar deviation following selective dorsal or volar SLIL hemisectioning versus complete SLIL sectioning were analyzed using a t-test with significance set at 0.05.

Results: During all 3 wrist motions, selective sectioning of either the volar or dorsal SLIL caused an increase in both scaphoid flexion and lunate extension, however, selective dorsal SLIL sectioning caused a significantly greater increase in scaphoid flexion (P<0.04) and lunate extension (P<0.04) compared to first sectioning the volar SLIL (table 1, figure 1). Selective dorsal sectioning also caused a significantly greater increase in scaphoid ulnar deviation (P<0.01) during wrist flexion and radioulnar deviation, but not dart throw. Immediate sectioning of the dorsal SLIL caused 34 to 61% of the change seen with completely sectioning of both structures.

Summary Points: 1. The dorsal SLIL may have a more important role than the volar SLIL in stabilizing the scaphoid and lunate, although the volar component does contribute to stability of the joint. 2. In the presence of a torn dorsal SLIL, an intact volar SLIL continues to provide initial stability to the scapholunate articulation. 3. The stabilizing role of the volar SLIL should not be ignored in the presence of a torn dorsal SLIL. Verifying the integrity of or repairing/reconstructing the volar SLIL may aid in stability and improve surgical outcomes.

Table 1 Percent increase in carpal motion with SLIL hemisectioning (volar or dorsal) compared to complete SLIL sectioning Flexion-extension Radioulnar deviation Dart throw motion motion motion Only dorsal Only volar Only dorsal Only volar Only dorsal Only volar SLIL cut SLIL cut SLIL cut SLIL cut SLIL cut SLIL cut Increase in 33.6 9.9 43.0 3.5 41.9 12.6 scaphoid flexion Increase in 46.6 21.1 54.4 22.5 45.4 16.5 lunate extension Increase in 47.3 12.3 61.3 13.5 47.5 8.4 scaphoid ulnar deviation

♦ No relevant financial relationships to disclose

E-poster 89: Open Repair of Complete Radioulnar Ligament Tear Associated with Unstable Distal Radius Fractures

Category: Treatment Keyword: Hand and Wrist Level 2 Evidence

♦ Ryotaro Fujitani, MD ♦ Shohei Omokawa, MD,PhD ♦ Akio Iida, MD ♦ Yoshihiro Dohi, PhD ♦ Yasuhito Tanaka, MD/PhD

Hypothesis: We hypothesized that complete disruption of radioulnar ligament tears may lead to postoperative distal radioulnar joint (DRUJ) instability and ulnar wrist pain. We prospectively conducted early diagnosis and open reattachment at the fovea simultaneously with distal radius fracture (DRFx) fixation.

Methods: Between 2004 and 2012, 346 consecutive patients (mean age 64years) who had unstable DRFx were prospectively enrolled in this study. All patients treated with volar plating or intramedullary nailing. After DRFx fixation, if the DRUJ was judged to have ligamentous instability, the joint was explored by open surgery. Radiographic, objective and subjective outcomes of the ulnar wrist were evaluated at the 1-year follow-up. Radiographic outcomes included DRUJ gap distance and arthritic change graded according to Knirk and Jupiter criteria. Objective examination included the DRUJ instability, the range of wrist motion and grip strength. Ulnar wrist pain (VAS), presence or absence of sense of instability and DASH questionnaire were used to evaluated the subjective outcome. The Cooney’s wrist score was also calculated.

Results: We confirmed 22 patients with a complete tear of TFCC at the fovea. Of these patients, 19 patients were diagnosed as having DRUJ instability during the initial distal radius fracture surgery via manual testing, and three patients were diagnosed in the postoperative period. There was a significant difference between the average DRUJ Gap distance at injury (4.9 mm) and that 1-year follow-up period (1.3mm) (p<0.05). No patient had developed the OA in DRUJ. One patient had objective and subjective DRUJ instability at the 1-year follow-up. The mean range of flexion- extension, supination-pronation and grip strength was 93%, 87% and 85% of the contralateral side, respectively. Mean ulnar wrist pain (VAS) was 5.1mm and DASH score was 13. According to Cooney’s wrist score, the result considered to be excellent in 20 patients and good in two.

Summary Points: 1. 22 of 346 (6.4%) patients who had unstable DRFx had complete tears of the TFCC at its foveal insertion of the ulnar head. 2. The DRUJ Gap distance at injury of the 22 patients with complete tears averaged 4.9 mm, and restored to 1.3mm at the final-follow-up. 3. Early diagnosis and open reattachment at the fovea simultaneously with DRFx fixation can successfully stabilize DRUJ instability and obtain good functional results.

References: Reference 1: Fujitani R, Omokawa S, Akahane M, Iida A, Ono H, Tanaka Y. Predictors of distal radioulnar joint instability in distal radius fractures. J Hand Surg 2011, 36A: 1919-1925. Reference 2: Knirk JL, Jupiter JB. Intra-articular fracture of the distal end of the radius in young adults. J Bone and Joint Surg 1986; 68A: 647-659. Reference 3: Lindau T, Adlercreutz C, Aspenberg P. Peripheral tears of the triangular fibrocartilage complex cause distal radioulnar joint instability after distal radial fractures. J Hand Surg 2000; 25 A: 464-468. Reference 4: Omokawa S, Iida A, Fujitani R, Onishi T, Tanaka Y. Radiographic predictors of DRUJ instability with distal radius fractures. Jnl Wrist Surg 2014; 03: 2-6.

Table 1 Summary of Patient and Fracture Characteristics Control (n=324) Cases (n=22)

Age(years) 64±19 60±18

Gender Female 201 (62%) 14 (64%) Male 123 (38%) 8 (36%)

AO classification A3: 81 C1: 33 A3: 3 C2: 9 C2: 97 C3: 66 C3: 10 Ulnar styroid fracture 211 (65%) 18 (82%)

Control: patients without complete radioulnar ligament tear at fovea of ulnar head Cases: patients with complete radioulnar ligament at fovea of ulnar head

Table 2 Summary of Radiographic, Objective and Subjective outcomes

Gap distance at injury 4.9±3.2mm Gap distance at 1-y F.U. 1.3±0.9mm * DRUJ OA grade Grade 0: 22 Grade1: 0 Grade2: 0 Grade3: 0 DRUJ instability +/- +:1 -:21

% Flexion+Extension 87±19% % Supination+Pronation 93± 1% % GS 85±14%

Ulnar wrist pain (VAS) 1.1 Sense of instability +/- +:1 -:21 DASH 13±10 Cooney’s wrist score Excellent:20 Good:2

Abbreviations % Flexion+Extension, % Supination+Pronation %GS: Percentage of one of the injured wrist compared to the contralateral wrist * : statistically significant

♦ No relevant financial relationships to disclose

E-poster 90: Factors Influencing Infection Rates after Open Fractures of the Distal Radius

Category: Evaluation/Diagnosis, Treatment, Prognosis/Outcomes Keyword: Hand and Wrist, General Principles Level 4 Evidence

♦ Justin Zumsteg, MD ♦ Cesar S Molina, MD ♦ Donald H Lee, MD ♦ Nicholas Pappas, MD

Hypothesis: The purpose of this study is to determine which factors influence the rates of infection following open fractures of the distal radius. We hypothesize that earlier administration of antibiotics and earlier time to debridement will be associated with lower infection rates.

Methods: 125 patients with open distal radius fractures were reviewed. Of the 125 patients, 62 had at least 6-month follow up and were included in this study. The following variables were examined for each patient: time to receiving antibiotics, time to operative debridement, Gustilo-Anderson classification, type of antibiotic received, fixation characteristics and host characteristics such as age, diabetes, and tobacco use. Outcome parameters included the presence of deep infection and fracture union. Statistical analysis was performed using Fisher’s and chi-square tests.

Results: Based on the Gustilo-Anderson classification system, 27.4% (17/62) were type 1, 27.4% (17/62) were type 2, and 45.2% (28/62) were type 3 injuries. Of the 62 patients who had at least 6- month follow up, the overall rate of deep infection was 1.6% (1/62) and the rate of non-union was 7.4% (4/54). No type 1 or type 2 fractures developed either deep infection or non-union. The one deep infection occurred in a type 3 injury, which was successfully treated with debridement and removal of hardware. 15.4% (4/26) of the type 3 injuries developed a non- union, 2 of which were noted to have significant bone loss from the initial injury. Neither time to antibiotics nor time to debridement was associated with the development of deep infection or non-union.

Summary Points: - Open distal radius fractures have a relatively low rate of infection (1.6%). - No type 1 or 2 fracture developed deep infection or non-union. - Factors such as time to antibiotics and time to operative debridement were not associated with the development of either deep infection or non-union. - The “type” of fracture as outlined by the Gustilo-Anderson classification played the most substantial role in predicting both infection and non-union, which suggests that the severity of the initial injury as opposed to the initial management ultimately has the greatest influence on outcome.

References: Reference 1: Gustilo RB, Anderson JT. Prevention of infection in the treatment of one thousand and twenty-five open fractures of long bones: retrospective and prospective analyses. J Bone Joint Surg Am. 1976;58(4):453–458. Reference 2: Patzakis MJ, Wilkins J. Factors influencing infection rate in open fracture wounds. Clinical Orthopaedics and Related Research. 1989;(243):36–40. Reference 3: Singh J, Rambani R, Hashim Z, Raman R, Sharma HK. The relationship between time to surgical debridement and incidence of infection in grade III open fractures. Strategies Trauma Limb Reconstr. 2012;7(1):33–37. Reference 4: Freidrich PL. Die aseptische Versorgung frischer Wunden, unter Mittheilung von Thier-Versuchen uber die Auskeimungszeit von Infectionserregern in frischen Wunden. Archiv fur Klinsche Chirugie; 1898:288–310. Reference 5: Robson MC, Duke WF, Krizek TJ. Rapid bacterial screening in the treatment of civilian wounds. J Surg Res. 1973;14(5):426–430. Reference 6: Khatod M, Botte MJ, Hoyt DB, Meyer RS, Smith JM, Akeson WH. Outcomes in Open Tibia Fractures: Relationship between Delay in Treatment and Infection. J Trauma. 2003;55(5):949–954. Reference 7: Glueck DA, Charoglu CP, Lawton JN. Factors associated with infection following open distal radius fractures. Hand (N Y). 2009;4(3):330–334. Reference 8: Rozental TD, Beredjiklian PK, Steinberg DR, Bozentka DJ. Open fractures of the distal radius. J Hand Surg Am. 2002;27(1):77–85. Reference 9: Kurylo JC, Axelrad TW, Tornetta P, Jawa A. Open fractures of the distal radius: the effects of delayed debridement and immediate internal fixation on infection rates and the need for secondary procedures. J Hand Surg Am. 2011;36(7):1131–1134.

● Royalty: Biomet (Lee) ● Consulting Fee: Biomet (Lee) ● Speakers Bureau: Biomet (Lee)

♦ No relevant financial relationships to disclose E-poster 91: Predictors of cubitus varus deformity after operative treatment for displaced supracondylar humeral fractures in children

Category: Treatment Keyword: Elbow and Forearm Level 2 Evidence

♦ Takamasa Shimizu, MD,PhD ♦ Shohei Omokawa, MD,PhD ♦ Atsushi Yoshida, MD, PhD ♦ Osamu Kisanuki, MD, PhD ♦ Hiroshi Ono, MD, PhD ♦ Yasuhito Tanaka, MD/PhD

Hypothesis: To identify the most important determinants of cubitus varus deformity after manual reduction with percutaneous K-wire fixation for treatment of pediatric supracondylar humeral fractures, multivariate regression analysis was used to test the hypothesis that accurate anatomical reduction is required to prevent the deformity.

Methods: One hundred twenty-two patients (84 male and 40 female patients; 7 ± 2 years of age) with displaced supracondylar humeral fractures were evaluated at a minimum of 6 months after surgery. We examined 7 variables: 2 patient characteristics (gender and age), 3 fracture characteristics (type of fracture, ulnar displacement of distal fragment, and comminution of the medial cortex on initial anteroposterior (AP) radiographs), and 2 surgical variables (anatomical accuracy of reduction and postoperative redisplacement). Fracture type was classified according to the Wilkins modification of the Gartland classification system.1 Anatomical accuracy of reduction was evaluated by 2 radiographic parameters on immediately postoperative lateral radiographs: the anterior humeral line (AHL) and persistence of anterior spike of the proximal fragment. Baumann’s angle on immediately postoperative AP radiographs was used as an index to prevent cubitus varus deformity on behalf of the carrying angle (CA) (Figure 1). Univariate analyses followed by multivariate logistic regression analysis were conducted to identify the predictive variables of postoperative cubitus varus deformity.

Results: Cubitus varus deformity was defined as a deformity with CA of < 0º at final follow-up and was found in 23 patients. There were 55 type III fractures, 70 ulnar displacements of the distal fragment, and 31 comminuted fractures of the medial cortex. The AHL passed through the anterior third of the capitellum in 63 patients. Multivariate logistic regression analysis showed that the AHL, ulnar displacement of the distal fragment, and comminution of the medial cortex were independent predictors. The final regression model including these 3 variables accounted for approximately 85% of the variance in cubitus varus deformity (Table 1).

Summary Points: 1) Ulnar displacement of the distal fragment and comminution of the medial cortex on AP radiographs at the initial injury are important predictors and unhappy signs of postoperative cubitus varus deformity following the occurrence of displaced supracondylar humeral fractures in children. 2) The AHL is useful to predict cubitus varus deformity and indicates either extensional or rotational deformity. 3) Based on the current analysis, accurate reduction of the fracture site are keys to preventing cubitus varus deformity when manual reduction and percutaneous pinning are conducted to treat supracondylar humeral fractures in children.

References: Reference 1: Wilkins KE. Fractures and dislocations of the elbow region. In: Rockwood CA Jr, ed. Fractures in children. Philadelphia: JB Lippincott; 1984:363-575. Reference 2: Keats TE, Teeslink R, Diamond AE, Williams JH. Normal axial relationships of the major joints. Radiology 87:904-907. 1966 Reference 3: Anthony AS. Supracondylar Fractures of the Elbow in Children. In: Morrrey BF, ed. The elbow and its disorder. 4th ed. New York, NY: Saunders; 2009:206-223.

♦ No relevant financial relationships to disclose

E-poster 92: Long-Term Clinical Outcome of Radial Shortening on Kienbock’s Disease

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist, Diseases and Disorders Level 4 Evidence

♦ Ali Moradi, MD ♦ Amir Reza Kachooei, MD ♦ Mohammad H Ebrahimzadeh, MD

Hypothesis: Radius shortening, regardless of ulnar variance, is not an appropriate method in the management of Kienbock’s disease.

Methods: In a prospective study, we enrolled 16 skeletally mature patients (9 men and 7 women) with Kienbock’s disease who underwent radius shortening osteotomy between 2002 and 2012. The mean age of our patients was 30 (Range: 18 to 43) years old. According to Litchman staging, there were 7 wrists at stage II and 9 wrists at stage III. The data of grip strength, pain (VAS score), wrist range of motion, ulnar variance and the Lichtman stage were recorded before surgery and at the last follow-up visit. We evaluated overall wrist function using the Mayo Wrist Score and DASH score before surgery and at the last follow-up.

Results: The average of follow-up was 7 years (Rang from 5 to 9 years). Preoperative ulnar variance was negative for 8 patients, positive for 3 and neutral in the other 5. The mean post-operative ulnar variance was 1 millimeter positive. The VAS pain score, the mean arc of wrist flexion and extension, and grip strength improved significantly preoperatively compared to after recovery from surgery. The Lichtman stage was unchanged in 9 patients, one grade worse in 6 patients, and one grade better in one patient. The mean DASH and Mayo scores improved significantly from 38 and 29 to 13 and 77, respectively.

Summary Points: • Even with creating an ulnar positive wrist, radial shortening osteotomy improves the patients’ outcome. • Pain, range of motion and grip strength improved significantly after radial shortening osteotomy as well as DASH and Mayo scores. • Based on long-term results, radial shortening osteotomy is an alternative method of surgery.

References: Reference 1: Weiss AP, Weiland AJ, Moore JR, Wilgis EF.Radial shortening for Kienböck disease.J Bone Joint Surg Am. 1991 Mar;73(3):384-91.

Table: Comparing pre-operative grip power and rang to motion with post-operative measurements.

Pre-operative Post-operative P Value

Mean 2SD Mean 2SD

Range of Motion 67 16 74 19 0.04

Grip power 62 28 81 21 0.01

DASH score 38 16 13 8 0.001

Mayo Wrist Score 29 22 77 17 0.003

♦ No relevant financial relationships to disclose E-poster 93: Dynamic Control of Fingertip Forces After Pollicization

Category: Prognosis/Outcomes Keyword: Hand and Wrist, Congenital and Pediatric Problems Level 3 Evidence

♦ Nina R.Lightdale, MD ♦ Nicole M. Mueske, MS ♦ Jennifer Loiselle, OTR, MPH ♦ Jamie Berggren, OTR ♦ Francisco Valero-Cuevas, PhD ♦ Tishya A. L. Wren, PhD

Hypothesis: Pollicized hands will have deficits in the control of fingertip forces, with the thumb showing greater deficits than the first finger.

Methods: We evaluated 11 pollicized (4 bilateral, 3 unilateral) hands from 7 patients (age 10.7 ± 6.0 years, range 5-19) and 13 control hands from 7 healthy volunteers (age 11.0 ± 4.7 years, range 5-17) using a novel strength-dexterity (S-D) test [1]. Participants attempted to compress and hold an instrumented spring between the thumb and first (next most radial) finger to quantitatively assess the dynamic control of fingertip forces. Greater compression (measured using maximum force) indicates better control of fingertip forces since the spring becomes more unstable the more it is compressed. The thumb and first finger were also assessed individually by having each digit compress the spring with the other digit resting on a stable base. Retrospective chart and x- ray review provided clinical information. Differences among groups (pollicized vs. control) were compared using Student’s t-tests.

Results: The pollicized hands had significantly lower S-D forces in all test conditions (Table). The mean difference between the pollicized and control hands was larger for the thumb than for the first finger and was largest for both digits combined. The hands with the lowest S-D scores had a Blauth V classification. For combined function of both digits, S-D forces were higher with smaller first web angles (p=0.046).

Summary Points: • In pollicized hands, both the pollicized thumb and next most radial finger have deficits in the control of fingertip forces in mid- to long-term follow-up. • The pollicized thumb has greater deficits than the first finger. • Children with more involved radial longitudinal deficiency and wider first web space have significantly decreased dexterity after pollicization.

References: Reference 1: Valero-Cuevas, FJ, Smaby, N, Venkadesan, M, Peterson, M, Wright, T (2003). The strength-dexterity test as a measure of dynamic pinch performance. Journal of Biomechanics, 36(2): 265-270.

♦ No relevant financial relationships to disclose

E-poster 94: Preoperative EKG Testing in Non-syndromic Children with Hand Syndactyly

Category: Evaluation/Diagnosis, Treatment Keyword: Hand and Wrist, Congenital and Pediatric Problems, Diseases and Disorders, Practice Management Level 4 Evidence

♦ Laura CNuzzi, BA ♦ Eliza B Lewine, BS ♦ Donald S. Bae, MD ♦ Amir Taghinia, MD ♦ Peter M Waters, MD ♦ Brian I Labow, MD

Hypothesis: The risk of sudden cardiac events in patients with Timothy syndrome, a rare and fatal condition characterized by hand syndactyly and a prolonged QT interval on EKG,(1,2) has led to recommendations for preoperative EKG’s for all syndactyly patients undergoing surgical treatment.(1,3) We hypothesize that the rarity and presentation of this disorder, along with the additional charges associated with testing, do not support mandates for EKG screening in all healthy children referred for surgery.

Methods: This retrospective study reviewed the records of syndactyly patients treated by a hand surgeon at our institution from 2007-2013. Non-syndromic, healthy children with hand syndactyly referred for surgery were included. As per our institutional policy, all underwent preoperative screening EKG’s. Medical records were reviewed for demographics, clinical presentation, EKG results, and operative findings. Median age at the time of EKG and surgery were calculated. Frequency distributions were also calculated for: gender, side affected, EKG result, and clinical finding. Mean patient charge for EKG was calculated.

Results: One hundred twenty-eight non-syndromic syndactyly patients were identified. The majority of patients were male (71.9%), and the mean ages at time of EKG and syndactyly release were roughly 1 year. Most patients (93.8%) had normal EKG results, with only 1 patient receiving a diagnosis of long QT. No patient met the QT threshold for Timothy syndrome, and all patients were cleared for surgery. The mean patient charge for EKG testing was roughly $180.00.

Summary Points: • In an effort to improve patient safety, routine preoperative EKG testing has been advocated by some for children undergoing syndactyly release to rule out Timothy syndrome.(1,3) Timothy syndrome is rare and lethal, with the majority of known cases diagnosed during the first few weeks to months of life,(1) well before the typical age of syndactyly release.(4) • Retrospective analysis of our institutional experience failed to yield a single instance of Timothy syndrome in syndactyly release patients over a 6 year period. • Although direct charges for screening EKG tests are relatively low, additional costs due to false positive EKG findings, and physician, nursing, administrative, and parent time should also be considered. • In an era of increasing mandates to improve patient safety yet decrease health care costs, insufficient evidence exists to support routine EKG testing in children referred for syndactyly release.

References: Reference 1: Marks ML, Whisler SL, Clericuzio C, Keating M. A new form of long QT syndrome associated with syndactyly. Journal of the American College of Cardiology, 1995;25(1):59-64. Reference 2: Splawski I, Timothy K, Sharpe L, Decher N, Kumar P, Bloise R, et al. Cav1.2 calcium channel dysfunction causes a multisystem disorder including arrhythmia and autism. Cell, 2004;119(1):19-31. Reference 3: Seslar SP, Zimetbaun PJ, Berul CI, Josephson. Clinical features of congenital long QT syndrome. In: Basow DS, editor, UpToDate, Waltham, MA, 2013. Reference 4: Dao KD, Shin AY, Billings A, Oberg KC, Wood VE. Surgical treatment of congenital syndactyly of the hand. J Am Acad Orthop Surg, 2004;12(1):39-48.

♦ No relevant financial relationships to disclose

E-poster 95: Clinical Outcomes of Forearm Fasciectomy for Treatment of Chronic Exertional Forearm Compartment Syndrome at Minimum One Year Follow-up

Category: Treatment, Prognosis/Outcomes Keyword: Elbow and Forearm, Shoulder and Arm Level 4 Evidence

♦ Benjamin RWiseley, BS

Hypothesis: Chronic exertional compartment syndrome (CECS) of the forearm is an uncommon condition characterized by claudication of the forearm flexors and extensors brought on by repetitive use. The gold standard treatment for forearm CECS is surgical compartment release. The purpose of this retrospective case series is to evaluate the long-term outcomes of forearm fasciectomy for treatment of CECS.

Methods: IRB approval was obtained, and a retrospective case series was performed by evaluating participants who had undergone forearm fasciectomy as a treatment for CECS. Participants were identified and asked to complete a phone questionnaire and consent to a medical record review. The phone questionnaire used the QuickDASH tool to assess current forearm functionality and patient satisfaction. Data collected from the medical records included patient demographics, symptoms, diagnosis, outcomes, and complications.

Results: Thirteen patients (9 females, 4 males) who had surgical compartment release were identified over a 10 year period, 12 of which (9 females, 3 males) agreed to participate in the study. The mean age at the time of surgery was 22.4(+/-6.8) years and the average ICP measurement of the surgical arm was 40.9(+/-18.9) mmHg (normal = 10 mmHg). Six patients had bilateral releases and 6 had unilateral releases, 18 fasciectomies total. The average follow-up time was 88.7(+/- 31.2) months and the average QDASH score was 14.4(+/-13.4). Ten out of 12 patients stated they were “satisfied” with their outcome and the average estimate of current forearm function based on their previous level was 83.9%, with 4 out of 11 (36.4%) reporting a return to 100%. Complications included 4 patients who required a second release. In addition, patients also reported hypertrophic scarring, hematomas, and adhesions. Four participants reported lower limb symptoms of CECS.

Summary: -Forearm fasciectomy appears to be an effective treatment for forearm CECS as 10 out of 12 patients were satisfied with their outcome and able to engage in their previous activities. -The relatively low average QDASH score of 14.4 suggests very little forearm dysfunction after the surgery -This condition appears to be more prevalent in females as 9 out 13 potential participants were female. -There was a high incidence of bilateral CECS represented by this study population. -Four out of 12 participants reported coincidental lower extremity CECS symptoms, suggesting a physiologic predisposition to CECS.

References: Reference 1: Croutzet P, Chassat R, Masmejean EH. Mini-invasive surgery for chronic exertional compartment syndrome of the forearm: a new technique. Tech Hand Up Extrem Surg. 2009 Sep;13(3):137-40. PubMed PMID: 19730042.

♦ No relevant financial relationships to disclose

E-poster 96: Treatment of pediatric torus fractures using standardized clinical assessment and management plans (SCAMPs)

Category: Evaluation/Diagnosis, Treatment, Prognosis/Outcomes, Billing/Coding Keyword: Elbow and Forearm, Practice Management Level 2 Evidence

♦ Gaurav Luther, MD ♦ Patricia E. Miller, MS ♦ Peter M. Waters, MD ♦ Donald S. Bae, MD

Hypothesis: Standardized clinical assessment and management plans (SCAMPs) are a novel quality improvement initiative shown to improve patient care, diminish practice variation, and reduce unnecessary resource utilization. We have recently implemented a SCAMP for the closed treatment of pediatric torus fractures. The purpose of this study is to analyze the effect of SCAMPs on resource utilization, practice variability and overall cost of care. Hypothesis SCAMPs implementation will reduce resource utilization, practice variability and overall cost of care in pediatric torus fractures

Methods: This study was a review of prospectively collected data on 273 patients with torus fractures. The pre-SCAMP cohort included 116 subjects treated from 2006-2008. The SCAMP cohort included 157 subjects from 2010-2012. The pre-SCAMP cohort was treated according to the judgment of a fellowship-trained pediatric orthopaedic surgeon. The SCAMP cohort was treated with a standardized algorithm including radiographs and splint application at initial presentation, with a single clinical follow-up visit 3 weeks after injury. Any deviations from the SCAMP were recorded. Patient demographics including age, gender and time to presentation were analyzed to verify comparability between cohorts. Follow-up data including number of clinic visits, x-rays and variability in physician practice was recorded. A modified costing analysis was conducted using time-derived activity based costing (TDABC). Outcomes were compared between cohorts using Poisson regression analysis. Incident rate ratios (IRR) with 95% confidence limits were estimated.

Results: No differences in clinical results were observed between the pre-SCAMP and SCAMP cohorts, and all patients demonstrated return to baseline activity at their final follow-up visit. Patient age, gender and time from injury to presentation were comparable across groups (Table 1). Poisson regression determined that the pre-SCAMP cohort had 1.4 times as many clinic visits (IRR=1.4; 95% CI=1.2-1.6; p<0.001) and 3.5 times as many x-rays as the SCAMP cohort (IRR=3.5; 95% CI=2.9-4.2; p<0.001) (Table 2). In addition the pre-SCAMP cohort had 2.4 times as many x-rays per clinic visit as the post-SCAMP cohort (IRR=2.4; 95% CI=1.9-3.0); p<0.001). Physician practice variation was significantly reduced within the SCAMP cohort (p<0.001). Furthermore, TDABC analysis demonstrated that SCAMPs implementation resulted in a 54% reduction in the overall cost of care.

Summary Points: - In pediatric torus fractures, SCAMPs implementation significantly reduces physician practice variability - The SCAMP cohort utilized 1.4x fewer clinic visits and 3.5x fewer radiographs than the pre- SCAMP cohort - SCAMPs implementation results in a cost savings of over 50% of the overall cost of care - Level of Evidence: 2

References: Reference 1: Bae, D. S.: Pediatric distal radius and forearm fractures. J Hand Surg Am, 33(10): 1911-23, 2008 Reference 2: Davidson JS, Brown DJ et al. Simple treatment for torus fractures of the distal radius, JBJS. 1173-1175. 2001 Reference 3: Solan MC, Rees R et al. Current management of torus fractures of the distal radius. Injury 503-505. 2002. Reference 4: Kaplan, R. S., and Porter, M. E.: How to solve the cost crisis in health care. Harv Bus Rev, 89(9): 46-52, 54, 56-61 passim, 2011. Reference 5: Rathod RH, Farias M. A novel approach to gathering and acting on relevant clinical information: SCAMPs. Congenit Heart Dis. 2010;5:343-353 Reference 6: Friedman KG, Kane DA. Management of pediatric chest pain using a standardized assessment and management plan. Pediatrics. 2011;128:239-245 Reference 7: Brinker, M. R.; Pierce, P.; and Siegel, G.: Development of a method to analyze orthopaedic practice expenses. Clin Orthop Relat Res, (372): 302-13, 2000 Reference 8: Wennberg, J.E., Practice variation: implications for our health care system. Manag Care, 2004. 13(9 Suppl): p. 3-7.

♦ No relevant financial relationships to disclose

E-poster 97: Association between range of motion and patient- perceived outcome of the wrist after distal radius fractures

Category: Therapy/Rehabilitation Keyword: Hand and Wrist Level 4 Evidence

♦ Yoshihiro Dohi, PhD ♦ Kenji Kasubuchi, OT ♦ Hiroshi Ono, MD, PhD ♦ Shohei Omokawa, MD,PhD ♦ Yasuhito Tanaka, MD/PhD

Hypothesis: Some author reported that grip strength was associated with patient-perceived outcome after distal radius fractures1),2). But association between range of motion and patient-perceived outcome is not so clear now. Though the dart-throwing motion is functional and practical movement from radial extension to ulnar flection of wrist, we hypothesized that goniometric measurement for the dart-throwing motion might demonstrate the association between range of motion and patient-perceived outcome.

Methods: Twenty-six cases of the distal radius fractures treated with a volar locking plate were prospectively enrolled in this study. The patients included seven men and 19 women with an average age of 66 years old. Five patients had AO type A fracture, and two patients had AO type B fracture, 19 had AO type C fracture. Average period after surgery was 26 weeks. The dart- throwing motion (DTM) was defined as a movement from radiodorsal to ulnopalmar and oblique to the sagittal plane,3),4) and the arc of the DTM plane was measured using a custom-made goniometer (figure1) at final follow up. The reverse dart-throwing motion (RDTM) that was a orthogonal movement to DTM from ulnar-extension to radial flexion was measured as well. The flexion-extension motion (FEM) and radio-ulnar deviation (RUD), external-internal rotation (EIR) was also measured with a standard goniometer and the disabilities of the arm, shoulder, and hand outcome (DASH) score was measured at the same time. The correlations between each of the goniometric parameters and the DASH score were analyzed by Pearson's correlation. The goniometric parameters of were selected for the final logistic regression model using the SPSS stepwise procedure. The contributions of each of the goniometric parameters with respect to the DASH score were analyzed by partial regression coefficient in a multiple regression model (SPSS, version12).

Results: All of the radiographic parameters were correlated with the DASH score (p<0.05). But the DTM and RDTM were selected by stepwise procedure. The partial regression coefficients of DTM and RDTM with respect to DASH score were -0.556 (p<0.01) and -0.392 (p=0.01), respectively. The multiple coefficient of determination (R2) was 77.4%

Summary Points: According to the multiple regression analysis, the increased the DTM and RDTM were associated with the patient-perceived outcome and the DTM was more associated than RDTM. It is important to pay attention to the DTM during postoperative hand therapy after the distal radius fractures

References: Reference 1: Wilcke MK, Abbaszadegan H, Adolphson PY. Patient-perceived Outcome after Displaced Distal Radius Fractures. J Hand Ther 10-11: 290-298, 2007 Reference 2: Karnezis IA, Fragkiadalcis EG. Association between objective clinical variables and patient-rated disability of the wrist. J Bone Joint Surg 84-B: 967-970, 2002 Reference 3: Moritomo H, Murase T, Goto A, Oka K, Sugamoto K, Yoshikawa H. In vivo three- dimensional kinematics of the midcarpal joint of the wrist. J Bone Joint Surg Am. 2006 Mar; 88: 611-21 Reference 4: Crisco JJ, Coburn JC, Moore DC, Akelman E, Weiss AP, Wolfe SW. In vivo radiocarpal kinematics and the dart thrower's motion. J Bone Joint Surg Am. 2005 Dec; 87: 2729-40.

♦ No relevant financial relationships to disclose

E-poster 98: Biomechanical analysis of scapholunate ligament repair techniques

Category: Basic Science Keyword: Hand and Wrist N/A - Not a clinical study

♦ Eugene Tek, MD, PhD ♦ Kathleen Meyers, MS ♦ Mike T Wei, BS ♦ Krystle A Hearns, MA ♦ Michelle Gerwin Carlson, MD

Hypothesis: The treatment of acute tears of the scapholunate ligament relies on anatomical reduction of the scapholunate complex and primary repair of the scapholunate ligament disruption. Successful repair is paramount as failure can lead to carpal instability and later degenerative arthritis. Several repair techniques have been described, however there is no data in the current literature that has compared the biomechanical properties of each repair. The aim of this study was to evaluate the biomechanical properties of 3 different scapholunate repair techniques.

Methods: The scaphoid and lunate with the intact scapholunate ligament was exposed through a dorsal approach. The scapholunate ligament was sharply dissected off its lunate insertion and subsequently repaired using one of 3 different fixation techniques – 1) 2 single loaded suture anchors, 2) 2 double loaded suture anchors and 3) 2 transosseous sutures. Following repair, the entire scapholunate complex was harvested and tensile testing of all specimens was performed using servohydraulic material testing and data acquisition software. A distractive load of 10mm/min (0.17mm/sec) was applied until the specimens reached ultimate failure. A second set of specimens underwent cyclic testing at 1 Hz from 3N-25N for 300 cycles. This represents 10% to 80% of ultimate failure load for the weakest failure group. Gap formation was measured.

Results: In all but 1 specimen, the mode of failure was pullout of the sutures through the substance of the scapholunate ligament. Repairs using double loaded suture anchors demonstrated a significantly higher mean ultimate load to failure compared to single loaded suture anchors (90.9 ± 27.3 vs. 35.2 ± 9.5, p < 0.001) and transosseous suture repairs ( 90.9 ± 27.3 vs. 60.3 ± 15.1, p =0.03). Transosseous suture repairs demonstrated a higher mean ultimate load to failure when compared to single loaded suture repairs (60.3 ± 15 vs. 35.2 ± 9.5, p = 0.03). (Figure 1) On cyclic loading, the average gap for the tranosseous suture repair group at 300 cycles was three times larger than the average gap for the single and double loaded repairs. However, due to specimen variability, no difference statistical difference was found. (Figure 2)

Summary points: • Primary scapholunate ligament repairs using double loaded suture anchors demonstrated significantly higher biomechanical strength when compared to single loaded suture anchor and transosseous suture repairs. • Transosseous suture repair demonstrated the greatest gap formation on cyclic loading. • No difference was seen between single and double loaded repairs on cyclic loading.

Average Load to Failure 140

120

100

80

Load(N) 60

40

20

0 Single Loaded Anchor Double Loaded Anchor Transosseous

Average Gap Formation 25N 4

3.5

3

2.5

2 singleloaded

1.5 doubleloaded trans

1 Normalized Normalized gap(mm) 0.5

0 0 10 25 50 100 150 200 300 -0.5 Cycle #

♦ No relevant financial relationships to disclose

E-poster 99: Effects of Patient Positioning on Displacement of Midshaft Clavicle Fractures

Category: Treatment Keyword: Shoulder and Arm Level 4 Evidence

♦ Carissa Meyer, MD ♦ Awais Malik, BS ● Joshua Abzug, MD

Hypothesis: Midshaft clavicle fractures account for 2.5-10% of all adult fractures and 80% of clavicle fractures1, 2, 3. Recent studies of these fractures show a non-union rate up to 15%4,5. McKee et al have shown improved healing for fractures with 100% displacement or >2cm overlap with operative treatment6. We theorize that dynamic displacement of fracture fragments during the healing process may also play a role in the non-union rate. The objective of this study was to determine the effects of positional change on displacement of midshaft clavicle fractures. We hypothesized that change in position will increase both “vertical” (cephalad-caudad) and “horizontal” (fracture overlap) displacements of midshaft clavicle fractures.

Methods: A retrospective review of 81 patients with displaced midshaft clavicle fractures was performed. The vertical and horizontal displacements of the fractures were measured in various patient postures using radiographic software tools. Initial measurements were performed on supine chest radiographs and the measurements were subsequently repeated on semi-upright and/or upright chest radiographs. Statistical analysis was performed utilizing paired t-tests. Results: Mean vertical displacement increased from 6.2 mm to 14.3 mm as patients changed position from supine to upright/semi-upright, respectively (p0.05). There was a 5.3-fold increase in the number of patients who met the potential operative criteria (shortening of =20 mm) with change in position from supine to semi-upright or upright.

Summary Points: - Patient positioning alters displacement of midshaft clavicle fractures in vertical direction but has no significant effect on horizontal displacement. - Patients may be considered operative candidates based on displacement noted on upright films whereas they may be considered non-operative candidates if the supine film is evaluated.

References: Reference 1: Robinson CM. Fractures of the clavicle in the adult. Epidemiology and classification. J Bone Joint Surg Br. 1998;80:476-84. Reference 2: Postacchini F; Gumina S; De Santis P; Albo F. Epidemiology of clavicle fractures. J Shoulder Elbow Surg. 2002;11:452-6. Reference 3: Neer CS. Non-union of the clavicle. JAMA. 1960;172:1006-11 Reference 4: Hill JM, McGuire MH, Crosby LA. Closed treatment of displaced middle-third fractures of the clavicle gives poor results. J Bone Joint Surg Br. 1997;79:537-9. Reference 5: Zlowodski M, Zelle BA, Cole PA, Jeray K, McKee MD. Treatment of acute midshaft clavicle fractures: systematic review of 2144 fractures: on behalf of the Evidence-Based Orthopaedic Trauma Working Group. J Orthop Trauma. 2005; 19:504-7. Reference 6: McKee MD, Pedersen EM, Jones C, Stephen DJ, Kreder HJ, Schemitsch EH, Wild LM, Potter J. Deficits following nonoperative treatment of displaced midshaft clavicular fractures. J Bone Joint Surg Am. 2006;88:35-40.

● Royalty: Springer (Abzug) ● Consulting Fee: Axogen (Abzug)

♦ No relevant financial relationships to disclose

E-poster 100: Fibrotic Gene Expression in Diabetic Patients with Carpal Tunnel Syndrome

Category: Basic Science Keyword: Hand and Wrist, Diseases and Disorders Level 3 Evidence

♦ Anne Gingery, PhD ♦ Tai-Hua Yang, MD ♦ Kai-Nan An, PhD ♦ Chunfeng Zhao, MD ♦ Peter Amadio, MD

Hypothesis: Diabetic carpal tunnel syndrome (CTS) patients have increased fibrotic gene expression in subsynovial connective tissue (SSCT) as compared to non-diabetic CTS patients and non-diabetic, non-CTS subject controls.

Methods: Following approval by our IRB, SSCT biopsy specimens were taken from the carpal tunnel of patients undergoing carpal tunnel release in both diabetic(n=3) and non-diabetic patients (n=5). As a non-diabetic control, cadaver SSCT (n=5) was harvested within 6 hours of death. Tissue was flash frozen, RNA isolated, cDNA synthesized and subsequently analyzed using RT2 Profiler PCR Human Fibrosis Arrays. Statistical significance was determined by 2-tailed Student's T-test at p< 0.05.

Results: Scatterplot comparisons (Figure 1) of the SSCT from diabetic CTS patients versus control tissue (A) and diabetic patients versus non-diabetic patients (B) indicate fibrotic gene expression. Outside lines denote two fold gene expression differences. In both analyses fibrotic gene expression was highly upregulated in tissue from diabetic patients. Figure 2 further illustrates significantly increased expression of specific genes related to multiple fibrotic pathways including: extracellular matrix (ECM), TGF-beta? signaling, fibrosis mediators and ECM regulating enzymes.

Summary: • Fibrotic gene expression is significantly and substantially increased in diabetic patients with CTS compared to non-diabetic patients with CTS. • Fibrotic gene expression is significantly and substantially increased in diabetic patients with CTS compared individuals with neither diabetes or CTS. • Multiple fibrotic pathways are significantly upregulated in diabetic patients with CTS. • Future work continues to evaluate the expression of fibrotic genes in CTS patient with diabetes including the effect of specific diabetic treatment regimens. • The underlying fibrosis in CTS patients appears to pose a special case for diabetic patients in whom fibrosis is exacerbated and may further complicate treatment.

References: Reference 1: Ettema, AM, Amadio, PC, Zhao, C, Wold, LE, An, KN. A histological and immunohistochemical study of the subsynovial connective tissue in idiopathic carpal tunnel syndrome. J Bone Joint Surg Am, 2004. 86-A(7): 1458-66. Reference 2: Chikenji, T, Gingery, A, Zhao, C, Passe, SM, Ozasa, Y, Larson, D, An, KN, Amadio, PC. Transforming growth factor-beta (TGF-beta) expression is increased in the subsynovial connective tissues of patients with idiopathic carpal tunnel syndrome. J Orthop Res 2014, 1: 116- 22. Reference 3: Perkins, B.A., D. Olaleye, and V. Bril, Carpal tunnel syndrome in patients with diabetic polyneuropathy. Diabetes Care, 2002. 25(3): p. 565-9

♦ No relevant financial relationships to disclose

E-poster 101: Surgical Setting and Cost Effectiveness in Trigger Finger Release

Category: Treatment, Prognosis/Outcomes, Billing/Coding Keyword: Hand and Wrist Level 3 Evidence

♦ Elliot P Robinson, MD ● R. Glenn Gaston, MD

Hypothesis: Office-based procedure (OPR) room A1 pulley release offers considerable cost savings compared to stand-alone surgery center (SASC) and hospital ambulatory surgery centers (HASC), without any increased risk to the patient. Furthermore, current reimbursement schemes do not encourage the adoption of cost-effective practices.

Methods: Billing records in one academic private practice were queried to generate a consecutive list of patients undergoing A1 release (Code 26055) between January 2010 and May 2012. 50 patients from each setting were chosen (HASC, SASC, or OPR). Releases in the OPR were typically performed under field sterility with local anesthesia with epinephrine, while releases in the surgical centers were performed with general sedation, local anesthesia, tourniquet and full prep and drape. Clinical data regarding surgical site, concurrent procedures, and complications were extracted from the medical record. Data regarding payer source, billing and collections were obtained from business office records.

Results: 50 patients had one or multiple trigger finger releases in each of the three surgical settings for a total of 150 patients with a grand total of 197 releases. There were 6 complications (4%) evenly distributed among centers. One infection required I&D in the OR, while the remaining site reactions or infections resolved with observation or PO antibiotics. There were no re-operations for persistent triggering. Total paid cost of care varied based upon the setting. OPR costs ranged from $463 to $669. SASC ranged from $1528 to $2292. The highest cost was for the HASC at $2979. Release performed in the OPR instead of SASC saved payers between $859 (56%) and $1829 (80%). Even greater cost savings were seen comparing the OPR with the HASC, with a difference of $2515 (84%). The mean physician reimbursement for code was $609. When performed at the OPR, the cost of supplies and assistant time must be subtracted. This was estimated at $90, which translates to a 15% decrease in reimbursement. Summary Points: 1.A1 release can be safely performed under field sterility with local anesthesia with epinephrine in an OPR. 2.OPR A1 release provides significant cost-savings (56-84%) compared to SASC and HASC. 3.Payer reimbursement schemes lead to limited surgeon incentive to decrease the use of standard OR resources, and therefore higher costs.

References: Reference 1: Kerrigan, C. L., & Stanwix, M. G. (2007). Using Evidence to Minimize the Cost of Trigger Finger Care. JHS, 34(6), 997–1005. Reference 2: Mather, R. C., Wysocki, R. W., Aldridge, J. M., Pietrobon, R., & Nunley, J. A. (2011). Effect of Facility on the Operative Costs of Distal Radius Fractures. JHU, 36(7), 1142–1148. Reference 3: LeBlanc, M. R., Lalonde, D. H., Thoma, A., Bell, M., Wells, N., Allen, M., Chang, P., et al. (2010). Is main operating room sterility really necessary in carpal tunnel surgery? A multicenter prospective study of minor procedure room field sterility surgery. HAND, 6(1), 60– 63. Reference 4: LeBlanc, M. R., Lalonde, J., & Lalonde, D. H. (2007). A Detailed Cost and Efficiency Analysis of Performing Carpal Tunnel Surgery in the Main Operating Room versus the Ambulatory Setting in Canada. HAND, 2(4), 173–178. Reference 5: Amadio, P. C. (2012). What’s New in Hand Surgery. The Journal of bone and joint surgery American volume, 94(6), 569.

● Royalty: Biomet (Gaston) ● Consulting Fee: Biomet (Gaston) ● Speakers Bureau: Auxillium, Biomet (Gaston)

♦ No relevant financial relationships to disclose

E-poster 102: Correction of Diaphyseal Malunion of the Forearm, using 3D Planning and Patient Specific Surgical Guides and Implants

Category: Treatment, Surgical Technique Keyword: Elbow and Forearm Level 4 Evidence

♦ Bianca Impelmans, MD ♦ Jan Vermeire, MD ♦ Frederik Verstreken, MD

Hypothesis: Preoperative 3D computer planning of the surgical correction of both bone forearm diaphyseal malunions, and the fabrication of patient specific surgical guides and implants for fixation, allows precise reconstruction of anatomy and restoration of function.

Methods: Five patients with a symptomatic diaphyseal malunion of both bones of the forearm were included in a prospective study. All had a corrective osteotomy of both radius and ulna, using a new technique. With computer software, CT-scan data of both forearms are transformed into virtual 3D objects and the corrective osteotomies are precisely planned, using the mirror image of the non- affected site as a template. Based on this planning, patient specific drill and saw guides are designed and manufactured by 3D printing. In addition, patient specific titanium fixation plates are designed. These plates exactly match the contour of the corrected bone, and facilitate reduction and fixation of the bone fragments in the planned position. The average age at the time of surgery was 13 years (7-17 years). Corrective osteotomies were performed from 7 months to 9 years after the initial injury.

Results: All patients were evaluated postoperatively and the mean follow-up time was 13 months (9-24 months). The visual analogue scale for pain improved from 3.2 to 0.7. Range of forearm rotation was the most important functional problem preoperatively and improved significantly following osteotomy: pronation from 68° to 85° and supination from 47° to 83°. Grip strength improved non significantly from 21,5 kg to 22,5 kg. All osteotomies united uneventfully at an average time of 13 weeks (6-24 weeks) precisely in the pre-planned position. All patients and their parents were very satisfied and would have the procedure again.

Summary Points: -3D computer software allows planning of the correction of a malunion of both bones of the forearm -Patient specific surgical guides and fixation implants can be designed, based on this planning -The use of these guides and implants allows precise restoration of anatomy and forearm function -3D printed titanium implants have mechanical properties that allow fixation and healing of a forearm osteotomy

● Consulting Fee: Medartis (Verstreken) ● Contracted Research: Biomet, Auxilium (Verstreken)

♦ No relevant financial relationships to disclose E-poster 103: Vascularized Scapholunate Fusion in Scapholunate Instability

Category: Surgical Technique Keyword: Hand and Wrist N/A - Not a clinical study

♦ Richard Bernstein, MD

Hypothesis: Treatment of scapholunate instability remains a challenge for Hand Surgeons. The plethora of different procedures, suggests that the answer has not been found. Authors have suggested many soft tissue procedures as well as limited intracarpal fusions. Because the injury involves the scapholunate intraosseous ligament, if one chose the fusion option, a direct scapholunate fusion would seem the obvious choice, however the nonunion rate for this direct fusion has been high1. Rosenwaser2 published results of a pseudo fusion with the RASL procedure with good results; the current proposal would be a procedure to obtain a full fusion. Over the last several years, vascularized bone grafting for proximal row carpal problems has become popular. Zaidemberg3 and subsequently Bishop4 have described the technique of harvesting the 1,2 ICSRA for disorders of the proximal carpal row. This study investigates the applicability of this technique to obtain a scapholunate fusion.

Methods: Utilizing five fresh cadaver arms, the approach of Bishop4 to a scaphoid nonunion was utilized. The SL interval was developed, decorticated and had a trough fashioned with osteotomes. The 1,2 ICSRA was harvested, impacted, and the fusion was secured using a cannulated standard Accutrak screw. The graft size averaged 13.5mm the most common screw size was 17.5 mm, and stable fixation was accomplished. There was no kinking and good length on the pedicle.

Summary: Having demonstrated the feasibility in a cadaver model, the next investigative step will be a clinical trial to investigate the fusion rate of a vascularized bone graft augmentation of a scapholunate fusion.

References: Reference 1: Linscheid, RL Ann Chir Main 3: 323-330, 1984 Reference 2: Rosenwasser, et. Al. Tech Hand Up Extrem Surg. 1997 Dec;1(4):263-72 Reference 3: : Zaidemberg, J Hand Surg [Am]. 1991 16A 474-478 Reference 4: Steinman, Bishop, Berger, J Hand Surg [Am]. 2002;27(3):391-401

♦ No relevant financial relationships to disclose E-poster 104: Ultrastructure of the Radial Head

Category: Anatomy, Basic Science Keyword: Elbow and Forearm N/A - Not a clinical study

♦ Aidin Masoudi, MD ♦ Brian D Snyder, MD, PhD ♦ Susanne M Roberts, MD ♦ Brandon E Earp, MD ♦ George S M. Dyer, MD

Hypothesis: Satisfactory purchase of hardware used to stabilize radial head fractures depends on the “quality” of the bone, which is determined by the density and microstructural anatomy of the proximal radial metaphysis. We hypothesized that the microstructural anatomy of the proximal radius is different between the medial and lateral sides, which accounts for differences in biomechanical performance and can be applied to optimize fracture fixation.

Methods: Twenty four radial heads were harvested from fresh frozen human cadavers with the mean age of 60±19 years (Table 1) and hydrated in an antimicrobial-antifungal-antiprotease solution of 400 ± 20 mOsm/L (i.e. normal osmolality of synovial joint). To enhance visualization of the articular cartilage using micro-computed tomography (µCT) imaging, the specimens were allowed to equilibrate in the anionic, iodinated contrast agent Hexabrix® (320 mgl/mL) for 48 hours for passive diffusion. Serial transaxial µCT images of the proximal radius (Scanco Medical AG, Brüttisellen, Switzerland) were obtained and 3D reconstruction performed by ImageJ software[1] with BoneJ plugin[2] for quantitative morphological analysis. Defining the radial tuberosity as a landmark for the medial side, each 3D image was divided into a medial and lateral half. One trabecular bone cube comprised of 2,395,316 voxels was fitted in the nearest space to the cortical bone from each side and trabecular morphology measured. The thickness of the cartilage at the level of the sampled bone cube was also measured. (Figure 1)

Results: The cartilage thickness, relative trabecular bone fraction (BV/TV), mean trabecular bone thickness (TbTh) and mean inter-trabecular pore space (TbSp) were significantly different between the medial side and lateral side (p<0.0001), where the trabecular bone volume fraction, trabecular thickness and cartilage thickness were all greater medially than laterally and correspondingly the pore space was higher on the lateral side (Table 2, Chart 1-3) The trabeculae comprising the medial side were plate-like whereas the trabeculae comprising the lateral side were rod-like. Summary Points: Our data suggests that the microstructural anatomy of the bone forming the radial head is adapted to accommodate principally tensile forces on the lateral side and compressive forces on the medial side. Therefore it is important to consider these trabecular bone patterns when fixating the proximal radius, taking advantage of the more compact, higher density trabecular bone present medially.

References: Reference 1: Rasband WS. ImageJ, U.S. National Institutes of Health, Bethesda, Maryland, USA, imagej.nih.gov/ij/, 1997—2012. Reference 2: Doube M, Klosowski MM, Arganda-Carreras I, Cordeliéres F, Dougherty RP, Jackson J, Schmid B, Hutchinson JR, Shefelbine SJ. (2010) BoneJ: free and extensible bone image analysis in ImageJ. Bone 47:1076-9. doi: 10.1016/j.bone.2010.08.023

♦ No relevant financial relationships to disclose

E-poster 105: Recovery from a Distal Radial Fracture in Women over fifty; Implications for return to work

Category: Treatment, Therapy/Rehabilitation, Prognosis/Outcomes Keyword: Hand and Wrist Level 2 Evidence

♦ Geoffrey H.F. Johnston, MD

Hypothesis: Employers assume that recovery after a distal radial fracture should be complete soon after cast removal and patients are often frustrated that they cannot reasonably meet these expectations. Is time after fracture an acceptable metric of readiness to return to the workplace?

Methods: Orthopaedic surgeons and Emergency Room physicians who initiated treatment of distal radial fractures (by either closed or open means), then referred their patients to the author for ongoing management. From this single practice setting 893 adult women have been treated and followed prospectively in the last five years. Of these women 674 were 50 years or more old, and of these, 616 had isolated displaced distal radial fractures, 511 of which were treated non- operatively, and 105 surgically. In the 50-65 year old group there were 297 women, 230 of whom were treated non-operatively. Below elbow casting was for no more than 6 weeks in duration. At the first clinic visit, at 6 and 9 weeks post fracture the patients were coached on time-specific exercise protocols. At 9 and 12 weeks, and at 6 and 12 months post fracture patients completed a PRWE, and grip strengths were recorded, and expressed as a ratio of the opposite limb measurements.

Results: In 616 women fifty years and older, in the non-operative (and operative) groups respectively, the average PRWE score and grip strength ratio at 9 and 12 weeks, and at 6 and 12 months were 60 and .28 (66 and .35), 43 and .42 (51 and .49), 28 and .61 (36 and .63) and 20 and .79 (32 and .75). In the 50-65 years old group the comparable findings were 64 and .27 (69 and .37), 47 and .42 (55 and .48), 29 and .65 (43 and .64), and 19 and .81 (41 and .71), respectively.

Summary Points: In 616 women fifty years and older with isolated closed distal radial fractures, the resultant patient rated wrist evaluations and grip strengths at 9 and 12 weeks, and at 6 and 12 months post fracture were similar in both the non-operative and surgical groups, as well as in the 50-65 year old subset, and reflected that recovery was far from complete at nine and even twelve weeks post injury, and remained incomplete as far out as one year post fracture. More sophisticated metrics should be considered in determining the time for return to work of women who sustain fractures of the distal radius.

References: Reference 1: Use of Job-Specific Functional Capacity Evaluation to Predict the Return to Work of Patients with a Distal Radius Fracture. Cheng A, Cheng S. American J. Occupational Therapy 2011;65(4):445-52. Reference 2: Time lost from work following a distal radius fracture. MacDermid J, Roth J, Richards R. JBJS 2008(90B): Suppl I: 92.

♦ No relevant financial relationships to disclose

E-poster 106: Prospective study of Collagenase for Dupuytrens in a Private Practice setting

Category: Evaluation/Diagnosis, Treatment, Prognosis/Outcomes Keyword: Hand and Wrist, Diseases and Disorders Level 2 Evidence

♦ Richard Bernstein, MD

Dupuytren's is a disease of the palmar aponeurosis, most commonly occuring in middle aged males of Northern European decent. Treatment options include observation percutaneous needle aponeurotomy (NA), Collagenase injections and surgery. Most articles regarding collagenase have been industry sponsored presentations. The senior author has, without industry affiliation, prospectively followed a consecutive series of collagenase injections. Since June 2010, all patients presenting to the senior author with classic findings of duputyrens and a MP or PIP contracture which by physical examination findings was a candidate for treatment, were offered collagenase or surgery. Based on surgeon preference, NA was not offered. The study group consisted of 60 contractuers in 37 patients, 30 Males, 7Females mean age 68.3. Three patients had contractures without cords amenable or appropraite for collagenase, and were excluded from the study. All but two patients when explained the options wanted the collagenase injection, instead underwent surgery and were also excluded. Mean MP and PIP contractures were 48.83 and 46.88 respectively. After collagenase and manipulation, there were no tendon ruptures, infections or severe reactions but 9 skin tears occured during manipulation. All patients had a typical flare reaction of various degrees. All skin tears healed uneventfully with conservative management. Three bands ruptured on their own not requring a manipulative lysis. With treatment, there were two complete failures and two incomplete ruptures. Despite the CORD study utilizing up to 3 injections, only two patients required a second injection. Mean correction in the remaining patients was to -8.75 degrees. Though this did not fall into the criteria of correction to 0-5 degrees, patients in the clinical setting were pleased with the correction and did not consider multiple injections. There were significant recurrences in 5 bands in 3 patients, two of which responded to repeat collagenase and 3 required surgical treatment. In a non academic, non industry sponsored setting, collagenase has demonstrated good safety and efficacy, however over time the rate of recurrence has been higher than the author had seen in surgically treated patients and longer term followup will be needed to specifically follow recurrence. Cost can be saved by not performing up to 3 injections as patient satisfaction was high even with a mean correction of greater than 5 degrees. In this prospective nonrandomized level 2 study, collagenase was safe and effective in the majority of Dupuytrens contractures

♦ No relevant financial relationships to disclose

E-poster 107: The Effect of Triamcinolone Acetonide on Idiopathic Carpal Tunnel Syndrome fibroblasts – A Biomechanical Study

Category: Basic Science Keyword: Hand and Wrist, Diseases and Disorders Level 3 Evidence

♦ Tai-Hua Yang, MD ♦ Anne Gingery, PhD ♦ Andrew R Thoreson, MS ♦ Kai-Nan An, PhD ♦ Chunfeng Zhao, MD ♦ Peter Amadio, MD

Hypothesis: Steroid injection is a common conservative treatment for carpal tunnel syndrome (CTS), but the mechanism is unknown. Our hypothesis was that steroid treatment alters subsynovial connective tissue (SSCT) fibroblasts contractile behavior in a cell-seeded gel contraction model.

Methods: The study was approved by our IRB. SSCT fibroblasts were harvested from 5 CTS patients during open carpal tunnel release and 5 cadavers with no antemortem history of CTS. After expansion in cell culture, the SSCT fibroblasts (1.0x106 cells/ml) were resuspened in 0.5 mg/ml collagen/MEM solution and plated on 3.5-cm diameter Petri dishes with a cylinder in the center, creating a donut shaped gel ring. After gelation, Triamcinolone Acetonide (TA) (10.0 µM) or MEM alone was added to the culture media. The contracting gel ring was photographed every 4 hours for 3 days. All contracted area data was fit to an exponential decay function using linear regression and optimization. The decay time constant, was used to characterize the gel contraction behavior. At the end of contraction, gel rings were subjected to uniaxial failure testing using a custom-built micro-test. All measurements were expressed as the mean±SD. Outcomes were analyzed by two-way ANOVA with a Bonferroni post hoc test (p<0.05 indicating significant difference).

Results: Morphologically, in both cell types, gels with TA treatment did not contract completely and showed poorly-defined margins (Fig. 1). The contraction rate of gels with CTS cells was significantly higher than in normal cells. The gel contraction with normal cells was significantly enhanced by TA (Fig. 2A). After TA treatment, the tensile strength of gels with CTS cells was significantly lower than that for normal cells (Fig. 2B). Moreover, the addition of TA significantly increased tensile strength in gels with normal cells. Additionally, the stiffness of gels with CTS cells was significantly higher than that with normal cells (Fig. 2C).

Summary Points: • Without TA treatment, the gel with CTS cells contracted faster and were stiffer compared to gels with normal cells. • TA impeded completion of gels contraction, and resulted in poorly-defined margins formation regardless cell type. • TA enhanced contraction rate and tensile strength in gels with normal cells, and increased stiffness in both cell types. • Further investigation is needed to explore the effect of TA treatment and the mechanisms by with TA affects SSCT fibroblasts, which will provide insight into better biological treatments for CTS.

References: Reference 1: Osamura N, Zhao C, Zobitz ME, et al. 2007. Evaluation of the material properties of the subsynovial connective tissue in carpal tunnel syndrome. Clinical Biomechanics 22:999-1003. Reference 2: Karadas, Ö., et al., Triamcinolone acetonide vs procaine hydrochloride injection in the management of carpal tunnel syndrome : Randomized placebo-controlled trial. Journal of Rehabilitation Medicine, 2012. 44(7): p. 601-604. Reference 3: Cacou C, Palmer D, Lee DA, et al. 2000. A system for monitoring the response of uniaxial strain on cell seeded collagen gels. Med Eng Phys 22:327-333. Reference 4: Carroll LA, Hanasono MM, Mikulec AA, et al. 2002. Triamcinolone stimulates bFGF production and inhibits TGF-ß1 production by human dermal fibroblasts. Dermatologic Surgery 28:704-709

♦ No relevant financial relationships to disclose

E-poster 108: Corticomotor Excitability of the Biceps After Tendon Transfer in Spinal Cord Injury

Category: Therapy/Rehabilitation, Basic Science Keyword: Elbow and Forearm, Diseases and Disorders Level 1 Evidence

♦ Carrie L Peterson, PhD ♦ Lynn M Rogers, PhD ♦ Jeremy P.M. Mogk, PhD ♦ Michael S Bednar, MD ♦ Eric Perreault, PhD ♦ Wendy M Murray, PhD

Hypothesis: Following tendon transfer of the biceps to triceps after cervical spinal cord injuries (SCI), individuals must learn to activate the transferred biceps muscle to extend the elbow. Retraining the transferred muscle to actuate its new function may be facilitated by focusing on upper limb postures in which the biceps is most excitable. In this study, we evaluated corticomotor excitability (i.e., how accessible a muscle is by the motor cortex) in functionally relevant arm postures for both non-impaired and transferred biceps. Because previous studies have demonstrated that changes to peripheral structures can alter cortical function, we hypothesized that the posture in which the biceps is most excitable changes after tendon transfer.

Methods: Corticomotor excitability of the biceps was assessed in twelve non-impaired arms (Mogk JPM et al.) (3 females, 9 males; mean age 26.5 ± 3.3 years) and five arms of individuals with SCI and biceps-to-triceps transfer (3 males; two subjects had bilateral transfers; mean age 29.8 ± 12.0 years; time since surgery = 3.2 ± 1.8 years) using transcranial magnetic stimulation (TMS) delivered at rest. Single-pulse TMS was delivered to the contralateral motor cortex using a figure-of-eight coil in three functionally relevant arm postures (Fig. 1). At each posture, the forearm was positioned in neutral or maximally supinated. Stimulus intensity was set to 120% of the resting threshold in all trials. Motor evoked potentials (MEPs) were recorded via surface electromyography and were normalized to those measured in the horizontal plane posture with the forearm in a neutral position (Fig. 1). Fisher’s exact test was used to compare the proportion of transferred biceps that were most excitable in the same posture as the non-impaired biceps.

Results: In non-impaired subjects, the horizontal, supinated posture resulted in the largest MEPs in all arms tested (12/12 arms). The proportion of transferred biceps where the largest MEPs occurred in this same posture differed (p = 0.015). The largest MEPs from the transferred biceps were observed either when the limb was positioned in the overhead reach, neutral posture (3/5 arms) or in the horizontal, supinated posture (2/5 arms). Summary Points: The data suggest the posture in which the biceps is most excitable may change following SCI and tendon transfer. Ongoing work aims to establish the effect of SCI alone on biceps excitability, as well as the success of the nervous system in adapting to the biceps’ new role as an elbow extensor.

References: Reference 1: Mogk, JPM, Rogers, LM, Murray, WM, Perreault, E, Stinear, JW. Corticomotor excitability of arm muscles modulates according to static position and orientation of the upper limb. Clinical Neurophysiology 2014 (in press).

♦ No relevant financial relationships to disclose E-poster 109: Reducing Cost and Radiation Exposure during the Treatment of Pediatric Greenstick Fractures of the Forearm

Category: Treatment, Prognosis/Outcomes Keyword: Elbow and Forearm, Congenital and Pediatric Problems Level 4 Evidence

♦ Beverlie Ting, MD ♦ Samantha Chase, MD ♦ Leslie A Kalish, ScD ♦ Peter M Waters, MD ♦ Donald S Bae, MD

Hypothesis: We hypothesize that after successful closed reduction of pediatric greenstick fractures of the forearm, there is a low rate of loss of reduction requiring intervention. By reducing the frequency of clinical and radiographic follow-up, we can reduce costs and radiation exposure.

Methods: A retrospective chart review was performed to identify patients ages 2-16 years treated with closed reduction and cast immobilization for greenstick fractures of the forearm at our institution between 2003 and 2013. The frequency of clinical and radiographic follow-up was determined by the treating orthopaedic surgeon. The primary endpoint was loss of reduction requiring intervention based upon the judgment of the treating provider. Time derived-activity- based costing (TDABC) was used for cost analysis. We estimated radiation exposure in consultation with our hospital’s radiation safety office.

Results: One hundred and nine patients (41 females, 68, males) with an average age of 6.9 years (range, 2-15) met inclusion criteria. Both bones were fractured in 68% of cases, with initial fracture angulation averaging 19 degrees (range 2-55 degrees). All patients underwent closed reduction within five days of injury. The initial cast index averaged 0.83 and the three-point cast index averaged 1.36. Patients were followed for an average of 60 days (range, 19-635 days) after initial injury. On average, patients received 3.6 follow-up clinical visits and 4.9 sets of radiographs, comprised of at minimum an AP and lateral radiograph, during treatment. Based on final radiographs, 95% of patients met criteria for acceptable alignment. Only one patient (0.9%, 95% CI =0.2%-5.0%) required re-reduction, as determined by clinical and radiographic follow-up ten days after injury.

Summary: - This retrospective study suggests that pediatric greenstick fractures of the forearm rarely require intervention after initial successful closed reduction. - While the optimal frequency of clinical and radiographic followup is unknown, the results of this study suggest that the cost and radiation exposure may be safely reduced during non- operative care of greenstick forearm fractures.

References: Reference 1: Chung KC, Spilson SV. The frequency and epidemiology of hand and forearm fractures in the United States. J Hand Surg. 2001;26(5):908–915. doi:10.1053/jhsu.2001.26322. Reference 2: Bae DS. Pediatric Distal Radius and Forearm Fractures. J Hand Surg. 2008;33(10):1911–1923. doi:10.1016/j.jhsa.2008.10.013. Reference 3: Davis DR, Green DP. Forearm fractures in children: pitfalls and complications. Clin Orthop. 1976;(120):172–183. Reference 4: Kaplan RSP. How to Solve The Cost Crisis In Health Care. Harv Bus Rev. 2011;89(9):46–64. Reference 5: Matthews L, Kaufer H, Garver D, Sonstegard D. The effect on supination-pronation of angular malalignment of fractures of both bones of the forearm. J Bone Jt Surg. 1982;64(1):14–17 Reference 6: Tarr RR, Garfinkel AI, Sarmiento A. The effects of angular and rotational deformities of both bones of the forearm. An in vitro study. J Bone Joint Surg Am. 1984;66(1):65–70.

♦ No relevant financial relationships to disclose

E-poster 110: Anatomical study of forearm interosseous membrane

Category: Anatomy Keyword: Elbow and Forearm N/A - Not a clinical study

♦ Hitoshi Kiuchi, MD ♦ Kazuki Kuniyoshi, MD, PhD ♦ Keisuke Ueno, MD ♦ Yasufumi Ogawa, MD ♦ Koji Sukegawa, MD ♦ Takane Suzuki, MD,PhD

Hypothesis: Components of the forearm interosseous membrane (IOM) and their existence are still controversial. The most detailed report pointed out that the IOM consists of a distal oblique bundle (DOB), a central band (CB), an accessory band (AC), a proximal oblique cord (POC), and a dorsal oblique accessory cord (DOC). The purpose of this study is clarifying the existence rate of each component and the attachment locations.

Methods: Sixteen forearms from nine fresh frozen cadavers were used. All IOM ligaments were identified, and attachment locations were measured from the tip of the radial styloid process, or from the ulnar head. The proximal and distal attachments of various parts of the IOM was calculated as a percentage of the total length of the radius or the ulna.

Results: The DOB was found in 44 % of the specimens. The ulnar origin and radial insertion of the distal accessory band were 16% and 7% of ulnar or radial length, respectively. The CB was found in all specimens. The radial origin of the CB ranged between 48% and 59% of total radial length from the tip of the radial styloid process, and the ulnar insertion ranged between 29% and 44% of total ulnar length from the ulnar head. The distal AC was found in 81 %. The radial origin and ulnar insertion of the distal accessory band were 41% and 22% of radial and ulnar length, respectively. The proximal AC was found in 56 %. The radial origin and ulnar insertion of the proximal accessory band were 60% and 68% of bone length. The DOC was found in 63 %. The ulnar origin and radial insertion of the cord were 62% and 60% of bone length, respectively. The POC was found in 81 %. The ulnar origin and radial insertion of the cord were 75% and 78% of bone length.

Summary Points: The existence rate and the location of attachment of the portions of the IOM were clarified. The CB always existed, and the distal AC and the POC existed with a high probability. However, the DOB, the proximal AC and the DOC existed only in approximately half of the specimens. Further study is necessary to reveal the biomechanical function of those components.

References: Reference 1: JamesR. SkahenIII, Andrew K. Palmer. The interosseous membrane of the forearm:Anatomy and Function. J Hand Surg 1997;22A:981-985. Reference 2: Jennifer B. Green, David S. Zelouf. Forearm Instability. J Hand Surg 2009;34A:953– 961. Reference 3: Kazuo Noda, Akira Goto. Interosseous Membrane of the Forearm: An Anatomical Study of Ligament Attachment Locations. J Hand Surg 2009;34A:415–422.

♦ No relevant financial relationships to disclose

E-poster 111: Distal Radioulnar Joint Disruption in Distal Radius Fractures: A Novel Classification based on Long-term Clinical Outcomes

Category: Evaluation/Diagnosis, Prognosis/Outcomes, Anatomy Keyword: Hand and Wrist Level 2 Evidence

♦ David Wei, MD, MS ♦ Michael Silverman, BS ♦ Joseph M Lombardi, MD ♦ James A Wilkerson, MD ♦ Melvin P Rosenwasser, MD

Hypothesis: The distal radioulnar joint (DRUJ) is involved in nearly 20% of distal radius fractures, but the current evidence lacks correlation of clinical outcomes with the anatomic congruity of the DRUJ.(1,2) We develop a novel and simple classification system of DRUJ involvement for distal radius fractures using CT imaging of the wrist based on correlation with clinical and functional outcomes.

Methods: We identified patients from a prospective registry of distal radius fractures who received CT scans of their injured wrist between 2004 and 2013 with minimum 1 year follow-up. One- millimeter axial CT slices (Figure 1) through the DRUJ were reconstructed and reviewed by three authors. Radiographic measurements of the DRUJ including, step, gap, congruence, and number of fracture lines were determined independently. A novel classification system was developed based on a priori elements and refined through an iterative process using DASH scores, range of motion, and grip and pinch strength.

Results: A total of 39 patients with distal radius fractures and CT scans of the wrist were included. Mean follow-up time was 2.5 years (range 1 year to 8.5 years). We divided patients into three groups (Figure 1): Type 1 fractures have no involvement of the DRUJ, or have a fracture line that enters the joint but without displacement. Type 2 fractures have fractures line(s) involving the DRUJ but with maintained congruity, step-off 2mm, significant intra-articular comminution, or gross radioulnar abutment. Regardless of treatment, Type 1 fractures had significantly better long- term DASH scores compared to Type 2 and 3 fractures (14 versus 26 points, p<0.05, Figure 2). And, Type 1 and 2 fractures resulted in significantly better long-term supination compared to Type 3 fractures (96% versus 80% of the un-injured wrist, p<0.05).

Summary: 1. A simple novel classification scheme using CT imaging for DRUJ involvement in the setting of distal radius fractures was developed based on long-term patient-reported and functional outcomes. 2.Classification of DRUJ injury may better inform patients and orthopaedic surgeons of long-term prognosis and guide future treatment and research of distal radius fractures.

References: Reference 1: Rozental TD, Bozentka DJ, Katz M a, Steinberg DR, Beredjiklian PK. Evaluation of the sigmoid notch with computed tomography following intra-articular distal radius fracture. J Hand Surg Am. 2001;26(2):244–51. Reference 2: Nakanishi Y, Omokawa S, Shimizu T, Nakano K, Kira T, Tanaka Y. Intra-articular distal radius fractures involving the distal radioulnar joint (DRUJ): three dimensional computed tomography-based classification. Journal of orthopaedic science?: official journal of the Japanese Orthopaedic Association. 2013;18(5):788–92.

♦ No relevant financial relationships to disclose E-poster 112: Decreasing Incidence and Changing Treatment of Distal Radius Fractures Among Elderly Adults

Category: Evaluation/Diagnosis, Treatment Keyword: Hand and Wrist Level 4 Evidence

♦ Benjamin Streufert, BS ♦ Jonathan A Godin, MD, MBA ♦ Robin Kamal, MD ♦ Sendhilnathan Ramalingam, BS ♦ Robert A Henderson, MD, MSc ♦ David S Ruch, MD

Hypothesis: Distal radius fracture (DRF) is the most common upper extremity fracture in the elderly population and a cause of significant morbidity. DRF has been linked to osteoporosis and to subsequent injury, including hip fracture. Several studies in the past two decades have described increases in absolute numbers and incidence of DRF across age groups, including the elderly, but neither recent trends of incidence nor data on treatment in elderly adults in the US are available.

Methods: US Medicare enrollees who were diagnosed with distal radius fracture between 2005 and 2011 were identified by searching ICD-9 diagnosis codes in a comprehensive Medicare hospital claims dataset via the PearlDiver Database (PearlDiver Technologies, Fort Wayne, IN). Treatment of DRF was identified in a 5% Medicare Patient Sample using CPT codes for closed and open fixation. Rates of treatments were compared relative to each other for analysis. Additional procedures and diagnostic testing performed on patients before and after diagnosis of DRF were analyzed. Fractures were stratified according to patient demographics, and comorbidities were examined.

Results: Incidence of DRF: Between 2005 and 2011, 571,384 patients diagnosed with DRF were identified in the Medicare population. Total numbers of DRF increased 6.70% from 83,512 in 2005 to 89,107 in 2011, but the incidence fell 7.17% from 19.65 to 18.24 10,000 person-years over the same period. The age group with the largest decrease in incidence was patients age 85 years and older, with a 22.93% decrease from 64.67 to 49.84 per 10,000 person-years. Gender and regional variation was examined. In the year prior to DRF, a diagnosis of osteoporosis was present in 11.0% of patients, low vitamin D in 1.8%, and tobacco use in 4.7%. Dual-energy x-ray absorptiometry scan was performed in 6.73% in the year before DRF and 8.50% in the year after DRF. Treatment of DRF: In the 5% Medicare sample, 29,570 patients were treated with closed or open fixation for DRF from 2005 to 2011. Closed treatment represented 79.6% of the total treated, but the proportion treated with open fixation rose from 21.2% in 2007 to 29.4% in 2011. Trends were examined for treatment of various fracture patterns in total and by region and gender.

Summary Points: • Decreased incidence despite increased absolute increases in DRF from 2005 to 2011 in US elderly adults. • Increased treatment of DRF by open fixation. • Uncertain effects of bone density management in contributing to DRF or after fracture.

♦ No relevant financial relationships to disclose

E-poster 113: Social Impact of Peripheral Nerve Injuries

Category: Evaluation/Diagnosis Keyword: Nerve Level 3 Evidence

♦ Danielle Wojtkiewicz, OT ♦ Christine B Novak, PT, PhD ♦ Leahthan Domeshek, MD ♦ James Saunders, MD ♦ Susan E Mackinnon, MD

Hypothesis: This study evaluated the relationship among psychosocial factors and different nerve diagnoses. We hypothesized that: 1) patients with single, traditionally non-painful, compression neuropathies report lower pain, depression, stress, and higher quality of life (QoL) than patients with multiple or other, more historically severe or painful peripheral nerve diagnoses; and 2) patients with neuromas have the highest negative ratings across similar outcome measures.

Methods: A retrospective chart review was performed and included adult patients presenting to the senior author’s clinic between 2010 and 2012 with peripheral nerve compressions, brachial plexus injuries, thoracic outlet syndrome (TOS) or neuromas. Demographic data (age, sex, handedness, height and weight) and the initial intake questionnaires were used to compare the following variables: 1) average level of pain over the last month; 2) self-perceived depression; 3) how much pain impacts QoL; 4) current level of stress at home and at work; 5) ability to cope with stress at home and at work. The primary clinical diagnoses were classified as: 1) brachial plexus; 2) TOS; 3) single nerve compression; 4) multiple nerve compression; 5) ulnar nerve diagnosis other than cubital tunnel syndrome; 6) peroneal nerve compression (superficial or deep branch); 7) tarsal tunnel; and 8) neuroma. Statistical analyses were performed to assess the differences between diagnostic groups (Kruskal-Wallis test) and demographic groups (Mann-Whitney U test or Spearman correlations).

Results: There were 490 patients (mean age 50 ± 15 years) and the most common diagnosis was single nerve compression (n = 212). Pain-related impact on QoL and level of stress at work were significantly higher in patients with peroneal nerve compression (p = .02) and neuroma (p = .04) compared to single, nerve compressions. Level of pain, impact on QoL and stress at home were significantly higher in females (p < .01). Stress at work was significantly higher in patients with neuromas (p = .02) compared to patients with brachial plexus injuries. Impact on QoL was correlated with pain (r = .65), depression (r = .53), stress at home (r = .47) and coping at home (r = .41). Summary: Our results indicate significant differences in psychosocial factors among different nerve compression and injury diagnoses. The impact on QoL was strongly correlated with pain and depression and patients with neuromas and peroneal nerve entrapments reported a greater impact on QoL. Longitudinal prospective studies are necessary to evaluate these relationships and the psychosocial variables with treatment and recovery.

♦ No relevant financial relationships to disclose

E-poster 114: Telephone Clinic Follow-Up Following Carpal Tunnel Decompression: A 7-Year Review Of Service

Category: Prognosis/Outcomes, Patient Education, Billing/Coding Keyword: Hand and Wrist, Practice Management Level 3 Evidence

♦ Clement Leung, MBBS ♦ Ahmed Magan, BMBSc,MRCS

Hypothesis: With increasing pressure on provision in the National Health Service (NHS), there is a need for alternative methods of determining patient satisfactory following surgery and surgery outcome. We investigated the feasibility of using telephone clinics in the routine follow-up of patients following carpal tunnel decompression (CTD), and reviewed the service since its implementation.

Methods: The senior author provided training in the natural history and potential complications of CTD. Between 2004 and 2011, all patients undergoing primary CTD were offered a telephone clinic follow-up appointment 6 weeks post-surgery, with the option to decline in favour of a traditional outpatient clinic appointment. A questionnaire was developed with which to assess levels of patient satisfaction with the service and to identify patients who require referral to hand therapy, or to outpatient clinic in 2 weeks time to address poor results or complications. In addition, a cost analysis was performed to quantify any possible advantages of this method of follow-up.

Results: In 7 years, 2529 patients entered into the study. 93% (2336 of 2497) were satisfied with their treatment and review process. 6% (161) were dissatisfied and requested surgical review. The reasons for consultation was altered sensation 27%, no change in symptoms 27%, scar tenderness 17%, weakness 13%, swelling 10%, pain at base of thumb 3%, and ulnar nerve dysasthesia 3%. The revision rate was less than 1%. The cost of employing the surgical care practitioner was £10.50/hour, and the clinics took place every 2 weeks lasting 3.5 hours. There were 123 clinics in 7 years, and therefore the employment cost was £4520.25. Administrative support, estimated at 15% (£678.04), was added. Each telephone contact lasted about 10 minutes. With the mean cost of a standard telephone call at £0.20/minute, the overall telephone cost was £4994. The cost of an outpatient follow-up was £95 per attendance, resulting in a total cost £13,585 for 143 patients. The estimate cost of following up the entire cohort of patients would have been £237,215. Cost analysis calculation estimated a potential saving of £227,022 over the 7-year period when compared to standard outpatient consultation.

Summary Points: This model of follow-up benefits both patients and hospital. It is a time effective method of assessing surgery outcome. As a result of high satisfactory rate and cost efficiency, we recommend that patients undergoing similar minor hand surgery should use a telephone clinic follow-up.

References: Reference 1: Williams M et al. Telephone clinic follow-up following carpal tunnel decompression. J Hand Surg Eur Vol. 2008; 33(5): 641-4.

♦ No relevant financial relationships to disclose

E-poster 115: Reliability of Radiographic and Magnetic Resonance Imaging of SLAC Wrist Arthritis

Category: Evaluation/Diagnosis, Anatomy Keyword: Hand and Wrist Level 3 Evidence

♦ Lauren ElizabethLaMont, MD ♦ Steve K Lee, MD ♦ Alexia Hernandez-Soria, MD ♦ Nadja Farshad, MD ♦ Hollis Potter, MD ♦ Scott W Wolfe, MD

Hypothesis: Scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) were originally described as three-stage progressive arthritic patterns that spared the radiolunate joint. Pancarpal arthritis has been postulated to represent a Stage IV on the SLAC/SNAC continuum; however rigorous analysis of its prevalence has not been performed using standard or advanced imaging protocols. The purpose of our study is to compare the inter- and intra-rater reliability of standard radiographs and magnetic resonance imaging (MRI) in the assessment of cartilage wear in a cohort of patients with SLAC or SNAC arthritis. We hypothesize that MRI has higher inter- and intra-rater reliability for assessment of cartilage wear than standard radiographs.

Methods: A retrospective surgical cohort of thirty-one patients with SLAC or SNAC arthritis were studied with radiographs and cartilage-sensitive MRI. Two board-certified hand surgeons and two board- certified musculoskeletal radiologists read the blinded radiographs and MR images on two occasions 4 or more weeks apart. The styloid-scaphoid, radioscaphoid, capito-lunate, and radiolunate joints were independently graded using the Kelgren-Lawrence scale and assigned a SLAC stage. Similarly, cartilage wear was graded using MRI as normal, superficial, or deep wear. The inter- and intra-rater reliability of the Kelgran-Lawrence scale and the MRI classification were assessed as well as a trend analysis between the two modalities.

Results: SLAC and SNAC radiographic grade had substantial agreement for both intra- and inter-rater reliability based on weighted Kappa statistics with 95% confidence intervals. Radiographic grading of each individual joint demonstrated lower inter-observer reliability. Substantial inter- observer reliability was demonstrated in the radiolunate joint; the radioscaphoid and capitolunate had moderate agreement and the radial styloid had slight agreement. Greater inter- rater reliability was seen across joints graded by MRI. The radial styloid and radioscaphoid joints demonstrated almost perfect agreement. The capitolunate joint had substantial agreement and the radiolunate demonstrated moderate agreement. Twenty one patients had normal radiolunate joints on radiographs but demonstrated cartilage wear on MRI, and four of those patients had deep cartilage wear. Six patients demonstrated full thickness cartilage loss on the dorsal radiolunate lip.

Summary Points: Radiographic staging of SLAC and SNAC arthritis has substantial intra- and inter-observer agreement; however, the grading of individual joint arthritis is less reliable. MRI of individual joints demonstrated greater inter-observer reliability for cartilage wear and demonstrated a concerning degree of radiolunate cartilage loss. MR cartilage-sensitive sequencing identified stage IV SLAC changes that were missed by radiographs, and may be a more appropriate assessment of cartilage loss.

References: Reference 1: Watson HK, Ballet FL. The SLAC wrist: scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg Am. 1984 May;9(3):358-65.

Tables 1 and 2

♦ No relevant financial relationships to disclose

E-poster 116: Management of Wrist Extension Loss Following Volar Plating of Distal Radius Fractures

Category: Treatment, Surgical Technique Keyword: Hand and Wrist Level 4 Evidence

♦ Robin Kamal, MD ♦ Marc J. Richard, MD ♦ David S. Ruch, MD

Hypothesis: Wrist flexion contracture, loss of wrist extension, and loss of pronosupination are potential complications of operatively treated distal radius fractures. We hypothesized that wrist flexor tenolysis, volar capsule and extrinsic ligament release, and removal of hardware would lead to improved wrist range of motion.

Methods: We conducted a retrospective review of all patients who underwent a volar capsule and extrinsic ligament release for a flexion contracture after volar distal radius plating from 2006 to 2012 at our institution. Indications for the procedure included a healed distal radius fracture with less than 2 mm of ulnar variance and an acceptable palmar tilt of at least neutral alignment and wrist extension of less than 40 degrees despite 6 months of conservative therapy. All patients underwent a procedure consisting of tenolysis of the FCR tendon first, removal of hardware next, and finally subperiosteal dissection of the volar capsule and volar extrinsic ligaments. If supination was limited, the volar distal radioulnar ligament was released. Paired two-tailed T- tests were used to compare pre-operative and post-operative range of motion, Visual Analog Scale (VAS) pain scores, and Disabilities of Arm, Shoulder, and Hand (DASH) scores with significance set at p<0.05.

Results: Twelve patients with an average age of 45 were treated with tenolysis, removal of hardware and volar capsular release with an average follow up of 1.5 years. Four patients had release of the volar DRUJ ligament. Intraoperative findings indicated wrist extension was not increased until after the volar capsule was released. Average wrist flexion improved by 22.10 from 38.80±11.7 to 60.80±15.3 (p=.0002), extension improved by 31.70 from 23.80±14.3 to 55.40±12.0 (p<.0001),pronation improved by 12.10 from 59.60±13.2 to 71.70±6.2 (p=.0007), supination improved by 23.30 from 42.50±14.8 to 65.80±12.9 (p<.0001), DASH decreased by 30 points from 47.3±15.1 to 16.6±12.9 (p<.0001), and VAS changed from 2.8±1.3 to 2.5±1.0 (p=.177). Patients with malunions or intraarticular step off did not have significant gains in wrist range of motion or improvement in DASH scores.

Summary Points: • Volar capsule and volar extrinsic ligament release is a reliable method of gaining significant wrist extension after distal radius fracture • DASH scores were significantly improved by volar capsular release, while VAS was not • Malunion limited improvement in wrist range of motion and DASH despite capsular release

♦ No relevant financial relationships to disclose

E-poster 117: Use of Peripheral Nerve Transfers in Tetraplegia: Early Functional Outcomes

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist, Nerve Level 2 Evidence

♦ Ida K.Fox, MD ♦ Christine B. Novak, PhD ♦ Gwendolyn M Hoben, MD, PhD ♦ Kristen M Davidge, MD, MSc ♦ Lorna C. Kahn, PT ♦ Susan E. Mackinnon, MD

Hypothesis: The novel use of nerve transfers to improve upper extremity function in cervical spinal cord injury (SCI) patients has been reported. We hypothesized that individualized nerve transfer procedures in this unique patient population would improve both objective and subjective function

Methods: A prospective clinical outcomes study design was used. After approval from our institutional ethics review board, all patients with cervical SCI who underwent peripheral nerve transfer surgery to improve hand function were recruited for inclusion. Patients were followed for at least 11 months after initial surgery. Demographic and surgical procedure data were collected. Outcomes measures included patient-reported subjective functional gains and the change in manual muscle testing results of recipient muscles.

Results: Six male patients have had nerve transfer surgery, mean age 32 years (range 21-55), mean time from SCI 7 years (range 0.75 to 13). One patient, who was lost to follow-up due to a move, underwent staged bilateral procedures for a total of seven extremities treated. A representative schematic of the surgeries performed is shown in Figure 1. All patients had intact volitional biceps and brachialis (+/- brachioradialis) to power elbow flexion and no volitional hand function. The nerve to the brachialis muscle was used as the expendable donor in all cases. Recipient nerves included the anterior interosseous nerve (AIN), to restore volitional prehension, as well as nerve branches to the flexor carpi radialis (FCR) and flexor digitorum superficialis (FDS). Two patients underwent additional nerve transfers: one had supinator to extensor carpi ulnaris (ECU); the second had deltoid to triceps. The procedure(s) performed and results are presented in Table 1. No patients had any loss of their baseline upper extremity function. Early follow-up reveals gain in MRC grade function of recipient muscles at 8-12 months post-transfer. Four of five patients also report subjective improvement in function.

Summary Points: • Nerve transfers provide a reliable means to re-establish volitional control of upper extremity function in people with cervical level SCI. • Despite subtle objective gains, which are expected at this early time point as function will continue to improve for years after nerve transfer, patients report new and improved subjective function. • This surgery does not downgrade existing function, uses expendable donor nerve, and has minimal perioperative down time for patients, which might make it a more viable option than traditional tendon transfers for tetraplegia.

Table 1: Patient Specific Data

♦ No relevant financial relationships to disclose

E-poster 118: Comparison of Compression Screw and Perpendicular Clamp in Ulnar Shortening Osteotomy

Category: Surgical Technique, Basic Science Keyword: Hand and Wrist, Elbow and Forearm N/A - Not a clinical study

♦ Scott H Kozin, MD ♦ Stephanie A. Russo, BS ♦ Dan A. Zlotolow, MD ♦ Daniel E Martin, MD

Hypothesis: This study hypothesized the use of compression screw or perpendicular clamp, two surgical techniques commonly employed during ulnar shortening osteotomy (USO), are equivalent techniques for generating compression, which promotes primary bone healing and thus decreases the risk of delayed union or nonunion. The primary outcome was the generation of force across the osteotomy site, as measured using a digital pressure sensor.

Methods: Fourteen fresh-frozen cadaveric human forearms were randomly assigned to two groups. Group I (n=7) underwent USO according to traditional Arbeitsgemeinschaft für Osteosynthesefragen (AO) plate fixation technique, utilizing a screw placed eccentrically in an oblong hole to generate compression at the osteotomy site (Figure 1). Group II (n=7) underwent USO using a commercially-available USO plating system, utilizing a clamp placed perpendicular to the osteotomy site to generate compression (Figure 1). Both techniques involved a 2mm osteotomy performed with cutting jigs to minimize variability and an interfragmentary lag screw to augment compression. A digital pressure sensor measured contact area at the osteotomy site and average pressure in the observed contact area, and these values were used to calculate force across the osteotomy site. Measurements were obtained after the following steps: reduction of osteotomy, compression screw placement (Group 1 only), lag screw placement, and final construct with all clamps removed. Two-way analysis of variance (ANOVA) with repeated measures on one factor (a = 0.05) was used to determine the effects of fixation technique (Groups I and II) and stage of fixation (reduction, lag screw placement, and final construct). Significant main effects were evaluated with Tukey honestly significant difference (HSD) post hoc tests (a = 0.05).

Results: Group II demonstrated significantly greater force than Group I (Figure 2A), and lag screw placement resulted in significantly increased force independent of fixation technique (Figure 2B). The effect of the lag screw on force was maintained after clamp removal. While technique of fixation did not significantly influence contact area (Figure 2C), lag screw placement significantly increased contact area independent of fixation method (Figure 2D). However, this effect was not maintained after clamp removal. Average pressure in the observed contact area was not significantly influenced by fixation technique (Figure 2E) or stage of fixation (Figure 2F).

Summary Points: - Perpendicular clamp compression significantly increased force as compared with traditional compression screw technique. - Lag screw placement significantly increased force in both constructs. - Larger compressive forces across the osteotomy may promote primary bone union and decrease the rates of delayed union or nonunion.

♦ No relevant financial relationships to disclose

E-poster 119: Shoulder Function Following Delayed or Late Nerve Surgery after a Brachial Plexus Birth Injury

Category: Surgical Technique, Prognosis/Outcomes Keyword: Congenital and Pediatric Problems, Nerve Level 3 Evidence

♦ John A.I. Grossman, MD, FACS ♦ Herbert Valencia, RN, CFA ♦ Rachel Sarshalom, OTR/MA ♦ Yvette Elias, OTR, CHT ♦ Leslie Grossman, AA ♦ Andrew E Price, MD

Hypothesis: Previous reports have documented benefit, especially with regard to shoulder function, from nerve surgery after 9 months of age in selected infants with brachial plexus birth injuries. This study investigates a large series of cases operated between 9-36 months of age to confirm this observation.

Methods: A retrospective review was done on 401 nerve reconstructions by the senior author between 1997 and 2010 for brachial plexus birth injury. One hundred and five infants were operated at 9 months or later. Fifty-one were considered “delayed,” being treated at 9-11 months. Fifty-four were considered “late,” operated at 12 months or more. In the late group, 24 underwent only nerve surgery and 30 had a simultaneous nerve and shoulder reconstruction. Nerve procedures consisted of either neurolysis alone or combined with grafting or a spinoscapular transfer. No complications or clinical downgrades occurred. Minimum follow-up was 2 years and all children had their shoulder function evaluated using the Miami Shoulder Score. Functional assessment also was conducted using the Toronto scale.

Results: Combined good-excellent results varied depending on time of surgery. 9-11 months 84.4% 12-18 months 69.5% 19-24 months 72.8% >24 months 66.7% Failure rate was highest in the neurolysis group and lowest in infants who underwent a spinoscapular nerve transfer.

Summary Points: • Infants with brachial plexus birth injuries can benefit from surgery after 9 months of age to improve shoulder function. • Spinoscapular nerve transfer appears to be the superior technique.

♦ No relevant financial relationships to disclose

E-poster 120: Osteophyte excision without cyst excision for a mucous cyst of the finger

Category: Treatment, Surgical Technique Keyword: Hand and Wrist, Diseases and Disorders Level 4 Evidence

♦ Hyun-Joo Lee, MD ♦ Sukjoong Lee, MD

Hypothesis: Osteophyte excision is a mainstay of treatment for mucous cyst combined with Heberden’s node in a distal interphalangeal joint or in an interphalangeal joint of the thumb. The aim of this study was to evaluate the results of osteophyte excision without cyst excision for the treatment of a mucous cyst combined with Heberden’s node.

Methods: The medical records of 37 patients (42 cases) with a mucous cyst with Heberden’s node were retrospectively reviewed. Thirty-eight of 40 cases with available pre-operative simple radiographs showed evidence of joint arthrosis. A T-shaped skin incision of the joint capsule between the extensor tendon and lateral collateral ligament was used. Osteophyte excision without cyst excision was performed.

Results: All cysts, except one, regressed without recurrence or a skin complication after osteophyte excision, but eight cases showed post-operative pain and loss of range of motion.

Summary Points: Osteophyte excision without cyst excision may be a good treatment choice for mucous cyst of the finger.

References: Reference 1: Gingrass MK, Brown RE, Zook EG. Treatment of fingernail deformities secondary to ganglions of the distal interphalangeal joint. J Hand Surg Am. 1995, 20: 502–5. Reference 2: Shin EK, Jupiter JB. Flap advancement coverage after excision of large mucous cysts. Tech Hand Up Extrem Surg. 2007, 11: 159–62. Reference 3: Dodge LD, Brown RL, Niebauer JJ, McCarroll HR, Jr. The treatment of mucous cysts: long-term follow-up in sixty-two cases. J Hand Surg Am. 1984, 9: 901–4. Reference 4: Kasdan ML, Stallings SP, Leis VM, Wolens D. Outcome of surgically treated mucous cysts of the hand. J Hand Surg Am. 1994, 19: 504–7.

♦ No relevant financial relationships to disclose

E-poster 121: The First Dorsal Interosseous: Implications for Thumb Carpometacarpal Arthritis Intervention?

Category: Therapy/Rehabilitation Keyword: Hand and Wrist N/A - Not a clinical study

♦ Sara Van Nortwick, MD ♦ Corey McGee, OTR, CHT ● Julie E. Adams, MD ♦ VIrginia O'Brien, OTR, CHT ♦ Ann E. Van Heest, MD

Hypothesis: Activation of the first dorsal interosseous (FDI) will reduce subluxation of the first metacarpal on the trapezium as measured by fluoroscopy.

Methods: Subjects at least 18 years old were recruited. Exclusion criteria included positive grind test, pregnancy, and major conditions of ligamentous laxity. A certified hand therapist performed a grind test on all subjects. Maximal voluntary contraction of the FDI using the Rotterdam Intrinsic Myometer, lateral pinch strength, and grip strength were measured. Fluoroscopy was used to obtain true AP radiographs of the CMC joint at 1) rest, 2) while stressed without activation of the FDI and 3) while stressed with activation of the FDI. Radial subluxation of the base of the first metacarpal and metacarpal articular width were measured by 3 blinded surgeons as described by Wolf (2011). The ratio of radial subluxation to the articular width was calculated.

Results: Seventeen subjects with 34 thumbs including 5 males and 12 females participated. Average age was 25.9 (21-59). Thirteen right handed, one left handed, and 3 ambidextrous subjects were included. Two thumbs were excluded for a positive grind and one for poor radiograph quality. Thirty-one thumbs were evaluated. Average maximal voluntary contraction of the FDI was 27N, lateral pinch 81N, and grip strength 347N. Twenty-six thumbs demonstrated subluxation when stressed and reduction after firing of the FDI. Three thumbs were not subluxed at rest and did not sublux with stress or reduce with firing of the FDI, consistent with stiff CMC joints. Two thumbs were subluxed at rest but did not further sublux with stress. Inter-rater reliability was high (96%). Average articular width was 1.2 cm (0.9- 1.8). In the 26 thumbs that demonstrated increased subluxation with stress, subluxation while stressed averaged 0.6 cm (0.0-0.9) or 48% (29-75) of articular width. FDI activation reduced subluxation by an average of 0.5 cm (0.1-0.9) or 80% (20-120). The two thumbs with the same degree of subluxation at rest and with stress had subluxation of 0.5 cm and 0.7 cm corresponding to 43% and 63% of articular width, respectively. Reduction with FDI activation was by 0.3 cm and 0.2 cm or 67% and 28%, respectively.

Summary Points: Hypermobility of the carpometacarpal (CMC) joint is a well described major etiological factor in the development of thumb arthritis. The FDI radiographically reduced subluxation of the thumb CMC joint in this study. Strengthening the FDI may be an effective in preventing thumb arthritis.

References: Reference 1: Wolf JM, Schreier S, Tomsick S, Williams A, Petersen B.Radiographic laxity of the trapeziometacarpal joint is correlated with generalized joint hypermobility. J Hand Surg Am. 2011 Jul;36(7):1165-9.

● Royalty: Biomet Consulting Fee: Arthrex, Articulinx Other (Please describe): Elsevier (honorarium) (Adams)

♦ No relevant financial relationships to disclose

E-poster 122: Incidence of Ulnar Nerve Instability in Patients Considered for in Situ Ulnar Nerve Decompression

Category: Evaluation/Diagnosis, Treatment, Surgical Technique Keyword: Elbow and Forearm, Nerve Level 3 Evidence

♦ Jonas L Matzon, MD ● Kevin Lutsky, MD ♦ C. Edward Hoffler, II, PhD MD ♦ Nayoung Kim, BS ♦ Pedro Beredjiklian, MD

Hypothesis: The incidence of ulnar nerve instability in patients considered for in situ ulnar nerve decompression is unknown, and pre-operative risk factors for ulnar nerve instability necessitating transposition have yet to be identified. We hypothesized that a relatively high percentage of patients considered for in situ ulnar nerve decompression will require transposition secondary to ulnar nerve instability.

Methods: Using our surgical database, we retrospectively identified all patients undergoing surgical treatment of cubital tunnel syndrome by three surgeons over a five-year period. We included all patients who were candidates for in situ ulnar nerve decompression. Patients requiring ulnar transposition due to revision surgery, elbow arthritis, or elbow contracture were excluded. Three hundred sixty three patients met inclusion criteria. We collected demographic data including age, weight, height, and body mass index (BMI). Patients with pre-operative radiographs had measurements of ulnar groove and medial epicondyle morphology. We recorded the number of patients who underwent ulnar nerve transposition due to ulnar nerve instability, and we evaluated whether ulnar nerve instability was diagnosed pre-operatively, intra-operatively following decompression, or post-operatively. We performed unpaired t-tests to assess statistical differences between patients undergoing decompression and patients requiring transposition.

Results: Of the 363 patients who were considered for in situ ulnar nerve decompression, 76 patients (21%) required ulnar nerve transposition secondary to ulnar nerve instability. Twenty-nine patients (8%) were diagnosed with instability pre-operatively, while 44 patients (12%) were identified with instability intra-operatively following in situ decompression. Three patients (1%) were not diagnosed with instability until post-operatively and subsequently underwent delayed transposition. Patients who required transposition due to instability were significantly younger (p<0.0002), taller (p<0.03), and had a lower BMI (p<0.05) than patients without instability. For those patients with pre-operative radiographs, height and width of the ulnar groove and slope of the inferior aspect of the medial epicondyle did not correlate with the need for transposition.

Summary Points: 1. In situ ulnar nerve decompression is an acceptable treatment for cubital tunnel syndrome, but a relatively high percentage of patients will require transposition secondary to ulnar nerve instability. 2. While patient age, height, and BMI correlate with the need for ulnar nerve transposition, further research is necessary to determine which patients are at greatest risk for ulnar nerve instability following decompression. 3. Meticulous pre-operative evaluation for ulnar nerve instability is recommended to aid in appropriate patient counseling and surgical scheduling.

References: Reference 1: Calfee RP, Manske PR, Gelberman RH, Van Steyn MO, Steffen J, Goldfarb CA. Clinical assessment of the ulnar nerve at the elbow: reliability of instability testing and the association of hypermobility with clinical symptoms. J Bone Joint Surg Am. 2010 Dec 1;92(17):2801-8. Reference 2: Goldfarb CA, Sutter MM, Martens EJ, Manske PR. Incidence of re-operation and subjective outcome following in situ decompression of the ulnar nerve at the cubital tunnel. J Hand Surg Eur Vol. 2009 Jun;34(3):379-83.

● Consulting Fee: Synthes (Lutsky)

♦ No relevant financial relationships to disclose

E-poster 123: FDA Approved Orthopaedic and Hand Surgery Devices: A 20-year Analysis

Category: Billing/Coding Keyword: Hand and Wrist Level 3 Evidence

♦ Nana Owusu-Sarpong, BS

Hypothesis: We hypothesized that the increase in medical device recalls in the orthopaedic industry, especially in hand surgery, may be related to the FDA 510(k) approval method for medical devices. This method generally exempts devices from stringent review requiring clinical trials if they prove to be “substantially equivalent” to existing devices.

Methods: Using the FDA’s 510(k) database, we aggregated device approvals from 1992-2012 for all specialties, orthopaedics, and a pool of 12 companies that specialize in hand surgery. Using a Wald test with binomial distribution based on a generalized linear models strategy, we compared the trend in 510(k) device approvals for hand surgery and orthopaedics versus all specialties combined. Significance was determined based on the two-way group x time interaction for comparing slopes over time. Furthermore, we evaluated the top 20 companies with the most recalls from 2002-2012.

Results: From 1992-2012, there were increases in the number of orthopaedic and hand surgery devices approved under the 510(k) review. In the same time period, the total number of medical devices approved under the 510(k) review in all specialties decreased. Using the Wald test, we found that the differences in device approval trends were statistically significant (Figure 1; p<0.001). Using the recalls database, we found that 25% and 20% of the top 20 companies with the most recalls were orthopaedic and hand surgery companies, respectively. These companies include: Stryker Howmedica Osteonics, Depuy Orthopaedics, Zimmer Inc, Biomet Inc, and Smith & Nephew (Figure 2).

Summary Points: • The 510(k) review does not require any new clinical and safety trials, and ultimately leads to an imprimatur “FDA approved” stamp on many new medical devices. In the last 20 years, this has been the primary way orthopaedic and hand surgery devices have been brought into the market. • In contrast, new medical devices in all other specialties combined are increasingly being approved by the more stringent PMA process. • Among the top 20 companies with the most recalls, 25% and 20% belong to orthopaedic and hand surgery industry, respectively. Furthermore, the top 4 contributors of overall recalls were companies that specialized in hand surgery. • The increase in number of devices approved via the 510(k) process for orthopaedic hand surgery may account for the increase in number of recalls during the same time period. • This study highlights the importance of post-market surveillance of medical devices by both the FDA and manufacturers.

Figure 1: Trends in medical devices approved under 510(k) review (Wald test: p<0.001)

Figure 2: Percentage of total recalls for top 20 recalled companies, 2002-2012. (Hand surgery companies are highlighted in red)

♦ No relevant financial relationships to disclose

E-poster 124: Combined Cubital and Carpal Tunnel Release Results in Symptom Resolution Outside of the Median or Ulnar Nerve Distributions

Category: Prognosis/Outcomes Keyword: Elbow and Forearm, Nerve Level 3 Evidence

♦ Peter C Chimenti, MD ♦ Warren C Hammert, MD ♦ John C Elfar, MD

Hypothesis: We hypothesized that patients undergoing combined cubital and carpal tunnel release would experience resolution of subjective symptoms including pain, numbness, and tingling outside of the canonical median or ulnar nerve distributions.

Methods: 20 patients with combined cubital and carpal tunnel syndrome were prospectively enrolled. Inclusion criteria included electrodiagnostic (EDX) evidence of isolated ulnar nerve compression at the elbow and median nerve compression at the wrist. Exclusion criteria included diabetes, cervical radiculopathy, or polyneuropathy on electrodiagnostics. The upper extremity was divided into six zones and the location of pain, numbness, tingling, or strange sensations was recorded pre-operatively. Two-point discrimination, Semmes-Weinstein monofilament testing, and validated questionnaires were collected pre-operatively and at early six-week follow-up. Paired T-tests or non–parametric Wilcoxon Rank tests were used where appropriate to examine for significant (p=0.05) changes between pre- and post-operative scores.

Results: 70% of the cohort pre-operatively reported symptoms not referable to the median or ulnar nerve distributions. Greater than 80% of symptom reports outside of the surgically treated distribution resolved at early follow-up. Probability of resolution was greater in the median than ulnar nerve distribution. There was a decrease in pain as measured by several validated questionnaires.

Summary Points: • 70% of patients in this cohort with EDX-proven isolated cubital and carpal tunnel syndrome reported experiencing symptoms of pain, numbness, tingling, or strange sensations outside of the typical median or ulnar nerve distributions pre-operatively. • More than 80% of those symptom reports improved at early 6-week follow-up. • Statistically significant resolution of symptoms was documented outside of the surgically treated distribution. • Data from this report can be used to improve the quality and accuracy of pre-operative counseling for patients undergoing combined cubital and carpal tunnel release.

References: Reference 1: Elfar JC, Calfee RP, Stern PJ. Topographical assessment of symptom resolution following open carpal tunnel release. J Hand Surg Am. 2009;34:1188-1192.

♦ No relevant financial relationships to disclose

E-poster 125: Relative Prevalence of Congenital Upper Extremity Anomalies in the United States

Category: Evaluation/Diagnosis Keyword: Hand and Wrist, Congenital and Pediatric Problems Level 2 Evidence

♦ Lindley Wall, MD ♦ Ann E. Van Heest, MD ♦ Deb Bohn, MD ♦ Patrick Moen, BS ♦ Charles A. Goldfarb, MD

Hypothesis: The incidence of upper extremity congenital anomalies in the United States has not been established. Utilizing the recently accepted Oberg, Manske, and Tonkin (OMT) classification, we examined the relative prevalence at two large centers. Concurrently, we assessed the utility of this new classification system.

Methods: 664 individuals with 676 congenital upper extremity anomalies were identified at two large metropolitan centers over a one year period. Using medical records and radiographs, the specific upper extremity anomaly and any associated syndrome were documented. We applied OMT classification independently at the two institutions; we also assessed the ease and utility of the OMT.

Results: All congenital anomalies were able to be classified and we found utilization of the OMT to be straightforward. 452 extremities (67%) had a limb malformation, and 172 involved the entire limb. Arthrogryposis was the most common of these (57 extremities). 280 (62%) were abnormal axis formation/differentiation of the hand plate. Radial polydactyly (15%) was most common, followed by symbrachydactyly (11%), and cleft hand (8%). Deformations were seen in 90 extremities (67% trigger digits) and dysplasias were noted in 104 extremities, with multiple hereditary exostosis most common (56%). A total of 82 children had a syndrome or association. The most common syndrome associated with a hand anomaly was VACTERL association.

Summary Points: • The most common anomaly was malformations of the hand plate, involving 62% of the cohort, with radial polydactyly identified as the most common sub-category. • The most common diagnosis overall was trigger digit, 9% of the entire cohort. • The most common associated syndrome was VACTERL. • The OMT classification was able to be applied to all patients in the cohort.

References: Reference 1: Ekblom AG, Laurell T, Arner M. Epidemiology of congenital upper limb anomalies in Stockholm, Sweden, 1997 to 2007: Application of the Oberg, Manske, and Tonkin Classification. J Hand Surg 2014;39(2):237-248. Reference 2: Oberg KC, Feenstra JM, Manske PR, Tonkin MA. Developmental biology and classification of congenital anomalies of the hand and upper extremity. J Hand Surg 2010;35A:2066-2076. Reference 3: Koskimies E, Lindfors N, GIssler M, Peltonen J, Nietosvaara Y. Congenital upper limb deficiencies and associated malformations in Finland: A population-based study. J Hand Surg 2011;36A:1058-1065. Reference 4: Giele H, Giele C, Bower C, Allision M. The incidence and epidemiology of congenital upper limb anomalies: A total population study. J Hand Surg 2001;26A:628-634.

♦ No relevant financial relationships to disclose

E-poster 126: Nerve Transfer Surgery for Penetrating Upper Extremity Injuries

Category: Treatment Keyword: Hand and Wrist, Elbow and Forearm, Nerve Level 4 Evidence

♦ Aamir Siddiqui, MD ♦ Efstathios Karamanos, MD ♦ Theodore Wilkins, B.S. ♦ Anna T Wang, PhD

Hypothesis: Nerve transfer surgery is an option for those who sustain penetrating injuries of the upper extremity. In the right setting it has many advantages over tendon transfers and nerve grafting. Longitudinal monitoring confirm its utility.

Methods: We reviewed our experience over the last 10 years of nerve transfer surgery in the upper extremities. We included cases performed for penetrating trauma, within 3 months of the injury with a minimum of 3 years follow up. Sixteen cases are presented.

Results: All cases were males between 16 and 43 years old. 6 were performed for elbow flexion, 5 for finger extension, 3 for finger flexion and 2 for wrist pronation. 56% had associated vascular injury and 25% had associated fractures. Average follow up was over 6 years. There were no perioperative complications. Each patient had 2-5 operations following the initial trauma (mean 3.7). All patient received physical therapy. We tested the muscle group of interest for all patients before and after the surgery. All patients improved from 0/5 preoperative to a mean of 3.8/5 (range 2/5 to 5/5). This was achieved within 1 year of the nerve transfers. In all cases the strength was maintained and in 50% there was continued improvement after year one. 63% returned to previous level of employment. Mean DASH score improved from 68 to 83 after the nerve transfer surgery.

Summary Points: Nerve transfer is a safe and consistently effective technique for correcting penetrating trauma- related nerve injury. In the appropriate patient it offers many advantages over other techniques including tendon transfer and nerve grafts. The outcomes can be maintained long term and many patients can return to their previous level of function.

References: Reference 1: Nerve Transfers: Indications, Techniques, and Outcomes Thomas H. Tung, Susan E. Mackinnon Journal of Hand Surgery - February 2010 (Vol. 35, Issue 2, Pages 332-341, DOI: 10.1016/j.jhsa.2009.12.002) Reference 2: Jonathan Isaacs, Treatment of Acute Peripheral Nerve Injuries: Current Concepts, The Journal of Hand Surgery, Volume 35, Issue 3, March 2010, Pages 491-497, ISSN 0363-5023, http://dx.doi.org/10.1016/j.jhsa.2009.12.009. Reference 3: Advances in nerve transfer surgery Amy M. Moore, Christine B. Novak Journal of Hand Therapy - 23 December 2013 (10.1016/j.jht.2013.12.007)

♦ No relevant financial relationships to disclose

E-poster 127: An Investigation of Late Stage Lateral Epicondylitits

Category: Basic Science Keyword: Elbow and Forearm Level 4 Evidence

♦ Danielle Stoll-Tronnes, MS ♦ Robert Harold Ablove, MD ♦ Owen J. Moy, MD ♦ Adam Zamzow, BS ♦ Jonathan Tueting, MD

Hypothesis: The purpose of this study was to investigate the various cells present at the origin of extensor carpi radialis brevis (ECRB) tendon in late chronic stages of lateral epicondylitis. We specifically investigated the presence of t-cells, indicating a late adaptive immune response.

Methods: Chronic ECRB tendon from the origin of eighteen patients (10 male and 8 female) were extracted via the standard Nirschl procedure and flash frozen. Specimens were sectioned and mounted on glass slides (5um thickness). Mouse and rabbit monoclonal antibodies were used to detect the cells of interest. Primary antibodies consisted of CD31, CD3, CD 163, CD 68 or PCNA (Abcam; Cambridge, MA). Light microscopy was used for spatial localization and cell counting of immunohistochemistry stains. Additional histological stains (hematoxylin and eosin) were used to qualitatively measure the density of cells in the lesion and the degree of collagen disorganization.

Results: Immunohistochemical analysis revealed hypervascularity and hyperproliferating cells in the lesions (consistent with previous findings).[1,2,3,4,5] In all specimens endothelial cells forming lumen to small vasculature were identified along with proliferating cells. In most specimens small quantities of CD68 and CD163 (macrophages I and II) were observed. The hematoxylin and eosin revealed a fair number of cells present in the specimens. CD-3 like immunoreactivity was noted suggesting presence of t-cells in the chronic tissue (figure 1). This presence of t-cells suggests that the adaptive immune system may partake in the late stages of lateral epicondylitis instead of the innate immune system. Disorganized collagen fibers were observed in all samples and were noted in areas of greater angiogenesis and cell proliferation (figure 2).

Summary Points: • Endothelial cells forming the lumen to newly created small vasculature and proliferating cells were present in chronic ECRB tendon indicating hypervascularity and hyperproliferating cells. • Small quantities of macrophages I and II were present and findings consist with existing studies.[6] • Collagen appeared to disorganized and unstructured in all collected tissue. • The role of the adaptive immune system has not been extensively explored in ECRB tendon. We investigated the presence of t-cell immunity and found it prevalent in all 18 samples. Further quantitative analysis will help compare the degree of tendinopathy to the presence of t-cells, and collagen arrangement. • In the future we wish to determine the t-cell phenotype, to help accurately infer their role in the disease process. T-helper 1, and t-helper 17 cells would be the primary analyzed phenotypes. Th17 is seen in other chronic degenerative inflammatory diseases.[7]

References: Reference 1: 1. Fedorczyk JM. Tennis elbow: blending basic science with clinical practice. J Hand Ther. 2006;19(2):146–153. Available at: http://www.ncbi.nlm.nih.gov/pubmed/16713862. Accessed July 8, 2011. Reference 2: 2. Ljung B-O, Alfredson H, Forsgren S. Neurokinin 1-receptors and sensory neuropeptides in tendon insertions at the medial and lateral epicondyles of the humerus. Studies on tennis elbow and medial epicondylalgia. J. Orthop. Res. 2004;22(2):321–327. Available at: http://www.ncbi.nlm.nih.gov/pubmed/15013091. Accessed July 8, 2011. Reference 3: 3. De Smedt T, de Jong A, Van Leemput W, Lieven D, Van Glabbeek F. Lateral epicondylitis in tennis: update on aetiology, biomechanics and treatment. Br J Sports Med. 2007;41(11):816–819. Available at: http://www.ncbi.nlm.nih.gov/pubmed/17616547. Accessed July 8, 2011. Reference 4: 4. Zeisig E, Ohberg L, Alfredson H. Extensor origin vascularity related to pain in patients with Tennis elbow. Knee Surg Sports Traumatol Arthrosc. 2006;14(7):659–663. Available at: http://www.ncbi.nlm.nih.gov/pubmed/16555106. Accessed July 8, 2011. Reference 5: 5. Ljung BO, Forsgren S, Fridén J. Substance P and calcitonin gene-related peptide expression at the extensor carpi radialis brevis muscle origin: implications for the etiology of tennis elbow. J. Orthop. Res. 1999;17(4):554–559. Available at: http://www.ncbi.nlm.nih.gov/pubmed/10459762. Accessed July 8, 2011. Reference 6: 6. Nirschl RP, Pettrone FA. Tennis elbow. The surgical treatment of lateral epicondylitis. J Bone Joint Surg Am. 1979;61(6A):832–839. Reference 7: 7. Alfredson H, Ljung BO, Thorsen K, Lorentzon R. In vivo investigation of ECRB tendons with microdialysis technique--no signs of inflammation but high amounts of glutamate in tennis elbow. Acta Orthop Scand. 2000;71(5):475–479. Available at: http://www.ncbi.nlm.nih.gov/pubmed/11186404. Accessed July 8, 2011.

♦ No relevant financial relationships to disclose E-poster 128: Changes in Wrist Motion after Scapholunate Arthrodesis: A Cadaveric Study

Category: Treatment, Surgical Technique, Anatomy Keyword: Hand and Wrist N/A - Not a clinical study

♦ Kevin D Han, MD ♦ Jaehon M Kim, MD ♦ Michael V Defazio, MD ♦ Ryan Katz, MD ♦ Kenneth R. Means, MD

Hypothesis: Scapholunate (SL) instability presents a relatively common, yet challenging, problem for the hand surgeon. A high incidence of nonunion and relatively poor outcomes with prior fixation techniques have precluded the widespread acceptance of SL arthrodesis for the management of acute or chronic instability of the SL joint. The purpose of this cadaveric study was to determine how SL fusion, if able to be achieved more reliably with modern fixation techniques, would affect wrist motion.

Methods: Ten cadaveric wrists were tested using a wrist joint range of motion simulator. Manual and fluoroscopic examination of all wrists were performed prior to ensure an absence of underlying carpal pathology. Flexor and extensor tendons were exposed and sutured to standard five-pound weights to simulate wrist range of motion at maximum extension (ECRL/ECRB/ECU), flexion (FCR/FCU), radial deviation (ECRL/FCR), ulnar deviation (ECU/FCU), dart thrower’s extension (ECRL/ECRB), and dart thrower’s flexion (FCU) (Figure 1A). A dorsal-radial incision was created to permit insertion of two 3.0 mm headless compression screws across the SL joint to simulate fusion (Figure 1B). Goniometric measurements and fluoroscopic images were obtained for each range of motion both before and after simulated SL fusion. The paired t-test was used to compare wrist motion before and after arthrodesis.

Results: Appropriately positioned and rigid simulated SL fusion was verified under fluoroscope and a consistent SL angle (470 + 60 vs. 460 + 40, p=0.37; pre and post fusion, respectively) was ensured (Figure 1B). The SL angle did not change throughout range of motion testing after screw insertion, confirming simulation of rigid SL fusion. The only statistically significant decreases in wrist range of motion following simulated SL fusion occurred during maximum flexion, dart thrower’s extension, and dart thrower’s flexion. Wrist flexion decreased 9 d on average following SL fusion. Additionally, dart thrower’s extension and flexion decreased an average of 9 d and 6 d, respectively, compared to the non-fused wrist (Table 1).

Summary Points: • SL arthrodesis has been attempted in the past but with varied success, perhaps due to fixation techniques available at the time. • We have established in a cadaveric model the effect of simulated SL fusion on radiocarpal and midcarpal motion, which compares favorably to reported range of motion outcomes for previous SL repair or reconstruction procedures. • The statistically significant decreases in wrist flexion and dart thrower’s extension and flexion following simulated SL fusion are of questionable clinical significance given the relatively small effect size.

♦ No relevant financial relationships to disclose

E-poster 129: How Close to the Anterior Interosseous Nerve Are Sutures Passed Through The Anterior Capsule of the Elbow To Stabilize The Coronoid?

Category: Surgical Technique, Anatomy Keyword: Elbow and Forearm Level 4 Evidence

♦ Susanne M Roberts, MD ♦ Aidin Masoudi, MD ♦ Brandon E Earp, MD ♦ George S M. Dyer, MD

Hypothesis: When the anterior capsular attachment to the coronoid is avulsed or fractured off in an elbow fracture-dislocation, suture repair is a valuable technique to restore stability. A suture is placed through the anterior capsule, passed through a coronoid fragment if present, and either secured to a suture anchor or passed through bone tunnels and tied over the dorsal ulna. Although seldom discussed in the literature, we suspect this stitch is disquietingly close to the anterior interosseous nerve (AIN). This study aims to define how close it is.

Methods: 20 fresh frozen cadaver specimens were used to create a lateral approach to the elbow (Table 1). Radial heads were removed and a type II coronoid fracture was created with an osteotome. A lasso suture was passed through the anterior capsule around the coronoid. The median nerve and AIN were then dissected from the antecubital fossa to mid forearm. A marker was placed at the division of the median nerve and AIN and a digital caliper was then used to measure the distance from the capsular stitch to the marker with the forearm in neutral rotation (Figure 1).

Results: The average distance from the capsular stitch to the AIN was measured to be 4.94mm. The lowest distance was 3.43mm and the highest was 7.8mm. The average distance in men was 5.32cm and in women was 4.68cm.

Summary Points: - Suture repair of the anterior capsule to the coronoid is critical to restoring stability in many elbow fracture-dislocations. - The AIN is about 5mm from proper placement of this stitch and care must be taken to avoid injury to the nerve during this procedure.

References: Reference 1: Garrigues GE, Wray WH, 3rd, Lindenhovius AL, Ring DC, Ruch DS. Fixation of the coronoid process in elbow fracture-dislocations. The Journal of bone and joint surgery. American volume. 2011;93:1873-1881. Reference 2: McKee MD, Pugh DM, Wild LM, Schemitsch EH, King GJ. Standard surgical protocol to treat elbow dislocations with radial head and coronoid fractures. Surgical technique. The Journal of bone and joint surgery. American volume. 2005;87 Suppl 1:22-32. Reference 3: Mathew PK, Athwal GS, King GJ. Terrible triad injury of the elbow: current concepts. The Journal of the American Academy of Orthopaedic Surgeons. 2009;17:137-151.

♦ No relevant financial relationships to disclose

E-poster 130: Restricted Wrist Circumduction Impairs Functional Performance

Category: Evaluation/Diagnosis, Treatment, Therapy/Rehabilitation, Prognosis/Outcomes Keyword: Hand and Wrist, General Principles Level 4 Evidence

♦ Curtis M Henn, MD ♦ Aviva Wolff, OTR, CHT ♦ Lilly Tran, BS ♦ Mandi Gibbons, BS ♦ Andrew Kraszewski, M.S ♦ Scott W Wolfe, MD

Hypothesis: Wrist circumduction represents the maximum envelope of wrist motion and has shown recent promise as a correlate to wrist function. (1) The goal of the current study is to utilize non- invasive 3D motion analysis to measure coupled wrist motion during performance of wrist- specific functional tasks. We hypothesize that decreased 3D wrist motion will be associated with decreased performance during wrist-specific tasks.

Methods: Ten healthy subjects were recruited to perform wrist-specific functional tasks in three conditions: 1) free, 2) a partially restrictive foam splint, and 3) a severely restrictive hinged splint. Each task was performed while seated at a desktop with the elbow and forearm immobilized and while standing with the elbow and forearm unrestricted. 3D motion analysis was performed using 29 reflective markers and a twelve-camera motion capture system. (2) Circumduction was described as the circumscribed area of motion, the circumference (kinematic path length) and orientation of the major axis (coupling axis). These parameters were recorded during maximal circumduction and during three functional tasks: dart throwing, hammering, and winding of thread around a spool.

Results: 3D motion analysis and performance data for the first five subjects are summarized in Figure 1 and Table 1. Circumduction area and kinematic path length (KPL) decreased sequentially with more restrictive splints. KPL showed a similar stepwise decline during both dart throwing and hammering, particularly with the elbow and forearm restricted. The coupling axis was consistent across all conditions tested. Dart throwing performance was similar between free and foam splint conditions with the elbow restricted but decreased in the hinged splint. A similar stepwise decline in function was observed with the elbow free and was most evident between the free and foam splinted conditions. Performance on the winding task remained similar between the free and foam splint conditions and decreased in the hinged splint. Interestingly, performance on the hammering task remained similar among all three conditions whether the elbow was restricted or unrestricted.

Summary Points: We have demonstrated that 3D motion analysis can be utilized in vivo to objectively measure changes in complex coupled wrist motion. Functional performance is maintained through small decreases in wrist circumduction but declines with further decreases in circumduction area and KPL. Coupled motion parameters may be better candidates than traditional measures of wrist motion for assessment of wrist functional ability, though the relationship between these parameters and wrist function may not be linear.

References: Reference 1: Franko OI, Zurakowski D, Day CS. Functional disability of the wrist: direct correlation with decreased wrist motion. J Hand Surg Am 2008 Apr;33(4):485-92. Reference 2: Wolfe SW, Garg R, Kraszewski A, Backus S, Mogekwu N, Lenhoff M, Wolff A, Crisco JJ, Hillstrom H. Comparison of Wrist Kinematics and Functional Performance between Surgical Treatments for SLAC Wrist. 66th Annual Meeting, American Society for Surgery of the Hand, Las Vegas Sept. 9, 2011

♦ No relevant financial relationships to disclose

E-poster 131: Elimination of Motoneurons Produces a Permanent, Incomplete Nerve Injury Model

Category: Basic Science Keyword: Nerve N/A - Not a clinical study

♦ Louis Poppler, MD ♦ Matthew Wood, PhD ♦ Dan Hunter, RA ♦ Susan E Mackinnon, MD ♦ Amy Moore, MD

Hypothesis: The goal of this study was to develop an incomplete, non-regenerative nerve injury model that results in permanently reduced muscle force and allows the study of therapeutics to improve motor function. We hypothesized that transection of one or more of the L4-6 nerve roots would reduce motoneuron counts to less than 20% of normal values, a level shown to cause a measurable reduction in muscle force.

Methods: Eighty rats were randomized into four groups (n=20) that underwent variations of nerve root transections. Group I and II had the L4 or L5 nerve root transected respectively, and a silicone cap placed proximally to prevent regeneration. Group III had both L4 and L5 roots and group IV had the L4 and L6 roots transected and capped. Retrograde labeling of the tibial and peroneal nerves (n=12 per group) was performed at 3 weeks. Normal values were established in a sham surgery group. Tibial and peroneal nerves were harvested for histomorphometry at 3 and 12 weeks to evaluate the presence of myelinated axons. Muscle force testing (n=8 per group) is underway to provide functional data corroborating the reduced counts. Neurman-Keuls post-hoc analysis was performed.

Results: The tibial and peroneal motoneuron counts in all experimental groups were significantly reduced in comparison to uninjured controls (Figure 1). In the control group, the tibial nerve mean motoneuron count was 2121 ± 214 and the peroneal nerve was 1733 ± 74. In group I (L4-cut), the tibial mean motoneuron count was 38% of the control (798 ± 94) and the peroneal was 20% (328 ± 186). In group II (L5-cut), the tibial mean motoneuron count was 33% of control (705 ± 170) and peroneal was 25% (432 ± 91). In group III (L4&5-cut), the tibial mean motoneuron count was 6% of control (131 ± 43) and the peroneal had no motoneurons. In group IV (L4&6- cut), the tibial mean motoneuron count was 20% of control (431 ± 89) and the peroneal was 8% (133 ± 40). Histomorphometry (Figure 2) and preliminary muscle force data support sustained reduction of myelinated axon counts and reduced muscle force.

Summary Points: • Transection of L4 and L6 produces a permanent reduction in motoneurons and myelinated axons resulting in a reproducible and stable decrease in muscle force. • Unlike previously described partial nerve injury models, this novel model avoids the rat’s innate neuroregenerative capability and produces a stable platform from which to evaluate therapeutics to increase motor function.

References: Reference 1: T. Gordon, J. F. Yang, K. Ayer, R. B. Stein, and N. Tyreman, 'Recovery Potential of Muscle after Partial Denervation: A Comparison between Rats and Humans', Brain Research Bulletin, 30 (1993), 477-82. Reference 2: Terence M. Myckatyn, and Susan E. MacKinnon, 'A Review of Research Endeavors to Optimize Peripheral Nerve Reconstruction', Neurological Research, 26 (2004), 124-38. Reference 3: T. S. Malushte, J. M. Kerns, C. C. Huang, S. Shott, J. Safanda, and M. Gonzalez, 'Assessment of Recovery Following a Novel Partial Nerve Lesion in a Rat Model', Muscle Nerve, 30 (2004), 609-17. Reference 4: Jonathan Isaacs, Satya Mallu, Yan Wo, and Sagar Shah, 'A Rodent Model of Partial Muscle Re-Innervation', Journal of Neuroscience Methods, 219 (2013), 183-87. Reference 5: J. D. Alant, F. Senjaya, A. Ivanovic, J. Forden, A. Shakhbazau, and R. Midha, 'The Impact of Motor Axon Misdirection and Attrition on Behavioral Deficit Following Experimental Nerve Injuries', PLoS One, 8 (2013), e82546.

♦ No relevant financial relationships to disclose

E-poster 132: An Operatorless Method for Determining Resident Competency in Orthopedic Procedures

Category: Surgical Technique, Medical/Legal Keyword: Elbow and Forearm Level 4 Evidence

♦ Susanne M. Roberts, MD ♦ Aidin Masoudi, MD ♦ Brandon E. Earp, MD ♦ George S. M. Dyer, MD

Hypothesis: In the face of work hour restrictions and concerns for patient safety resident surgical experience has suffered. As a result, there is growing interest in surgical simulation for acquisition and testing of surgical skills. Testing in particular is often time consuming for attending physicians and requires their expertise. In this study we hypothesize that an operatorless method can determine resident competency in a basic procedure such as lateral entry pin fixation of the distal humerus.

Methods: Twelve postgraduate year (PGY) one through five residents were asked to perform lateral entry pin fixation on a cadaveric distal humerus. Resident total task time, drill running time, and number of radiographs taken were recorded. Drill running time was obtained by attaching an iphone recorder to the drill. Final anteroposterior and lateral radiographs were obtained and a grading scale applied. Radiographs were given grade one through five based on how many goals of the procedure were completed; one lateral column pin placed, on medial column pin placed, bicortical fixation achieved, anterior to posterior pin placement, adequate pin separation (Figure 1).

Results: There was a positive correlation between postgraduate year and grade (0.696). All other variables, total task time (-0.576), drill running time (-0.203), and number of images taken (- 0.413) had a negative correlation with postgraduate year (Table 1).

Summary Points: - In this study postgraduate year is used as a proxy for resident surgical experience. As expected, increasing postgraduate year corresponds with increasing competency in meeting the radiographic goals of the procedure (Chart 1). - Additionally, increasing postgraduate year corresponds with increased efficiency in performing the procedure as evidenced by decreased total and drill running time as well as decreased number of images taken (Chart 2). - Our results show that assessment of resident competency in basic orthopedic procedures can be achieved in an operatorless system. No technician is required to record time and radiograph number, and a simple grading scale can be applied to radiographic assessment without necessary expertise. - Methods such as this can help to mitigate the tension between acquisition and testing of resident surgical skills and the demands on attending physician time and expertise.

References: Reference 1: Kocher MS, Kasser JR, Waters PM, Bae D, Snyder BD, Hresko MT, Hedequist D, Karlin L, Kim YJ, Murray MM, Millis MB, Emans JB, Dichtel L, Matheney T, Lee BM. Lateral entry compared with medial and lateral entry pin fixation for completely displaced supracondylar humeral fractures in children. A randomized clinical trial. The Journal of bone and joint surgery. American volume. 2007;89:706-712. Reference 2: Sankar WN, Hebela NM, Skaggs DL, Flynn JM. Loss of pin fixation in displaced supracondylar humeral fractures in children: causes and prevention. The Journal of bone and joint surgery. American volume. 2007;89:713-717. Reference 3: Skaggs DL, Cluck MW, Mostofi A, Flynn JM, Kay RM. Lateral-entry pin fixation in the management of supracondylar fractures in children. The Journal of bone and joint surgery. American volume. 2004;86-A:702-707.

♦ No relevant financial relationships to disclose

E-poster 133: Surgical treatment for the thumb swan neck deformity in rheumatoid arthritis

Category: Treatment, Surgical Technique Keyword: Hand and Wrist Level 4 Evidence

♦ Takuji Iwamoto, MD, PhD ♦ Taku Suzuki, MD, PhD ♦ Noboru Matsumura, MD, PhD ♦ Kazuki Sato, MD, PhD ♦ Yoshiaki Toyama, MD, PhD ♦ Toshiyasu Nakamura, MD, PhD

Hypothesis: The swan neck (Nalebuff type III) deformity results from radial subluxation of the CMC joint following MCP joint hyperextension and IP joint flexion. The purpose of this study is to assess the surgical outcomes for the thumb swan neck deformity by CMC joint resection arthroplasty with or without the volar restraint of MCP joint hyperextension.

Methods: Twelve thumbs in 12 RA patients were included in this study. The mean age at the time of the procedure was 69 years (range 54-83 years), and the mean follow-up was 21 months (range 10- 42 months). The preoperative deformities were classified into moderate 6 and severe 6 according to the system described by Nalebuff. The resection arthroplasty with ligament reconstruction for CMC joint was performed for all cases, and dorsal capsular release for MCP joint was performed for 6 severe cases. In 5 cases (moderate 2, severe 3; group1), volar plate reattachment for the hyperextended MCP joint was indicated, and the procedure was not indicated in the other 7 cases (moderate 4, severe 3; group2). Clinical examination included an evaluation of the ROM of the thumb, the ability of thumb opposition (Kapandji classification), and the patients’ satisfaction using visual analog scale (VAS: score 0 indicated dissatisfaction, and 100 indicated completely satisfaction).

Results: The mean CMC joint ROM significantly increased from 5° to 25° in radial abduction, and from 25° to 37° in palmar abduction. Although MCP joint hyperextension was improved from 47° to 16°, the tendency of hyperextension was remained 5 cases in group2. Tendon adhesion of flexor pollicis longus occurred 2 cases in group1. Thumb appearance improved in 10 cases, and mean VAS for the satisfaction was 76. Summary Points: CMC joint arthroplasty was useful for the thumb swan neck deformity. Volar restraint of MCP joint was required to prevent hyperextension.

♦ No relevant financial relationships to disclose

E-poster 134: Glenohumeral Extension in Children with Brachial Plexus Birth Palsy: An Important Factor for Reaching Behind the Back

Category: Evaluation/Diagnosis, Prognosis/Outcomes Keyword: Shoulder and Arm, Congenital and Pediatric Problems Level 2 Evidence

♦ Stephanie A.Russo, BS ♦ Kristen F. Nicholson, BS ♦ Scott H. Kozin, MD ♦ Dan A. Zlotolow, MD ♦ James G. Richards, PhD

Hypothesis: In children with brachial plexus birth palsy (BPBP), the hand to spine Mallet position has traditionally been considered a measure of internal rotation; however, difficulty executing this task in the presence of adequate internal rotation suggests that additional factors are associated with performing this movement. We hypothesized that glenohumeral extension is significantly greater in children with a hand to spine Mallet score of three or higher, that the glenohumeral extension angle in the hand to spine position represents maximal glenohumeral extension, and that the hand to spine Mallet score correlates with both the internal rotation modified Mallet score and glenohumeral extension angle in the hand to spine position.

Methods: Thirty-two patients with BPBP were recruited for this study. Modified Mallet scores were determined by a pediatric hand surgeon. A three-dimensional motion capture system (Motion Analysis Corporation, Santa Rosa, CA) was used to capture the location of markers placed on the thorax, humerus and scapula (Figure 1) in the hand to spine Mallet position and maximal humerothoracic extension in the sagittal plane. Glenohumeral extension was compared between children with Mallet scores of three or higher and two or lower using an independent t-test and compared between the hand to spine position and maximal extension using a dependent t-test. Correlations between hand to spine and internal rotation modified Mallet scores and hand to spine score and glenohumeral extension angle were assessed using Pearson’s correlation.

Results: Children with higher hand to spine scores demonstrated significantly (p = 0.005) larger glenohumeral extension angles (17.8° vs. -2.3°). Glenohumeral extension was significantly (p < 0.001) larger in the hand to spine position (3.8°) than maximal extension in the sagittal plane (- 8.2°). Hand to spine and internal rotation modified Mallet scores correlated significantly (p = 0.007, Pearson’s r = 0.469). However, of the 13 participants with internal rotation scores of four, hand to spine scores ranged from two (n = 7) to four (n = 4). Additionally, the glenohumeral extension angle significantly (p = 0.021) correlated with the hand to spine score (Pearson’s r = 0.407).

Summary Points: • The ability to successfully reach behind one’s back requires both sufficient internal rotation and glenohumeral extension. • Children utilize their maximal glenohumeral extension capacities when attempting to reach behind their backs, regardless of whether they successfully achieved the position. • Hand to spine performance does not consistently measure internal rotation ability due to the need for both internal rotation and extension to execute this task.

References: Reference 1: Bae, DS, et al. (2003) J Bone Joint Surg, 85-A(9): 1733-38. Reference 2: Abzug, JA, et al. (2010) J Pediatr Orthop, 30: 469-74. Reference 3: Kozin, SH, et al. (2010) J Shoulder Elbow Surg, 19: 102-10. Reference 4: Russo, SA, et al. (2014) J Shoulder Elbow Surg, 23: 327-38. Reference 5: Mehlman, CT, et al. (2011) J Pediatr Orthop, 31: 341-51.

Figure 1. Markers on the trigonum spinae (root of the scapular spine) and inferior angle were placed while participants held each position.

♦ No relevant financial relationships to disclose

E-poster 135: A Comparison of Barbed Suture Versus Traditional Techniques for Muscle Belly Repair

Category: Surgical Technique Keyword: General Principles N/A - Not a clinical study

♦ Manoucher L Tavana, MD ♦ Kanu S Goyal, MD ♦ Robert J Goitz, MD

Hypothesis: The use of barbed sutures in wound closure and tendon repair have been compared with mixed results over traditional suture material, however muscle belly repair specifically has not been previously examined. This study examines the use of barbed suture when used in muscle belly repair in a custom configuration by comparing it to traditional Mason-Allen, Modified Kessler and Figure of Eight configurations as well as a control configuration similar to that used with the barbed suture.

Methods: Twenty-five matched porcine psoas muscles were assigned to repair by 5 different test groups - Mason-Allen with #1 Ethibond, Figure of Eight Allen with #1 Ethibond, Modified Kessler with #1 Ethibond, Custom Configuration with #2 Barbed PDO, Custom Configuration with #1 Ethibond. The repair was performed on the cut edge of muscle, with the free end of the suture anchored to a fixed base, forming a singe sided repair. An Instron 8874 tensometer was used to linearly distract the repair to failure at 1mm/s after after 1N preload. 5 samples of each group were run, with load to failure and distraction at 10N compared.

Results: Muscle repair with barbed suture in a custom configuration had a statistically significantly greater load to failure than all other methods of muscle repair (p< 0.01). It also showed statistically significant less displacement at 10N of force than all other methods of repair (p<0.01) except the Mason-Allen repair with #1 Ethibond (p=0.34). Mode of failure for traditional techniques was suture pull-through with tissue loss while failure with barbed suture was through suture pull-out without tissue loss. Displacement at 10N (cm) Load at Failure (N) Custom, Barbed 1.57 ± 0.39 17.86 ± 2.26 Custom, #1 Ethibond 3.55 ± 0.78 13.16 ± 1.57 Figure of 8, #1 Ethibond NA** 8.96 ± 4.24 Mason-Allen, #1 Ethibond 1.84 ± 0.39 12.73 ± 2.40 Kessler, #1 Ethibond NA* 7.71 ± 3.78 **three of five specimens failed before 10N of load, *four of five specimens failed before 10N of load.

Summary Points: Barbed suture provides a mechanism for evenly distributing force across the entire suture, as opposed to having single points of tension with traditional suture. Because of the friable nature of muscle tissue in suture pull-through, barbed suture would seem to be the preferred choice for repair. This study shows that in muscle repair barbed suture increases overall load to failure as well as decreasing displacement at 10N of force. Further investigation is warranted.

References: Reference 1: Biomechanical analysis of knotless flexor tendon repair using large-diameter unidirection barbed suture. Lin TE, Lakhiani C, Lee MR, Saint-Cyr M, Sammer DM. Hand (N Y). 2013 Sep;8(3):315-9 Reference 2: Flexor tendon repair with barbed suture: an experimental study. Sato M, Matsumura H, Gondo M, Shimada K, Watanabe K. Eur J Orthop Surg Traumatol. 2013 Oct 12. Reference 3: A comparison between barbed and nonbarbed absorbable suture for fascial closure in a porcine model. Oni G, Brown SA, Kenkel JM. Plast Reconstr Surg. 2012 Oct;130(4):535e- 540e. Reference 4: A knotless flexor tendon repair technique using a bidirectional barbed suture: an ex vivo comparison of three methods. McClellan WT, Schessler MJ, Ruch DS, Levin LS, Goldner RD. Plast Reconstr Surg. 2011 Oct;128(4):322e-327e Reference 5: Flexor tendon repair with a knotless barbed suture: a comparative biomechanical study. Marrero-Amadeo IC, Chauhan A,

♦ No relevant financial relationships to disclose

E-poster 136: Pseudo-Target Sign’: A Characteristic MR Finding for Preoperative Diagnosis of Vascular Leiomyoma in the Hand.

Category: Evaluation/Diagnosis Keyword: Diseases and Disorders Level 4 Evidence

♦ Kazuki Kuniyoshi, MD, PhD ♦ Tomoyuki Rokkaku, MD

Hypothesis: Vascular leiomyoma in the hand is a comparatively rare soft tissue tumor, which is reported sporadically in the literature. We reviewed magnetic resonance images (MRI) from 24 cases of vascular leiomyoma. A unique finding resembling the ‘target sign’ of neurilemmoma, which has not been reported previously was designated as ‘pseudo- target sign’.

Methods: Patients (n = 24, 15 males, mean age 57 years, range; 27- 77 years), received MR imaging with T1- and T2-weighted images in least in 2 planes, coronal or sagittal and axial views acquired on a 1.5 Tesla scanner. After imaging, tumors were removed surgically and the diagnosis of vascular leiomyoma was confirmed by pathology. Tumors were classified further into 3 sub-types according to Morimoto’s classification as capillary, venous or cavernous. Correlation of pathology and MR findings was evaluated retrospectively.

Results: In all cases, the signal intensity on T1 weighted images was equal to the muscle and also flat inside the tumor. In 19 of 24 cases, T2-weighted images showed a unique contrast of high and low intensity (heterogeneous intensity pattern), which resembled the target sign of neurilemmoma, but was considerably higher in leiomyoma than in neurilemmoma as to high lesion inside. In the remaining five, T2-weighted images indicated a flat and very high lesion (homogeneous intensity pattern) as is commonly seen with vascular tumors. Of the 19 cases with this finding on T2-weighted images, 7 cases were capillary, 5 were venous and 7 were cavernous sub-type. Of the cases with the homogeneous intensity pattern, 2 were capillary, 1 was venous and 2 were cavernous sub-type. There was no correlation between T2-weighted intensity pattern and histological sub-type.

Summary Points: The high and low intensity areas on T2-weighted images are thought to represent vessels filled with blood and smooth muscle respectively. This unique mixture of a high and low intensity pattern is due to the location and the proportion of vessels and muscles within the tumor. It may be possible to diagnose vascular leiomyoma preoperatively with this MR finding of ‘pseudo target sign’.

♦ No relevant financial relationships to disclose

E-poster 137: Long Term Outcomes of Congenital Hand Reconstruction Using Free Toe Phalanx Transfer

Category: Treatment, Surgical Technique Keyword: Hand and Wrist Level 4 Evidence

♦ William H Seitz, Jr., MD ♦ Noah Matthew Raizman, MD ♦ Adam Meisel, MD ♦ Bryan Naelitz, Student

Hypothesis: A report of pain & dissatisfaction in foot function in children having undergone free toe phalanx transfer as part of the reconstruction process for congenital hand difference has been recently reported. Having performed over 200 such procedures over 28 years, the authors have not appreciated this complication. We hypothesized using our technique of a dorsal approach with extensor tendon splitting, extraperiosteal sharp dissection, careful flexor tendon preservation and extensor tendon repair, there is little, if any morbidity or functional impairment following free toe phalanx transfer.

Methods: Records were reviewed to find children who had undergone free, extra periosteal toe phalanx transfer to the hand with subsequent callotasis lengthening. Their underlying diagnosis was recorded including all associated procedures and any complications. We then attempted to evaluate all patients by personal examination and/or contact their families for inclusion in the study. Informed consent of the patient or parents/legal guardians and the assent of the patients themselves was required for inclusion in the study, which was reviewed and approved by our Institutional Review Board. 44 patients or their parents with multiple toe phalanx transfers at least two years post surgery were administered the Osford Ankle Foot Questionnaire for Children (OXAFQ-C)as appropriate, as well as the Foot and Ankle Ability Measure (FAAM), both well-validated lower extremity functional outcome instruments. The patients families were also asked whether they were satisfied with the overall outcome of the surgical treatment,would they undergo the same trament again, whether the upper extremity outcome justified the lower extreme morbidity (if any), and would they recommend the same surgical treatment to another child/family with a similar condition. All date was collected and analyzed by independent observers who had not participated in the care of the patients.

Results: Almost universally, pain, function, activities, sports, footwear, were rated extremely highly (<1.0) Satisfaction in all areas was high (1.0), the only sense of mild dissatisfaction was in appearance (3.4), and having others at some time being unkind (4.2). Every patient / family (44/44) said they would go through the surgery again and would recommend it to others.

Summary Points: Free toe Phalangeal transfer using the 2nd& 3rd toes of one or both feet can provide needed functional bone stock to congenitally hypoplastic digits as part of the reconstruction process. When performed carefully using a dorsal, extraperiosteal approach with protection / preservation of the flexor tendon minimal foot complications and a high satisfaction rate can be expected.

♦ No relevant financial relationships to disclose

E-poster 138: Clinical and radiological outcomes of scaphoidectomy and 4-corner fusion in scapholunate advanced collapse at 5 and 10 years.

Category: Treatment, Prognosis/Outcomes Keyword: Hand and Wrist, Diseases and Disorders Level 4 Evidence

♦ Soo Min Cha, MD ♦ Hyun Dae Shin, MD, PhD

Hypothesis: Partial wrist arthrodesis is commonly performed to treat wrist arthritis because it provides pain relief without sacrificing complete wrist motion. The purposes of this retrospective study were to evaluate clinical and radiological outcomes after scaphoidectomy and 4-corner fusion after more than 10 years of follow-up and to compare the midterm and long-term results.

Methods: Forty-two patients were enrolled. The following were evaluated annually: pain (visual analog scale); Disabilities of the Arm, Shoulder, and Hand score; range of motion; grip strength; and Modified Mayo Wrist score. Bony union and arthritic changes in the radiolunate joint were also evaluated radiologically. Midterm and long-term results were compared.

Results: The mean (SD) follow-up period was 12.2 (1.43) years. Two patients were excluded from the study because of complications, so the final postoperative evaluation included 40 patients. Visual analog scale and Disabilities of the Arm, Shoulder, and Hand scores improved to a satisfactory level by 5 years after surgery and did not differ significantly between 5 and 10 years. Flexion, extension, and radial deviation were reduced after 5 years compared with preoperative measures, and no difference was found between 5 and 10 years. Ulnar deviation, pronation, and supination did not change significantly after surgery. Grip strength was significantly recovered from 29.7 (4.9) kg at 5 years after surgery to 32.1 (8.5) kg at 10 years. The Modified Mayo Wrist score improved significantly to 83.2 (4.1) at 5 years after surgery but did not differ significantly between 5 and 10 years. All cases showed radiological solid fusion, and the mean (SD) period of union was 9.34 (3.7) weeks. Further radiolunate arthritic change was verified in 2 patients, but Modified Mayo Wrist scores were fair. One patient experienced inexplicable pain; therefore, total wrist fusion was performed at 6 years after surgery.

Summary Points: This retrospective cohort study of patients followed up for more than 10 years showed that the midterm and long-term results of 4-corner fusion for stage III SLAC were satisfactory, and arthritic changes in the radiolunate joint were minimal.

References: Reference 1: Krakauer JD, Bishop AT, Cooney WP. Surgical treatment of scapholunate advanced collapse. J Hand Surg Am. 1994;19:751Y759. Reference 2: Siegel JM, Ruby LK. Midcarpal arthrodesis. J Hand Surg Am. 1996;21:179Y182. Reference 3: Vance MC, Hernandez JD, Didonna ML, et al. Complication and outcome of four- corner arthrodesis: circular plate fixation versus traditional techniques. J Hand Surg Am. 2005;30:1122Y1127. Reference 4: Ashmead D, Watson K, Damon C, et al. Scapholunate advanced collapse wrist salvage. J Hand Surg Am. 1994;19:741Y750.

♦ No relevant financial relationships to disclose

E-poster 139: Outcomes of Revision Distal Biceps Repair

Category: Treatment, Surgical Technique, Prognosis/Outcomes Keyword: Elbow and Forearm, Shoulder and Arm, Diseases and Disorders Level 3 Evidence

♦ Vanessa C. Prokuski, MD

Hypothesis: We hypothesize that revision of distal biceps tendon repairs will yield results comparable to primary distal biceps tendon repairs.

Methods: We retrospectively reviewed the charts of eight patients whose primary distal biceps tendon re- attachment failed following a postoperative traumatic event. Two of the eight patients had their initial surgery done elsewhere. Six of the eight had their initial and revision surgery performed by the same surgeon. The same surgeon performed 312 primary distal biceps re-attachments during the same time period. The eight patients were revised with a trans-osseous technique. Demographic information, details about the primary and secondary injuries and repairs, time between injuries and repairs, operative findings, and outcomes were recorded.

Results: The patients were all male with an average age of 45. Failure of the original fixation was recognized at a mean of 3 months (range 1 week-6 months). Failure occurred either because of failure of distal fixation or failure of the suture weave. Revision surgery was performed at a mean of 11 months (range 4-24 months) from the date of the primary re-attachment. Four of the eight repairs were augmented with allograft. One patient had nerve symptoms that resolved with a neurolysis. The incidence of re-rupture was 1.9% when performed by the same surgeon with the same technique. All the patients returned to their former occupation and were satisfied with their outcome. The re-attached distal biceps tendon was palpably present with the hook test. Average elbow flexion was 143 degrees (range 135-145) and elbow extension was 0.62 degrees (range 0-5). Average forearm pronation was 69.4 degrees (range 65-70). Average forearm supination was 81.9 degrees (range 60-85).

Summary Points: *Re-rupture of a re-attached distal biceps tendon occurs rarely. *Re-rupture occurs because of failure of the distal fixation or the proximal suture weave. *Re-attachment of a previously failed repair may require augmentation with an allograft, but the results are comparable to the expected outcomes from an uncomplicated primary repair.

♦ No relevant financial relationships to disclose

E-poster 140: Minimally Invasive High Resolution Ultrasound Guided Trigger Finger Release: A blinded prospective follow up study

Category: Treatment, Prognosis/Outcomes, Billing/Coding Keyword: Hand and Wrist Level 4 Evidence

♦ Brian Jurbala, MD

Hypothesis: We hypothesized that office based minimally invasive, ultrasound guided trigger finger release would result in equal patient satisfaction rates and lower overall costs compared to the same procedure performed in the operating room.

Methods: This 2 part study was conducted after obtaining IRB approval. In the first part of the study we retrospectively reviewed the records of 68 consecutive patients with 95 trigger fingers that underwent minimally invasive A-1 Pulley release by a single surgeon utilizing a distal to proximal technique with a sonographically enhanced knife and High Resolution Ultrasound guidance. In the chart review we noted location of procedure (office vs operating room), length of follow up, presence of absence of residual triggering and evidence of any post-operative complications. We compared overall costs of the procedure in both the operating room and office based on 2013 Medicare reimbursement rates. In the second part of the study, a blinded follow up examiner was used to perform a follow up examination and administer a follow up questionnaire. The examiner attempted to contact each participant in the first part of the study for a follow up examination and to fill out a survey regarding their satisfaction with the surgical treatment they received for their trigger finger. Patients that responded to the request but could not physically come into the office for an examination completed satisfaction questionnaire by mail, email or over the phone.

Results: All patients had absence of triggering on follow-up examination. There were no neurovascular complications or tendon injuries. One patient noted recurrence of pain and a slight click that resolved with a single steroid injection. 22 of the 68 patients in the first part of the study responded to the request for follow up. Of the 22 that responded, 9 came in for a physical examination and to fill out the satisfaction survey and 13 completed the survey only (by, phone, email or mail). 19 of 22 patients rated their satisfaction as excellent, 3 of 22 as satisfied and no patients were unsatisfied. Overall cost of the procedure was 36% less when the procedure was performed in the office when compared to ASC.

Summary Points:

Minimally invasive high resolution ultrasound guided trigger finger release resulted in equally high patient satisfaction rates in both the operating room and office. There was significant overall cost savings when the procedure was performed in the office as compared to the operating room.

♦ No relevant financial relationships to disclose

E-poster 141: Demineralized Bone Matrix Insertion in the Metaphyseal Defect of Comminuted Distal Radius Fractures during Volar Plating.

Category: Surgical Technique, Prognosis/Outcomes Keyword: Hand and Wrist Level 2 Evidence

♦ Jae-Hwi Nho, MD ♦ Tae-Kyung Lee, MD ♦ Byung Sung Kim, Md,PhD ♦ Hong Kee Yoon, MD ♦ In-Woo Byun, MD ♦ Hyun Sik Gong, MD

Hypothesis: In comminuted distal radius fractures(DRF), various bone graft substitutes has been introduced to improve stability after volar plating. Among them, we aimed to determine whether filling with demineralized bone matrix(DBM) in the metaphyseal defect of the comminuted DRF(AO type 23- C2 or C3) during volar plating, affects radiologic and clinical outcomes.

Methods: We treated 60 patients older than 60 years old who had comminuted DRF with severe metaphyseal defect. Patients were randomized to either group A (30 patients), who received a volar plating only, or group B (30 patients) who received a volar plating with DBM insertion to fill metaphyseal defect additionally. We compared these two groups prospectively for radiologic and clinical outcomes at 12 weeks postoperatively. Complete union was considered by observing cortical continuity in all 4 different plain radiographs (wrist AP, lateral and both oblique view).

Results: There was no statistical significance between both groups in clinical outcomes including ROM, DASH score. However, there was significant difference in complete union rate in plain radiographs at 12 weeks postoperatively(Group A: 21/30, Group B: 28/30, p value<0.05).

Summary Points: DBM insertion in the metaphyseal defect of comminuted DRFs during volar plating could improve union rates and period without notable complications. DBM insertion can be an effective alternative to improve stability and to shorten union period of comminuted DRFs.

References: Reference 1: Abramo A, Geijer M, Kopylov P, Tagil M (2010) Osteotomy of distal radius fracture malunion using a fast remodeling bone substitute consisting of calcium sulphate and calcium phosphate. Journal of biomedical materials research. Part B, Applied biomaterials, 92(1):281-286 Reference 2: Capo JT, Hashem J, Orillaza NS, Tan V, Warburton M, Bonilla L (2010) Treatment of extra-articular distal radial malunions with an intramedullary implant. The Journal of hand surgery, 35(6):892-899 Reference 3: Cho HS, Seo SH, Park SH, Park JH, Shin DS, Park IH (2012) Minimal invasive surgery for unicameral bone cyst using demineralized bone matrix: a case series. BMC musculoskeletal disorders, 13:134 Reference 4: Handoll HH, Watts AC (2008) Bone grafts and bone substitutes for treating distal radial fractures in adults. The Cochrane database of systematic reviews(2):CD006836 Reference 5: Hegde C, Shetty V, Wasnik S, Ahammed I (2013) Use of bone graft substitute in the treatment for distal radius fractures in elderly. European journal of orthopaedic surgery & traumatology : orthopedie traumatologie, 23(6):651-656 Reference 6: Huber FX, Hillmeier J, Herzog L, McArthur N, Kock HJ, Meeder PJ (2006) Open reduction and palmar plate-osteosynthesis in combination with a nanocrystalline hydroxyapatite spacer in the treatment of comminuted fractures of the distal radius. J Hand Surg Br, 31(3):298- 303 Reference 7: Jakubietz MG, Gruenert JG, Jakubietz RG (2011) The use of beta-tricalcium phosphate bone graft substitute in dorsally plated, comminuted distal radius fractures. Journal of orthopaedic surgery and research, 6:24 Reference 8: Sripada S, Rowley DI, Saito M, Shimada K, Nakashima T, Wigderowitz CA (2006) Biomechanical testing of the fractured distal radius treated with a new bone cement--is it strong enough? J Hand Surg Br, 31(4):385-389 Reference 9: Kainz H, Dall'ara E, Antoni A, Redl H, Zysset P, Weninger P (2013) Calcium phosphate cement augmentation after volar locking plating of distal radius fracture significantly increases stability. European journal of orthopaedic surgery & traumatology : orthopedie traumatologie

♦ No relevant financial relationships to disclose

E-poster 142: Evaluation of Patients after Secondary Cubital Tunnel Surgery: Psychometric Response Scale versus DASH Score

Category: Surgical Technique, Prognosis/Outcomes Keyword: Elbow and Forearm Level 3 Evidence

♦ Benjamin Z Phillips, MD, MPH ♦ Gregory C Ebersole, MSc ♦ Christine B. Novak, PhD ♦ Susan E. Mackinnon, MD

Hypothesis: The purpose of this study was to evaluate patients after secondary cubital tunnel surgery. We hypothesized that revision transmuscular ulnar nerve transposition (UNT) would significantly decrease pain and improve function.

Methods: Following institutional ethics board approval, we performed a retrospective chart review of consecutive patients receiving a revision transmuscular UNT (from Jan 2008 – Dec 2012) after being referred to the senior surgeon for recurrent cubital tunnel syndrome. Primary outcomes at baseline and final postoperative visit included: the DASH, pain evaluation questionnaire scores and strength (pinch and grip). Statistical analyses were used to assess changes in these outcome measures. Additionally, postoperative changes in primary outcome measures were compared to similar measures in consecutive patients receiving primary UNT for cubital tunnel syndrome (n= 89, mean age 48.4 years).

Results: Revision UNT surgeries were performed in 52 extremities (50 patients: average age 47.4 years; 58% male). Intraoperative findings included distal ulnar nerve kinking (61%), residual medial intermuscular septum (61%), medial antebrachial cutaneous (MABC) neuroma (61%), MABC pseudoneuroma (47%), compression at the medial epicondyle (43%), and severe scarring (71%). Pain intensity and impact of pain on QoL were significantly improved from baseline (p < 0.01). DASH and pinch and grip strength showed trends of improvement, but no significant changes. Using backward elimination regression, the significant predictors of higher pain intensity (dependent variable) following revision UNT were greater number of prior surgical procedures (p = 0.03) and higher preoperative pain intensity (p = 0.05). Average follow-up time of 5.2+3.6 mo and 3.6+3.0 mo for revision and primary UNT, respectively. Compared to primary UNT (previously published data), revision UNT showed a significantly greater increase in grip strength, and significantly less improvement in DASH scores. (Figure 1)

Summary Points: - Most common findings in revision UNT include distal ulnar nerve kinking, residual medial intermuscular septum, and MABC neuroma. - Revision UNT significantly improved the impact of pain on QoL - Compared to primary UNT, revision UNT produces equivalent changes in postoperative pain, but no difference in early reports of disability as defined by the DASH score. - Because pain is usually the chief complaint in this patient population, the VAS scale of pain and QoL may represent a better indicator of postop outcomes in patients undergoing revision UNT

Table 1: Patient Characteristics

No. 52

Age (SD) 47.4 (13)

Female sex 22 (42%)

Surgery on dominant hand 27 (60%)

BMI (SD) 28.6 (6.2)

Co-morbidities

Smoking 26 (50%)

Diabetes 7 (13%)

Hypothyroid 5 (10%)

Arthritis 14 (27%)

Back pain 26 (50%)

Neck pain 19 (37%)

Complex Regional Pain Syndrome 1 (2%)

Use of pain meds 26 (50%)

Worker’s compensation 16 (31%)

Number of previous releases

1 35 (67%)

>1 17 (33%)

Previous surgical procedure

Decompression 19 (39%)

Subcutaneous transposition 31 (63%)

Submuscular transposition 15 (31%)

Neurolysis 4 (8%)

Mean interval since primary (mo) 31 (29)

Mean interval since most recent release (mo) 24 (25)

Mean static 2-PD

Ulnar >6 mm 20 (39%)

Median > 6mm 8 (15%)

Normal EMG 14 (27%)

♦ No relevant financial relationships to disclose