International Guest Hand Society Japanese Society for Surgery of the Hand

Poster Abstract Book

71st Annual Meeting of the American Society For Surgery Of The Hand Guest Society Poster 01: Plasma microRNA-155 is a Potential Biomarker of Acute Rejection after Hind Limb Transplantation in Rats

AUTHORS Hiroki Oda, MD Ryosuke Ikeguchi, MD, PhD Soichi Ohta, MD, PhD Yukitoshi Kaizawa, MD Hirofumi Yurie, MD Shuichi Matsuda, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Reconstruction PURPOSE/CATEGORY - Basic Science LEVEL OF EVIDENCE: N/A

HYPOTHESIS The development of immunosuppressive regimens has resulted in many cases of successful hand transplantations being performed throughout the world. However acute and chronic rejection remains a major problem. Visual skin inspection and histological evaluations are used to assess rejection of hand transplants, however, these methods are largely subjective. Recently, microRNAs (miRNAs) have been recognized as minimally invasive biomarkers of various diseases, including acute rejection after organ transplantation. We hypothesized that some miRNAs are differentially expressed and can be biomarkers in acute rejection of limb transplantations.

METHODS Six male Brown-Norway rats (RT1-n), weighting 210–290 g, were used as donors. Eleven male Lewis rats (RT1-l), weighting 230–330 g, were used as the recipients. The hind limbs of the donor rats were transplanted orthotopically to recipient rats. We administered 1 mg/kg per day FK506 by intramuscular injection for 7 days beginning on the day of transplantation. Skin changes were noted daily. Skin biopsies were obtained from the transplanted hind limb at 7, 10, and 14 days post-transplant. Thin sections of the skin were prepared, stained with Hematoxylin and eosin, and assessed using a grading system for skin rejection, according to Büttemeyer. Plasma samples were obtained before transplantation and at 7, 10, and 14 days post-transplant. miRNAs were isolated from the plasma, reverse transcribed to cDNA and measured using real time polymerase chain reaction. miRNAs were analyzed using the delta-delta Ct method with spike-in of ath-miRNA-159a to normalize miRNA levels. These data were statistically analyzed using student’s t test and the differences were considered significant at P < .05.

RESULTS Skin changes occurred at a mean of 11.1 days post-transplant. Skin biopsies at 7 and 10 days post-transplant showed incomplete histological rejection classified as grade 0-1. Whereas, most skin biopsies at 14 days post-transplant showed histological rejection classified as grade 3. We found that plasma miRNA-155 was significantly up-regulated at 10 and 14 days post-transplant, compared with that at 7 days post-transplant (P = 0.040 and P = 0.026, respectively). No significant changes were found in plasma expression of miRNA-182, and miRNA-451 post- operatively.

SUMMARY POINTS  Expression of miRNA-155 was upregulated at 10 and 14 days post-transplant compared with that at 7 days post-transplant.  The up-regulation of the plasma miRNA-155 was detected before the observation of complete rejection in visual skin inspection or histological assessment.  Plasma miR-155 represents a potential biomarker of acute rejection after vascularized composite tissue allotransplantation.

FIGURES

Guest Society Poster 02: Total Wrist Arthrodesis with the Wrist Fusion Rod for Patients with Rheumatoid Arthritis

AUTHORS Kenji Onuma, MD, PhD Koji Sukegawa, MD, PhD Kentaro Uchida, PhD Naonobu Takahira, MD, PhD Akimasa Kobayashi, MD, PhD Masashi Takaso, MD. PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Reconstruction PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS The Wrist Fusion Rod (WFR) is a relatively new instrument designed by Dr. Ishikawa for total wrist fusion of the rheumatoid wrist(Reference 1). We retrospectively reviewed the short term surgical outcome of wrist fusion using WFR in our hospital.

METHODS Six wrists of four patients with severely distracted rheumatoid wrists categorized as Larsen IV or V underwent total wrist fusion using WFR (Figure 1). Clinical outcome was assessed using a numeric rating scale (NRS) of pain (NRSP) and satisfaction (NFSS) level. We also assessed bony fusion, correction of palmar subluxation and ulnar shift, rod bending angle, wrist fusion angle and complications from radiographs.

RESULTS On NRS assessment, mean NRSP at pre- and post-operation were 8.0 and 1.0, respectively, and mean NRSS was 8.2 (Table 1). These results indicate that wrist fusion by this procedure significantly reduced pain and that the results were satisfactory. All wrists achieved painless wrist stability with bony fusion of the radiocarpal joint. Surgery corrected both the palmar subluxation and ulnar shift in all cases. Two radiographic complications were observed, rod fracture and a radiolucent band in a proximal metacarpal bone in one case each. Both complications might have occurred as a result of instability of the third carpometacarpal joint, but neither influenced clinical outcome. Wrist fusion angle was smaller than rod bending angle at final observation.

SUMMARY POINTS  Wrist fusion using the WFR is one option for treatment of the severely distracted rheumatoid wrist.  Our experience suggests the need to assess the stability of third carpometacarpal joint before surgery, and to fuse this joint if indicated.  Surgeons should note that the bending angle of the intramedullary rod does not directly form the wrist fusion angle, in contrast to the case with a dorsal wrist fusion plate.

REFERENCES 1. Ishikawa H. Total wrist arthrodesis (in Japanese). Arthritis -undoukishikkan to rinsho. 2007; 5: 88-97.

FIGURES

Guest Society Poster 03: Metacarpophalangeal Joint Arthroplasty Using Flexible Hinge Toe Implant for the Deformity of the Rheumatoid Thumb

AUTHORS Tetsuya Nemoto, MD, PhD Hajime Ishikawa, MD, PhD Asami Abe, MD, PhD Katsunori Inagaki, MD, PhD Youichi Toyoshima, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Reconstruction PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS The boutonniere deformity of the thumb is the most common deformity of rheumatoid thumb and it accounts for 50 to 74% of the involved thumbs. Metacarpophalangeal(MP) joint arthroplasty is indicated for the deteriorated MP joint with preserved soft tissue stability. Feldon introduced to use flexible hinge toe implant for the MP joint reconstruction because of its better mechanical strength compared to finger joint implant (Reference 1). We hypothesized rheumatoid thumb reconstruction using flexible hinge toe implant would improve the clinical outcomes and radiological findings.

METHODS Swanson implant arthroplasty for at the thumb MP joint was performed on the 68 cases (male 11, female 57) between November 2006 and December 2014. The average age was 64 yrs. old and the average follow-up period was 3 yrs. The duration of the rheumatoid arthritis at the time of surgery was 22 years. Combined with this MP joint arthroplasty, arthrodesis at the IP joint in 20 thumbs, capsulodesis at the IP joint in 3 thumbs and suspensionplasty at the CM joint (Thompson) in one thumb were performed. Radiological assessments were performed in 56 cases, clinical evaluation was performed in 47 cases. We assessed range of motion, grip power, side pinch power, general health using visual analog scale (VAS) and DAS28-CRP. Wilcoxon rank sum test was used as a statistical analysis.

RESULTS A painless motion and stability was provided to the thumb in most of the patients. In the radiological assessment, the pre- and the postoperative flexion angles at the MP joint were 45 and 17 degrees, and extension angles at the IP joint were 44 and -1 degree(s). In the clinical assessment, the average range of motion was 21 degrees, with 44 degree in flexion and -23 degrees in extension. The average grip strength changed from 117 to 125 mmHg (p=0.775) and the average side pinch power changed 1.5 to 2.1kgw (0.047). The patients were satisfied with their appearance of the thumb. General health using VAS improved from 41 to 29 (0.019) and DAS28-CRP was decreased 3.3 to 2.4(p=0.00). In one case, postoperative infection occurred and implant was removal of required. Joint stability and prehension pattern improved by arthrodesis or capsulodesis.

SUMMARY POINTS  By the rheumatoid thumb surgery, deformity was corrected and hand function improved.  The ratio of implant failure was lower than that in the previous reports (Reference 2).

REFERENCES 1. Feldon P, Millender LH, Nalebuff: Rheumatoid arthritis in the hand and wrist. Operative Hand Surgery, pp 1587-1690, Churchill Livingstone, New York, 1993. 2. Bieber EJ, Weiland AJ, Volnec-Dowling S. Silicone rubber implant arthroplasty of the metacarpal-phalangeal joints for rheumatoid arthritis. J Bone Joint Surg Am 1986;68:206-9

Guest Society Poster 04: Selection of Tendon Transfer or Tendon Graft on Wide-awake Tendon Reconstruction with Evaluation of Muscle Degenerative Disorder Using Active Muscle-tendon Excursion

AUTHORS Mineyuki Zukawa, MD Ryusuke Osada Tomoatsu Kimura

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Reconstruction PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Selection of tendon transfer or tendon graft in the tendon reconstruction depends on potential amplitude of ruptured muscle-tendon. Wide-awake hand surgery is useful for tendon reconstruction because surgeons can observe the active muscle-tendon excursion during the surgery. We hypothesized that active muscle-tendon excursion during the wide-awake surgery is considered as a useful index to evaluate ruptured muscle-tendon degeneration and donor muscle function in the tendon reconstruction.

METHODS We enrolled 36 patients who underwent tendon transfer or tendon graft on wide-awake hand surgery. We measured the passive muscle-tendon excursion and active muscle-tendon excursion of the ruptured tendon during the surgery. Correlation between the passive and active muscle- tendon excursion and correlation between the each excursion and the rupture duration were investigated.

Furthermore, we compared the post-operative results between wide-awake group and non-wide- awake group in 19 flexor tendon reconstruction for flexor tendon ruptures in zone 4 and 5. They included 9 flexor pollicis longus (FPL) and 10 flexor digitorum profundus (FDP). The wide- awake group included local anesthesia and ultrasound-guided selective sensory nerve block was 9 cases 11 tendons. The non-wide-awake group included general anesthesia and total nerve block was 8 cases 8 tendons.

RESULTS Passive muscle-tendon excursion significantly related to active muscle-tendon excursion of ruptured muscle-tendon. (Pearson coefficient of correlation r = 0.60, p < 0.01)(Fig.1) There was no significant correlation between the muscle-tendon excursion and the rupture duration, but only the active muscle-tendon excursion of the FPL tended to related to the rupture duration. (Fig.2) In 19 flexor tendon reconstruction, ROM (%Total active motion) and Disabilities of the Arm, Shoulder and Hand (DASH) score were improved after the operation. There was no significant difference of post-operative ROM and DASH score between two groups.

SUMMARY Passive muscle-tendon excursion significantly related to the active muscle-tendon excursion of ruptured muscle-tendon in vivo on the wide-awake surgery. Therefore there is no significant difference of post-operative results between the wide-awake group that was able to observe the active muscle-tendon excursion and the non-wide-awake group that observed only the passivec muscle-tendon excursion. Active muscle-tendon excursion may be useful index to evaluate ruptured muscle-tendon degeneration and donor muscle function in the standard tendon reconstruction.

REFERENCES 1. Lalonde DH,Wong A. Dosage of local anesthesia in wide awake hand surgery. J Hand Surg Am. 2013; 38:2025-2028 2. Fridén J, Ward SR, Smallwood L, Lieber RL. Passive muscle-tendon amplitude may not reflect skeletal muscle functional excursion. J Hand Surg Am. 2006; 31(7):1105-10. 3. Nakanishi Y, Omokawa S, Kobata Y, Shimizu T, Kira T, Onishi T, Hayami N, Tanaka Y. Ultrasound-guided selective sensory nerve block for wide-awake forearm tendon reconstruction. Plast Reconstr Surg Glob Open. 2015; 3(5):e392

FIGURES

Guest Society Poster 05: Wide Awake Surgery for Rheumatoid Hand

AUTHORS Ryusuke Osada, MD, PhD Mineyuki Zukawa Tomoatsu Kimura

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Reconstruction PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Reconstructive surgery with tourniquet-free pure local anesthesia (wide awake approach) is known to allow for the observation of the total active movement during the surgery. We report our experience of reconstructing extensor tendons and metacarpophalangeal (MCP) joints with wide awake approach in the patients with rheumatoid arthritis (RA).

METHODS Seven participants underwent the reconstructive surgery for rheumatoid hand under local anesthesia using mixture of 1% lidocaine with 1:200,000 epinephrine and a same dose of 0.75% ropivacaine. The reconstruction of finger extensor tendons combined with Sauvé-Kapandji procedure was conducted in 4 participants, and reconstruction methods included tendon graft in 6 fingers, end-to-side adjacent tendon suture in 2, extensor carpi radialis tendon transfer in 1. The realignment of ulnar displaced tendon on MCP joint was carried out in 2 participants. The surface replacement arthroplasty of MCP joint was performed in 1 participant. At final postoperative follow-up ranging from 6 to 15 (mean: 12) months, we measured MCP, PIP joint range of motion (ROM) and extension lag and statistically evaluated the relationship between postoperative extension lag and several clinical factors.

RESULTS We could complete the surgery under local anesthesia in all participants, and could observe total active movement during reconstruction of tendons or joints. According to these findings, we could decide the adequate tension of the reconstructed tendon, and showed the active movement to the patient (Figure 1, 2). Every participant looked the recovered finger motion before wound closure. At final postoperative follow-up, the active ROM was more than 90% of that observed at surgery in each participant . All of the participants satisfied about the results of treatment. Summary Points

SUMMARY Surgery for rheumatoid hand with wide awake approach was useful mean to tendon reconstruction, correction of ulnar deviation, and arthroplasty of finger joint.

REFERENCES 1. Bezuhly M, Sparkes G L, Higgins A, Neumeister MW, Lalonde DH: Immediate thumb extension following extensor indicis proprius-to-extensor pollicis longus tendon transfer using the wide-awake approach.Plastic & Reconstructive Surgery119: 1507-1512, 2007. 2. Mannerfelt LG: Tendon transfers in surgery of the rheumatoid hand. Hand Clin. 4: 309, 1988. 3. Longo U G, Petrillo S, Denaro V:Current Concepts in the Management of Rheumatoid Hand. Int J Rheumatol. 2015

FIGURES

Guest Society Poster 06: Medium Term Post-Operative Outcomes of Reconstruction for Dislocation of the Extensor Tendon inn Elson Technique

AUTHORS Megumi Hanaka, MD Nobuyuki Takahashi, MD Kousuke Iba, MD Kohei Kanaya, MD, PhD Toshihiko Yamashita, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Reconstruction PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Chronic dislocation of the extensor tendon at the metacarpophalangeal joint is a rare condition without rheumatoid arthritis. We haveperformed surgical treatment for the dislocation of extensor tendon using Elson technique, of which procedure was used an extensor tendon half slip anchored aroud the deep transverse metacarpal ligament. The aim of this study is to evaluate the medium term post-operative outcomes.

METHODS Between 2000 and 2013 with minimum follow-up time of 24 months, five patients with eight fingers (male 1, female 4; mean age 42 years) suffering from dislocation extensor tendon of the finger without rheumatoid arthritis were enrolled. The index finger was affected in one finger, the long finger in 5 fingers and ring finger in 2 fingers. The factors predisposing to dislocation were old trauma in one finger, spontaneous in 3 fingers and congenital in 4 fingers. The average post-operative follow-up was 60 months. Surgical procedure was performed by Elson technique which the extensor tendon was stabilized with a distally based tendon half slip passed through around the radial side of the deep transverse metacarpal ligament. The splint was adjusted to stop until 60° flexion at MP joint for 3 weeks, and to permit active extension. After 3 weeks active mobilization excersice was started. We evaluated post-operative outcomes including complications, recurrence, pain, range of motion (ROM) of the finger, Disabilities of the Arm, Shoulder and Hand (DASH) score and patient satisfaction.

RESULTS Post-operative complications occurred in two cases. One was hypertrophic scar, the other was tenosynovitis. There was no recurrence of dislocation of the extensor tendon. All patients were free from pain and the fingers had a full range of motion. Patients demonstrated a high level of satisfaction.

SUMMARY POINTS  Although there are many reports on the good short term outcomes for reconstruction of dislocation extensor tendon, the long term outcomes are rarely reported.  Elson techniquecan reconstruct stabilized extensor tendon, while it's unknown whether the reconstructive tendon function for long term after the surgery. In this study, we showed that Elson technique was effective for the treatment of chronic dislocation of the extensor tendon at the metacarpophalangeal joint at medium-term follow-up.

REFERENCES 1. Elson R.A.,: Dislocation of the extensor tendons of the hand. J Bone Joint Surg.49B: 324- 326, 1967 2. Goro I, Yukihisa T.,: Dislocation of the extensor tendons over the metacarpophalangeal joints. J hand Surg. 21A: 464-469, 1996 3. Hidemi K.,et al: loop operation for dislocation of the extensor tendon. J. Jpn. Soc. Surg. Hand 27: 610-612, 2011

Guest Society Poster 07: Postoperative Result of the Carpal Tunnel Syndrome: A Prospective Multicenter Study

AUTHORS Yukinobu Kamiya, MD Yasuaki Tojo, MD Akio Minami, MD, PhD Yoji Mikami, MD, PhD Norimasa Iwasaki, MD, PhD Akinori Sakai, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Reconstruction;Nerve PURPOSE/CATEGORY - Treatment;Prognosis/Outcomes LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Carpal tunnel syndrome (CTS) is one of the most common disease in the field of hand surgery. There have been many studies regarding postoperative results of open carpal tunnel release for CTS. However, postoperative course of recovery of nerve function and how to evaluate nerve function is still uncertain.

Objectives in this study are (1) how to evaluate relationship between postoperative ADLs and physiological findings, (2) how to evaluate postoperative recovery and (3) how many months (or years) are necessary to determine final results after carpal tunnel release.

METHODS We performed open carpal tunnel release in 102 hands of 86 patients with CTS at five institutions during April, 2014 and December, 2015. There were 16 males and 70 females. The average age was 68.1 years old ranging from 25 to 91. Fifty-nine hands were followed 6 months, and 34 hands were followed 1 year after surgery.

Postoperative results were evaluated by physical findings including Phalen test, Tinel-like sign, and motor deficits (in particular, muscle weakness of abductor pollicis brevis muscle) and sensory deficits (2-PD and Semmes-Weinstein monofilament tests). In addition, we evaluated ADLs by quick DASH questionnaire. Motor nerve distal latencies of the median nerve were also measured.

Physical findings, quick DASH and distal latency were collected in all patients at the time of preoperative, 6 months postoperative and 1 year postoperative.

RESULTS Postoperative quick DASH scores and distal latencies of the median nerve significantly improved six months after surgery compared with preoperative values (p<0.05). On the other hand, there was no significant difference in postoperative improvements between six months and one year after surgery. All hands were divided into two groups by the value of the distal latency. One is hands belonging greater than 8.0 milliseconds or unmeasurable (severe group), and the other is less than 8.0 milliseconds (mild group). Twenty-five hands were classified as severe group and twenty-six hands as mild group.

Quick DASH scores in both groups postoperative results were significantly improved compared with the preoperative (p<0.05). However, there was no tendency suggesting a correlation of preoperative severity and postoperative ADLs.

SUMMARY POINTS  The purpose of this study is to analyze the relationship of postoperative ADLs and physiological findings for CTS.  Quick DASH scores and distal latencies significantly improved six months after surgery compared with the preoperative values(p<0.05).  there was no tendency suggesting a correlation of preoperative severity and postoperative ADLs.

This research was supported by a grant received from The Japan Labour Health and Welfare Organization.

Guest Society Poster 08: Factors Correlating Hand Function in Operative Treated Dupuytren’s Disease: Short-Term Follow-Up

AUTHOR Yasunobu Nakagawa, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPICS Hand and Wrist Reconstruction; Systemic Diseases and Disorders

PURPOSE/CATEGORY Evaluation/Diagnosis; Treatment; Therapy/Rehabilitation

LEVEL OF EVIDENCE: Level 4

HYPOTHESIS The functional impairment of patinets following the surgically treatment of Dupuytren’s disease can be influenced by several factors including age, grip strength, and postoperative pain as well as restriction of finger motion. We hypothesized that finger motion was not the primary factor contributing to post-operative hand impairment and explored parameters related to functional recovery as measured by the HAND20.

METHODS We assessed the outcome of 22 patients (23 hands) treated by fasciectomy from January 2008 to December 2014. HAND20, range of motion of affected joints, grip strength, and pain (numeric rating scale: 0-10) measures were collected preoperatively, 1 month postoperatively, and at a 6 month follow-up. Correlation of HAND20 was analyzed using the Spearman correlation. We set explanatory variables: sum of fixed-flexion contractures (FFC), improvement of contractures (final FFC -preoperative FFC), grip strength, pain, and age. Correlation was categorized as small (r = 0.10–0.29), intermediate (r = 0.30–0.49), or large (r = 0.50–1.00)

RESULTS There were 21 male and 1 female patients. The mean age at surgery was 69 years (57 to 81). The mean FFC improved from 80.8 to 13.6 at 1 month to 11.0 at 6 months. None had recurrence in the follow-up period. Despite the improvement of finger motion HAND20 scores, grip strength, and pain worsened at 1 month after surgery (15.6/30.5/2.0 to 23.4/24.2/2.9 respectively). These scores had improved at final evaluation (8.0/31.0/1.4). Both final FFC and improvement of the contractures had small correlate with final HAND20 scores. Although preoperative pain and HAND20 had an intermediate correlation, pain at final follow-up had a large correlation to final HAND20 score.

SUMMARY We conclude that the amount of contracture or its improvement was not the primary factor in hand function of surgically treated Dupuytren’s disease with short-term follow-up. Decreasing the deformity leads to improvement in hand function. In this study, we evaluated the outcomes based on HAND20, a twenty-item, patient-reported functional measurement regarded as suitable for use with an elderly population. Dupuytren’s disease is benign but progressive and often recurs after surgical treatment or collagenase injection. Longer follow-up may alter the significance of these parameters related to hand function. In the future, reports focusing on patient-rated functional measurements can provide useful information to make treatment decisions.

REFERENCES 1. Suzuki, M., Kurimoto, S., Shinohara, T., Tatebe, M., Imaeda, T., & Hirata, H. (2010). Development and validation of an illustrated questionnaire to evaluate disabilities of the upper limb. J Bone Joint Surg Br, 92(7), 963-969. 2. Draviaraj, K. P., & Chakrabarti, I. (2004). Functional outcome after surgery for Dupuytren's contracture: a prospective study. J Hand Surg Am, 29(5), 804-808. 3. Draviaraj, K. P., & Chakrabarti, I. (2004). Functional outcome after surgery for Dupuytren's contracture: a prospective study. J Hand Surg Am, 29(5), 804-808. 4. Chen, N. C., Srinivasan, R. C., Shauver, M. J., & Chung, K. C. (2011). A systematic review of outcomes of fasciotomy, aponeurotomy, and collagenase treatments for Dupuytren's contracture. Hand (N Y), 6(3), 250-255. 5. Sennwald, G. R. (1990). Fasciectomy for treatment of Dupuytren's disease and early complications. J Hand Surg Am, 15(5), 755-761.

Guest Society Poster 09: Smith’s Fracture Generally Occurs as a Consequence of a Fall on the Palm of the Hand

AUTHORS Yusuke Matsuura, MD, PhD Tomoyuki Rokkaku, MD, PhD Takane Suzuki, MD Kazuki Kuniyoshi, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Basic Science; International LEVEL OF EVIDENCE: N/A

HYPOTHESIS Orthopedic trauma surgeons often encounter volar displacement of distal radius fracture (Smith’s fracture) in patients who claimed to have fallen on the palms of their hands. The aim of this study was to reveal the pathogenesis of Smith’s fracture in terms of its clinical and basic aspects.

METHODS We investigated the pathogenesis of Smith’s fracture using a step-by-step approach. First, in our out-patient clinic, we performed a survey investigating the mechanism of injury and the arm position at the time of injury in patients with Smith’s fractures. Second, we created a three- dimensional finite element model and predicted the arm position at the time of injury. Finally, we provided experimental proof of Smith’s fractures resulting from an impact on the palmar side using ten fresh frozen cadavers with the arm position predicted by finite element analysis.

RESULTS Seventeen patients with Smith’s fractures were enrolled, including three males and 14 females (mean age, 67 years). Injury resulting from a fall on the palm and the dorsal of the hand were observed in 12 cases (71%) and in one case (6%), respectively. Four patients were uncertain about their arm position at injury. In the prediction analysis using the finite element model, Smith’s fracture occurred when the angles formed by the meeting of the long axis of the forearm with ground were between 30° and 45° in the sagittal plane and between 75° and 90° in the coronal plane. In the experimental study using fresh frozen cadavers, Smith’s fractures occurred in 7/10 wrists, whereas Colles’ fractures were not observed.

SUMMARY This study demonstrated that a Smith’s fracture results from falling on the palm of the hand.

FIGURES

Guest Society Poster 10: Evaluation of Flexor Pollicis Longus Tendon Irritation with Color Doppler Imaging after Volar Plate Fixation for Distal Radius Fracture

AUTHOR Yoshitaka Tanaka, MD, PhD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Previous methods in evaluation of flexor pollicis longus (FPL) tendon irritation to prevent tendon rupture after volar plate fixation for distal radius fracture seem not to be sensitive and objective. We hypothesized that color Doppler imaging allows better visibility and objectively detects FPL tendon irritation.

METHODS We used a sonographic device to evaluate the condition of the FPL tendon in 40 patients who underwent fixation using a distal volar locking plate for a distal radius fracture. Doppler waveforms of the FPL tendon were evaluated under continuous doppler wave mode dividing the waveforms into three groups; type 1: spindle wave, type 2: spindle wave with spike, and type 3: spike wave. We also assessed the FPL tendon injury at plate removal operation in 20 patients.

RESULTS Contact between the FPL tendon and edge of the plate was positive in 16 of 40 patients. Waveforms were type 1, type 2, and type 3 in 23, 11, and 6 patients, respectively, in the affected hand; and type 1 and type 2 in 37 and 3 patients, respectively, in the contralateral hand. Five patients with type 3 waveform and 15 with type 1 or 2 waveform underwent surgery for plate removal. We found positive tendon injuries in three of the five patients with type 3, and none with type 1 or 2 waveform. Waveforms changed to type 1 or 2 after plate removal in all five patients with type 3.

SUMMARY Type 3 Doppler waveform can be an abnormal finding, and it may be appropriate to recommend plate removal surgery for patients with type 3 Doppler waveform to prevent FPL tendon rupture. Evaluation of doppler waveform of the FPL tendon can be a useful method to predict the existence of the tendon irritation, because of improved visibility and objectivity.

Guest Society Poster 11: The Utility of Computed Tomography for Risk Evaluation of Flexor Tendon Injury Following Distal Radius Fracture Fixation - Case Control Study

AUTHORS Katsuhiro Tokutake, MD Nobuyuki Okui, MD, PhD Hitoshi Hirata, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Our hypothesis is that only radiography is insufficient for risk evaluation of flexor tendon injuries following distal radius fracture fixation and so additional information with Computed tomography is necessary. To verify our hypothesis, we investigated the relationship between volar locking plate placement and flexor tendon injury with radiography and CT-scan.

METHODS We retrospectively assessed the relationship between volar locking plate placement and flexor tendon injury in 99 hands of 94 patients who had radiography and CT-scan after plate fixation for distal radius fracture between October 2005 and August 2015. Flexor tendon injury was classified into "tendon irritation" and "tendon rupture". The presence of pain or uncomfortable feeling or subdermal crepitus around the wrist with a finger motion were defined as symptoms of flexor tendon irritation. We graded plate prominence using the Soong grading system, and we measured the plate-to-critical line distance (PCL) and the plate-to-volar rim distance (PVR), volar tilt and ulnar variance of final follow-up radiographs. Furthermore, we assessed these parameters with CT and designated them respectively as CT- Soong grade, CT-PCL, CT-PVR (where flexor pollicis longus (FPL) was located).We also surveyed the contact between plate and volar cortical bone with radiographs and CT. Statistical significance between groups was analyzed with the Mann-Whitney U test and Pearson's chi-square test. The McNemar Test was used to compare radiographs with CT.

RESULTS We found 17 flexor tendon injuries (17.2%) including 5 (5.1%) FPL tendon rupture (Group A). The rest of the patients (82.8%) were assigned to Group B. Median age was 61.4 (IQR:57-72) years-old in Group A and 59.1 (IQR:50-72) years-old in Group B (P=0.79). Volar tilt of final follow-up (P=0.008) and PCL, CT-PCL (P<0.001) showed significant difference between groups. But, ulnar variance of final follow-up (P=0.26), PVR (P=0.62) and CT-PVR (P=0.76) were not significantly different between groups. 35 cases (35.4%) were classified as grade 0 by X-ray, however only 7 of them remained in the same category on CT. Moreover, We judged that 41 cases (41.4%) had a gap between plate and volar cortical bone on CT in contrast with 15 Cases (15.4%) by X-ray.

SUMMARY POINTS  X-ray tends to underestimate the plate mal-positioning compared to CT.  Volar tilt and PCL, but not PVR, were useful predictors of delayed tendon injury after volar locking plate fixation.  To decrease tendon injury, we need to contact between plate and volar cortical bone.

REFERENCES 1. Soong M, Earp BE, Bishop G, Leung A, Blazar P. Volar locking plate implant prominence and flexor tendon rupture. J Bone Joint Surg Am. 2011;93(4):328-335. 2. Kitay A, Swanstrom M, Schreiber JJ, et al. Volar plate position and flexor tendon rupture following distal radius fracture fixation. J Hand Surg Am. 2013;38(6):1091-1096. 3. Tada K, Ikeda K, Shigemoto K, Suganuma S, Tsuchiya H. Prevention of flexor pollicis longus tendon rupture after volar plate fixation of distal radius fractures. Hand Surg. 2011;16(3):271-275. 4. Imatani J, Akita K, Yamaguchi K, Shimizu H, Kondou H, Ozaki T. An anatomical study of the watershed line on the volar, distal aspect of the radius: implications for plate placement and avoidance of tendon ruptures. J Hand Surg Am. 2012;37(8):1550-1554. 5. White BD, Nydick JA, Karsky D, Williams BD, Hess AV, Stone JD. Incidence and clinical outcomes of tendon rupture following distal radius fracture. J Hand Surg Am. 2012;37(10):2035-2040. 6. Limthongthang R, Bachoura A, Jacoby SM, Osterman AL. Distal radius volar locking plate design and associated vulnerability of the flexor pollicis longus. J Hand Surg Am. 2014;39(5):852-860. 7. Sonya P. Agnew, Karin L. Ljungquist, Jerry I. Huang. Danger zones for flexor tendons in volar plating of distal radius fractures. J Hand Surg Am. 2015;40(6):1102-1105. 8. Tanaka Y, Aoki M, Izumi T, Fujimiya M, Yamashita T, Imai T. Effect of distal radius volar plate position on contact pressure between the flexor pollicis longus tendon and the distal plate edge. J Hand Surg Am. 2011;36(11):1790-1797. 9. Saeed Asadollahi, Prue P. A. Keith. Flexor tendon injuries following plate fixation of distal radius fractures: a systematic review of the literature. J Orthopaed Traumatol (2013) 14:227–234. 10. Orbay JL, Touhami A. Current concepts in volar fixed-angle fixation of unstable distal radius fractures. Clin Orthop Relat Res. 2006;445:58-67.

FIGURES

Guest Society Poster 12: Intraarticular Step-Offs of Distal Radius Fractures Evaluated with Computed Tomography

AUTHOR Katsuhisa Tanabe, MD, PhD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Evaluation/Diagnosis;Anatomy;Basic Science LEVEL OF EVIDENCE: N/A

HYPOTHESIS Because residual intraarticular step-off is strongly associated with subsequent osteoarthritis in the radiocarpal joint, the assessment of step-off is critical for the treatment of distal radius fractures. We hypothesized that intraarticular step-offs of dorsiflexed fractures had different properties from those of volar shearing fractures. We tried to document precise locations of intra- articular step-offs by CT scans and classify step-offs for each of dorsiflexed fractures and volar shearing fractures.

METHODS With computed tomography, 116 intraarticular fractures of the distal radius from 112 patients were examined. Multiplanar CT images and/or 3D images were assessed. Among them, we extracted 30 fractures with intraarticular step-offs more than 1mm in the radiocarpal joint in at least one image of either sagittal or coronal planes. Then, we categorized the fractures into two fracture groups (dorsiflexed fractures and volar shearing fractures).

RESULTS In 18 fractures in dorsiflexed fractures, we found 3 characteristic types of step-offs. Three fractures had step-offs in the periphery of the central depressed fragments. Seven fractures had step-offs in the sagittal plane in the middle of the articular surface and the volar steps were lower. Eight fractures had step-offs in the coronal plane at the ulnar side of the articular surface and the ulnar steps were lower. In contrast, 12 volar shearing fractures had one major type of step-off. Eleven fractures had step-offs in the sagittal plane extending to the periphery of the articular surface and the volar steps were lower.

SUMMARY We documented the step-offs of intraarticular fractures lines of the distal radius. We found that each of dorsiflexed fractures and volar shearing fractures had specific types of intraarticular step- offs. The findings might help in the evaluation and treatment of intraarticular step-offs of distal radius fractures.

REFERENCES 1. Giannoudis PV, Tzioupis C, Papathanassopoulos A, Obakponovwe O, Roberts C. Articular step-off and risk of post-traumatic osteoarthritis. Evidence today. Injury. 2010;41:986-995. 2. Rozental TD, Bozentka DJ, Katz MA, Steinberg DR, Beredjiklian PK. Evaluation of the sigmoid notch with computed tomography following intra-articular distal radius fracture. J Hand Surg. 2001;26A:244-251. 3. Harness NG, Ring D, Zurakowski D, Harris GJ, Jupiter JB. The influence of three- dimensional computed tomography reconstructions on the characterization and treatment of distal radial fractures. J Bone Joint Surg. 2006;88A:1315-1323. 4. Katz MA, Beredjiklian PK, Bozentka DJ, Steinberg DR. Computed tomography scanning of intra-articular distal radius fractures: does it influence treatment? J Hand Surg. 2001;26A:415-421. 5. Pruitt DL, Gilula LA, Manske PR, Vannier MW. Computed tomography scanning with image reconstruction in evaluation of distal radius fractures. J Hand Surg. 1994;19A:720- 727. 6. Johnston GH, Friedman L, Kriegler JC. Computerized tomographic evaluation of acute distal radial fractures. J Hand Surg. 1992;17A:738-744. 7. Tanabe K, Nakajima T, Sogo E, Denno K, Horiki M, Nakagawa R. Intra-articular fractures of the distal radius evaluated by computed tomography. J Hand Surg 2011;36A:1798-1803.

Guest Society Poster 13: Normal Range of Motion of Thumb Metacarpophalangeal Joint

AUTHORS Tatsuki Ebata, MD, MD,PhD Ikuo Nakai, MD, MD Akira Kogura, MD, MD Kenichiro Goto, MD, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Evaluation/Diagnosis;Therapy/Rehabilitation LEVEL OF EVIDENCE: Level 1

HYPOTHESIS It is known that range of motion (ROM) of thumb MP joint differs widely among individuals. Due to these variations, it is impossible to determine some degrees as normal ROM. For this reason, comparison with normal side is essential in ROM exercises for thumb MP joint contracture. The purpose of this study was to define difference between right and left ROM of the thumb MP joint in normal population and assess the utility value of normal side normal as indicator.

METHODS Three hundred hands of 150 subjects without history of injuries or diseases of the thumb were included in this study. Seventy-five were men and 75 were women. The average age was 36.1 years of age. To exclude degenerative joint disease, subjects were 20 or more and less than 50 years of age. Flexion angle and extension angle of the MP joints were measured with goniometer at one-degree intervals. Statistical analysis of flexion angle, extension angle, difference between men and woman, and difference between right and left were carried out.

RESULTS The average flexion angle was 59.5 degrees (from 16 to 90). The average extension angle was 7.9 degrees (from -32 to 58). Both flexion and extension angle were greater in women than in men. The average difference of flexion angle between right and left was 4.8 degrees (from 0 to 28). The average difference of extension angle between right and left was 6.4 degrees (from 0 to 38). When p value was 0.05, the one-sided 100p percentile of flexion angle was determined as 10.6 degrees and extension angle was determined as 14.3 degree. When p value was 0.01, the one-sided 100p percentile of extension angle was determined as 15.1 and extension angle was determined as 20.1 degree.

SUMMARY POINTS  Due to large differences in flexion and extension angles, it appeared that some angles could not be determined as normal.  The difference between right and left in flexion angle was 4.8 degrees and that in extension was 6.4 degrees. They were small enough to consider as normal indicators.  The results of one-sided 100p percentile illustrated that flexion loss of more than 11 degrees and extension loss of more than 15 degrees were suspicious of contracture of the MP joint, flexion loss of more than 16 degrees and extension loss of more than 21 degrees strongly suggested contracture of the MP joint.

REFERENCES 1. Yoshida R1, House HO, Patterson RM, Shah MA, Viegas SF. Motion and morphology of the thumb metacarpophalangeal joint. J Hand Surg Am. 2003 Sep;28(5):753-7. 2. Hume MC1, Gellman H, McKellop H, Brumfield RH Jr. Functional range of motion of the joints of the hand. J Hand Surg Am. 1990 Mar;15(2):240-3.

FIGURES

Guest Society Poster 14: The Range of Dart-Throwing Motion: Reliability of a Measuring Method by Use of Tablet Device

AUTHORS Yoshihiro Dohi, PhD Aya Suhara, OT Kenji Kasubuchi, PT Ryotaro Fujitani, MD Shohei Omokawa, MD,PhD Yasuhito Tanaka, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Evaluation/Diagnosis;Therapy/Rehabilitation LEVEL OF EVIDENCE: N/A

HYPOTHESIS The dart-throwing motion (DTM) is a functionally very important movement from radial extension to ulnar flection of the wrist and the anatomical and biomechanical futures have been demonstrated experimentally.1, 2 Clinically, there is the only report to be published to describe the method of goniometric measurement for DTM but the reliability of measurement has not been evaluated.3 We hypothesized that our DTM measurement method using a tablet device and a simple jig can be a more reliable method.

METHODS Subjects were 10 healthy volunteers for assessing intra-rater reliability and 3 examiners for inter- rater reliability. Range of extension-flexion and DTM were evaluated. Subjects moved their wrist in each motion plane on a flat table. While the DTM measurements, their hand was fixed to an isosceles right triangle jig and kept their wrist rotation 45 degrees obliquely on the table, so they moved their wrist freely in a DTM plane on the table (Fig. 1). Photo images at each maximum wrist position from right overhead were recorded using a tablet device and the angle was measured by goniometric software lunched on the device (Fig. 2). Reference points were marked on subject’s skin before recording images according to our protocol (Fig. 3). Intra-class correlation coefficients were compered to determine intra and inter-rater reliability, using the SPSS soft wear package (p<0.05).

RESULTS All results are shown in Table 1. According to the guideline provided by Landis and Koch,4 there was substantial intra-observer (ICC=0.67, 0.71) and inter-observer (ICC=0.77, 0.72) in flexion and extension, respectively. We observed almost perfect intra-observer (ICC=0.92) and substantial inter-observer (ICC=0.79) in ulnar flexion and substantial intra-observer (ICC=0.62) in radial extension in a DTM plane. There was moderate inter-observer (ICC=0.59) in radial extension in a DTM plane.

SUMMARY POINTS  The results of the study indicate that the measuring method of the range of motion by use of tablet device can maintain fixed reliability or more.  Intra and inter-rater reliability of our method of measurement for dart-throwing motion compares favorably with conventional flexion-extension motion.  The recording of photo image can transform a three-dimensional object to the plane figure and make the measurement easy.

REFERENCES 1. 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(12):2729- 40. 2. 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(3):611-21. 3. Bugden B. A proposed method of goniometric measurement of the dart-throwers motion. J Hand Ther. 2013 Jan-Mar;26(1):77-9. 4. Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics.1977;33(1):159–174.

FIGURES

Guest Society Poster 15: Incidence of Tendon Rupture after Volar Locking Plate Fixation of Radius Distal Fractures

AUTHORS Kotaro Sato, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Prognosis/Outcomes LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Tendon ruptures are a well-known postoperative complication of using the volar locking plate (VLP) system. The purpose of the present study was to assess the frequency of tendon rupture on a large scale in patients with distal radius fracture (DRF)s who were treated with the VLP system.

METHODS A questionnaire was administered by an orthopedic surgeon who performed the surgeries in patients with DRFs in our prefecture. Thirty institutions were enrolled in this study. The questionnaire consisted of two parts. The first part comprised the number of patients who underwent surgery using the VLP and the number of patients who suffered a tendon rupture between January 2011 and December 2014. The second part comprised the surgeon’s policy for removing the implant after bone union was achieved.

RESULTS All 30 institutions responded to the first part of the questionnaire, and 50 orthopedic surgeons who were working at the institutions answered the second part of the questionnaire. During the 4-year period, 2,787 patients with DRFs underwent fixation using a VLP. The overall incidence of flexor pollicis longus(FPL) rupture, extensor pollicis longus rupture, flexor digitorum profundus (index finger) rupture, and extensor digitorum communis rupture were 0.35% (10/2,787), 0.29% (8/2,787), 0.04% (1/2,787), and 0.04% (1/2,787), respectively. Regarding the question about implant removal, 18 surgeons responded that they removed the implant in almost all cases, 25 answered that they removed the implant depending on the case, and 7 responded that they usually do not remove the implant.

SUMMARY This study evaluated 2,787 patients with DRFs who underwent fixation using a VLP. FPL rupture occurred in 10 patients (0.35%), whereas other tendon ruptures occurred less often. Implant removal was performed by more surgeons in our prefecture.

REFERENCES 1. Volar plate fixation for the treatment of distal radius fractures: analysis of adverse events. 2. Risk Assessment of Tendon Attrition Following Treatment of Distal Radius Fractures With Volar Locking Plates Using Audible Crepitus and Placement of the Plate: A Prospective Clinical Cohort Study

Guest Society Poster 16: Wide-Awake Surgery for the Metacarpal Fracture

AUTHORS Takashi Kashiwa, MD Takuro Wada, MD Osamu Sato, MD Kohei Kanaya, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Wide-awake surgery with tumescent technique, the subcutaneous infiltration of a large dose of dilute anesthetic solution mixed with adrenaline, creates a painless and bloodless operative field and eliminates the risks associated with the use of a tourniquet, general anesthesia, and sedation. This technique is suitable for many hand surgery cases. However, metacarpal fractures are difficult to completely anesthetize with this technique. We had some cases who had intraoperative pain and were treated with additional selective nerve blocks at the wrist. The purpose of this study is to evaluate our anesthetic technique for metacarpal fractures.

METHODS The authors conducted a retrospective review of 18 cases who were diagnosed with a metacarpal fracture and had wide-awake surgery between December 2010 and December 2015. Observations were made concerning sex, age, location of metacarpal fracture, type of procedures performed, duration of procedures, and complications.

RESULTS A total of 18 cases were reviewed, distributed among 16 males and 2 female. Average age was 38 years (range, 11-86 y). The most common locations of metacarpal fracture were fifth (8 cases), followed by first (4 cases), fourth (3 cases), second (2 cases), unknown (1 case). The types of procedures performed were open reduction and internal fixation (9 cases), closed reduction and internal fixation (9 cases). All 18 patients received injections of 1% lidocaine with epinephrine (1:100,000) in the hand in a dose range of 10 to 30cc and an average dose of 20cc. Average duration of procedures was 25 minutes (range, 1-80min). Two cases had persistent pain when the reduction maneuver was performed or when a Kirschner wire was inserted into the bone. Additional selective nerve blocks at the wrist were performed and complete pain relief was achieved among both of them.

SUMMARY Metacarpal fractures are difficult to completely anesthetize with the tumescent technique only. The residual pain probably emerges from the bone. The authors recommend injecting a dose of dilute anesthetic solution not only in the subcutaneous tissue but also around the periosteum and fracture site. If an enough pain relief is not achieved intraoperatively, additional selective nerve blocks at the wrist can be useful for complete pain relief.

REFERENCES 1. Lalonde DH. Wide-awake flexor tendon repair. Plast Reconstr Surg. 2009;123(2):623- 625. 2. Ceran C et al. Selective Nerve Block Combined With Tumescent Anesthesia. J Hand Surg Am. 2015;40(12):2339-2344. 3. Lalonde DH. Wide Awake HAND SURGERY. New York: CRC Press. 2016

Guest Society Poster 17: Reconstruction of Fingertip Amputations with a Flap and Composite Graft Technique

AUTHOR Hikaru Ogawa, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS The aim of this study is reviewed the results of a flap and composite graft technique for the fingertip amputation.

METHODS This technique is used to the cases amputated at subzone 2 or 3 (Ishikawa et al., 2001) when microsurgical anastomosis is hard to be performed. The soft tissue of palmer side is resected, then the nail and nail bed with distal phalangeal bone are reattached to the proximal amputated the proximal stump of distal phalangeal bone by the Kirschner wire fixation. The palmer side of fingertip is made by finger island flap; the volar advancement V-Y for indicated to the thumb and the oblique triangular flap for other fingers (Hirase et al., 2003). From January 2011 to October 2013, the flap and composite graft technique was used in 10 patients with 11 injured fingers. The mean patient age was 34.2years (range, 21 to 58years); nine were men and one were women. Nine cases were amputated in subzone 2 and two cases were amputated in subzone 3. The injuries were distributed over the digits as 1 thumb, 1 index, 3 middles, 5 rings and 1 small.

RESULTS At a mean follow-up was 9.7 months (range, 5 to 18months). Consequently ten fingers survived in 11 cases. One failure case was amputated at subzone 3. Survival rate of this study for the amputated at subzone 2 or 3 was 90.9%. Sensation was normal within a few weeks time. In two patients, a slight contracture in the distal interphalangeal joint was noted.

SUMMARY POINTS  We reviewed our results of the flap and composite graft technique for the fingertip amputation.  Survival rate of this study for the amputated at subzone 2 or 3 was 90.9%.  One failure case was amputated at subzone 3.  This technique is useful in the treatment of fingertip amputation at subzone 2.

Guest Society Poster 18: Abdominal Pocket Method as a Salvage Procedure for Vascular Insufficiency after Distal Digital Replantation, and One Case Report by Palmar Pocket Method

AUTHORS Seiji Sawai, MD Toshihiro Kitayama, MD Haruo Soeda, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS The purpose of this study is to assess the utility of pocketing of a de-epithelialized reattached digit to allow for neovascularization as a salvage procedure for circulatory insufficiency after digital replantation. We performed the abdominal pocket method in Tamai Zone II cases where microsurgical vascular anastomosis was expected to be difficult based on the findings at the initial operation. Furthermore, we performed the palmar pocket method in one case. We hypothesized that the pocketing method was useful as a salvage procedure after digital replantation.

METHODS From 2008 to 2014, 5 injured digits from 5 patients (mean age: 34 years, range: from 25 to 54 years) underwent the abdominal pocket method as a salvage procedure for postoperative circulatory insufficiency. We evaluated the survival incidence, the timing between operations, and the duration of the second operation. During this study period, 7 amputated digits from 7 patients underwent vascular re-anastomosis. We also evaluated the survival incidence for these cases. In addition, we evaluated 1 injured digit salvaged by the palmar pocket method.

RESULTS Four out of 5 replanted digital tips survived. The mean time between the initial operation and the onset of vascular problems was 82 hours, and the mean duration of the second operation was 48 minutes. The survival incidence for re-anastomosed cases was 6 out of 7. For the case salvaged by the palmar pocket method, the digital tip completely survived.

SUMMARY POINTS  The abdominal pocket method is useful for treating circulatory insufficiency after digital replantation in Tamai zone II cases where microsurgical vascular re-anastomosis was expected to be difficult based on the findings at the initial operation.  The palmar pocket method could be the alternative to the abdominal pocket method in the same condition.

REFERENCES 1. Tamai S. Twenty years' experience of limb replantation: review of 293 upper extremity replants. J Hand Surg. 1982;7(6):549-556. 2. Brent B. Replantation of amputated distal phalangeal parts of fingers without vascular anastomoses, using subcutaneous pockets. Plast Reconstr Surg. 1979;63(1):1-8. 3. Arata J, Ishikawa K, Soeda H, et al. The palmar pocket method: an adjunct to the management of zone I and II fingertip amputations. J Hand Surg Am. 2001;26(5):945- 950. 4. Nakajima T. How soon do venous drainage channels develop at the periphery of the flap? A study in rats. Br J Plast Surg. 1978;31:301-308.

FIGURES

Guest Society Poster 19: Outcomes of Complete A2 Pulley Release After Flexor Tendon Repairs in Zone II Followed by Early Active Mobilization

AUTHORS Koji Moriya, MD, PhD Takae Yoshizu, MD Naoto Tsubokawa, MD Hiroko Narisawa, MD Kei Hara, MD Yutaka Maki, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Pulley release occasionally needs to be extended to a large portion of the A2 pulley to improve digital function after primary flexor tendon repair. The purpose of this study was to review the outcomes relating to the release of the entire A2 pulley to facilitate zone II flexor tendon repairs using a six-strand suture followed by early postoperative active mobilization.

METHODS Between 1993 and 2015, a total of 102 fingers in 88 consecutive patients with complete zone II flexor digitorum profundus (FDP) lacerations were treated using the Yoshizu #1 technique followed by early active mobilization. According to Tang’s subdivisions of zone II, seven patients (seven digits) with zone 2c (the area covered by the A2 pulley) tendon injuries required the complete release of the A2 pulley. Our indications for the surgical release of the A2 pulley were: (1) the ends of the lacerated FDP tendon were difficult to pass under the A2 pulley; (2) the A2 pulley had to be opened to achieve surgical tendon repair; or (3) the repaired site could not be passed easily through the residual part of the pulley. The A2 pulley was completely released when the A1 and distal to A3 pulleys were preserved. The flexor digitorum superficialis tendon was repaired in six fingers and excised locally in one. Mobilization of the digits began with a combination of active extension and passive and active flexion in a protective splint on the first postoperative day. The follow-up period averaged 9 months (range, 6–12 months). Clinical results were evaluated using the total active motion (TAM), Strickland’s criteria, and Tang’s criteria.

RESULTS At the final follow-up, the mean TAM was 231° (range, 190–262°). According to Strickland’s criteria, four digits were ranked excellent, two good, and one fair. Using Tang’s criteria, two digits were ranked excellent, four good, and one fair. No tendon ruptures or subjective bowstringing occurred in any of the patients.

SUMMARY The A2 pulley was traditionally deemed the most important in terms of digital fuction. However, Savage stated that the maximal changes associated with incisions into even the A2 and C1 pulleys were experimentally small in terms of FDP tendon excursion and bowstringing. In addition, our data may clinically support the view that release of the entire A2 pulley does not influence tendon function when the remainder pulleys are left intact.

REFERENCES 1. Strickland JW, Glogovac SV. Digital function following flexor tendon repair in Zone II: A comparison of immobilization and controlled passive motion techniques. J Hand Surg Am, 5:537-543,1980. 2. Tang JB. Outcomes and evaluation of flexor tendon repair. Hand Clin, 29:251-259,2013. 3. Savage R. The mechanical effect of partial resection of the digital fibrous flexor sheath. J Hand Surg Br, 15:435-442,1990. 4. Tang JB. The double sheath system and tendon gliding in zone 2c. J Hand Surg Br, 20:281-285,1995. 5. Moriya K, Yoshizu T, Maki Y, Tsubokawa N, Narisawa H, Endo N. Clinical outcomes of early active mobilization following flexor tendon repair using the six-strand technique: short- and long-term evaluations. J Hand Surg Eur, 40:250-258,2015.

Guest Society Poster 20: Serious Complication of Operation for Distal Radius Fractures - The 20 Cases of Palmar Subluxation after the Fixation of Volar Locking Plate

AUTHORS Keikichi Kawasaki, MD, PhD Katsunori Inagaki, MD, PhD Hermann Krimmer Joerg Gruenert Martin Leixnering Christoph Pezzei, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS In the treatment of distal radius fractures, palmar subluxation of radio-lunate or radio-carpal after volar locking plate fixation is one of the most severe complication. Harness reported 7 failure cases of AO type B3-3 without support of volar lunate facet fragment, and it was referred to as volar shearing fracture1). The ulno-volar corner of distal radius is important for stability because it is not only the maximum loading point of the wrist but also the attachment point of the ligament and the joint capsule. We investigated the treatment methods and their results of our 20 cases of subluxation after volar locking plating, and hypothesized that the size of fragment and the rate of coverage of fragment by volar plate is small.

METHODS The 20 cases of subluxation after volar locking plate fixation due to insufficiency of supporting volar lunate facet fragment were subjected to this study. The mean age was 57.7years old. Two cases was both side. The fracture type at the time of injury was 3 cases of dorsal displacement (Colles) type and 17 cases of volar displacement (Smith) type, and 8 cases of B3 and 12 cases of C3 by AO classification

RESULTS The all initial surgeries were performed by volar locking plate fixation (monoaxial locking plate: 7 cases, polyaxial locking plate: 13 cases). Re-fixation with volar plating after palmar subluxiation was performed in 4 cases. For one case, although the operation of re-fixation was repeated three times in total, subluxation occurred. As the cause of palmar subluxation is insufficiency of buttress support of volar lunate facet fragment, improper screw insertion to fix the fragment, and insufficiency of preventing subluxation should be considered. 4 cases were operated arthrodesis because of severe arthrosis. The average size of volar lunate facet fragment in longitudinal diameter at the point from ulnar, 0, 5, and 10mm was measured. VLF fragment was small, less than 10mm from the joint surface. When we look at the plate coverage on the fragment, one half of the fragment was covered by the plate transversely and one-third was covered longitudinally. More than these coverage might be important for the radio-lunate stability.

SUMMARY The risk of subluxation was under 10mm of the size of fragment and one-third coverage of fragment by volar plate, longitudinally. It is important support the volar lunate facet fragment perfectly, to prevent subluxation.

REFERENCES 1. Harness NG, et al. Loss of fixation of the volar lunate facet fragment in fractures of the distal part of the radius. J Bone Joint Surg 86-A: 1900-1908, 2004.

Guest Society Poster 21: Clinical Outcome of Internal Fixation Using the HERATY Plate for Unstable Distal Radius Fractures

AUTHORS Tomonori Nakanishi, MD, PhD Yoshifumi Ueshin, MD Tetsuo Kojima, MD, PhD Tomoyuki MIzoguchi, MD Hikaru Ogawa, MD Dai Murata, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS We investigated the clinical outcome of internal fixation using the fixed-angle locking plate (HEARTY plate, Mizuho) for unstable distal radius fractures. Our hypothesis was that surgical outcome had been constant in all AO classification of distal radius fractures.

METHODS We examined the 91 cases (92 wrists) that had been operated for internal fixation with the HEARTY plate between 2011-2013 in our hospital, and were followed appropriate postoperative period. There were 23 male and 68 female patients, and one case underwent surgery for bilateral wrist injuries. Mean age was 60.0 years, and mean follow-up period was 5.4 months. According to the AO-classification, 26 wrists were included in type A, 5 wrists in type B, 61 wrists in type C. We examined the operation time, radiographic parameters (Radial inclination; RI, Volar tilt; VT, and Ulnar variance; UV) at the preoperative period, immediate postoperative period, and final follow-up period. Cooney's wrist score determined in all cases. The score was compared statistically among the AO groups.

RESULTS Mean operation time was 58.6 minutes including wrist arthroscopic surgery, and simultaneous operations were done for distal ulna fracture, 4th and 5th metacarpal fracture and scaphoid fracture. During the immediate postoperative period, radiographic parameters were significantly corrected within the appropriate values in all groups. However, correction loss of UV occurred in AO-C1 and C3 groups at the final follow-up period. ROM arc was improved more than 120° in all groups. Cooney's score was also improved in all groups, especially mean Cooney's score in the C3 group (score 86.5). There were five fair results due to forearm compartment syndrome and the effect of the UV correction loss.

SUMMARY Volar locking plate technique using the HEARTY plate allows for short operation time and good clinical result even for unstable fractures of the distal radius such as type C2 and C3. Further studies to help predict which patients are at risk for postoperative UV correction loss would be required to improving the long-term outcome.

Guest Society Poster 22: Clinical Results for Distal Radius Fracture in the Elderly Women, Operated with Polyaxial Locking Plate (VA-TCP)

AUTHORS Nobuaki Okamatsu, MD Keikichi Kawasaki Jun Ikeda, MD, PhD Wakako Sakamoto, MD Shotaro Hashimoto, MD Katsunori Inagaki, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Polyaxial locking plates (PLP) are useful for operation especially in intra-articular fracture cases, because of their multi-directional, angular stabilized locking system.But it is said that PLPs sometimes lack in angular stability of the screws, which result in reduction loss after operation. We reviewed distal radius fracture cases of elderly women, which were operated with PLP (VA- TCP, Synthes Inc.). We evaluated outcome of the treatment and discussed the cases which had postoperative dislocation.

METHODS Records from 33 patients with distal radius fracture, aged 65 years or older, were analyzed. Patients were treated with VA-TCP. Mean age was 71.6 years old, all the patients were female, 16 patients injured in right hand, 17 in left. Average follow-up duration were 9.2 months. Fracture type (AO classification) and number of cases was: A2;2 cases, A3;4 cases, C1;9 cases, C3;18 cases. The fractures were classified as followed: extra-articular/intra-articular (6 cases/27 cases), simple-metaphysis/comminuted-metaphysis (11 cases/22 cases), simple-intra- articular/comminuted-intra-articular (9 cases/ 18cases). They were compared together and evaluated. Clinical results were measured with Cooney score. X-ray results were measured by (i)ulnar variance, (ii)volar tilt, (iii)radial inclination. Reduction loss was determined by difference of X-ray findings between after-operation and last-visit. T-test was applied for statistic procedure, and significant difference was defined when P<0.05.

RESULTS The average result for all 33 cases were as followed: Cooney score was 86.3 point, reduction loss was 0.76mm/0.68deg/0.29deg (ulnar variance/volar tilt/radial inclination).In general, fractures were reduced well and maintained throughout the follow-up period.In each comparison of fracture classifications, no significant difference was found. Post operative displacement was found in 3 cases (9.1%). Details of postoperative displacement was as followed: transposition of distal fragment over the plate(1 case). Screw rupture into joint because of dislocation (1 case), Back-out of proximal screws(1 case).

SUMMARY Regardless of types of fracture, reduction positions were statistically well maintained in X-ray examination. Strength of VA-TCP was considered to be reliable in this study. However some case reports of implant trouble in VA-TCP were done. We need to have further research.

Guest Society Poster 23: A Biomechanical Comparison of Volar Locking Plating for Distal Radius Fractures with Die-punch Fragment

AUTHORS Takaaki Kanazawa, MD Kazunari Tomita, MD, PhD Keikichi Kawasaki Katsunori Inagaki, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Basic Science;International LEVEL OF EVIDENCE: Level 3

HYPOTHESIS The Frag-loc(®) screw system for distal radius fracture was designated with the aim of fix the displaced dorsoulnar (die-punch) fragment of the distal radius fracture. Theoretically, use of the Frag-loc(®) screw system is predictably effective for the fracture which has dorsally displaced intra-articular dorsal fragment(1). The purpose of this study was to determine whether the Frag- loc(®) screws significantly affects the stability of simulated distal radius fracture with die-punch fragment fixed with volar locking plate.

METHODS Eight matched pairs of cadaveric radiuses were prepared to simulate distal radius fracture with die-punch fragment. Specimens were fixed using the volar plating system with Frag-loc(®) screws (F) or Locking screws (L). These screws were used to fix the die-punch fragment. Each specimen was loaded at a constant rate of 0.5mm/min to failure. Load data was recorded and, ultimate strength and change in the gap between die-punch fragments and proximal fragments were measured, and the change rate was calculated by dividing the gap before and after loading. Data for ultimate strength and change of the gap were compared between specimens with F group and L group. Failure was defined as 10mm or more of displacement of the fragment, or screw failure. Bone Mass Density of these specimens was measured by Archimedes’ principle.

RESULTS The ultimate strength is correlate with bone mineral density (BMD) (R=0.56). Between specimens with F and L, there is no significant difference in the ultimate strength. After loading, there is no significant difference in the change of the gap between the distal and proximal fragment (p=0.054).

However, there was a trend toward increased stiffness in fractures fixed with Fragloc(®) screws.

SUMMARY POINTS  Ultimate strength in case with higher BMD was higher than that with lower BMD.  Ultimate strength is not significantly different between Frag-loc(®) screw group and Locking screw group.  Although there was a trend toward increased stiffness in fractures fixed with Frag-loc(®) screws, the results were not statistically significant compared with fractures fixed with Locking screws.

REFERENCES 1. Lee JI, Cho JH, Lee SJ. The effects of the Frag-Loc(®) compression screw on distal radius fracture with a displaced dorsoulnar fragment. Arch Orthop Trauma Surg. 2015 Sep;135(9):1315-21.

Guest Society Poster 24: Surgical Fixation Using Artificial Bone Block For Comminuted Distal Radial Fractures Suppresses Reduction Loss After The Surgery

AUTHORS Ryosuke Sato, MD Naohito Hibino, MD, PhD Kazuma Wada Kenji Kondo Tomoya Terai Yoshitaka Hamada, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 3

HYPOTHESIS On the past decade, volar locking plate has become the most popular technique in the treatment of distal radial fractures(DRFs). Rigid fixation using these plates allowed for early mobilization, restoring the wrist function. However, for comminuted DRFs, it is difficult to stabilize to anatomical alignment only using volar locking plate and that treatment often require additional methods.

We hypothesized surgical fixation using artificial bone block suppressed reduction loss after the surgery and investigated the change of postoperative anatomical alignment of the distal radius.

METHODS This single-center prospective (retrospective) cohort trial enrolled adult patients undergoing the surgery for the fractures of the distal radius. A total of 86 patients with the open reduction and internal fixation were seen in this series between March 2013 and September 2015. All patients underwent volar locking plate. Patients were excluded if they underwent additional fixation using external fixator. Of these, 18 patients were added to artificial bone blocks.

15 patients, who belong to the same AO/ASIF classification as artificial bone block used group, were treated without bone block and compared as control group.

Imaging data using preoperative and postoperative radiographs were examined for radial alignment including radial tilt(RT), volar tilt(VT) and ulnar variance(UV).

Statistical analysis was done using a Mann-Whitney U test.

RESULTS At the population of patients by AO/ASIF classification, B3.3 was three, C2.1 was three C2.2 was one, C2.3 was one, C3.1 was three and C3.2 was seven. In Postoperative alignment of the cases using artificial bone block, the mean of RT was 22.3°(22.3°), VT was 11.3°(9.9°) and UV was -0.5mm(0.4mm). In Postoperative reduction loss, the group with artificial bone block, RT was 1.1°(1.4°), VT was 1.2°(3.6°) and UV was 0.7mm(1.3mm). () showed control group.

SUMMARY Volar locking plate is a good implant of the fixation for the distal radial fractures(DRFs), but in comminuted DRFs, those treatment still be challenging. This analysis indicates surgical fixation using artificial bone block is effective for preventing reduction loss after the surgery.

FIGURES

Guest Society Poster 25: Long-Term Results of Pedicled Adipose Tissue for Treatment of Chronic Digital Osteomyelitis

AUTHORS Mitsuhiro Okada, MD, PhD Takuya Uemura, MD Takuya Yokoi, MD Kosuke Shintani, MD Hiroaki Nakamura, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS We have reported a novel surgical technique of pedicled vascularized tissue transfer for treating chronic digital osteomyelitis together with mid-term results. In this report, we demonstrate mid- term results of this technique to evaluate the efficacy for the treatment of chronic osteomyelitis of digits.

METHODS Adipose tissue nourished by the digital artery was obtained at the level of the proximal phalanx based on anterograde or retrograde flow. The vascularized adipose tissue was inserted into the dead space after bone debridement. Eight patients were treated with this procedure from 2009 to 2012. One patient was lost during the follow-up. One patient had chronic osteomyelitis in the thumb, 4 in the index finger, 1 in the middle finger, and 1 in the ring finger. Foci of chronic osteomyelitis were located at the distal phalanx in 2 patients, at the distal phalanx to the middle phalanx via the distal interphalangeal joint in 4, and at the proximal phalanx in 1. Mean duration of follow-up was 60 months. We assessed the efficacy of the technique by clinical symptoms and imaging.

RESULTS We used retrograde pedicled adipose tissue transfer in 6 patients and anterograde pedicled adipose tissue transfer in 1. The pedicled adipose tissue was successfully transferred from the digital tip to its base. The postoperative courses were uneventful; no additional treatments were required. Postoperative physical data and follow-up images showed no evidence of chronic osteomyelitis. No functional loss was caused by procuring vascularized adipose tissue from the digits.

SUMMARY Pedicled vascularized adipose tissue transfer based on the digital artery is reliable and reproducible with evidence of the long-term results. This technique is utilized for chronic osteomyelitis from the tip to the base of digits without microsurgical anastomoses. In addition, function of affected digits is not disturbed. We recommend it as a treatment option for chronic digital osteomyelitis.

REFERENCES 1 Okadam, Kamano M, Uemura T, Ikeda M, Nakamura H. Pedicled adipose tissue for treatment of chronic digital osteomyelitis. J Hand Surg Am. 2015;40(4):677-684. 1. Cirrincione C, Stern PJ. The abductor digiti minimi muscle flap: an adjunct in the treatment of metacarpal osteomyelitis. J Hand Surg Am. 1991;16(5):824-827. 2. Isenberg JS. Additional experience with hemi-metatarsal vascularized bone transfer for treatment of phalangeal osteomyelitis. J Reconstr Microsurg. 2000;16(7):547-551. 3. Kakinoki R, Ikeguchi R, Nakamura T. Second dorsal metacarpal artery muscle flap: an adjunct in the treatment of chronic phalangeal osteomyelitis. J Hand Surg Am. 2004;29(1):49-53. 4. McFadden JA. Vascularized partial first metatarsal transfer for the treatment of phalangeal osteomyelitis. J Reconstr Microsurg. 1998;14(5):309-312. 5. Giuffre JL, Jacobson NA, Rizzo M, Shin AY. Pyarthrosis of the small joints of the hand resulting in arthrodesis or amputation. J Hand Surg Am. 2011;36(8):1273-1281. 6. Anthony JP, Mathes SJ, Alpert BS. The muscle flap in the treatment of chronic lower extremity osteomyelitis: results in patients over 5 years after treatment. Plast Reconstr Surg. 1991;88(2):311-318.

FIGURES

Guest Society Poster 26: Mechanical Properties and Clinical Results of Novel Bioabsorbable Plates for the Treatment of Fractures of the Upper Extremity

AUTHORS Akinori Sakai, MD, PhD Yukichi Zenke Kunitaka Menuki Hideyuki Hirasawa Yoshiaki Yamanaka, MD Takafumi Tajima

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Previous bioabsorbable plates have had several issues with regard to clinical usage. We hypothesized that the mechanical properties of novel bioabsorbable plates are comparable with those of titanium plates in a fracture model and that the clinical results of these new plates are satisfactory for fractures at the upper extremity.

METHODS The first set of experiments compared the mechanical properties of bioabsorbable and titanium plates. Two types of bioabsorbable plates made of hydroxyapatite/poly-L-lactide (1/3- and 1/2- circle in cross-section) and two types of titanium plates (for 1.5- and 2.0-mm screws) were tested. Each plate was fixed on a polyether ether ketone rod, which was transversely cut at its midsection. The second part of the study demonstrated the clinical results of bioabsorbable plates used in 62 cases of 70 hand fractures including 39 metacarpal, 20 distal ulna, 5 distal radius, and 6 radial head fractures since July 2008. The mean age of the patients was 48.4 years. The follow- up period ranged from 3 month to 4 years and 9 months.

RESULTS The bending strength and stiffness of 1/3-circle bioabsorbable plate constructs were comparable with those of titanium plates for 1.5-mm screws, and those of 1/2-circle bioabsorbable plates were comparable with those of titanium plates for 2.0-mm screws. The non-union rate was 2.9% (2/70 cases). 4.3% (3/70 cases) was necessary for implant removal because of loose screws in 2 cases of metacarpal fractures and limited range of motion in one case of radial head fracture. For the consecutive cases with metacarpal fractures, there were no significant differences in 6-month postoperative clinical results between patients receiving bioabsorbable plates after July in 2008 and titanium plates before July in 2008 (267.0 ± 6.0 vs. 250.0 ± 28.3 degrees of total range of active motion, and 92.7 ± 19.7 vs. 86.4 ± 28.6% of contralateral grip strength). SUMMARY The bending strength and stiffness of novel 1/3- or 1/2-circle bioabsorbable plates were comparable with those for titanium plates with 1.5- or 2.0-mm screws. The clinical study of bioabsorbable plates used in fractures at the upper extremity revealed satisfactory results for union rate, range of motion, and grip strength. For metacarpal fractures, there were no significant differences in clinical results between bioabsorbable and titanium plates.

REFERENCES 1. Sakai A, et al. J Bone Joint Surg Am 94:1597-1604, 2012 2. Furukawa K, et al. Tech Hand Up Extrem Surg 18:15-19, 2014 3. Shikinami Y, et al. Biomaterials 20:859-877, 1999 4. Shikinami Y, et al. Biomaterials 22:3197-3211, 2001 5. Hughes TB. Clin Orthop Relat Res 445:169-174, 2006 6. Böstman O, et al. J Bone Joint Surg Am 74:1021-1031, 1992 7. Lionelli GT, et al. Ann Plast Surg 49:202-206, 2002 8. Waris E, et al. J Hand Surg Am 29:452-457, 2004 9. Dumont C, et al. J Hand Surg Am 32:491-496, 2007 10. Yasunaga T, et al. J Biomed Mater Res 47:412-419, 1999

Guest Society Poster 27: Arthroscopically Assisted Transulna Repair for Fovea Dissociation of TFCC with Instability

AUTHORS Kazunari Tomita, MD, PhD Jun Ikeda, MD, PhD Keikichi Kawasaki Katsunori Inagaki, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Recently TFCC injury has become widely known. However, it is still challenging to relieve pain and disability due to TFCC injury. We have performed arthroscopic assisted transulna repair of TFCC injuries with instability to restore native anatomy. We hypothesize that this method can effectively treat fovea dissociation of TFCC injuries with instability.

METHODS Fifty-four patients with arthroscopic assisted transulna repair for fovea dissociation of TFCC with instability were evaluated. The mean age of patients was 36 years(14-64 years). Thirty-one cases were male, 23 cases were female. The mean follow up period was 18.5 month(6-66 month). We investigated the arthroscopic findings and clincal outcomes for each case, with Visual analog scale (VAS), and final clinical evaluation using Japan Society for Surgery of the Hand (JSSH) wrist performance score, complication and non-healing rate.

Surgical technique: All cases had diagnostic radiocarpal joint (RCJ) and distal radioulnar joint (DRUJ) arthroscopy using a 1.9mm and 30°scope. A small longitudinal ulnar sided skin incision was made to protect the dorsal ulnar sensory nerve. Repair of the TFCC was performed with use of bone tunnels placed the about 3cm proximal to the ulna styloid through ulnar shaft distally and exiting in the fovea region. This was arthroscopically aided. An outside-in repair was completed using mainly 2-0 PDS sutures. After repair, the wrist and forearm were immobilized during 6 weeks.

RESULTS See Figure 1 for findings and treatment. The mean of pre-operation VAS was 71.9 (40-90). Finally, the mean VAS statistically improved to 11.4(0-60). The patients of 24 cases (44.4%) declared VAS 0. The final clinical evaluation using JSSH wrist performance score was 92.5 (65- 100); excellent in 50 cases, and good in 4 cases. ECU tenosynovitis was observed in 6 cases, ulna nerve numbness was observed in 2 cases, and loss of supination was 1 case. 31 cases (57.4%) some residual pain at the surgical site.

SUMMARY Meredith L et al described that there was no statistical difference in clinical outcomes after open versus arthroscopic TFCC repair. Our technique which was adopted those both advantages attempts anatomical reconstruction of the TFCC and prevents some complications with a minimally invasive approach. Our technique can provide satisfactory results. All our patients achieved good to excellent results and had significant pain relief.

REFERENCES 1. Meredith L. Anderson, MD, et al. Clinical Comparison of Arthroscopic Versus Open. J Hand Surg. 2008:33A: 675-682.

FIGURES

Guest Society Poster 28: Critical Factors in the Ishiguro Method for Treatment of Mallet Fracture

AUTHORS Kimitoshi Noto, MD, MD Hitoshi Hirata, MD Masahiro Tatebe, MD Michiro Yamamoto, MD Katsuyuki Iwatsuki, MD, PhD Shigeru Kurimoto, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment; Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS The Ishiguro method of percutaneous extension block pinning for mallet fractures is the leading technique, providing good bone union with low invasion. Its use is widespread. However, consensus about optimal fixation angle is lacking and additional factors associated with the surgical results are inadequately understood. The purpose of our study was to investigate outcomes in a series of patients treated using the Ishiguro method, focusing especially on the correlation between fixation angle and extension lag.

METHODS We reviewed 220 consecutive patients who had surgery for mallet fracture between August 2003 and July 2013 in this prospective study. Ultimately, 163 fingers were selected from 160 patients who were treated with the Ishiguro method and had a follow up at more than 2 months. The indication for surgery was a mallet fracture with a displaced dorsal fragment able to be fixed by extension block pin. Mean averages of study participants were: 31.8 years, -8.9 degree fixation angle, 10.7 day preoperative period, 33.9 day fixation period, and 3.1 month observation period. A primary analysis was performed of treatment results such as range of motion (ROM), extension lag, and complications. Then factors including age, size of bone fragment, temporary fixation angle, fixation period, postoperative extension lag, and ROM of the DIP joint were examined using the Spearman correlation function. Additionally, results for each finger were compared.

RESULTS Bone union was attained in 160 of 163 fingers (98%). The mean extension angle was -7.5±9.6 degrees and the mean ROM was 54±15.6 degrees. Age and size of bone fragment were significant factors associated with both extension lag and ROM. Additionally, DIP fixation angle was associated with extension lag while fixation period was associated with ROM. There was no correlation between temporary fixation angle and ROM. Radial fingers tended to have better results than ulnar fingers in a direct comparison.

SUMMARY Postoperative ROM decreases in cases with small bone fragments, a long fixation period and advanced age. Extension lag increases with temporary DIP joint fixation in a flexed position. Radial digits exhibit better results than the little and ring fingers do with the Ishiguro method.

REFERENCES 1. Alla, SR. et al. Current concepts: mallet finger. Hand (NY). 9 (2), 2014, 138-44. 2. Ishiguro, T. et al. Extension block Kirschner wire for fracture dislocation of the distal interphalangeal joint. Tech Hand Up Extrem Surg. 1 (2), 1997, 95-102. 3. Chung, DW. et al. Anatomic reduction of mallet fractures using extension block and additional intrafocal pinning techniques. Clin Orthop Surg. 4 (1), 2012, 72-6. 4. Napier, JR. The prehensile movements of human hand. J Bone Joint Surg Br. 38 (4), 1956, 902-13. 5. Abouna, JM. et al. The treatment of mallet finger. The results in a series of 148 consecutive cases and a review of literature. Br J Surg. 55 (9), 1968, 653-67.

FIGURES

Guest Society Poster 29: Small Syringe Needle Technique: A Modification to Extension Block Pinning for Surgical Treatment of Mallet Fractures

AUTHORS Yusuke Hagiwara, MD, PhD Mitsuhiko Nanno, MD, PhD Ryu Yoshida, MD Yoshihiko Satake, MD Shinro Takai, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Extension block pinning (EBP) is an effective surgical treatment for mallet fractures. Various modifications have been described, including use of an additional K-wire placed through the fragment. We developed a modification in the technique where a small syringe needle is used to fix the fragment prior to EBP placement.

We hypothesized that the small syringe needle technique could be safely used for mallet fractures to obtain good reduction and stability.

METHODS Either a 23G or 27G needle was inserted dorsally into the fragment perpendicular to the fracture line. By gently rotating the syringe back and forth, the needle was advanced into the fragment in a controlled fashion. The fracture was then reduced by finger compression or joysticking. Then, the needle was further advanced for provisional fixation. Placement of EBP further reduced the fracture. At 4–6 weeks when the finger became non-tender, K-wires were removed. The needle was left in place for up to 2 more weeks, depending on the amount of callus formation.

RESULTS 14 consecutive patients (10 males, 4 females; average age 28.3 years, range, 13–57 years) with mallet fracture were treated with this technique. Average fracture size was 50.1% (range, 40.0%– 74.5%) of articular surface. 10 (71.4%) patients had joint subluxation. Average preoperative displacement was 37.6% (range, 16.7%–62.5%). Postoperatively, the average articular gap was 0.6mm, and step off was 0.3mm. These values remained unchanged throughout follow up except in the 2 patients with complications. One patient had a significant injury 2 weeks after hardware removal and re-fractured. Another patient had a superficial infection that resolved with a short course of oral antibiotics; he was a smoker and heavy laborer who had returned to work shortly after surgery. Average time to union was 5.6 weeks. At an average follow up of 4.5 months, ROM of the joint was 54.3° (range, 30°-80°) with an extension lag of 9.2° (range, 0°-30°). The average extension lag excluding the 2 complications was 5.7° (range, 0°-15°). By Crawford classification, 6 patients had excellent, 3 had good, 3 had fair, and the 2 patients with complications had poor results. Mean q-DASH score was 1.3.

SUMMARY POINTS  Small syringe needles can be manually inserted into mallet fragments safely and easily to help reduction and provide additional stability  Compared to K-wires, the needles are sharper and less likely to slip when advancing. They are also smaller and less likely to comminute the fragment.  This inexpensive technique yielded good patient outcomes.

REFERENCES 1. Ishiguro T, Inoue K, Matsubayashi N, Ito Y, Hashizume N. A new method of closed reduction for mallet fractures. Cent Jpn J Orthop Trauma Surg 1988;31:2049–2051. 2. Ishiguro T, Itoh Y, Yabe Y, Hashizume N. Extension block with Kirschner wire for fracture dislocation of the distal interphalangeal joint. Tech Hand Up Extrem Surg. 1997 1(2):95-102. 3. Hofmeister EP, Mazurek MT, Shin AY, Bishop AT. Extension Block Pinning for Large Mallet Fractures. J Hand Surg. 2003;28(3):453-459. 4. Tsubokawa N, Yoshizu T, Maki Y, Yamamoto Y, Yamashita H. Modified Ishiguro's Method for Large Mallet Fractures. J Jpn Soc Surg Hand. 2005:22-2:58-61.

FIGURES

Guest Society Poster 30: Pronator Sparing Volar Approach to Distal Radius Fractures Results in Superior Patient Satisfaction: A Prospective Randomized Controlled Trial

AUTHOR Hiromichi Yasuoka, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique;Prognosis/Outcomes LEVEL OF EVIDENCE: Level 1

HYPOTHESIS Surgical procedures “without pronator quadratus (PQ) releasing” are superior to those “with releasing,” when comparing post-operative clinical outcomes in open reduction and internal plate fixation for distal radius fractures.

METHODS Outcome measures were compared in patients with and without pronator release during open reduction and internal fixation in 30 patients with dorsally angulated fractures of the distal radius. Intra-articular fractures having displacement of joint surface and fractures having comminution of volar cortex were excluded from the study.

The case studies were randomly separated into two groups. One group received surgery ‘without PQ releasing’ (16 patients). The second group received surgery ‘with PQ releasing’ (14 patients). Post operation outcomes were assessed at approximately 6 months after operation using The DASH Outcome Measure and Hand 20, modified Mayo wrist score, range of motion of the wrist and grip strength. Radiographic assessments were performed immediately after each operation and the last follow up appointment.

RESULTS The DASH and Hand 20 score were significantly better in the ‘without releasing’ group than the ‘with releasing’ group. DASH: ‘without releasing’ group average 3.03, range 0~15.91 vs ‘with releasing’ group average 9.31, range 2.5~32.5 (P=0.01). Hand 20: ‘without releasing’ group average 3.9, range 0~19 vs ‘with releasing’ group average 11.1, range 2.5~18.42 (P=0.003). There were no significant differences between the two groups in the other assessed parameters.

SUMMARY POINTS  No statistical difference was observed in the modified Mayo wrist score, range of motion of the wrist, grip strength, operation time and radiographic assessments between the two groups of patients.  In the demonstrated cases of dorsally angulated fractures of the distal radius, the procedures ‘without PQ releasing’ resulted in significantly better subjective recovery than the procedures ‘with PQ releasing’, when considering patient-rated evaluations.

FIGURES

Guest Society Poster 31: Factors Affecting the Clinical Outcomes of Multistrand Repair and Early Active Mobilization Therapy for Acute Zone II Flexor Digitorum Tendon Rupture

AUTHORS Yasunori Kaneshiro, MD, PhD Noriaki Hidaka, MD Hirohisa Yagi, MD Koichi Yano, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique;Therapy/Rehabilitation LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Factors affecting the clinical outcomes of multistrand repair and early active mobilization (EAM) therapy for acute Zone II flexor digitorum tendon rupture were investigated.

METHODS The subjects were 30 fingers of 28 consecutive patients treated with 6-strand flexor tendon repair and EAM therapy for zone II flexor tendon injury. 22 were men and 8 were women with the mean follow-up period was 7 months. Clinical outcomes at the final follow-up period were evaluated according to Strickland’s criteria, and correlations with aging, waiting period for operation from injury, presence of nerve injury, concomitant flexor digitorum superficialis (FDS) injury, and postoperative range of motion (ROM) of the interphalangeal (IP) joints at 4 weeks were investigated.

RESULTS The final outcomes were excellent for 22 fingers, good for 7, and fair for 1. No tendon rupture was observed. The severity of postoperative flexion contracture of the IP joints at 4 weeks was correlated with the final outcome (r=0.41, p=0.02) , and it was also weakly correlated with the severity of flexion contracture of the IP joints at the final follow-up (r=0.31, p= 0.09). The other factors were not correlated with final outcomes.

The current study indicated that, if flexion contracture of the IP joint developed during EAM therapy for Zone II flexor tendon rupture, it tended to persist until final follow-up, and its severity had an effect on the final outcome. Preventing flexion contracture of the proximal IP joint is thus important to improve therapeutic outcomes.

SUMMARY POINTS  Therapeutic outcomes for EAM therapy for Zone II flexor tendon injury were excellent according to Strickland’s assessment criteria in around 90% of cases.  The severity of flexion contracture of the IP joint at 4 weeks postoperatively had an effect on the final outcome.  The prevention of flexion contracture of the PIP joint is particularly important when carrying out EAM therapy.

Guest Society Poster 32: The Examination of Recipient Vessels in Acute-Phase Free Flap Surgery for Severe Upper Extremity Trauma

AUTHORS Hideki Tsuji, MD Natsumi Saka, MD Hirotada Matsui

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Elbow and Forearm Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Post-traumatic vessel disease (PTVD; Khouri1992) is known as a vascular disease associated with severe extremity trauma complicated with soft tissue damage. Blood vessels reached by edema and scar around "zone of injury" readily develop drug-refractory spasm, which generally occurs in patients with lower extremity trauma, and are not suitable for use as recipient vessels in free flap surgery. We assume that PTVD onset in acute-phase free flap surgery for severe upper extremity trauma is rare.

METHODS 35 patients (27 men and 8 women; mean age, 45.0 years (18 -73)) were underwent acute-phase free flap surgery (+ composite tissue graft) for severe upper extremity trauma in our department between 2007.4 and 2014.8. The site of vascular anastomosis was in upper arm-elbow in two cases, forearm-wrist in 24 cases, in a hand in nine cases. Free flap surgery was performed 7.4 days (2 to 18 days) after injury on average. We investigated: 1.The state (disrupted/continuous) of the recipient vessel selected on the findings at the time of injury and CT angiography; 2. Relationship between PTVD onset and the number of days from injury to the operation; 3. Flap survival rate.

RESULTS 1. Disrupted, 17 cases; continuous, 18 cases. 2. PTVD occurred in 4/35 cases (11%), including 3/17 cases in the disrupted group (thumb reconstruction in all cases) and 1/18 cases in the continuous group. The mean number of days from injury to the operation was 11.0 days in the onset group, while it was 6.9 days in the non-onset group. 3. The survival rate was 34/35 = 97%.

SUMMARY PTVD usually occurs in patients with lower extremity trauma, and has been considered a cause for a relatively high failure rate of flap surgery in free flap surgery. However, it was found in this study to occur in the upper extremity in thumb reconstruction cases. The PTVD onset seemed to be related to the number of days from injury to free flap surgery in addition to the location and extent of injury.

REFERENCES 1. Khouri RK: Avoiding free flap failure. Clin Plast Surg 19: 773-781, 1992 2. Godina M: Early microsurgical reconstruction of complex trauma of the extremities. Plast Reconst Surg 78: 285-291, 1986.

Guest Society Poster 33: Ultrasonographic Evaluation of Thenar Atrophy in Carpal Tunnel Syndrome

AUTHORS Issei Nagura, MD, PhD Takako Kanatani, MD, PhD Masatoshi Sumi, MD, PhD Atsuyuki Inui, MD, PhD Yutaka Mifune, MD, PhD Takeshi Kokubu, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Elbow and Forearm Trauma;Shoulder PURPOSE/CATEGORY - Treatment;Surgical Technique;Basic Science LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Quantitative analysis of thenar musculature by ultrasonography is possible and this was applied in evaluating thenar atrophy in patients with carpal tunnel syndrome (CTS).

METHODS Forty two patients with thenar atrophy due to CTS (12 males and 30 females) with a mean age of 69.6 years (range, 35-92 years) were included in this study. Thenar atrophy was classified by visual grading scale: (+) or (++). Ultrasonographic examination was performed to evaluate abductor pollicis brevis (APB) and opponens pollicis (OPP) muscles. The transducer was applied onto the palmer surface of the hand perpendicularly to the longitudinal axis of the first metacarpal bone. Both muscles were analyzed by measuring their thickness; the “APB depth” (from the inserted prominence of the OPP muscle above the first metacarpal bone to the palmar surface) and the “OPP depth” (from the ulnar prominence of the first metacarpal bone to the palmar surface of the OPP) (Figure 1). A control group was comprised of twenty healthy volunteers with a mean age of 34.5 years (range, 30-39 years). The “APB depth” and“OPP depth” were analyzed by Mann –Whitney U test (P<0.05).

RESULTS The averages of the “APB depth” and “OPP depth” in the control group were: male; 9.3±1.3mm and 4.7±0.9mm, female; 7.9±1.3mm and 3.9±0.8mm. The averages of the “APB depth” and“OPP depth” in the patients graded (+) were: male; 9.0±2.0mm and 4.9±1.0mm, female; 6.8±2.1mm and 3.9±0.8mm and in the patients graded (++) were: male; 3.5±1.4mm and 2.9±0.4mm, female; 4.4±1.2mm and 3.1±0.4mm (Table1). Both the “APB depth” and“OPP depth” were decreased significantly parallel with the progression of muscle atrophy.

SUMMARY In this study, the quantification of thenar atrophy in CTS by ultrasonography was demonstrated and could be useful to evaluate not only thenar atrophy level but also postoperative recovery objectively.

FIGURES

Guest Society Poster 34: Scaphoid Non-union Salvaged with Vascularised Second Metacarpal-base Bone Graft

AUTHOR Masaharu Makino, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Hand and Wrist Reconstruction PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Scaphoid non-union, especially status after failed free bone graft, is recalcitrant disease, having poor healing potential by scar tissue and circulatory diaturbance. Proximal fragment sclerosis on plane X-rays and low intensity signals on MRI indicate possible aseptic necrosis. To treat such non-union, vascularized bone graft could be the one of rescue procedures. The author's choice of donor is the base of the second metacarpal base which has rich cancellous bone with a reliable vascular pedicle of the second dorsal metacarpal artery, and all reconstruction procedures can be carried-out in the same hand.

METHODS Surgical procedures: To harvest a graft, a dorsal curved skin incision is made over the second metacarpal base. The second dorsal metacarpal artery is usually visible at the ulnar side of the second metacarpal through the overlaid fascia. A periosteal vascular branch is presented in some cases. An adequate sized vascularised bone for scaphoid can be harvested, and grafted into the non-union. When a previous surgery with hardware was done through volar approach, after removal of it and scar tissue, volary transposed graft underneath the thumb extensor tendons is to be placed into the non-union.

From 1997 to 2014, 13 non-unions in 13 cases were operated. There were 12 male and one female. Seven non-unions, including of three proximal one third non-unions, were previously operated with free iliac bone graft. Six had no previous surgery. Thumb spica cast was applied after surgery untill union on X-rays.

RESULTS All non-unions united in four months after surgery. Pain was complained in one case after strenuous activities. Motion arc was 57 to 100 % of non-operated wrist. Grip strength was 77 to 95 % of the opposite hand.

SUMMARY POINTS  Vascularized bone graft is one of the great choice to treat such recalcitrant scaphoid non- union as failed free iliac bone graft.  Harvesting the graft from the second metacarpal, having the largest base of the matacarpi,  is easy with reliable vascular pedicle of the second dorsal metacarpal artery.  The surgical procedures are carried-out in the injured hand, avoiding to make injury on the other healthy body parts.

REFERENCES 1. Makino M.: Vascularized metacarpal bone graft for scaphoid non-union and Kienboeck's disease. J Reconstr Microsurg.2000; 16: 261-266. 2. Sawaizumi T, Nannno M, Nanbu A, and Ito H: Vascularized bone graft from the base of the second metacarpal for refractory nonunion of the scaphoid. JBJS Br 2004; 86(7): 1007-12.

Guest Society Poster 35: Dorsal Intercarpal Ligament Capsulodesis for Scapholunate Instability

AUTHORS Daisuke Suzuki, MD, MD Shohei Omokawa, MD, PhD Hiroshi Ono, MD, PhD Ryotaro Fujitani, MD Takeshi Katayama, MD Yasuhito Tanaka, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Hand and Wrist Reconstruction PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS We retrospectively evaluated clinical results of novel dorsal intercarpal ligament (DICL) capsulodesis in an attempt to reinforce the scapholunate interosseous ligament (SLIL) in patients with scapholunate instability.

METHODS Eighteen consecutive patients (mean age, 36 years) were diagnosed as SL instability by arthroscopic findings of Geissler grade 4 SLIL tears. Eleven static instabilities with SL intervals were larger than 4mm and 7 dynamic instabilities were included. After arthroscopic evaluation, the dorsal capsuloligament structures were exposed, V-shaped capsulotomy was performed which located just distally along the dorsal radiocarpal ligament and proximally along the DICL. Then, the DICL was elevated in a bipedicled flap fasion. Mini suture anchors attached to 2-0 braided sutures were drilled into the dorsal cortex of the scaphoid and lunate to act as the attachment site for the dorsal SLIL. The ends of the sutures were passed through the DICL to secure it to the scaphoid and lunate. (Figure 1)

We used DASH as subjective outcome and range of motion, grip strength as functional outcomes to evaluate the results. Postoperative radiographs were reviewed to evaluate changes in carpal alignment at final follow-up. Postoperative assessment of DASH scores was compared with preoperative values using Mann-Whitney U test. Objective assessments of the range of wrist motion and grip strength were compared using paired t-tests. The threshold for statistical significance was set at p <.05.

RESULTS The mean follow-up period was 17 months (range, 5-36 months). The postoperative DASH score was 11, which was significantly improved compared with their preoperative values. Postoperative objective assessments indicated that the mean range of wrist flexion was reduced by 4 degrees and the average grip strength was increased by 12 kgf. With regard to radiographic appearance at final follow-up, the mean postoperative SL joint interval was 3.0 mm, which was significantly reduced by 1.3 mm from preoperative measurement values. (Figure 2)

SUMMARY POINTS  We treated 18 patients with Geissler grade 4 SLIL tear by novel dorsal capsulodesis using a bipedicled DICL.  The current procedure achieved improvement of DASH score and prevented re-widening of SL joint interval.

REFERENCES 1. Geissler WB, Freeland AE, Savoie FH, et al. Intercarpal soft-tissue lesion associated with an intra-articular fracture of the distal end of the radius. J Bone Joint Surg. 1996; 78A: 357-365. 2. Berger RA, Bishop AT, Bettinger PC. New dorsal capsulotomy for the surgical exposure of the wrist. Ann Plast Surg. 1995 Jul;35(1):54-9.

FIGURES

Guest Society Poster 36: A Vascularized Bone Graft Based on the 2nd Dorsal Metacarpal Artery for Reconstructing Bone, Cartilage, and Ligaments in the Hand

AUTHORS Hironori Matsuzaki, MD Keiichi Maniwa, MD Masato Ueki

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Hand and Wrist Reconstruction PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Carpal-bone nonunion or necrosis can be treated with several vascularized bone grafts. Among these, a graft based on the 2nd dorsal metacarpal artery (DMA) is the most reliable because of its anatomical consistency and the large diameter of the 2nd DMA.

METHODS We reviewed seven patients treated between January 2013 and August 2015 who received vascularized bone grafts based on the 2nd DMA to reconstruct bone, cartilage, and ligaments. Average age at surgery was 31 years (range, 18 to 54 years). Three different procedures were included: 5 vascularized bone grafts from the 2nd metacarpal base for scaphoid nonunion (Figure 1), 1 vascularized osteo-chondral graft from the capitate for necrosis of the proximal-phalanx head of the long finger, and 1 vascularized bone-ligament-bone (BLB) graft from the 3rd CM joint for scapho-lunate dissociation (SLD) (Figure 2).

RESULTS Of the five scaphoid nonunions, four proximal-pole nonunions received vascularized bones on the dorsal side, and the one waist nonunion received the graft on the volar side. Nonunion sites were fixed with headless compression screws, and bone grafts were fixed with mini screws. Solid bone union was obtained in all cases. To reconstruct the head of the proximal phalanx in the sixth patient, an osteo-chondral flap from the capitate was elevated as a reverse-flow pedicle flap and was grafted to the bone-and-cartilage defect. However, the incongruity of the reconstructed proximal-phalanx head eventually resulted in an ankylotic PIP joint. In the last patient, to reconstruct the SLD, the 3rd metacarpal, dorsal capsular ligament, and capitate were elevated en-bloc and placed as a BLB graft. At final followup, the scapho-lunate interval was sufficiently stabile and scapho-lunate angle was normal.

SUMMARY POINTS  A vascularized bone graft based on the 2nd DMA can be harvested from the 2nd metacarpal base [1], from the capitate as an osteo-chondral graft [2], or from the 3rd CM joint as BLB graft [3].  For scaphoid nonunions, the pedicle is long enough to allow grafting bone on both the dorsal and volar side, depending on the location of nonunion.  Obtaining sufficient joint congruity in an osteo-chondral graft from the capitate is difficult when the defect exceeds half of the proximal-phalanx head. Therefore, the indication for this graft should be limited to defects less than half of the joint surface.  BLB graft from the 3rd CM joint preserves vascularity, provides reasonably early bone union, and maintains ligament strength; however, long-term followup for more patients is necessary to confirm efficacy.

REFERENCES 1. Makino M: Vascularized metacarpal bone graft for scaphoid non-union and Kienböck’s disease. J Reconstr Microsurg 16: 261–267, 2000 2. Zhang Xu: Osteoarticular pedicle flap from the capitate to reconstruct traumatic defects in the head of the proximal phalanx. J Hand Surg 37A:1780–1790, 2012 3. Harvey EJ: A vascularized technique for bone-tissue-bone repair in scapholunate dissociation. Tech Hand Up Extrem Surg 10: 166 –172, 2006

FIGURES

Guest Society Poster 37: Percutaneous Fixation for Scaphoid Nonunion with Bone Grafting through the Distal Insertion Hole of a Fully Threaded Headless Screw

AUTHORS Soichi Ohta, MD, PhD Ryosuke Ikeguchi, MD, PhD Yukitoshi Kaizawa, MD Hiroki Oda, MD Hirofumi Yurie, MD Shuichi Matsuda, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Hand and Wrist Reconstruction PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Percutaneous fixation with bone grafting through the screw insertion hole for scaphoid nonunion has received little attention, although it minimizes damage to the surrounding tissues. Our hypothesis was that retrograde percutaneous fixation with curettage and bone grafting through the distal insertion hole of a fully threaded headless screw will provide excellent results in the treatment of scaphoid cystic nonunions.

METHODS Ten scaphoid cystic nonunions without sclerosis were treated, including one revision case. All nonunions were located in the middle third of the scaphoid. The mean maximum longitudinal length of the bone defect was 4.3 mm. The mean patient age at operation was 24.7 years, and the mean interval between fracture and nonunion surgery was 8.8 months. In the revision case, the interval between the primary and the revision surgery was 6 months. The surgical technique included use of a guidewire and a second derotaion wire inserted percutaneously into the scaphoid tuberosity and then advanced to the proximal pole of the scaphoid with the wrist in an extended and ulnar-deviated position. A cannulated drill was passed over the guidewire, stopping at the distal end of the cystic lesion. The guidewire was then removed. Curettage inside the cystic lesion was performed using a small curette inserted through the distal insertion hole. Bone graft was harvested percutaneously from the iliac crest with a bone biopsy needle and inserted into the cystic lesion through the drill hole of the distal scaphoid fragment. The removed guidewire was reinserted into the previously drilled hole followed by insertion of a selected fully threaded headless screw. After the operation, the wrist was immobilized in a thumb spica cast for the initial 6 weeks, followed by splinting until bone union was confirmed.

RESULTS The mean follow-up period was 12.1 months. Radiologically, union was achieved at an average of 12 weeks postoperatively. At the final follow-up, there was significant improvement in wrist extension movement (from 65.8° to 80.8°) and grip strength (from 65.5% to 87.8% of the unaffected side). Nine patients were free of pain, and one experienced mild pain only during heavy manual labor. The mean VAS, qDASH, and Cooney wrist scores were 0.1, 1.75 and 98.5, respectively.

SUMMARY Retrograde percutaneous fixation with bone grafting through the distal insertion hole of a fully threaded headless screw is a promising option for surgical treatment of scaphoid nonunions without sclerosis. There was significant improvement in the wrist extension range of movement and grip strength.

Guest Society Poster 38: Short Term Outcomes of Distraction Arthroplasty Using External Fixator for Contracture of Proximal Interphalangeal Joint

AUTHORS Hideyuki Ota, MD PhD Atsuhiko Murayama, MD Hiroki Yajima, MD, PhD Kentaro Watanabe, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Hand and Wrist Reconstruction PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Our hypothesis is that distraction arthroplasty is a safe and reliable procedure, and therefore, an option for treating contracture of the proximal interphalangeal (PIP) joint. To verify our hypothesis, we analyzed the outcome of distraction arthroplasty using an external fixator for contracture of the PIP joint.

METHODS We retrospectively assessed the outcome of distraction arthroplasty using an external fixator for the PIP joint. We used the “Global hinge type Illizarov external fixator” for 7 fingers and “PIP wing” for 4 fingers. Between April 2013 and January 2016, 10 consecutive patients (11 PIP joints) with a mean age of 32 years (range, 22–42 y) were treated with external fixation for chronic flexion or extension contracture of the PIP joint resulting from trauma. The duration of joint distraction was 39 days (range, 16–74 d). The patients were followed up for a mean period of 10 months (range, 6–24 mo). We assessed the pre- and post-operative range of motion, total arc of motion, DASH score, and Hand20 score. We divided the patients into a flexion contracture group (6 cases) and an extension contracture group (5 cases) and compared them. The statistical significance between the groups was analyzed with the Mann- Whitney U test and Fisher exact test.

RESULTS The average gain in the range of motion was 37° (pre-operative 27° to post-operative 64°), which was significant (p<0.05). The average gain in the DASH and Hand20 scores was 17 points (pre- operative 22 points to post-operative 5 points) and 19 points (pre-operative 28 points to post- operative 9 points), respectively, which was significant (p<0.05). No loss of motion was observed on the latest follow-up. The average gain in the extension contracture group was slightly better than that in the flexion contracture group (p=0.21). Therefore, it is important to keep the PIP joint extended, for safety position.

SUMMARY POINTS  Distraction arthroplasty using an external fixator is a simple and effective treatment option for chronic traumatic PIP joint contractures with good predictable short term results.  Average gain in the extension contracture group was slightly better than that in the flexion contracture group.  The PIP joint must be kept extended as that is a safe position.  Distraction arthroplasty is an option to treat PIP contracture.

REFERENCES 1. Ghidella SD, Segalman KA, Murphey MS. Long-term results of surgical management of proximal interphalangeal joint contracture. J Hand Surg Am. 2002;27(5):799-805. 2. Abbiati G, Delaria G, Saporiti E, Petrolati M, Tremolada C. The treatment of chronic flexion contractures of the proximal interphalangeal joint. J Hand Surg Br. 1995;20(3):385-9. 3. Hogan CJ, Nunley JA. Posttraumatic proximal interphalangeal joint flexion contractures. J Am Acad Orthop Surg. 2006;14(9):524-33. 4. Houshian S, Chikkamuniyappa C, Schroeder H. Gradual joint distraction of post- traumatic flexion contracture of the proximal interphalangeal joint by a mini-external fixator. J Bone Joint Surg Br. 2007;89(2):206-9. 5. Houshian S, Jing SS, Chikkamuniyappa C, Kazemian GH, Emami-Moghaddam-Tehrani M. Management of posttraumatic proximal interphalangeal joint contracture. J Hand Surg Am. 2013;38(8):1651-8. 6. Kawakatsu M, Ishikawa K, Terai T, Saito S. Distraction arthrolysis using an external fixator and flexor tenolysis for proximal interphalangeal joint extension contracture after severe crush injury. J Hand Surg Am. 2010;35(9):1457-62. 7. Sprague BL. Proximal interphalangeal joint contractures and their treatment. J Trauma. 1976;16(4):259-65. 8. Yang G, McGlinn EP, Chung KC. Management of the stiff finger: evidence and outcomes. Clin Plast Surg. 2014;41(3):501-12. 9. Mizuseki T, Tsuge K, Ikuta Y. Distraction arthrolysis for PIP joint contracture using an external fixator. Tech Hand Up Extrem Surg. 1999;3(1):58-65. 10. Houshian S, Schrøder HA. Distraction with external fixator for contractures of proximal interphalangeal joints: good outcome in 10 cases. Acta Orthop Scand. 2004;75(2):225-8.

Guest Society Poster 39: A Free Superficial Palmar Branch of the Radial Artery (SPBRA) Flap for Finger Soft-tissue Reconstruction

AUTHORS Shimpei Ono, MD, PhD Hiroyuki Ohi, MD Rei Ogawa, MD, PhD, FACS

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Hand and Wrist Reconstruction PURPOSE/CATEGORY - Treatment;Surgical Technique;Anatomy LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Functional and aesthetic reconstruction for digital soft-tissue defects can be challenging for plastic surgeons because there may not be enough remaining skin to harvest local flaps around the defect. The aim of this study is to present a clinical case series of free superficial palmar branch of the radial artery (SPBRA) flaps for soft-tissue reconstruction of the finger.

METHODS Free SPBRA flaps were harvested for 11 fingers of ten patients. The average patient age was 38.3 years. The injured fingers included five index fingers, three long fingers, two ring fingers, and one small finger. All the flaps were vascularized by the SPBRA, usually bifurcates from the radial artery 1–2 cm proximal to the distal wrist crease. There were two types of venous drainage systems in the flaps: the concomitant vein of the SPBRA and the subcutaneous vein.

RESULTS All the flaps survived completely, except for two cases of partial necrosis, which healed without additional surgical intervention. All the donor sites were closed primarily without a skin graft. Most of the fingers involved achieved a full range of motion and showed a good contour and color/texture match. Two-point spatial sensory discrimination was recorded for all patients and adequate protective sensation was attained.

SUMMARY The SPBRA flap is large enough to cover large finger defects without sacrificing the major vessels. Providing a thin, pliable, hairless, and well-vascularized skin cover with a perfect color match, the SPBRA flap seems to be a useful solution to overcome the skin coverage dilemma in patients with finger soft-tissue defects.

REFERENCES 1. Kamei K, Ide Y, Kimura T. A new free thenar flap. Plast Reconstr Surg 1993;92:1380-4. 2. Omokawa S, Mizumoto S, Iwai M, Tamai S, Fukui A. Innervated radial thenar flap for sensory reconstruction of fingers. J Hand Surg Am 1996;21:373-80. 3. Lee TP, Liao CY, Wu IC, Yu CC, Chen SG. Free flap from the superficial palmar branch of the radial artery (SPBRA flap) for finger reconstruction. J Trauma 2009;66:1173-9 4. Iwuagwu FC, Orkar SK, Siddiqui A. Reconstruction of volar skin and soft tissue defects of the digits including the pulp: experience with the free SUPBRA flap. J Plast Reconstr Aesthet Surg 2015;68:26-34.

FIGURES

Guest Society Poster 40: Functional Outcomes of the Triple Looped Suture Technique and Early Active Mobilization for Flexor Tendon Injuries in Digits.

AUTHOR Nozomu Kusano, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPICS Hand and Wrist Trauma; Hand and Wrist Reconstruction; Elbow and Forearm Trauma

PURPOSE/CATEGORIES Evaluation/Diagnosis; Treatment; Surgical Technique; Therapy/Rehabilitation; Prognosis/Outcomes

LEVEL OF EVIDENCE: Level 4

HYPOTHESIS It has been reported that the results of flexor tendon repairs are less satisfactory in the thumb and the little finger after early mobilization. The triple looped suture (triple Tsuge suture) technique has enough strength to allow early active mobilization (EAM). We evaluated the clinical outcomes of the triple looped suture (TLS) tenorrhaphy in zones 1, 2, T1 and T2 in individual digits.

METHODS Forty-two FDP and FPL tendons in 41 patients from 1994 to 2015 were repaired with the TLS technique of 4-0 monofilament nylon combined with epitenon sutures of 5-0 or 6-0 monofilament nylon. Six were index, 10 were long, 6 were ring and 10 were little fingers, and 10 were thumbs. Sixteen digits were zone 1, 16 were zone 2, 4 were zone T1 and 6 were zone T2. Mean age at operation was 35.6 (14-63) years. Mean time from injury to surgery was 3.9 (0-22) days. A mean hospital stay was 31 days. Mean follow-up was 8.2 (3.5-29.1) months. Active mobilization was started on the first postoperative day. Thirty-six digits were combined with early passive mobilization. The results were evaluated for zones 1 and 2 with original Strickland criteria and for zones T1 and T2 with Buck-Gramcko criteria at a minimum of 3 months after injury. Statistical analysis for comparison between zones 1 and 2, and among individual fingers was performed by Student’s t-test, and by one-way ANOVA, respectively.

RESULTS Total active motion of the IP joints (TAMIPJs) was 156.6±19.5 (Mean ± SD)° in zones 1 and 2, 158.1±18.8° in zone 1, and 155.0±20.7° in zone 2. The TAMIPJs was not statistically different between zones 1 and 2 (P=0.5). Active IP joint motion of the thumb was 61.3±12.9°. In zones 1 and 2, 94 percent and 84 percent of the tendons rated excellent to good and excellent, respectively. In zones T1 and T2, all tendons rated excellent. There were no tendon ruptures (Table 1). Both TAMIPJs and percent TAMIPJs values were not statistically different among individual fingers (P=0.53 and P=0.9, respectively, Table 2).

SUMMARY POINTS  This study did not indicate that the results of tenorhaphy are less satisfactory in the thumb and the little finger after EAM.  Our results both in zones 1, 2, T1 and T2 are similar to the best results that have ever been reported.  Excellent clinical outcomes indicate that the TLS technique is reliable technique for EAM.

REFERENCES 1. Kusano N, Yoshizu T, Maki Y. Experimental study of two new flexor tendon suture techniques for postoperative early active flexion exercise. J. Hand Surg, 24B: 152-156, 1999. 2. Okubo H, Kusano N, Kinjyo M, Horikiri K, Futenma C, Kanaya F. Influence of Different Length of Core Suture Purchase between Each Suture Row on the Strength of Six-Strand tendon Repairs. Hand Surg 20: 19-24, 2015.

FIGURES

Guest Society Poster 41: Trapezial Resection Suspensionplasty with Abductor Pollicis Longs Tendon for Thumb Basal Joint Arthritis: An Average 10.2-Year Follow-Up

AUTHORS Toshiyuki Ishiko, MD, Ph.D Osamu Soejima, MD. PhD Hiroyuki Iida, MD Masatoshi Naito, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPICS Hand and Wrist Trauma; Hand and Wrist Reconstruction; Elbow and Forearm Trauma; Elbow and Forearm Reconstruction; Nerve; Systemic Diseases and Disorders

PURPOSE/CATEGORIES Evaluation/Diagnosis; Treatment;Surgical Technique; Therapy/Rehabilitation; Anatomy

LEVEL OF EVIDENCE: Level 3

HYPOTHESIS The purpose of this investigation was to review the long-term results (average, 10.2 y; minimum, 6 y) with the abductor pollicis longs tendon without tendon interposition for thumb basal joint arthritis. Our clinical and radiographic results were evaluated.

METHODS We evaluated nine patients (2 men, 7 women), including 10 thumbs after trapezial resection suspensionplasty with the abductor pollicis longs tendon without tendon interposition for thumb basal joint arthritis. The outcomes were analyzed subjectively by questionnaire and objectively by clinical and radiographic evaluation. The average follow-up period was 10.2 years.

RESULTS All patients reported excellent or good relief of pain and were satisfied with their operation. Four thumbs had mild pain with opening a cap of a plastic bottle. All thumbs had no pain with writing, buttoning a shirt, turning a key. However, three thumbs complained of difficulty in buttoning a shirt, turning a key. Seven patients (eight thumbs) came to our clinic were examined and had radiographs. Six of the eight thumbs had better grip and pinch strength than the other side. The trapezial resection space disappeared in one thumb and showed significant narrowing in two thumbs. Hyperextension of the MP joint was present in six thumbs at rest and five of them were flexed when using 2kg pinch.

SUMMARY POINTS  Our results demonstrate good pain relief at 10.2 years follow-up and compare favorably with other published reports.  The grip and pinch were maintained in 6 of 8 thumbs. Favorable results were achieved for writing, buttoning shirts, turning keys.  No relationship was found between the narrowing of trapezial resection space, the hyperextension of MP joint and function of the thumb. However, impingement developed on the scaphoid and the proximal end of first metacarpal may cause renewed symptoms.

REFERENCES 1. Soejima O, Hanamura T, Kikuta T, Iida H, Naito M. Suspensionplasty with the abductor pollicis longus tendon for osteoarthritis in the carpometacarpal joint of the thumb. J Hand Surg 2006; 31A: 425-428.

Guest Society Poster 42: Distal Radius Fracture Patients Show Declined Ability of Dynamic Body Balancing

AUTHORS Koji Fujita, MD, PhD Hidetoshi Kaburagi, MD Takashi Miyamoto, MD, PhD Yoshiaki Wakabayashi, MD, PhD Ryuichi Kato, MD, PhD Otsushi Okawa, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;International Perspectives PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 2

HYPOTHESIS Fragility fractures of the distal radius are associated with an increased risk of future hip and spine fracture, thus the importance of body balancing ability and bone quality is well acknowledged for falls and secondary fracture prevention. Here, we assessed the body balancing ability, grip strength and bone quality of patients with distal radius fractures who underwent surgery.

METHODS This study is a prospective multicenter study, approved by IRB. Subjects are 110 women (age > 45-year-old) with distal radius fractures as first fragility fracture, who underwent surgery in registered hospitals from January to December in 2015. Two weeks after surgery, body balancing ability was measured by four methods, Functional Reach Test (FRT), Timed Up and Go test (TUG), 2 Step test (2ST) and Timed Unipedal Stance test with eye open (TUS). 2S is the score equal to the maximum length of double stride divided by own height. Grip strength on the non-fracture side (GS) and bone density (T-score) were also measured at the same time point. Statistical analysis was performed by Student’s t test to compare with Japanese normative values and p < 0.05 was considered as significant.

RESULTS FRT is 30.6 cm in 40s (p = 0.03), 31.1 cm in 50s (p = 0.002), 32.8 cm in 60s (p < 0.001) and 28.5 cm in 70s (p < 0.001). TUG is 7.4 seconds (S) in 50s (p < 0.001), 7.2S in 60s (p = 0.002) and 8.1S in 70s (p = 0.004). 2ST is 1.40 in 40s, 1.52 in 50s (p = 0.003), 1.31 in 60s (p < 0.001), 1.22 in 70s (p < 0.001) and 0.89 in 80s (p = 0.01). TUS was 51S in 60s (p < 0.001). GS was 21.3 kg in 50s, 19.4 kg in 60s and 18.0 kg in 80s. Only 25 % of subjects showed lower T-score than - 2.5.

SUMMARY POINTS  The patients with distal radius fractures in 50s, 60s and 70s showed significantly lower body balancing ability, especially during dynamic motion like FRT, TUG, 2ST. GS was also significantly lower in 50s, 60s and 80s.  75% of patients did not show osteoporotic status. It is compatible with the fact that distal radius fractures tend to be the initial fragility fracture and patients were relatively younger.  The patients with distal radius fractures should be identified as “high risk” of falls and secondary fractures. Intensive training could be effective for fall prevention.

REFERENCES 1. Distal radius fracture is an early sign of general osteoporosis: bone mass measurements in a population-based study 2. Improving evaluation and treatment for osteoporosis following distal radial fractures 3. Is the functional reach test useful for identifying falls risk among individuals with Parkinson's disease? 4. Shorter unipedal standing time and lower bone mineral density in women with distal radius fractures 5. Association between new indices in the locomotive syndrome risk test and decline in mobility: third survey of the ROAD study.

FIGURES

This research was supported by a grant received from ZENKYOREN (National Mutual Insurance Federation of Agricultural Cooperatives)

Guest Society Poster 43: Comparison of Bone Mineral Density in Patients With Extra and Intraarticular Distal Radius Fracture

AUTHOR Takuya Yoda, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Hand and Wrist Trauma;Systemic diseases and disorders PURPOSE/CATEGORY - Evaluation/Diagnosis;Basic Science LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Risk factors for onset of intraarticular distal radius fracture (DRF) is unknown. We hypothesize that the bone mineral density (BMD) of patients with intraarticular DRF are lower than patients with extraarticular DRF.

METHODS Thirty four consecutive patients from 50 to 89 years with DRF are prospectively enrolled. The patients were classified according to AO classification as 19 type A and 15 type C. BMD in their spine, hip and distal radius were measured by dual X-ray absorptiometry. Their body mass index (BMI) were also measured. The BMD and BMI were compared with tape C fracture group and type A fracture group.

RESULTS The mean ages were 69.1 years in the type A group and 71.1 years in the type C group. The mean BMD of spine, hip distal radius were 0.68, 0.54, 0.29 g/cm2 in the type A group and 0.72, 0.54, 0.28 g/cm2 in the type C group. The mean BMI were 21.5 kg/m2 in the type A group and 22.0 kg/m2 in the type C group. There was no significant difference in the two group.

SUMMARY POINTS  DRF is one of the osteoporotic fractures.It is well known that the BMD of distal forearm is significantly lower in DRF patients than in healthy controls.1-2  Although we hyposized that the BMD of intraarticular group are lower than extraarticular group, especially in the ultra distal radius, no significant difference was observed.  There is the possibility that the occurrence of intraarticular fracture is not affected by BMD but bone microarchitecture and loading force.3-4

REFERENCES 1. Mallmin H, Ljunghall S. Distal radius fracture is an early sign of general osteoporosis: bone mass measurements in a population-based study. Osteoporos Int. 1994 Nov;4(6):357-61. 2. Tornetta P 3rd. Intraarticular distal radius fracture. J Orthop Trauma. 2001 Aug;15(6):453-4. 3. Nishiyama KK, Macdonald HM, Hanley DA, et al. Women with previous fragility fractures can be classified based on bone microarchitecture and finite element analysis measured with HR-pQCT.Osteoporos Int. 2013 May;24(5):1733-40. 4. Chevalley T, Bonjour JP, van Rietbergen B, et al. Fracture history of healthy premenopausal women is associated with a reduction of cortical microstructural components at the distal radius.Bone. 2013 Aug;55(2):377-83.

FIGURES

Guest Society Poster 44: Pathogenesis of the Lateral Epicondylitis: Ultrasonographic Analysis

AUTHORS Kunihide Muraoka, MD, PhD Osamu Soejima, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Reconstruction LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Lateral epicondylitis (LEC) is now considered to be a tendinosis, which is defined as a degenerative process(1). There are several surgical procedures for LEC including open, percutaneous, and arthroscopic approach. We have performed mini open surgical treatment in which the extensor carpi radialis brevis (ECRB) origin is removed for patients who failed to respond to non-operative treatment(2). In this surgery, we believe that it is critical to release the tension of the radial head and therefore the capsule with a part of the annular ligament must be resected. In the ultrasound examination of the elbow, radial head showed a medial-lateral movement accompanied by the rotation of the forearm. We hypothesized that the radial head of the patients with LEC has poorer mobility. In this study, we compare the radial head mobility among three groups [normal (control), non-operative (mild LEC), and operative (severe LEC) group].

METHODS Sixteen asymptomatic elbows in 8 patients (control group), 11 LEC elbows in 10 patients responded to non-operative treatment (mild LEC group), and 13 LEC elbows in 12 patients underwent surgical treatment (severe LEC group) were included in this study. Ultrasound examination of each elbow was performed and the lateral shift of the radial head was measured. The lateral shift of the radial head was defined as the migration length of the radial head over the tangential line of the radiohumeral joint accompanied by the forearm rotation (Fig 1). The differences in the mean value of the lateral shift of the radial head among the three groups were determined using a Mann–Whitney U test. Values of P<0.05 were considered statistically significant.

RESULTS The mean value of the lateral shift in the mild LEC group (2.11 mm) were significantly greater than that of in the severe LEC group (1.31 mm) (P<0.05). Although the mean value of the lateral shift in the mild LEC group was greater than that of in the control group (1.36 mm), it has not reached the statistical difference (P=0.064).

SUMMARY In this study, we found that the radial head with the severe LEC tend to have poorer mobility than that with the mild LEC group. This finding support our surgical concept for the sever LEC that it is critical to release the tension of the radial head and therefore not only the ECRB origin but also the capsule and a part of the annular ligament must be resected.

REFERENCES 1. Adams JE, Stainmann SP: Elbow Tendinopathies and Tendon Ruptures. In: Wolfe FW, ed. Green’s OPERATIVE HAND SURGERY. ELSEVIER, Philadelphia. 2011; 923-44 2. Soejima O, Iwamoto R, Matsunaga A: Surgical treatment of lateral epicondylitis; Results of arthroscopic versus open procedures. 19th Annual Congress of the Federation of the European Societies for Surgery of the Hand (FESSH). Paris, France, 2014.06.18-21

FIGURES

Guest Society Poster 45: Preoperative Ultrasound Predicts Fragment Instability in Capitellar Osteochondritis Dissecans

AUTHORS Masaaki Yoshizuka, MD Toru Sunagawa, MD, PhD Yuko Nakashima, MD, PhD Rikuo Shinomiya, MD, PhD Nobuo Adachi, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Reconstruction PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 4

HYPOTHESIS In this study, we examined the correlation between preoperative ultrasonographic (US) findings and intraoperative instability in baseball pitchers with capitellar osteochondritis dissecans (OCD). We hypothesized that certain US findings are characteristic to unstable osteochondral fragment.

METHODS We retrospectively reviewed 30 patients who had undergone both preoperative US evaluation and surgery for capitellar OCD. Intraoperative stability of the fragment was determined according to the International Cartilage Repair Society (ICRS) OCD classification. We excluded seven patients who had either a dislocated fragment or a loose body (ICRS classification grade 4). Of the remaining 23 patients, 11 had stable fragments (stable group=grade 1 or 2), and 12 had unstable fragments (unstable group=grade 3). All preoperative US examinations had been performed with the elbow fully flexed to obtain the posterior longitudinal view and fully extended to obtain the anterior longitudinal view. We reviewed each US findings for the presence of five features: non-circularity of the subchondral bone, irregular contour of the chondral surface, crack in the cartilage, thinning of the cartilage, and thickening of the cartilage. We recorded the proportion of patients in each group that exhibited each of the ultrasonographic features.

RESULTS We observed non-circularity of the subchondral bone in 27% patients of the stable group and in 50% of the unstable group, irregular contour of the chondral surface in none of the patients in the stable group and in 75% patients in the unstable group, cracked cartilage in 18% patients of the stable group and in 75% patients of the unstable group, thinning of the cartilage in 9% patients of the stable group and in 75% patients of the unstable group, and thickening of the cartilage in 55% patients of the stable group and in 17% patients of the unstable group. Based on the US, we defined the fragment as unstable when either irregular contours of the chondral surface or thinning of the cartilage or both were observed and stable when neither of these was observed. LUCL might act a posterior buttress for the radial head and the ulna to prevent its subluxation, and therefore is considered to be the principal constraint of the elbow joint against PLRI. The results of this study may assist surgeons in performing LUCL reconstruction with a more anatomic perspective.

REFERENCES 1. O’Driscol SW, Bell DF, Morrey BF. Posterolateral rotatory instability of the elbow. J Bone Joint Surg Am 1991; 7(3): 440–446. 2. O’Driscoll SW, Horii E, Morrey BF, Carmichael SW. Anatomy of the ulnar part the lateral collateral ligament of the elbow. Clin Anat 1992; 5(4): 296–303. doi: 10.1002/ca.980050406. 3. Mehta JA, Bain GI. Posterolateral rotatory instability of the elbow. J Am Acad Orthop Surg 2004; 12(6): 405–415. 4. Reichel LM, Milam GS, Sitton SE, Curry MC, Mehlhoff TL. Elbow lateral collateral ligament injuries. J Hand Surg Am 2013; 38(1): 184–201. doi: 10.1016/j.jhsa.2012.10.030.

FIGURES

Guest Society Poster 47: Long-Term Outcome of Synovectomy with Radial Head Resection for Rheumatoid Elbow

AUTHORS Masanori Nakayama, MD, PhD Yu Sakuma, MD Tetsuji Hosozawa, MD Hitoshi Imamura Katsunori Ikari, MD, PhD Shigeki Momohara, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Reconstruction PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Synovectomy with radial head resection (synovectomy) for rheumatoid elbow was an effective surgical option and had good long-term outcome.

METHODS We reviewed our surgical results of synovectomy for rheumatoid elbow performed between 1993 and 2005 retrospectively. There were 29 cases with 31 elbows who could be available for follow- up over 10 years. Thirteen were left and 18 were right elbows. Twenty-one of these patients were female and 8 were male. Fourteen elbows were classified as grade 3, 6 as grade 4, and 2 as grade 5 according to Larsen’s classification. Their average age was 52.4 (21-72) years and the average follow-up term was 159 (120 - 261) months. The evaluated items were arc of motion of the elbow, pain at the last examination, existence of surgical revision and radiographic change of carrying angle.

RESULTS The average arc of motion was 86 (45-120) degrees before surgery or 87 (25-130) degrees at the last exam. Nine patients had elbow pain at the last, however, there was only one patient underwent revision surgery. Other patients were very or partially satisfied with only synovectomy and did not hope to undergo revision surgery. In non-revised patients, the average change of carrying angle was 4.3(-8-13) degrees. There were only 4 elbows which had 10 or more degrees change.

SUMMARY POINTS  Nowadays, synovectomy has been considered as palliative surgery to fill up time to total elbow arthroplasty, however, there were only one patient had necessity of surgical revision in this study with observations over 10 years.  Synovectomy might be a good surgical option for rheumatoid elbow and have good long- term outcome.

REFERENCES 1. Koshino T, et al. Surgical techniques of synovectomy with release of muscle insertion and assessment criteria for rheumatoid elbow. Techiques Orthop 1991; 6: 13-8. 2. Ishii K, et al. Good long-term outcome of synovectomy in advanced stages of the rheumatoid elbow 64 elbows followed for 10–23 years. Acta Orthopaedica 2012; 83: 374–8 3. Gendi NS, et al. Synovectomy of the elbow and radial head excision in rheumatoid arthritis. Predictive factors and long-term outcome. J Bone Joint Surg Br 1997; 79:918- 23.

Guest Society Poster 48: Biomechanical Properties of an Orthogonal Plate Versus a Parallel Plate Using the Same Locking Plate System for Intra-Articular Distal Humerus Fractures Under Radial or Ulnar Column Axial Load

AUTHORS Akira Hara, MD Toshiya Kudo, MD Satoshi Ichihara, MD, PhD Yasuhiro Yamamoto, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma PURPOSE/CATEGORY - Basic Science LEVEL OF EVIDENCE: N/A

HYPOTHESIS Parallel plating may be biomechanically superior to orthogonal plating in each column of the elbow (radial and ulnar) when using a the same plating system and a double plate fixation method.

METHODS We used artificial bone to make an AO type 13-C2.3 intraarticular fracture model with a 1cm gap at the supracondylar level.

We used anatomically preshaped distal humerus plates (LCP DHP, Synthes GmbH, Solothurn, Switzerland). Although this construct is originally orthogonal, we created a mediolateral parallel configuration to use a contralateral medial plate instead of a posterolateral plate from the LCP DHP system.

An axial load was applied to the radial column and ulnar column respectively from 0N to 200N. We calculated the stiffness of the radial column and the ulnar column, and the fragment displacement by means of two methods, one was the shortening of the supracondylar gap in the AP view and the other was the anterior movement of the condylar fragment in the lateral view. Data was analyzed using the unpaired student t test.

RESULTS In the medial column, there were no significant differences between the two groups(127.0±12.8 N/mm in orthogonal and 139.2±19.6 N/mm in parallel). However, in the radial column compressive stiffness, the parallel configuration (159.4±27.7 N/mm) was superior to the orthogonal configuration (96.3±8.6 N/mm). Anterior movement of the capitellum during axial load of the radial column, demonstrated significant differences between 5.2±1.2 degrees in the orthogonal configuration and 1.1±1.0 degree in the parallel configuration. The decrease of radial column stiffness in the orthogonal configuration was due to the posterolateral plate bending in the anterior direction. Interdigitation of the bone fragments had no influence on the ulnar axial stiffness in this study.

SUMMARY POINTS  The capitellum and trochlea have 30 degrees of anterior flexion to the humeral shaft. Therefore axial compression induced an anterior bending force on the capitellum and the trochlea.  In our study the posterolateral plate tends to bend anteriorly under axial compression in comparison with the medial or the lateral plate.  We supposed in the orthogonal configuration the axial compression induced more anterior displacement of the capitellum than of the trochlea, which finally induces secondary fragment or screw dislocation on the posterolateral plate, or nonunion at the supracondylar level.  In the parallel configuration the anterior movement of the capitellum or trochlea was restricted due to angular stability of the plate and locking screws in the condyle.

REFERENCES 1. Korner J, Lill H, Muller LP, et al. Osteoporos Int 2005: 16: S73-79. 2. O'Driscoll SW. J Shoulder Elbow Surg 2005: 14: 186S-194S

FIGURES

Guest Society Poster 49: Morphologic Analysis of Common Extensor Tendon Using Magnetic Resonance Imaging with Fast Imaging Employing Steady-State Acquisition (FIESTA) in Recal

AUTHORS Koichi Sasaki, MD Takuro Wada, MD Kousuke Iba, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Magnetic resonance imaging findings in recalcitrant lateral epicondylitis shows increased T2- weighted signal intensity of the common extensor tendon(Ref_1). Fast imaging employing steady-state acquisition (FIESTA) sequence is one of the steady-state coherent MRI imaging sequences. FIESTA achieves a high contrast-to-noise ratio with few flow artifacts. It enables acquisition of thin slices and provides submillimetric spatial resolution and high contrast resolution. Using FIESTA sequence, we will understand in depth the pathology of the common extensor tendon. We hypothesized that FIESTA sequence will detect the common extensor tendon tear in recalcitrant lateral epicondylitis with high sensitivity and specificity.

METHODS Thirteen patients (7 women, 6 men; mean age, 51 years) with recalcitrant lateral epicondylitis, who underwent arthroscopic surgery with preoperative MRI studies between 2010 and 2015, were reviewed retrospectively. FIESTA sequences at coronal, sagittal, and axial sections were obtained. MRI findings of the common extensor tendon was classified into 2 types, namely, Type A and Type B. Type A showed equal signal intensity of the tendon and joint effusion. Type B showed a significantly lower signal intensity of the tendon compared with the joint effusion. For arthroscopic diagnosis of capsular tear, we regarded longitudinal and complete capsular tear at the undersurface of the ECRB tendon (Baker types II and III lesions) as present but capsular flare (Baker type I lesion) as absent. Preoperative MRI and arthroscopic findings were compared.

RESULTS In FIESTA sequence MRI, 4 cases were type A and 9 cases were type B. Arthroscopy confirmed 5 of 13 elbows with capsular tears ( type II-3; type III-2) at the undersurface of the ECRB tendon and 8 type I lesions. There was a significant correlation between the MRI findings and Baker’s classification. MRI predicted arthroscopic capsular tear with 100% sensitivity and 89% specificity.

SUMMARY MRI with FIESTA sequence detected the capsular tear in patients with recalcitrant lateral epicondylitis with high sensitivity and specificity compared with our previous report (Ref_2). FIESTA sequence is applicable for the diagnosis of recalcitrant lateral epicondylitis.

REFERENCES 1. Magnetic resonance imaging findings of refractory tennis elbows and their relationship to surgical treatment.Aoki M, Wada T, Isogai S, Kanaya K, Aiki H, Yamashita T.J Shoulder Elbow Surg. 2005;14:172-7. 2. The detection of the capsular tear at the undersurface of the extensor carpi radialis brevis tendon in chronic tennis elbow: the value of magnetic resonance imaging and computed tomography arthrography. Sasaki K, Tamakawa M, Onda K, Iba K, Sonoda T, Yamashita T, Wada T. J Shoulder Elbow Surg. 2011;20:420-5

FIGURES

Guest Society Poster 50: Prognostic Factors of Open Arthrolysis for the Stiff Elbow

AUTHORS Hiroo Kimura, MD Takuji Iwamoto, MD, PhD Sanae Irimura, MD Takeshi Hagiwara, MD Kensuke Ochi, MD,PhD Kazuki Sato, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma PURPOSE/CATEGORY - Prognosis/Outcomes LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Open arthrolysis for the stiff elbow has been widely performed. However, there remain a considerable number of cases in which we are unable to gain a functional arc of motion. The purpose of this study was to identify the prognostic factors that affect surgical outcome using multiple logistic regression analysis.

METHODS We performed a retrospective review of all patients who underwent open arthrolysis for the stiff elbow between 2002 and 2014. Of 66 cases of open arthrolysis, 36 cases which were followed for a minimum period of 1 year were included in this study. Twenty-seven cases were male and 9 cases were female. Twenty cases were posttraumatic arthritis and 16 cases were osteoarthritis. The average age at the time of surgery was 41 (range 7-64) years. Patients’ records were reviewed for the following factors: age, sex, smoking, body mass index (BMI), cause of contracture, associated nerve injury, and elbow range of motion (ROM) before surgery. Univariate analyses were performed to evaluate the associations between prognostic factors and postoperative ROM by Mann-Whitney U test, Pearson correlation coefficient test or Welch’s t test. We then classified the patients into two groups according to postoperative ROM. Good cases had active flexion of >120 degrees and active extension of >-30 degrees, and the other cases were categorized as poor. Multiple logistic regression analysis was conducted to identify the association between poor results and selected prognostic factors.

RESULTS Preoperative ROM was -27 degrees of extension and 94 degrees of flexion on average. Postoperative ROM was -20 degrees of extension and 120 degrees of flexion on average, showing significant improvement (p<0.01). Univariate analysis showed there to be a significant association between the preoperative ROM and the postoperative ROM. There were 15 poor outcome cases, of which 9 cases were posttraumatic arthritis and 6 cases were osteoarthritis. Multiple logistic regression analysis showed the independent risk factors for poor outcome were preoperative ROM (odds ratio 0.92, p<0.01), BMI (odds ratio 0.61, p<0.05) and posttraumatic arthritis (odds ratio 34.7, p<0.05).

SUMMARY Our results suggested that surgical result of open arthrolysis for the stiff elbow is influenced by preoperative ROM, low BMI and posttraumatic arthritis.

Guest Society Poster 51: Ulnar Corrective Osteotomy Using the External Fixator ‘Multiplanar MiniRail' for Pediatric Patients with Chronic Radial Head Dislocation

AUTHORS Yuya Ohtake, MD Kenji Onuma, MD, PhD Tomonori Kenmoku, MD, PhD Koji Sukegawa, MD, PhD Hisako Fujimaki, MD Masashi Takaso, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Although corrective ulnar osteotomy is currently used to treat chronic Monteggia fractures with radial head dislocation, the best way to correct and stabilize the reduction remains controversial. We present our treatment method using the external fixator MultiPlanar MiniRail (M2) to correct and stabilize the ulna osteotomy.

METHODS We reviewed five patients with chronic radial head dislocation, due to Monteggia fracture in four and congenital in one (case 4 in table 1), who underwent corrective ulnar osteotomy using external fixation with M2 (Figure 1). One patient (case 2) was retreated following initial corrective osteotomy of the ulna using plate fixation. Average age was 8.8 years and the average duration to operation after fracture was 4.0 months. We treated four of the five patients with open reduction of the radial head, full release of the capsular contracture, removal of fibrous scar tissue within the joint, ulnar osteotomy, and fixation of the osteotomy site with an M2 external fixator. One patient was treated with closed reduction of the radial head, ulnar osteotomy, and fixation of the osteotomy site with an M2 external fixator. Clinical and radiographic follow-up averaged 10.2 months. Descriptive statistics utilized Student’s t-test to compare the preoperative and postoperative range of motion of the elbow.

RESULTS All five patients had a good clinical outcome without delayed union at the osteotomy site. All patients maintained reduction of the radial head at final follow-up. Mean degree of preoperative and postoperative flexion/extension of the elbows was 109/-2, and 138/0 degrees, respectively. Mean degree of flexion was significantly higher on postoperative examination than on postoperative examination (Table 1).

SUMMARY POINTS  External fixation using the MultiPlanar MiniRail has the major advantage of permitting and capturing the optimal position of the ulna osteotomy which achieves the best possible reduction of the radial head.  Further advantages compared to plate fixation are that the angle of the ulnar osteotomy site can be easily changed by adjustment of the fixator, the surgery is less invasive, and a removal operation under general anesthesia is unnecessary.  We conclude that our procedure for corrective ulnar osteotomy with the M2 external fixator is an effective option in the management of children with radial head dislocation.

FIGURES

Guest Society Poster 52: Prone Positioning for the Fixation of Medial Humeral Epicondyle Fractures in Children

AUTHORS Takaaki Saigo, MD Kotaro Sato, MD Karen Tokunaga, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Placing patients prone for the fixation of pediatric medial epicondyle fractures offers advantages over traditional supine positioning.

METHODS Thirteen patients operated on for a displaced medial epicondylar fracture between 2009 - 2015 were prospectively divided into surgery in the supine and prone positions. In the supine group, the average age of the patients was 11.8 years (range 10-13 years, 3 males and 2 females, at a mean of 6.8 months of follow up). In the prone group, the average age of the patients was 11.9 years (range 8-15 years, 4 male and 4 female, at a mean of 6.1 months of follow up). Indications for both groups for operative treatment were displaced medial epicondyle fracture or medial epicondyle fracture with an associated elbow dislocation. The medial epicondylar fragment was anatomically reduced and fixed with tension band wiring in 12 cases and a compressive screw was used in 1 case. Postoperative malreduction, union rate, postoperative neurological complications, operation time and functional outcome were analyzed. Functional outcomes were assessed using a scoring system based on the Flynn functional score. The t-test was used to compare the operation time of the two groups.

RESULTS In the supine group, there were no intraoperative or postoperative complications. Mean operation time was 64.6 minutes. Union was achieved in all cases. Postoperative malreduction (>2mm) was apparent in 3 cases. Functional score was excellent in 4 elbows and good in 1 elbow. In the prone group, there were no intraoperative or postoperative complications. Mean operation time was 52.3 minutes. The fracture was easily reduced without having to pull excessively on the fragment. Union was achieved in all cases. There were no cases of postoperative malreduction (>2mm). Functional scores were excellent in 7 elbows and fair in 1 elbow. The mean operation time was about 10 minutes shorter in the prone than in the supine positions but this was not significant.

SUMMARY No significant differences were found in objective outcome measures between the two groups. However, we think the prone positioning patients aided in the reduction of the fragment with equivalent results to the traditional supine technique.

REFERENCES 1. Alternative technique for open reduction and fixation of displaced pediatric medial epicondyle fractures. J Child Orthop (2012)

Guest Society Poster 53: The Operative Treatment for Dubberley Type 3B Coronal Shear Fractures of the Distal Humerus

AUTHORS Shunsuke Nishimoto, MD, PhD Mitsuru Horiki, MD, PhD Reiko Nakagawa, MD Kakurou Denno, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Dubberley type 3B coronal shear fractures involving fractures of both the capitellum and the trochlea as separate fragments and posterior condylar comminution are rare, complex fractures that can be technically challenging to manage. We examined the clinical outcomes of 6 patients with Dubberley type 3B fractures that underwent open reduction and internal fixation, because there is no consensus for the operative treatment of Dubberley type 3B.

METHODS Six patients were all female, with an average age of 65.8 years and an average follow-up of 9.7 months. Posterior approach with olecranon osteotomy was used in all cases. Headless compression screw fixation (DTJ screws; MEIRA) was done in 3 cases, and double plating method using anatomical locking plate (LCP- distal humeral plate; Depuy Synthes) was done in 3. Artificial or autologous bone graft was added as needed. Patient outcomes were assessed with radiographic and CT examination, range-of-motion measurements and Mayo Elbow Performance score at the time of final observation.

RESULTS The mean range of flexion was 129° with a mean extension of -21°. Radiographically, one patient used headless compression screw fixation had a nonunion, and one patient used anatomical locking plate fixation had avascular necrosis. In the patient with nonunion, extension limit was remained. According to the Mayo Elbow Performance score, the results were excellent in all patients using anatomical locking plate. On the other hand, the results were good in two patients using headless compression screw and were fair in a patient with nonunion using headless compression screw.

Dubberley type 3B fractures had a significantly higher rate of nonunion than the other types. Therefore, it is conceivable that the stable fixation is required. Furthermore, while the capitellum alone does not contribute to elbow stability, the trochlea has an important role. Accordingly, the hard fixation including the trochlea is important. Anatomical locking plates have the stability for angulation and are able to fix more firmly compared with headless compression screws. Anatomical locking plates are useful for treatment of Debberley type 3B coronal shear fracture of the distal humerus.

SUMMARY POINTS  Debberley type 3B coronal shear fractures are rare injuries with articular complexity, and there is no consensus on the optimal method of fixation.  Debberley type 3B had a significantly higher rate of nonunion than other types.  Anatomical locking plates are useful for Debberly type 3B fractures.

Guest Society Poster 54: Clinical Results of Supracondylar Humeral Fractures in Children; Comparison Between Closed and Open Reduction Followed by Percutaneous Pinning

AUTHOR Yuji Tomori, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 3

HYPOTHESIS To compare the clinical outcomes of two procedures, closed or mini-open reduction followed by percutaneous pinning , for the supracondylar fractures of the humerus in children.

METHODS Between 2004 and 2013, children with supracondylar fractures of the humerus who had undergone surgery were identified. Case records and X-ray of 34 patients were reviewed. Twenty-one patients had undergone close reduction followed by percutaneous pinning (CRPP). And thirteen patients had undergone mini-open reduction with anterior approach followed by percutaneous pinning (m-ORPP). The average age of the patients at the time of surgery was 5.4 (1-13) year-old in CRPP-group, and 5.4 (2-9) year-old in m-ORPP-group. On the basis of the Gartland classification, twelve were type 2 and nine were type 3 in the CRPP-group, and 4 were type 2 and 9 were type 3 in m-ORPP-group. The patients were subsequently followed up at 8 (3- 21) months in CRPP-group and 10 (3-10) months in m-ORPP-group after surgery. Postoperative complications, the imaging evaluation of radiograph, clinical evaluation, including range of motion (ROM) and Flynn’s criteria, were investigated. To evaluate the deformity of the humerus, Baumann’s angle (BA) and carrying angle (CA) were calculated on the anteroposterior radiographs.

RESULTS Although none of patients showed loss of reduction, deep infection, or neuro-vascular complications, one patient had a cubitus varus deformity in CRPP-group. When comparing CA of the contra-lateral side, the average angle of the CA loss was significantly larger for CRPP- group than for m-ORPP-group. According to Flynn’s criteria, there were 12 excellent, 8 good and 1 poor result, in CRPP-group. In tem-ORPP group there were 12 excellent and 1 good result.

SUMMARY To eliminate the possibility of the postoperative cubitus varus deformity, the mini-open reduction followed by percutaneous pinning would be a reliable and less-invasive procedure for the supracondylar fractures of the humerus in children.

REFERENCES 1. Kasser JR, Beaty JH. Supracondylar fractures of the distal humerus. In: Beaty JH, Kasser JR, Wilkins KE, Rockwood CE, editors. Rockwood and Wilkins’ Fracture in Children. 6th ed. Philadelphia: Lippincott Williams & Wilkins. 2006;543-89. 2. Goldfarb CA, Patterson JM, Sutter M, Krauss M, Steffen JA, Galatz L. Elbow radiographic anatomy: measurement techniques and normative data. J Shoulder Elbow Surg. 2012;21:1236-1246. 3. Flynn JC et al: Blind pinning of displaced supracondylar fractures of the humerus; sixteen years's experience with long term follow up. J Bone Joint Surg. 1974;56-A:263- 272. 4. Sawaizumi T et al: Surgical technique for supracondylar fracture of the humerus with percutaneous leverage pinning. J Shoulder Elbow Surg. 2003;12:603-606. 5. Omid R, Choi PD, Skaggs DL. Supracondylar humeral fractures in children. J Bone Joint Surg Am. 2008;90:1121-1132.

FIGURES

Guest Society Poster 55: Medial Ulnar Collateral Ligament Rupture Was Highly Associated With Pediatric Medial Epicondyle Fracture In Surgery

AUTHORS Yoshihiko Satake, MD Yuji Tomori, MD Mitsuhiko Nanno, MD Norie Kodera Yusuke Hagiwara Shinro Takai, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Elbow and Forearm Trauma;Congenital and Pediatric PURPOSE/CATEGORY - Evaluation/Diagnosis;Treatment;Prognosis/Outcomes LEVEL OF EVIDENCE: Level 4

HYPOTHESIS It is generally considered that medial ulnar collateral ligament (MUCL) rupture is rare in children with medial epicondyle fractures. The purpose of this study was to investigate the incidence of valgus instability after internal fixation and the rate and area of MUCL rupture in pediatric medial epicondyle fractures without postero-lateral instability.

METHODS Sixteen children were surgically treated in our hospital between 2003 and 2014. There were ten male and six female patients. The mean age at the time of injury was 10.4 years. Twelve elbows were classified as Watson-Jones type2, 3 were type3, and 1 was type4. In every patient, operative treatment consisted of open reduction and internal fixation with tension band wiring. Valgus instability was evaluated before internal fixation and after fixation under general anesthesia. The rate and area of MUCL rupture was examined under direct vision. Mayo Elbow Performance Score was evaluated at final follow-up.

RESULTS Valgus instability before fixation appeared in 9 children, notably in all the children with Watson- Jones type3 and 4. The injury area was the anterior band of the MUCL. MUCL rupture occurred in 2 children (12.5%). Valgus instability after fixation remained in 3 patients: two cases were of MUCL rupture, and the other case was of a small fragment attached to the intact MUCL, separated from except for the medial epicondyle fragment attached to the pronator mass. Stability was achieved for these 3 patients after repair of the MUCL and fixation of the fragment with MUCL. At final follow-up, Mayo Elbow Performance Score was 98.9 points.

SUMMARY POINTS

 This is the first report to investigate the incidence of valgus instability and the rate and area of MUCL rupture with medial epicondyle fracture in children.  The incidence of medial ulnar collateral ligament rupture accounted for 12.5% of medial epicondyle fractures in the children in this study.  Valgus instability remained after fixation in all patients with ruptured MUCL.  Stability was achieved after repair of MUCL and fixation of fragment with intact MUCL.

REFERENCES 1. Pathy R, Dodwell ER. Medial epicondyle fractures in children. Curr Opin Pediatr. 2015; 27:58-66. Review. 2. Biggers MD, Bert TM, Moisan A, Spence DD, Warner WC Jr, Beaty JH, Sawyer JR, Kelly DM. Fracture of the Medial Humeral Epicondyle in Children: A Comparison of Operative and Nonoperative Management. J Surg Orthop Adv. 2015 ;24:188-92. 3. Louahem DM1, Bourelle S, Buscayret F, Mazeau P, Kelly P, Dimeglio A, Cottalorda J. Displaced medial epicondyle fractures of the humerus: surgical treatment and results. A report of 139 cases. Arch Orthop Trauma Surg. 2010 ; 130: 649-55. 4. Atul KF, Baldwin K, Hornef H, Hosalkar HS. Operative versus nonoperative management pediatric medial epicondyle fractures: a systematic review. J Child Orthop 2009; 3:345–357. 5. Long-term results of treatment of fractures of the medial humeral epicondyle in children. Farsetti P, Potenza V, Caterini R, Ippolito E. J Bone Joint Surg Am. 2001; 83: 1299-305. 6. Beaty JH, Kasser JH. Beaty JH, Kasser JR. The elbow-physeal fractures, apophyseal injuries of the distal humerus, osteonecrosis of the trochlea, and T-condylar fractures. Rockwood & Wilkins’ fractures in children. Philadelphia, PA: Lippincott Williams & Wilkins; 2005. 628–642. 7. Fowles JV, Slimane N, Kassab MT. Elbow dislocation with avulsion of the medial humeral epicondyle. J Bone Joint Surg Br 1990; 72:102–104.

Guest Society Poster 56: Thumb Deformity Associated With Ring Chromosome 4

AUTHORS Yoko Kishi, MD,PhD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Congenital and Pediatric LEVEL OF EVIDENCE: Level 4

HYPOTHESIS The objective of this study was to clarify the difference in thumb deformity between our case with ring chromosome 4 and thumb polydactyly, in which ulnar side was small and had no active motion, and other cases of ring chromosome 4, by analyzing previous reports.

METHODS A total of 39 cases of ring chromosome 4 from 1969 to 2010 in previous reports were collected and data on thumb deformities were analyzed. Our case had bilateral atypical thumb polydactyly, which was classified as type 4 on the right side and type 5 on the left side, according to the Japanese Society for Surgery of the Hand: Modified International Federation of Societies for Surgery of the Hand classification. She also had intrauterine growth retardation, arterial septal defect and patent ductus arteriosus, spina bifida occulta and clinodactyly of both little fingers. A chromosome analysis was performed, which showed mosaic 46,xx,r(4)(p16.3 q35)[21]/45,xx.- 4[9]. The area of 4p16.3 (Wolf–Hirschhorn syndrome) was normal as assessed by the FISH method.

RESULTS Of the 39 cases, 20 (51.3%) had thumb deformities. Among them, 19 cases (95%) showed radial ray deficiency and only 1 case (5%) showed bilateral thumb polydactyly but the details were not described. Clinodactyly was seen in 5 cases (12.8%). Foot deformities were present in 6 cases (15.4%). The phenotype of our case is very rare because only 2 cases were found in the literature and they discussed about thumb polydactyly with and without chromosomal deformities. Tamura found that the responsible gene of thumb polydactyly existed between 4q32-q36. He explained that the difference in phenotype was caused by the amount of the responsible genes. Nagoya explained that phenotype variation in ring chromosome 4 existed because the ring chromosome 4 is very fragile, even though the break point is the same.

SUMMARY POINTS  Over 50% of ring chromosome 4 patients had radial ray deficiency.  Our case is the second report of thumb polydactyly in ring chromosome 4.  This study showed the quite rare deformity in thumb polydactyly without active motion on the ulnar side.

REFERENCES 1. Dominguez M.G et al:Variated-like mosaicism and ring syndrome in a r(4)boy, appraisal of 38 patients with a fairly complete ring 4.Genetic Counseling:2010;21,4,411-421 2. Urina-Gomez C.E.et al:Correlation between cytogenetic fluorescence in situ hybridization and clinical findings in two cases of ring chromosome 4.Am.J.Hum.Genet.,2002.71.300 3. Hasegawa K.et.al:Thumb polydactyly with a floating ulnar thumb,Acta Med.Okayama.2013.67.6.391-395

FIGURES

Guest Society Poster 57: Bone Lengthening for Congenital Hand Anomalies with Use of Ilizarov Mini-Fixator

AUTHOR Keita Yamada, MD

The author of this poster has nothing of financial value to disclose.

CURRICULUM TOPIC - Congenital and Pediatric PURPOSE/CATEGORY - Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS There are many reports describing the technique of callus distraction in the treatment of brachydactyly, symbrachdactyly, Apert and Pfeiffer hand. However, surgical indication and timing of operation still need to be discussed. Ilizarov mini fixator is an external bone fixator consisting of small pins with a diameter of 1.2mm each. It originally was designed by Ilizarov research institute and manufactured in Japan under authorization of the institute. The aim of this study is to investigate the indication and benefit of this device especially in bone lengthening of hypoplastic phalanges.

METHODS Between 2012 and 2015, the treatment with Illizarov mini fixator in order to lengthen the phalanges was examined in 14 patients with congenital hand anomalies. Consisting of 5 cases of brachydactyly, 3 cases of congenital band syndrome, and 1 case each of thumb hypoplasia, Apert hand, polydactyly of the thumb, symbrachydactyly, and clinodactyly respectively. Timing of surgery ranged from 1 year to 15 years of age with a mean of 7.4 years. The planned rate of elongation was 0.5mm/day, and distraction was continued until the ideal length of the bone was achieved.

RESULTS The device was removed at a mean of 75 days after surgery. Complications consisted of bone fracture in 3 fingers, and loosening of wire in 2 fingers, pin site infection, malunion, and pseudoarthrosis in 1 finger respectively. On average, the bones were lengthened 9.4 mm with a healing index of 110.3day/cm(ranging from 34 to 290 days/cm).

SUMMARY POINTS  Ilizarov mini fixator is an external bone fixator designed to be set on the dorsal aspect of the hand and finger and thus can be applied to multiple fingers.  The fixation pin with a diameter of 1.2mm fits well to the small pediatric phalanges.  With this fixator, it is possible to carry out bone distraction and correction deformity at the same time.  It is useful for the improvement of hand skills, such as pinching, by elongating short fingers in children.  Due to insufficient hardness of the bone cortex, there is a possibility of fracture.

REFERENCES 1. Miyawaki T, Masuzawa G, Hirakawa M, Kurihara K, Bone-Lengthening For Symbrachydactyly Of The Hand With The Technique Of Callus Distraction. J Bone Joint Surg Am. 2002 Jun;84-A(6):p. 986-91. 2. Mann M, Hülsemann W, Winkler F, Habenicht R.,Distraction Osteogenesis is an Effective Method to Lengthen Digits inCongenital Malformations, Handchir Mikrochir Plast Chir. 2016 Feb;48(1):48-52. 3. Matsuno T, Ishida O, Sunagawa T, Ichikawa M, Ikuta Y, Ochi M. Bone Lengthening for Congenital Differences of the Hands and Digits in Children, J Hand Surg Am. 2004 Jul;29(4):712-9. 4. Shevtsov VI, Danilkin MY. Application of external fixation for management of hand syndactyly, Int Orthop. 2008 Aug;32(4):535-9.

FIGURES

Guest Society Poster 58: Venipuncture-Induced Peripheral Nerve Paralysis

AUTHORS Takao Omura, MD, PhD Tomokazu Sawada, MD, PhD Hiroaki Ogihara, MD Michito Miyagi, MD, PhD Yukihiro Matsuyama, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Venipuncture is the most frequent invasive and unavoidable medical procedure in clinical practice. However, the procedure may cause peripheral nerve injuries and in some cases leading to severe Complex Regional Pain Syndrome Type 2 (CRPS-II), or causalgia. The purpose of this study was to review cases of venipuncture-induced peripheral nerve paralysis referred to our department.

METHODS Twenty Patients who complained of pain and numbness after receiving venipuncture from 2010 to 2015 at our hospital were included in this study. All the patients were referred to the division of hand surgery by the attending physician. The patients consisted of 4 male, 16 females and the average age was 53.3 (20 to 80) years old. The affected nerves, clinical symptoms, the number of hospital visits and the costs of the treatment were reviewed.

RESULTS The incidence rate for the paralysis after venipuncture was 0.005% (20/ Out of 392,363). The affected nerves were superficial radial nerve in 6 cases, medial antebrachial cutaneous nerve in 5 cases, median nerve in 4 cases and 6 cases were unable to identify. Nine cases experience simultaneous radiating pain to the forearm at the time of puncture and six cases showed Tinel’s like sign at the site or distal to the puncture. Nine cases presented sensory disturbance (3 cases each for antebrachial cutaneous nerve, superficial radial nerve and 2 cases for median nerve) but none of the cases showed motor deficit. The average number of hospital visit was 1.7 times (1 to 5) and the average treatment cost was 6818 yen (700 to 68070). All the cases were treated conservatively and none of the cases developed CRPS like symptoms or ended up in litigation. At the final follow up, all the cases showed no neurological deficit.

SUMMARY POINTS  The incidence rate for Venipuncture-induced peripheral nerve paralysis was 0.005%.  The average visit to the hospital was 1.7 times.  All the cases showed rapid spontaneous recovery. Guest Society Poster 59: Transplanted Neurons in Peripheral Nerve Provide a Novel Treatment Strategy for Paralyzed Muscles

AUTHORS Shigeru Kurimoto, MD, PhD Tomonori Nakano, MD Hiroaki Shinkai Satoshi Nina Masahiro Tatebe, MD Hitoshi Hirata, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Basic Science LEVEL OF EVIDENCE: N/A

HYPOTHESIS Reinnervation prevents irreversible degeneration and leads to functional recovery after muscle denervation. Recent advances in stem cell research have opened up possibilities for reinnervating muscles without a neural connection to the central nervous system. Prior research demonstrates the successful survival of neurons transplanted into peripheral nerve. This transplantation strategy may provide the potential to artificially excite muscles when combined with functional electrical stimulation. In this study, we hypothesized that transplanted neurons prevent muscle degeneration and restore function following traumatic nerve injury.

METHODS Ventral spinal cord cells were obtained from Fischer 344 rat embryos. One week after sciatic nerve transection in adult Fischer 344 rats, medium containing dissociated embryonic spinal neurons was injected into the distal stump of the tibial and peroneal nerves. A critical size nerve defect was created by excising a 10 mm segment of the sciatic nerve and the nerves were ligated at both ends and the proximal nerve stump was sutured into hip muscles to prevent reinnervation. Electrophysiological, tissue and gait analyses were performed 12 weeks after transplantation.

RESULTS Transplanted motor neurons formed functional neuromuscular junctions. Following neuron transplantation, the proportion of the dispersed endplates was reduced. Immunohistochemical analysis of the transplant sites of functionally recovered rats demonstrated that motor neurons as well as astrocytes and oligodendrocytes survived in the peripheral nerves. This finding may indicate that glial cells in the central nervous system are important to optimize the intraneural environment for motor neurons that do not naturally exist in peripheral nerve. CMAPs were evoked after cell transplantation, even though no axonal connections to the central nervous system had been present for the preceding 12 weeks. In the rat sciatic nerve transection model, ankle motion was artificially restored during the gait cycle when combined with functional electrical stimulation. These data suggest that localized motor units and coordinated electrical signals utilizing physiological information restore the functional activity of partially paralyzed muscles following traumatic nerve injury.

SUMMARY POINTS  Transplanted spinal neurons and glial cells in the peripheral nerve formed functional motor units, even though no neural connection between central nervous system and muscle was present for the long-term.  Transplantation of motor neurons into the peripheral nerve combined with functional electrical stimulation provides the potential to artificially excite paralyzed muscle.

REFERENCES 1. Erb DE, Mora RJ, Bunge RP. Reinnervation of adult rat gastrocnemius muscle by embryonic motoneurons transplanted into the axotomized tibial nerve. Exp Neurol. 1993;124:372-6. 2. Kurimoto S, Kato S, Nakano T, Yamamoto M, Nishizuka T, Hirata H. Transplantation of embryonic motor neurons into peripheral nerve combined with functional electrical stimulation restores functional muscle activity in the rat sciatic nerve transection model. J Tissue Eng Regen Med, 2013.

This research was supported by a grant received from JSPS KAKENHI 23700664.

Guest Society Poster 60: A Vessel-Containing Nerve Conduit Implanted With Bone Marrow Stromal Cells And Thermally Decellularized Allogenic Nerve Matrix

AUTHORS Yukitoshi Kaizawa, MD, PhD Ryosuke Kakinoki, MD, PhD Ryosuke Ikeguchi, MD, PhD Soichi Ohta, MD, PhD Takashi Noguchi, MD, PhD Hiroki Oda, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Basic Science LEVEL OF EVIDENCE: N/A

HYPOTHESIS Nerve conduits are generally inferior to an autologous nerve graft (autograft) especially when repairing motor or mixed nerve injuries with long gaps. Our hypothesis is that the conduit containing vascularity, cells, and scaffold is comparable to an autograft.

METHODS A Lewis rat sciatic nerve model with a 20 mm gap was used. As vascularity, the sural arteriovenous bundle was elevated with its monitoring flap, turned proximally, and inserted into the silicon tube. As supportive cells, isogenic bone marrow stromal cells (BMSCs) in medium were injected into the lumen of the tube. As scaffold, decellularized allogenic nerve matrix (DANM) was implanted into the tube, which was prepared by freezing and thawing Dark Agouti rat sciatic nerves three times. The revascularization and the immunogenicity of the DANM were investigated using immunohistochemistry for RECA-1 and CD-8, respectively. The nerve regeneration across the 20 mm gap through the conduit (the conduit group, n=10) was compared to that via a reversed autograft (the autograft group, n=10) based on the functional, electrophysiological, and morphometric evaluations at 24 weeks. The data were statistically analyzed using the t-test.

RESULTS The immunohistochemistry revealed that RECA-1 positive cells were detected in the DANM around the sural vessels within a week and that the number of the CD8 positive cells in the DANM did not differ significantly from that in the autologous nerve segment. Gait analysis using CatWalk XT demonstrated significantly larger area of the foot print of the operated hind limb (P<0.05) and higher contact pressure of the operated hind limb (P=0.06) in the conduit group when compared to the autograft group. The electrophysiological studies revealed that the conduit group was superior to the autograft group, regarding the amplitude of the compound muscle action potential detected in the pedal adductor muscle (P=0.11) and the motor nerve conduction velocity (P=0.82). The morphometric evaluations, using transverse sections of the regenerated nerve 5 mm proximal to the distal suture, showed the smaller number (P=0.07) and the larger diameter (P=0.28) of the myelinated axons in the conduit group.

SUMMARY POINTS  The DANM in the conduit was revascularized in the early phase of nerve regeneration and caused no harmful rejection.  The nerve regeneration through the conduit was comparable to that via the autograft in a rat sciatic nerve model.  The nerve conduit containing vascularity, cells, and scaffold can be one of the promising strategies for the treatment of peripheral nerve injuries with gaps.

FIGURES

Guest Society Poster 61: Creation Of Ectopic Neural Ganglion Within Peripheral Nerve Graft

AUTHORS Tomonori Nakano, MD Shigeru Kurimoto, MD, PhD Kennichi Asano, MD Hiroki Shinnkai, MD Satoshi Niwa, MD Hitoshi Hirata, Md, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Basic Science LEVEL OF EVIDENCE: N/A

HYPOTHESIS Skeletal muscles including the diaphragm lose their functions by denervation following nerve injury or motoneuron disease, and never recover without connection with the central nervous system (CNS). Making ectopic neural ganglion as new dominant nerve for paralyzed muscle can be innovative strategy in regenerative medicine when combined with functional electrical stimulation. In this study, we show that embryonic spinal cord cells transplanted into a peripheral nerve graft construct neural ganglion similar to the CNS and reinnervate paralyzed muscles.

METHODS Fischer 344 rats were used. Bilateral sciatic nerves were transected, and a segment of peroneal nerve was excised and sutured to the tibialis anterior muscle as a free nerve graft. One week later, one million embryonic ventral spinal cord cells were transplanted into the free nerve graft. Twelve weeks later, electrophysiological and immunohistological analyses were performed.

RESULTS Frozen sections of tibialis anterior muscle and sutured free nerve were immunostained with pan- neuronal marker and alpha-bungarotoxin. Transplanted motoneurons survived and constructed nodule structure in the nerve graft, and then extended axons directionally into the muscle fiber. The axons induced new clustering of acetylcholine receptors and formed neuromuscular junctions with new and original acetylcholine receptors. Nodule structure was additionally analyzed in detail. In the nerve graft, Iba1 positive macrophages were activated by nerve damage, and there were GFAP positive astrocytes and O4 positive oligodendrocytes. Furthermore, synaptophysin was positive around nerve cell bodies reflecting synapse network was established between transplanted cells. The nodule structure was very similar to the spinal cord which is a part of the CNS (Figure 1). When the sutured free nerve was stimulated electrically, the ankle of rat was dorsiflexed with only 0.2 mA stimulation (Figure 2). Whereas the surgical control side never reacted. The weight of the tibialis anterior muscle was greater in the transplanted side than in the surgical control side (0.068 ± 0.012 % vs 0.053 ± 0.008 %, p<0.05), and muscle fiber cross-sectional area was also larger in the transplanted side (356 ± 345 µm2 vs 114 ± 132 µm2, p<0.01).

SUMMARY Transplanted ventral spinal cord cells formed nodular structure similar to the CNS in the free nerve graft. We can locate it anywhere as an ectopic neural ganglion and reinnervate skeletal muscle functionally. This technique may be new strategy of musculoskeletal regenerative medicine.

REFERENCES 1. Kurimoto S, Kato S, Nakano T, Yamamoto M, Nishizuka T, Hirata H. Transplantation of embryonic motor neurons into peripheral nerve combined with functional electrical stimulation restores functional muscle activity in the rat sciatic nerve transection model. J Tissue Eng Regen Med. 2013. 2. Erb DE, Mora RJ, Bunge RP. Reinnervation of adult rat gastrocnemius muscle by embryonic motoneurons transplanted into the axotomized tibial nerve. Exp Neurol. 1993;124:372-6. 3. Okano, H. Stem cell biology of the central nervous system. J Neuroscience Res. 2002;69:698–707.

FIGURES

This research was supported by a grant received from JSPS KAKENHI 15K21059.

Guest Society Poster 62: A Surgical Treatment Plan for Carpal Tunnel Syndrome Based on Electrophysiological Severity Scale

AUTHORS Takako Kanatani, MD Issei Nagura, MD Takeshi Kokubu, MD Yutaka Mifune, MD Atsuyuki Inui, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Our electrophysiological severity scale for carpal tunnel syndrome (CTS) could be a practical objective guide to the selection of surgical treatment.

METHODS One thousand and eighty hands with CTS (278 male and 802 female hands) were evaluated using the electrophysiological severity scale we developed: Stage 1: normal distal motor latency (DML) and normal sensory nerve conduction velocity (SCV),Stage 2:DML >4.5ms and normal SCV, Stage 3: DML >4.5ms and SCV 4.5ms and non-measurable SCV, Stage 5: non-measurable DML and non-measurable SCV.

We recommended carpal tunnel release for patients who presented with difficulty in pinching due to severe thenar atrophy and/or showed a poor response to a conservative treatment protocol after 2-8 weeks. However the final decision as to treatment (operative or conservative) was left to the patients’ discretion. We analyzed the ratio of operated cases in each stage using chi- squared analysis (p= 4.5ms, and SCV abnormal <40.0 m/s).

RESULTS The distribution of severity stages was: Stage 1; 50 hands (5%), Stage 2; 201 hands (19%), Stage 3; 236 hands (22%), Stage 4; 365 hands (34%) and Stage 5; 227 hands (21%), where Stage 4 was the most common. One hand was not classifiable (0.09%). Four hundred and forty-eight of 1080 hands (41%) selected surgery all told: Stage 1; 5 of 50 hands (10%), Stage 2; 27 of 201 hands (13%), Stage 3; 66 of 236 hands (28%), Stage 4:188 of 365 hands (52%) and Stage 5; 162 of 227 hands (71%), clearly patients with more severe Stage chose operation over conservative treatment for example patient with Stage 5 selected operative procedures significantly (p<0.0001).

SUMMARY POINTS  The decision to undergo surgical treatment was associated with the electrophysiological severity.  Our electrophysiological severity scale is useful as an objective tool in choosing treatment for CTS. Guest Society Poster 63: Time Course of Electrophysiological Parameters of the Carpal Tunnel Syndrome

AUTHORS Kaoru Tada, MD Daiki Yamamoto Tadahiro Nakajima Hiroyuki Tsuchiya, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 5

HYPOTHESIS The time course of the electrophysiological parameters of the carpal tunnel syndrome during the perioperative period is useful to confirm that the operation was performed appropriately.

METHODS The subjects were 30 patients (age: range, 49–84 years; mean, 67.6 years) treated with open carpal tunnel release (OCTR) performed by the same hand surgeon. OCTR was performed with two short incisions of the palm and wrist to confirm whether the transverse carpal ligament and forearm fascia were sectioned completely. All the patients showed clinical improvement of symptoms after operation, without any adverse events.

NCSs were performed preoperatively and at 1 month, 3 months, and 6 months after OCTR. The distal motor latency (DML) and compound muscle action potential (CMAP) of the abductor pollicis brevis (APB), second lumbrical (2L), first dorsal interossei (INT), and sensory nerve conduction (SCV) and sensory nerve action potential (SNAP) recorded at the index and middle fingers after distal stimulation were recorded. Furthermore, the difference in the second lumbrical and first dorsal interossei latencies (2L-INT) was measured. The time course of each parameter was analyzed with the linear mixed model and Bonferroni correction to adjust for multiple comparison (p < 0.05).

RESULTS APB DML, 2L DML, 2L-INT, index finger SCV, and middle finger SCV were significantly improved at all measurement dates from their preoperative values. Furthermore, 2L-INT, index finger SCV, and middle finger SCV significantly improved over time until 3 months after the operation. However, SCV could not be detected in many of the cases. None of the parameters significantly improved between 3 and 6 months after operation.

SUMMARY The results of this study suggest that DML and SCV were more useful parameters than CMAP and SNAP for observation of the recovery process after OCTR. Especially 2L-INT, which could be measured in many cases, might be an objective evaluation tool for recovery after OCTR.

Guest Society Poster 64: An Ultrasonographic Technique to Lower the Risk of Complications Associated with Endoscopic Carpal Tunnel Release

AUTHORS Katsunori Ohno, MD, PhD Shinji Hirofuji, MD, PhD Keitaro Fujino, MD Tsunehiko Ishidu, MD, PhD Sadamasa Kira, MD Masashi Neo, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Ultrasonography (US)-assisted endoscopic carpal tunnel release would be beneficial in preventing complications such as nerve and arterial injury and incomplete release. To this end, we prospectively evaluated clinical outcomes, and determined in intra- and inter-observer reliability of US-based assessment of flexor retinaculum release.

METHODS US-assisted endoscopic carpal tunnel release was performed on 22 consecutive hands in 20 patients, using the Okutsu one-portal technique. We observed the carpal tunnel region on transverse and longitudinal views. When the outer tube was inserted, we evaluated whether the positional relationships of the median nerve, outer tube, ulnar artery, and superficial palmar artery were appropriate. Before and after releasing the flexor retinaculum, we lifted the outer tube upward to evaluate the degree of motion of the tube. We named this maneuver “Lift-up test”. Numbness, nocturnal pain, grip strength, key pinch strength, Semmes-Weinstein test, nerve conduction study results, and patient-reported questionnaires were evaluated before surgery and 6 months after surgery. All US images were recorded as motion clips. In each imaging region, we evaluated intra- and interobserver reliability of diagnosis for the Lift-up test. Physical assessments were analyzed using a paired t-test. To evaluate intra- and inter-observer reliability, the Kappa coefficient was calculated with a 95% confidence interval. The concordance rate for diagnosis of the Lift-up test between the operator and the observers (observer 1, 2) was evaluated using the chi-squared test. A p-value <0.05 was considered to be statistically significant.

RESULTS There were no surgical complications, and all physical assessments except grip strength had improved 6 months after surgery. When we performed the Lift-up test before releasing the flexor retinaculum, the tube could be lifted very little. However, after complete release, the tube could be lifted up easily in the transverse view. The longitudinal view also showed that the distal end of the tube could be lifted up to be superior to the superficial palmar artery after release (Figure 1). There was substantial to almost perfect agreement in intra- and inter-observer reliability for each view (Table 1).

SUMMARY POINTS  US-assisted endoscopic carpal tunnel release is useful to prevent intra-operative complications.  The Lift-up test was an effective technique to avoid incomplete release of the flexor retinaculum.

REFERENCES 1. Okutsu I, Ninomiya S, Takatori Y, Ugawa Y. Endoscopic management of carpal tunnel syndrome. Arthroscopy. 1989;5:11–18. 2. Murphy RX Jr, Jennings JF, Wukich DK. Major neurovascular complications of endoscopic carpal tunnel release. J Hand Surg Am. 1994;19:114–118. 3. Rotman MB, Donovan JP. Practical anatomy of the carpal tunnel. Hand Clin. 2003;18:219–230. 4. Rotman MB, Manske PR. Anatomic relationships of an endoscopic carpal tunnel device to surrounding structures. J Hand Surg Am. 1993;18:442–450. 5. Fowler JR, Hirsch D, Kruse K. The reliability of ultrasound measurement of the median nerve at the carpal tunnel inlet. J Hand Surg Am. 2015;40:1992–1995.

FIGURES

Guest Society Poster 65: Pathology of the Epineurium of Spontaneous Median Nerve Palsy with Hourglass-Like Constriction: 3 Cases

AUTHORS Akira Ikumi, MD Yuki Hara, MD, PhD Yasumasa Nishiura, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Spontaneous median nerve palsy is an unexplained disorder that begins with acute pain and progresses to median nerve palsy within a few weeks. There is still no established standard therapy.

The development of an hourglass-like constriction in the median nerve has been reported to occur in spontaneous palsy, but its origin remains unknown. The purpose of this study was to evaluate the pathologic features of the excised epineuria of 3 patients who had spontaneous palsy with an hourglass-like constriction.

METHODS The epineurium was excised from 3 female patients (aged 44, 50, 54 years) diagnosed as having spontaneous palsy. All patients began with prodromal symptoms (pain around the elbow) that progressed to paralysis at the median nerve area (flexor pollicis longus, flexor digitorum profundus/superficialis (index finger), and flexor carpi radialis). The palsy did not recover after conservative treatment, and we therefore performed interfascicular neurolysis (duration from onset to surgery, 5, 6, 9 months).

Intraoperatively, an hourglass-like constriction was identified in each case (Fig. 1), and the epineurium surrounding the constriction was stripped off and excised. Two of the patients obtained good recovery of motor function after surgery, but the third patient (neurolysis at 9 month) obtained none.

We divided the epineurium into 2 layers: just above the constriction (deep layer) and around it (superficial layer). The sections were stained with hematoxylin-eosin and Masson’s Trichrome, and by immunohistochemistry in preparation for light microscopy. We checked for the presence of inflammatory cells, outgrowing collagen fibers, and focally gathered or infiltrating lymphocytes.

RESULTS Histopathologic examination of the excised epineuria yielded similar findings. In each case, outgrowing collagen fibers were observed in the deep layer. Focally gathered lymphocytes were present in the perivascular area of the superficial layer. The focally gathered lymphocytes consisted of CD4- and CD20-positive (B) cells, rather than of CD3- and CD8-positive (T) cells (Fig. 2), and few CD68-positive cells (macrophages) were present. Inflammatory infiltrates within the small vessels were observed, but fibrinoid degeneration of the vascular walls was not.

SUMMARY In the excised epineuria of spontaneous palsy, outgrowing collagen fibers and focally gathered lymphocytes were observed in the perivascular area. Since inflammatory infiltration was evident in all of the excised epineuria, inflammation may be involved in the onset of spontaneous palsy. The pathologic findings of spontaneous palsy are similar to those of neuralgic amyotrophy.

REFERENCES 1. Nagano A : Spontaneous anterior interosseous nerve palsy. JBJS Br 85 :313-8, 2003. 2. Chi Y, Harness NG : Anterior interosseous nerve syndrome. JHS Am 35 :2078-80, 2010. 3. Nagano A et al : Spontaneous anterior interosseous nerve palsy with hourglass-like fascicular constriction within the main trunk of the median nerve. JHS Am 21 :266-70, 1996. 4. Ochi K, Kato H : Pathophysiology and treatment of spontaneous anterior interosseous nerve palsy and spontaneous posterior interosseous nerve palsy. Brain and Nerve 66 : 1441-52, 2014. 5. Yong-wei P et al : Hourglass-like constrictions of peripheral nerve in the upper extremity: A clinical review and pathological study. Neurosurgery 75 :10-22, 2014. 6. Yong-wei P et al : Typical brachial neuritis (Parsonage-Turner syndrome) with hourglass-like constrictions in the affected nerves. JHS Am, 2011. 7. Nens VA : Clinical and pathophysiological concepts of neuralgic amyotrophy. Nat. Rev. Neurol 7 :315-22, 2011.

FIGURES

Guest Society Poster 66: Comparative Study of Current Perception Threshold between Nociceptive and Neuropathic Pain Patients

AUTHORS Masatoshi Amako, MD Hiroshi Arino, MD, PhD Yoshifumi Tsuda, MD, PhD Yasufumi Hirahara, MD Dr. Koichi Nemoto, MD, PhD Kazuhiro Chiba, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Current perception threshold (CPT) was proposed as a quantitative method for assessment of peripheral sensory nerve function to selectively evaluate the nerve function in Aß, Ad and C fibers. Nociceptive (NC) pain may be transmitted mainly via C fiber, and neuropathic (NP) pain may be conducted not only via C fiber, but via Ad fiber, however, characteristics of CPT for both pain patterns have not been elucidated. We hypothesized that CPT ratio in Aß, Ad and C fibers was different between NC and NP pain. The purpose of this study was to clarify the characteristics of CPT in patients with NC and NP pain.

METHODS Twenty-six patients with painful disorders of the shoulder (shoulder group; including 12 rotator cuff tear, 8 labral tear, and 6 SLAP lesions) and 36 patients with carpal tunnel syndrome (CTS group) underwent bilateral measurements of CPTs using Neurometer® (Neurotron, USA). The simulation site was anterior aspect of the shoulder joint in the shoulder group, and the distal phalanx of the index finger in the CPT group. We calculated CPT ratio (CPT at injured side/ CPT at contralateral side) in three conditions of 2000, 250, and 5Hz stimulation, which could selectively stimulate Aß, Ad and C fibers. Mann-Whitney U test and Kruskal-Wallis test were performed to examine the difference of CPT ratios between the two groups using JMP®11 (SAS Institute Inc., Cary, NC, USA).

RESULTS In the shoulder group, the 5Hz CPT ratio was the highest (1.9 ± 0.3) compared to those at 2000Hz and 250Hz (1.1 ± 0.4, 1.3 ± 0.7, respectively). In the CTS group, the CPT ratios were increased at all conditions (2000Hz: 2.4 ± 0.9, 250Hz: 3.2 ± 2.1, 5Hz: 1.7 ± 0.9), among which the 250Hz CPT ratio was the highest. The CPT ratios in the CTS group were significantly higher at both 2000 and 250 Hz than those in the shoulder group (p<0.0001), however, there was no significant difference at 5Hz.

SUMMARY POINTS  Only 5Hz CPT ratio was increased in NC pain, on the other hand NP pain induced high CPT ratios at all 3 conditions, especially at 250Hz.  High 2000Hz CPT ratio in the CTS group may indicate that Aß fibers that transmit tactile sensation were also affected in neuropathic pain and could cause paresthesia.

REFERENCES 1. Katims JJ, Patil AS, Rendell M, Rouvelas P, Sadler B, Weseley SA, Bleecker ML. Current perception threshold screening for carpal tunnel syndrome. Arch Environ Health. 1991;46(4):207-12.

FIGURES

Guest Society Poster 67: Diffusion Tensor Tractography of the Median Nerve for the Diagnosis of Carpal Tunnel Syndrome

AUTHORS Eiko Yamabe, MD, PhD Hiroshi Yoshioka, MD, PhD Kazuaki Mito, MD Toshiyasu Nakamura, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 2

HYPOTHESIS Recently, the median nerve at the carpal tunnel has been visualized with diffusion MRI with a technique known as diffusion tensor tractography (DTT) (1, 2). We hypothesized that we could demonstrate the clinical feasibility of using DTT onthe median nerve for the diagnosis of carpal tunnel syndrome (CTS) by investigating the changes in diffusion values such as fractional anisotropy (FA) and apparent diffusion coefficient (ADC) quantitatively, and visualizing the median nerve on fiber tracking images qualitatively.

METHODS We examined 4 wrists from 4 CTS patients (group A; mean age 52.3 y/o) and 8 wrists from 8 healthy volunteers (group B; mean age 42.4 y/o), respectively. All DTTs were obtained using an 8-channel wrist coil at 3T. Sequence parameters are as follows; P and S1: TR/TE=4600- 5258/79ms, flip angle=90, FOV=90mm, b-value=800s/mm2, pixel size=1.07/1.02mm, slice thickness=4mm, S2: TR/TE=4600-4908/69-80ms and pixel size=1.18/1.12, and S3: TE=68ms and FOV=110mm. As a qualitative evaluation, we created fiber tracking of the median nerve at first. “Zero point” (Z) was set at the level of the radial styloid tip, and this pointwas considered to be the proximal end of the carpal tunnel. Mean FA and ADC at the 12, 8, 4, 0mm proximal (-12, -8, -4, 0) and 4, 8, 12, 16, 20, 24, 28, 32mm distal (+4, +8, +12, +16, +20, +24, +28, +32) to the Z were measured by placing a region of interest in expected axial DTI. Comparisons between group A and B were performed by Scheffe post hoc test.

RESULTS On fiber tracking images, the median nerve (including its motor branch) was well visualized and morphological changes were appreciated around the carpal tunnel. FA and location of the median nerve of group B demonstrated a negative linear correlation from the proximal (0.73 at -12 mm) to the distal aspect of the carpal tunnel(0.45 at +24 mm), while ADC showed a peak at the midst of carpal tunnel (1.087 at -12 mm, 1.227 at =8 mm, and 0.873 at +28 mm). Though we observed a similar tendency of FA and ADC in group A, FA was significantly lower and ADC was significantly higher especially at within carpal tunnel (0 to +24 mm) (P<0.05) compared with those of group B.

SUMMARY FA/ADC of the median nerve had different values in health subjects when compared to those patients with the diagnosis of carpal tunnel syndrome, especially when the nerve was examined within the carpal tunnel. This result suggested that DTT of the median nerve could be a useful tool for the diagnosis of carpal tunnel syndrome.

REFERENCES 1 Kabakci N, Gurses B, Firat Z, et al. Diffusion tensor imaing and tractography of median nerve: normative diffusion values. Am J Roentgenol 2007;189(4):923-927. 2 Khalil C, Hancart C, Le Thuc V, et al. Diffusion tensor imaging and tractography of the median nerve in carpal tunnel syndrome: preliminary results. Eur Radiol 2008;18(10):2283-2291.

Guest Society Poster 68: Is Ultrasound Examination Useful to Assess the Treatment Effect of Carpal Tunnel Release?

AUTHORS Tsuyoshi Tajika, MD, PhD Noboru Oya, MD Atsushi Yamamoto, MD, PhD Kenji Takagishi, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 2

HYPOTHESIS We hypothesized that ultrasound examination was useful to assess the treatment effect of carpal tunnel release in patients with carpal tunnel syndrome (CTS).

METHODS A prospective study was conducted on 34 wrists of 28 CTS patients (mean age: 57.9 years, range 30-85 years; 10 men and 18 women). We evaluated the treatment effect using Carpal Tunnel Syndrome Instrument and Quick Disability of Arm, Shoulder, and Hand questionnaire of the Japanese Society for Surgery of the Hand version (CTSI-JSSH, Quick DASH-JSSH), nerve conduction, ultrasound (US) of preoperatively and at 6 months and one year postoperatively (6 months follow up: 10 men and 18 women, one year follow up: 4men and 9 women). We assessed the morphological change of cross sectional area (CSA) of the median nerve measured at the level of proximal inlet of the carpal tunnel and those measured more proximally at the level of the distal radioulnar joint before and after surgery of CTS. Paired t test and repeated-measures analysis of variance (ANOVA) of ranks were to identify changes following variables over time. Spearman’s correlation coefficient by rank test was used for analysis of the relation between the size of CSA and CTSI-JSSH and Quick DASH-JSSH score and NCS findings. P <0.05 was considered statistically significant.

RESULTS CSA at the level of proximal inlet of the carpal tunnel at 6 months and one year postoperatively decreased significantly by comparing with those at preoperatively (P<0.001). Statistical significant correlation was found between the amount of change of symptom status scale of Quick DASH JSSH (preoperative score minus postoperative 6 months score) and the amount of change of CSA at the level of the distal radioulnar joint before and after operation (6months follow-up). (r=0.49, p=0.02)

SUMMARY POINTS  CSA at the proximal inlet carpal tunnel and CSA at the distal radioulnar joint at 6 months and one year postoperatively decreased significantly by comparing with those at preoperatively.  Statistical significant correlation was found between the amount of change of symptom status scale of Quick DASH JSSH and the amount of change of CSA at the distal radioulnar joint before and after operation (6months follow-up)  Evaluation of sonographic imaging might be helpful for assessing the subjective symptom severity after operation (6 months follow-up) in CTS patients.

REFERENCES 1 Nakamichi KI, Tachibana S. Enlarged median nerve in idiopathic carpal tunnel syndrome. Muscle Nerve. 2000, 23: 1713–1718. 2 Wiesler ER, Chloros GD, Cartwright MS, Smith BP, Rushing J, Walker FO. The use of diagnostic ultrasound in carpal tunnel syndrome. J Hand Surg Am. 2006, 31: 726–732. 3 Lundborg G, Myers R, Powell H. Nerve compression injury and increased endoneurial fluid pressure: a “miniature compartment syndrome”. J Neurol Neurosurg Psychiatry. 1983, 46: 1119–1124. 4 Yayama T, Kobayashi S, Nakanishi Y, Uchida K, Kokubo Y, Miyazaki T, Takeno K, Awara K, Mwaka ES, Iwamoto Y, Baba H.Effects of graded mechanical compression of rabbit sciatic nerve on nerve blood flow and electrophysiological properties. J Clin Neurosci. 2010 Apr;17(4):501-5. 5 Tajika T, Kobayashi T, Yamamoto A, Kaneko T, Takagishi K.Diagnostic utility of sonography and correlation between sonographic and clinical findings in patients with carpal tunnel syndrome. J Ultrasound Med. 2013 Nov;32(11):1987-93. 6 Paude L, Pazzaglia C, Caliandro P Granata G, Foschini M, Briani C, Martinoli C. Carpal tunnel syndrome: ultrasound, neurophysiology, clinical and patient-oriented assessment. Clin Neurophysiol 2008,119: 2064–2069. 7 Karadag YS, Karadag Ö, Çi?ekli E. Oztürk S, Kiraz S, Ozbakir S, Filippucci E, Grassi W. Severity of carpal tunnel syndrome assessed with high frequency ultrasonography. Rheumatol Int. 2010, 30: 761–765. 8 Kim JY, Yoon JS, Kim SJ, Won SJ, Jeong JS.Carpal tunnel syndrome: Clinical, electrophysiological, and ultrasonographic ratio after surgery. Muscle Nerve. 2012 Feb;45(2):183-8 9 Smidt MH, Visser LH.Carpal tunnel syndrome: clinical and sonographic follow-up after surgery. Muscle Nerve. 2008 Aug;38(2):987-91. 10 Abicalaf CA, de Barros N, Sernik RA, Pimentel BF, Braga-Baiak A, Braga L, Houvet P, Brasseur JL, Roger B, Cerri GG. Ultrasound evaluation of patients with carpal tunnel syndrome before and after endoscopic release of the transverse carpal ligament. Clin Radiol. 2007 Sep;62(9):891-4

Guest Society Poster 69: Associations Between Ulnar Nerve Strain and Accompanying Conditions in Patients With Cubital Tunnel Syndrome

AUTHORS Kensuke Ochi, MD, PhD Yukio Horiuchi, MD Koichi Horiuchi, MD Yasushi Morisawa, MD Takuji Iwamoto, MD, PhD Kazuki Sato, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis;Anatomy;Basic Science LEVEL OF EVIDENCE: Level 3

HYPOTHESIS We have shown that pathophysiology of cubital tunnel syndrome (CubTS) could not be explained simply by pressure inside the cubital tunnel [1, 2]. The purpose of this study is to investigate whether ulnar nerve strain is associated with accompanying condition in patients with CubTS.

METHODS Eighteen patients with CubTS were divided into four groups according to their accompanying conditions based on their surgical findings; group I: compression at distal upper arm level (compression by medial head of the triceps/ Struthers’ arcade); group II: compression/adhesion at the level of cubital tunnel; group III: idiopathic; group IV: relaxation (dislocation of the ulnar nerve, cubitus varus). The ulnar nerve strain at the elbow was intraoperatively measured at elbow maximum extension/flexion, according to previous report [3, 4]. In brief, the ulnar nerve strain was measured directly as elongation of the epineurium. Two 5-0-nylon sutures were placed on the epineurium of the ulnar nerve. The tourniquet was deflated, a reference ruler was placed next to the suture markers on the ulnar nerve, and photographs of the 2 suture markers and reference ruler were taken. The “distance between the 2 suture markers” (L) and “10 mm distance on the reference ruler” (l) at maximum elbow extension were measured using Image-J. The “distance between the 2 suture markers” (L’) and “10 mm distance on the reference ruler” (l’) at maximum elbow flexion were also measured using Image-J. Strain was calculated and converted to a percentage by using the following equation: strain = ((L’/l’)/(L/l) - 1) x 100. Each measurement was triplicated using 3 independent photographs. Statistic analysis was performed by Jonckheere-Terpstra test at a confidence level of 95% (p < 0.05).

RESULTS Mean age, mean ulnar nerve strain, mean results of 5-second elbow flexion test and 5-second shoulder internal rotation elbow flexion test [4, 5] were (41 y/o, 34.0 ± 12.0%, 25%, 50%) in group I, (48 y/o, 18.0 ± 9.1%, 50%, 67%) in group II, (55 y/o, 16.0 ± 3.7%, 75%, 100%) in group III, and (57 y/o, 7.3 ± 5.1%, 0%, 100%) in group IV, respectively. The Jonckheere- Terpstra test showed that there were significant reductions in the ulnar nerve strain among these four groups.

SUMMARY POINTS  This study indicated that ulnar nerve strain had significant association between accompanying condition in patients with CubTS.  The pathophysiology of CubTS may be explained at least in part by the presence of ulnar nerve strain.

REFERENCES 1 Ochi K, Horiuchi Y, Nakamichi N, et al. Association between the elbow flexion test and extraneural pressure inside the cubital tunnel. J Hand Surg Am. 2011; 36: 216-221. 2 Ochi K, Horiuchi Y. A less invasive, intraoperative method for measuring pressure in the cubital tunnel. J Hand Surg Eur Vol. 2010; 35: 767-768. 3 Ochi K, Horiuchi Y, Nakamura T, et al. Ulnar nerve strain at the elbow in patients with cubital tunnel syndrome: effect of simple decompression. J Hand Surg Eur Vol. 2013; 38: 474-480. 4 Ochi K, Horiuchi Y, Horiuchi K, et al. Shoulder position increases ulnar nerve strain at the elbow of patients with cubital tunnel syndrome. J Shoulder Elbow Surg. 2015; 24: 1380-1385. 5 Ochi K, Horiuchi Y, Tanabe A, et al. Shoulder internal rotation elbow flexion test for diagnosing cubital tunnel syndrome. J Shoulder Elbow Surg. 2012; 21: 777-781.

FIGURES

Guest Society Poster 70: Clinical Characteristics of Tumorous Lesions of Digital Nerves

AUTHORS Naoki Osamura, MD, PhD Kazuo Ikeda, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Evaluation/Diagnosis;Treatment LEVEL OF EVIDENCE: Level 4

HYPOTHESIS We report the clinical characteristics of tumorous lesions of digital nerves.

METHODS We surgically treated seven cases of tumorous lesions of digital nerves. The mean age at surgery was 44 years and the mean postoperative follow-up period was 68.4 months. The tumors were classified into two groups, designated the peripheral neural sheath tumor (PNST) group and the non-peripheral neural sheath tumor (non-PNST) group. The PNST group included three schwannomas and one neurofibroma. The non-PNST group included one nodular fasciitis, one myofibroma, and one hematoma. We investigated the following data in the two groups: lesion location; time between onset of symptoms and surgery; imaging findings on MRI; preoperative and postoperative symptoms; surgical findings; and history of recurrence.

RESULTS In the PNST group, three tumors were located in the middle finger and one in the ring finger. In the non-PNST group, all tumors were located in the palm. The mean time between onset of symptoms and surgery was 46.5 months in the PNST group and 1.8 months in the non-PNST group. Target signs on MRI T2-weighted images were seen in two cases (50%) in the PNST group and no cases (0%) in the non-PNST group. Local tenderness was detected in all cases (100%) in the PNST group and one case (33%) in the non-PNST group. Tinel’s sign was noted in three cases (75%) in the PNST group and all cases (100%) in the non-PNST group. Paresthesia was noted in no cases (0%) in the PNST group and all cases (100%) in the non- PNST group. All tumors in the PNST group were enucleated and the hematoma was removed without nerve damage. However, complete removal was not possible without loss of neurological function because of severe adhesion to the digital nerve for nodular fasciitis and myofibroma. Nodular fasciitis was resected with the entrapped digital nerve and an autologous nerve graft was performed. Postoperative paresthesia was noted in two cases (66%) in the non- PNST group. Local recurrence was not seen in any cases during the follow-up period.

SUMMARY POINTS  Tumorous lesions except for peripheral neural sheath tumors should be considered for patients with preoperative paresthesia and rapid growth of the mass.  Patients with non-peripheral neural sheath tumors should be informed of the possibility nerve grafting because complete removal may be impossible without loss of neurological function owing to severe adhesion to the digital nerve.

Guest Society Poster 71: Second Lumbrical-Interossei Nerve Test Predicts Clinical Severity and Surgical Outcome of Carpal Tunnel Syndrome

AUTHORS Tomoo Inukai, MD, PhD Kazuichiro Hori, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Prognosis/Outcomes LEVEL OF EVIDENCE: Level 3

HYPOTHESIS The second lumbrical-interossei nerve test (2L-IN, also known as the second lumbrical- interosseous distal motor nerve latency test, or 2LI-DML test) is a motor conduction technique initially described as being fairly valuable in the diagnosis of CTS. Several studies reported the high diagnostic sensitivity of 2L-IN in CTS, leading the American Association of Electrodiagnostic Medicine to recommend the 2L-IN test for the diagnosis of CTS when the standard median motor response at abductor pollicis brevis is difficult to record. The purpose of this study was to examine the utility of the 2L-IN test in the diagnosis of CTS.

METHODS We examined 65 patients with suspected unilateral CTS using the 2L-IN test, in addition to the standard electrophysiological test. The operative cases were divided into three classes of severity based on Padua’s neurophysiological classification. With the 2L-IN test, the extreme CTS group could be further subdivided into extreme CTS-A (both APB-CMAP and 2L-CMAP not recordable) and extreme CTS-B (2L-CMAP recordable, APB-CMAP not recordable). The age, duration of symptoms and BMI of the four groups, stratified according to preoperative electrodiagnostic severity, were compared using one-way analysis of variance (ANOVA). The postoperative clinical results collected at 6 months after surgery were analyzed and classified into four categories (excellent, good, fair and poor) according to relief of symptoms.

RESULTS The extreme CTS-A group included eight hands (12%). The extreme CTS-B group included nine hands (14%). The severe CTS group included 14 hands (21.5%). The moderate CTS group included 34 hands (52%) (Table1). The clinical results for the extreme CTS-A were fair in five cases and poor in three cases, while for extreme CTS-B, six patients had good results and three with fair results. The clinical results for severe CTS were excellent in three cases, good in eight, and fair in three cases, while for moderate CTS they were excellent in 24 hands and good in 10 hands, with no fair or poor results (Table2).

SUMMARY POINTS

 Patients with extreme CTS and severe CTS were older, had chronic symptoms, and poorer outcome compared with the moderate CTS patients.  Patients of the moderate CTS group were almost satisfied with the results of surgery.  The electrodiagnostic severity correlated with the clinical outcome.  Severe strangulation of the thenar muscle branch was identified in patients of the extreme CTS-B group, requiring decompression of the thenar muscle branch rather than conventional transverse ligament detachment.

REFERENCES 1 Padua L, LoMonaco M, Gregori B, et al. Neurophysiological classification and sensitivity in 500 carpal tunnel syndrome hands, Acta Neurol Scand 1997;96:211-7 2 Kelly CP, Pulisetti D, Jamieson AM. Early experience with endoscopic carpal tunnel release, J Hand Surg [Br] 1994;19B:18-21 3 Nobuta S, Sato K, Komatsu T, et al. Clinical results in severe carpal tunnel syndrome and motor nerve conduction studies. J Orthop Sci 2005;10:22-6 4 Strickland JW, Gozani S. Accuracy of In-Office nerve conduction studies for median neuropathy: A meta-analysis. J Hand Surg 2011;36A:52-60 5 Preston DC, Logigian EL. Lumbrical and interossei recording in carpal tunnel syndrome. Muscle Nerve 1992;15:1253-7 6 Ueno H, Kaneko K, Taguchi T, et al. Endoscopic carpal tunnel release and nerve conduction studies, Int Orthop 2001;24:361-3 7 Kaul MP, Pagel KJ. Value of the lumbrical-interosseous technique in carpal tunnel syndrome. Am J Phys Med Rehabil 2002;81:691-5 8 Argyriou AA, Karanasions P, Markidou A, et al. The significance of second lumbrical interosseous latency comparison in the diagnosis of carpal tunnel syndrome. Acta Neurol Scand 2009;120:198-203 9 Dudley Porras AF, Rojo Alaminos P, Vinuales JI, et al. Value of electrodiagnostic tests in carpal tunnel syndrome. J Hand Surg Br 2000;25:361-5 10 Loschner WN, Grumbach MA, Trinka E, et al. Comparison of second lumbrical and interosseous latencies with standard measures of median nerve function across the carpal tunnel: a prospective study of 450 hands. J Neurol 2000;247:530-4

FIGURES

Guest Society Poster 72: Clinical Outcome of Idiopathic Carpal Tunnel Syndrome With Advanced Thenar Atrophy - A New Treatment Concept for Recurrent Branch of Median Nerve

AUTHORS Jun Ikeda, MD Kazunari Tomita, MD, PhD Keikichi Kawasaki, MD, PhD Masanori Nakamura, MD, PhD Katsunori Inagaki, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 3

HYPOTHESIS It is still a clinical challenge to improve postoperative clinical outcome for idiopathic carpal tunnel syndrome (CTS) which has severe thenar atrophy. In these cases, we have been tried a new treatment concept for recurrent branch decompression of median nerve (MN). We applied a neurolysis to the recurrent branch of MN (RBMN) entirely, especially at the entrance of abductor polis brevis (APB) by using microsurgical technique after the usual procedure of open carpal tunnel release. The purpose of this study is to retrospectively review the clinical outcome of this neurolysis procedure.

METHODS Twenty-two hands were evaluated that could be followed at least a year after surgery. All of them were female and mean age was 70 years old. Postoperative recovery of the strength of APB muscle was evaluated by using manual muscle test.

RESULTS Postoperative recovery of APB strength was noted in 19 hands (86%), but recovery of APB muscle strength could not be obtained at all in 3 hands(14%). Interestingly, according to the findings during surgery, MN was entrapped not only at the trunk of MN in carpal tunnel but also at the entrance of APB severely in 14 hands (64%). Moreover, none of the findings such as constriction or hyperemia were noted in carpal tunnel, but RBMN was entrapped severely at the entrance of APB in 3 hands (14%). Finally, the APB strength recovered to average of almost [3] after 1 year of surgery, and it recovered to [5] in 5 cases after operation.

SUMMARY These results suggest that advanced motor nerve paralysis of CTS may be caused by double lesion. Therefore, a neurolysis to the RBMN for the main purpose of decompression at the APB entrance will be needed in addition to usual carpal tunnel release in some cases. We strongly recommend this procedure, especially for the patient who has severe atrophy of APB without sensory disturbance. It is very important to treat CTS with this possibility in mind.

REFERENCES 1 Amadio PC, et al. Anatomic variations of the median nerve within the carpal tunnel syndrome. Clin Anat,, 1: 23-31, 1988. 2 Bennet JB, et al. Compression syndrome of the recurrent mortor branch of the median nerve. J Hand Surg, 7: 407-409, 1982.

Guest Society Poster 73: Finger Flexor Tenosynovectomy for Carpal Tunnel Syndrome

AUTHORS Keizo Fukumoto, MD Naoki Kato, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Edema and hypertrophy of the synovial membrane of the flexor tendon are associated with the carpal tunnel syndrome. Carpal tunnel release is the main surgical intervention but is associated with postoperative pillar pain. Synovectomy of the flexor tendon aims to treat carpal tunnel syndrome without resecting the transverse carpal ligament. We offer flexor synovectomy to patients with mild symptoms responsive to steroid injection. Herein, we report outcomes of flexor synovectomy in our hospital.

METHODS Subjects were 22 female patients (25 hands) with carpal tunnel syndrome, who had repeated recurrence despite temporary alleviation of numbness by steroid injection. The mean age was 56.9 years, and 13 cases was complicated by trigger finger. The mean time between the initial examination and surgery was 24 months, and the mean number of steroid injections was 6.2. Motor conduction velocity (MCV) terminal latency was normal in 15 hands and delayed in 9. An approximately 3-cm incision was made between the palmaris longus muscle on the palmar side of the wrist and the tendon of the flexor carpi ulnaris muscle, and tenosynovectomy of the flexor digitorum superficialis and the flexor digitorum profundus was performed until the point exceeding the peripheral edge of the transverse carpal ligament, while flexing and extending the wrist and fingers.

RESULTS The mean duration of postoperative follow-up was 16.9 months (range, 6–36 months), and numbness was completely relieved at the time of final examination in 23 hands. Numbness, albeit temporary, reoccurred in 5 hands, 3 of which responded to steroid injection. Numbness was not alleviated in 1 patient with severe thenar muscle atrophy, and thus, carpal tunnel release was performed additionally. Stiffness remained in 2 hands at the time of final examination. The mean age at the time of surgery was 54.3 years in the group without recurrence, while it was 63.4 years in the group with recurrence (including temporary recurrence): the difference between two groups was significant (p = 0.03). The number of pre-operative steroid injections, the period between the initial examination and surgery, complication of trigger finger and MCV terminal latency were not significantly different between the two groups.

SUMMARY Outcomes of flexor tenosynovectomy were favorable, and postoperative pillar pain was absent in all cases. Flexor tenosynovectomy can be performed for primarily mild carpal tunnel syndrome without thenar muscle atrophy and is considered to fundamentally treat the pathology of carpal tunnel syndrome.

REFERENCES 1 Ketchum LD. A comparison of flexor tenosynovectomy, open carpal tunnel release, and open carpal tunnel release with flexor tenosynovectomy in the treatment of carpal tunnel syndrome. Plast Reconstr Surg. 2004;113(7):2020-2029. 2 Tsuruta T, Asami A, Sonohata M. Tenosynovectomy of finger flexor tendons for idiopahtic carpal tunnel syndrome. J Jpn Soc Surg Hand. 2002;19(4):466-468. 3 Ettema AM, Zhao C, Amadio PC, O'Byrne MM, An KN. Gliding characteristics of flexor tendon and tenosynovium in carpal tunnel syndrome: a pilot study. Cinical Anatomy. 2007;20:292-299.

Guest Society Poster 74: Scope Assisted Anterior Transposition of the Ulnar Nerve for the Cubital Tunnel Syndrome

AUTHORS Keiichi Murata, MD, PhD Hiroshi Yajima, MD. PhD Shohei Omokawa, MD, PhD Kenji Kawamura, MD, PhD Dr. Susumu Tamai, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Treatment;Surgical Technique LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Endoscopic assisted ulnar nerve release and anterior transposition (EAUNRAT) has equivalent surgical efficacy when compared with open technique for cubital tunnel syndrome (CuTS) accompanied by cubitus valgus or symptomatic repetitive anterior dislocation of the nerve.

METHODS A 2.5cm longitudinal incision is made between the medial epicondyle and olecranon. Blunt dissection is performed to the level of the cubital retinaculum, An 8cm long rhinoscope is introduced to create an endoscopic working space between the fascia and the subcutaneous tissue for approximately 8cm distally and proximally. Under endoscopic vision, the cubital retinaculum over the ulnar nerve is incised with Metzenbaum scissors to expose the ulnar nerve, the nerve is released with fine Overholt forceps. After completion of nerve release, the transposition is performed to an anterior subcutaneous space. The medial intermuscular septum is incised and removed. Since 2012, 14 elbows of 13 patients with an age of 44 years (range 13 to 79) underwent this procedure with at least 1-year follow up. There were 7 males and 7 females. Preoperative symptom’s severity (McGowan classification) was Grade 1 in 4 cases, Grade 2 in 6, Grade 3 in 4. We evaluated surgery time, Disabilities of the Arm, Shoulder and Hand (DASH) score, pain (VAS), grip strength, Messina index as an objective postoperative outcome and complications.

RESULTS Postoperative follow up period was 14 months (average). Surgery time was ranged from 42 to 88 minutes with an average of 60 minutes. DASH score, pain (VAS), grip strength was significantly improved after surgery. Messina index at the final follow-up was excellent in 6 cases, good in 5, fair 3. Two patients had complications of irritation of the medial cutaneous antebrachial nerve (MCABN) postoperatively. In one, symptom disappeared spontaneously 2 months after surgery; the other had re-operation due to continuous symptom. In this case, neuroma was recognized at the one branch of MCABN.

SUMMARY POINTS  EAUNRAT is less invasive and reliable maneuver; short and middle term results are satisfactory.  It is easy to perform without using any specific equipment if surgeon is familiar with anatomy and scope operation.  Surgeons need to mind cases of contraindication for this procedure, for example revision surgery, space-occupying lesions, a scarred and adherent nerve.

REFERENCES 1 Hoffmann R, Siemionow M. The endoscopic management of cubital tunnel syndrome. J Hand Surg Br. 2006;31:23–29. 2 Konishiike T, Nishida K, Ozawa M, et al. Anterior transposition of the ulnar nerve with endoscopic assistance. J Hand Surg Eur. 2011;36:126–129. 3 Jiang S, Xu W, Shen Y, et al. Endoscopy-assisted cubital tunnel release under carbon dioxide insufflation and anterior transposition. Ann Plast Surg. 2012;68:62–66. 4 Morse LP, McGuire DT, Bain GI. Endoscopic ulnar nerve release and transposition. Tech Hand Up Extrem Surg. 2014 Mar;18(1):10-4.

FIGURES

Guest Society Poster 75: Outcome of the Carpal Tunnel Release for Patients Older Than 80 Years of Age

AUTHORS Hidemasa Yoneda, MD Akimasa Morita, MD Kouzou Fujisawa, MD. PhD Shinsuke Takeda, MD Masahiro Tatebe, MD Hitoshi Hirata, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve PURPOSE/CATEGORY - Treatment;Therapy/Rehabilitation;Prognosis/Outcomes LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Amongst aging population, the instances of senior people who are performed surgery for carpal tunnel syndrome are increasing, but the results of surgical procedure to the elder people are not well known. In this study we retrospectively evaluated the outcome of the carpal tunnel release for patients older than 80 years of age.

METHODS We reviewed all the patients older than 80 years who were diagnosed as a carpal tunnel syndrome and received an operation in the past 5 years in our institute. We excluded patients who were performed an opponensplasty. Ultimately we reviewed 22 wrists of 14 patients (12 patients women, 2 patients men) who were conducted only a carpal tunnel release. They were followed for at least 3 months. We evaluated the following items preoperatively and postoperatively. Subjectively, numbness and nocturnal pain of the affected hand, handling chopsticks and buttoning a cloth were evaluated. Objectively, we examined Phalen’s test, Tinel’s sign of the carpal tunnel and measured tip pinch power. We also surveyed Hand 20 as a patient based outcome.

RESULTS The mean age of the patients were 84 years old (range 80 - 92). Preoperatively 4 wrists showed nocturnal pain and all are relieved postoperatively. Although Pharen’s test were positive in 2 wrists that were negative at the final examination, Tinel’s sign demonstrated in 8 wrists remained positive after the operation. Two patients who were unable to handle chopsticks were acquired ability to use postoperatively, but 8 patients who were unable to button a cloth still needed assistance for the action after the operation. Average of Hand 20 was 51 points preoperatively, which was significantly improved postoperatively (41 points). Average of the tip pinch power at 1 year after the operation was not different statistically from the preoperative measurement.

SUMMARY POINTS  Elderly patients who received surgery tended to demonstrate numbness of the wrist and inability of the oppose thumb preoperatively, but they did not have the nocturnal pain and it did not trigger the operation compared with younger patients.  Although patient based outcomes were improved, inconvenience of buttoning a cloth and numbness of the affected wrist were not improved after the operation.  Considering improvement of the tip pinch power was not remarkable at 1 year after the operation, patients who could not oppose thumb should be treated with an opponenseplasty rather than just a carpal tunnel release.

REFERENCES 1 J Hand Surg Am. 2014 2188-91. Electrophysiological assessment of carpal tunnel syndrome in elderly patients: one-year follow-up study. 2 J Hand Surg Am. 2013 1524-9. Clinical outcomes of endoscopic carpal tunnel release in patients 65 and over.

Guest Society Poster 76: MRI Analysis of Carpal Tunnel Syndrome in Hemodialysis Patients Compared to Non-Hemodialysis Patients

AUTHORS Koji Fujita, MD Kenji Kimori, MD Yutaka Kadonishi, MD Hiroki Yamanaka, MD Dr. Yoshikazu Ikuta, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Nerve;Systemic diseases and disorders PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Carpal tunnel syndrome (CTS) is common among patients receiving hemodialysis and deeply influences the daily life. Amyloid deposits are considered as the main reason for median nerve compression but the prevalence is unclear. Therefore, to determine the main region of amyloid deposit inside carpal tunnel, we measured cross-sectional area (CSA) of each composition of carpal tunnel on preoperative MRI.

METHODS 41 hands from 33 hemodialysis patients (HD), and 41 hands from 36 age- and sex-matched non- hemodialysis patients (NHD), who underwent primary surgery for CTS in Tsuchiya General Hospital (Hiroshima, Japan) from 2005 to 2015, were retrospectively collected. CTS was diagnosed from clinical and electromyographic (EMG) findings. CSA of carpal tunnel, each flexor tendon and median nerve at the level of hook of hamate were measured in T1 weighted axial image on preoperative MRI, by using Synapse OP-A software. Statistical analysis was performed by Student’s t-test and Pearson's chi-squared test. This study was approved by Institutional Review Board.

RESULTS HD patient age was 64.3 years and the dialysis duration was 21.9 (11-35) years, and NHD patient age was 65.5 years. CSA of carpal tunnel (P = 0.01), flexor tendon (P = 0.03) and flexor digitorum profundus tendon (FDP) (P = 0.02) were bigger in HD group, but median nerve, flexor digitorum superficialis tendon and flexor pollicis longus tendon were not significantly different from NHD group. Hemodialysis duration or age did not show any strong correlation to each CSA. In one dialysis patient, accessory tendon of FDP was dissected during the surgery to reduce the pressure of carpal tunnel, and then it was histologically analyzed. Amyloid deposition was confirmed not only around but inside the tendon itself by Dylon stain.

SUMMARY POINTS  Hemodialysis caused expansion of carpal tunnel due to amyloid deposition as previously described.  Hemodialysis also caused expansion of flexor tendon, especially FDP, possibly because amyloid deposited inside the tendon. We could not identify why it mostly happened to FDP.  Duration of hemodialysis or age did not correlate to any CSA. Great progress on Beta 2- microglobulin removal technique could be one of the reasons.

REFERENCES 1. Carpal tunnel syndrome: a major complication in long-term hemodialysis patients. 2. Amyloid and non-amyloid carpal tunnel syndrome in patients receiving chronic renal dialysis.

FIGURES

Guest Society Poster 77: Surgical Outcome of Dupuytren's Contracture

AUTHORS Taiichi Matsumoto, MD Takuya Tsumura, MD Kazumasa Takayama, MD Takanori Hayashi, MD Hiroyuki Doi, MD Hayao Shiode, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Systemic diseases and disorders PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Several procedures have been used in the treatment of Dupuytren's contracture, such as multiple Z-plasty, the open palm technique, flaps, partial fasciectomy, and collagenase injections (Xiaflex). Xiaflex was recently launched in Japan. The purpose of this study was to compare the efficacy of these procedures in the treatment of Dupuytren's contracture.

METHODS A total of 76 fingers of 46 patients were studied (40 men, 6 women; mean age 65.2±6.2y). Both hands were involved in 4 patients, the right hand in 27, and the left in 15; there were 38 little fingers, 26 ring fingers, 8 long fingers, 2 index fingers, and 2 thumbs. There were 31 fingers in the multiple Z-plasty group, 13 in the flap group, 6 in the open palm group, 9 in the partial fasciectomy group, and 18 in the Xiaflex group. Preoperative severity was graded using the Meyerding classification (a); postoperative outcome was assessed by Tonkin’s percentage improvement in extension (b); and Tubiana’s criteria (c) were used for preoperative -> postoperative staging. In addition, deteriorated cases of insufficient postoperative proximal interphalangeal joint (PIP) extension angle were investigated.

RESULTS  Multiple Z-plasty: (a) 2.1, (b) 58.5%, (c) preoperative stage 2.0 -> postoperative 1.3.  Flap: (a) 2.5, (b) 75.4%, (c) 2.6 -> 1.3.  Open palm: (a) 2.0, (b) 72.3%, (c) 2.2 -> 1.2.  Partial fasciectomy: (a) 3.5, (b) 79.2%, (c) 1.3 -> 1.0.  Xiaflex: (a) 2.4, (b) 98.6%, (c) 1.7 -> 1.1.  In the flap and multiple Z-plasty groups, there were deteriorated cases of insufficient postoperative PIP extension angle.  Improved flap group: PIP preoperative extension angle was -56.6°, and postoperative, - 8.6°.  Deteriorated flap group: PIP preoperative extension angle was -19.2°, and postoperative, -42.2°.  Improved multiple Z-plasty group: PIP preoperative extension angle was -47.8°, and postoperative, -20.7°.  Deteriorated multiple Z-plasty group: PIP preoperative extension angle was -21.0°, and postoperative, -36.3°.

SUMMARY POINTS  Tonkin’s percentage improvement in extension was good in the flap, open palm, and Xiaflex groups.  Flap and multiple Z-plasty procedures in mild PIP contracture cases should be conservative, because contractures may deteriorate.  The open palm and Xiaflex procedures, however, are approved for treatment of Dupuytren's contracture, even if a PIP contracture is mild. In mild PIP contracture cases, there is a significant difference in the results, depending on the procedure.

REFERENCES 1. J Hand Surg Am. 1984 Jan;9A(1):53-8. Fasciectomy and Dupuytren's disease: a comparison between the open-palm technique and wound closure. Lubahn JD, Lister GD, Wolfe T. 2. J Hand Surg Eur Vol. 2009 Feb;34(1):90-3. The lateral digital flap for Dupuytren's fasciectomy at the proximal interphalangeal joint--a study of 84 consecutive patients. Anwar MU, Al Ghazal SK, Boome RS. 3. J Hand Surg Am. 1992 Mar;17(2):312-7. Prognosis in Dupuytren's disease. Adam RF, Loynes RD.

FIGURES

Guest Society Poster 78: Comparing Surgical Outcomes for Mucous Cysts between Simple Capsulectomy and Local Skin Flap Coverage

AUTHORS Koji Shigematsu, MD, PhD Mitsuyuki Nagashima, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Systemic diseases and disorders PURPOSE/CATEGORY - Treatment LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Surgical treatment of mucous cysts remains controversial regarding whether local flap coverage after resection of thinned skin is required or not. We hypothesized that simple resection of the cyst and the osteophyte is sufficient for the treatment of mucous cysts, and retrospectively compared the clinical results between simple resection of the cyst (S) and local flap coverage after resection of thinned skin (F).

METHODS Study 1: Retrospective comparison of surgical results between S and F procedures. Both procedures were combined with osteophyte osteotomy. From 2008 to 2010, 15 patients (male, 1; female, 14; mean age at surgery, 59 years) who underwent the F procedure were included. Further, from 2010 to 2011, 16 patients (male, 2; female, 14; mean age at surgery, 59 years) who underwent the S procedure were included. Evaluation factors comprised the recurrent ratio, period of wound healing, and complications. Differences were analyzed using the Student’s t- test. Significance was set at P < 0.05.

Study 2: Clinical outcomes for the S procedure. A total of 64 patients (male, 4; female, 60; mean age at surgery, 56 years) underwent the S procedure from 2010 to 2015. Here we report a retrospective analysis, its outcomes, and complications associated with this procedure.

RESULTS Study 1: The mean age at surgery, gender, cyst size were statistically similar in both groups. The recurrent ratio was 0% (0/16) and 6.7% (1/15) for the S and F procedures, respectively. Periods of wound healing were significantly shorter for the S (average, 11 days) than for the F (average, 14 days). Two episode of distal skin hypersensitivity of the operative digits was confirmed in both groups, but these improved within 6 months. There was no infection and skin necrosis.

Study 2: All patients who received the S procedure were successfully treated; however, two case was recurrent the cyst (the recurrent ratio, 3.1% (2/64). Range-of-motion of the affected digits recovered within 6 months, but at latest follow up, it decreased, most likely due to advanced osteoarthritis change of the distal interphalangeal joint.

SUMMARY POINTS  Surgical outcomes for digital mucous cyst were similar using both the S and F procedures.  However, wound healing period for the S procedure was significantly shorter than that for the F procedure. For simplicity the surgical procedure of mucous cyst, we conclude that simple resection of the cyst and osteophyte is sufficient.  We further plan to investigate whether the osteophyte osteotomy is necessary or not.

REFERENCES 1. Kanayama K, Wada T, Iba K et al. Total dorsal capsulectomy for the treatment of mucous cyst. J Hand Surg. Am 2014;39:1063-1067.

FIGURES

Guest Society Poster 79: The Seasonal Feature of the Mycobacterium Marinum Tenosynovitis of the Hand in Japan

AUTHORS Yasuhiro Yamamoto, MD, MD Akira Hara, MD, PhD Satoshi Ichihara, MD, PhD Kouichi Kusunose, MD, PhD Hajime Kajihara, MD, PhD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - International Perspectives PURPOSE/CATEGORY - International LEVEL OF EVIDENCE: Level 4

HYPOTHESIS Mycobacterium marinum (M.marinum) is an atypical mycobacteria that is ubiquitously found in aquatic environments. M. marinum grows optimally at 30°C but poorly or not at all at 37°C. It causes only local lesions affecting cooler body surfaces usually of the extremities, particularly the hands, but not typically the disseminated disease. We reviewed the influence of sea water temperature and air temperature in the outbreak of M.marinum in Japan.

METHODS Database of Japan Medical Abstracts Society was searched using the key words ‘Mycobacterium marinum’ and ‘tenosynovitis’. Injury in aquatic environment, onset and outbreak of the illness were reviewed. The mean monthly temperature of sea water and the mean monthly air temperature in the past were checked on the website of Japan Meteorological Agency.

RESULTS Thirty-seven cases of M.marinum tenosynovitis of the hand including our 7 cases were detected. All of the reported hospitals were located near the sea of the western Japan, and it was never seen in the northeastern or Hokkaido prefecture or Okinawa prefecture. The patients who have previous history of injury occurring in an aquatic environment of the sea and likely were infected through the injury represented 18 cases. Among them, the date of injury was described in 11 cases. Eight of 11 cases were in October or November. The date of the first visit to the reported hospitals was described in 19 cases. December, January and February (winter season) were frequent (14 cases); especially 7 cases were seen presenting in February. No cases were seen during the summer. Although the mean temperature of sea water at the injury was 15 to 24°C the mean air temperature was 7.6 to 19.8°C, which was about 6°C lower than the sea water temperature.

SUMMARY Considering human infection from a fish source, we assumed that since M.marinum grew at the sea environment in summer (August and September), then infection to human from fish has occurred in October or November. Accordingly, as the air temperature was going down, the temperature of the hand or finger in human body was closer to optimal growth temperature of M.marinum in winter (December, January and February). People came to hospital in the winter because of progressed symptoms.

REFERENCES 1. Clark &Shepard. Generation times of M. marinum in 7H9 broth, , J Bacteriol 1963

Guest Society Poster 80: Can the JAMAR Hydraulic Hand Dynamometer Detect Malingering Patients?

AUTHORS Tadahiro Nakajima, MD Kaoru Tada, MD Daiki Yamamoto, MD Hiroyuki Tsuchiya, MD

The authors of this poster have nothing of financial value to disclose.

CURRICULUM TOPIC - Practice Management PURPOSE/CATEGORY - Evaluation/Diagnosis LEVEL OF EVIDENCE: Level 3

HYPOTHESIS Malingering patients can be identified with the five-rung grip test using the JAMAR Hydraulic Hand Dynamometer.

METHODS We evaluated 50 handgrips of 50 healthy individuals and 67 handgrips of 50 symptomatic individuals who had complaints about their upper extremities. The symptomatic cases comprised 16 cases of trauma, 14 cases of peripheral nervous system disorders, 8 cases of central nervous system disorders, 3 cases of degenerative diseases, other 5 cases, and 4 cases of unknown cause. The subjects were instructed to sit on a chair with their shoulders in an intermediate position and elbows flexed at 90 degrees and to exert full effort while in grip positions from 1.0, 1.5, 2.0, 2.5, and 3.0 inches. A 5-second rest period was allowed after each five-step measurement. The mean score and standard deviation for each grip were calculated. Standards for grip values have shown the maximum value at the setting of grip 2 or 3, and the minimum value at the setting of grip 1 or 5 creating a “bell-shaped curve.” Based on these facts, the grip test results of malingering patients should not present a curved distribution.

RESULTS The scores (mean ± SD, in kg) for grips 1, 2, 3, 4, and 5 were 29.15 ± 9.61, 35.36 ± 10.50, 34.47 ± 9.60, 31.25 ± 9.78, and 24.26 ± 7.74, respectively, for the healthy cases and 11.54 ± 7.14, 17.46 ± 8.19, 16.19 ± 8.17, 13.25 ± 7.13, and 10.23 ± 6.45, respectively, for the symptomatic cases. A “bell-shaped curve,” which peaked at the maximum at grip 2 or 3, was obtained for all the cases, except for the three symptomatic cases. In the three symptomatic cases, we strongly suspected a psychogenic element that showed that the strength of each grip was unchanged or decreased as grip width expanded. One of the patients who did not fit within the “bell-shaped curve” for grip strnegth had contradicting neurological findings in the medical examination. The two additional patients who fell outside the curve complained of numbness and muscle weakness of the upper extremities and had contradicting neurological findings.

SUMMARY

The five-rung grip test using the JAMAR Hydraulic Hand Dynamometer is a simple and useful screening test for malingering patients. The symptoms of the patients whose test result distributions plateaued or declined as grip width expanded were suspected to be caused by psychogenic elements.