MID-AMERICA ORTHOPAEDIC ASSOCIATION 31 st Annual Meeting April 17-21, 2013 Omni Amelia Island Resort Amelia Island, FL Podium and Poster Abstracts NOTE: Disclosure information is listed at the end of this document. MAOA FIRST PLENARY SESSION April 18, 2013 1. Long-Term Outcomes of Modified Eden-Lange Tendon Transfer for Symptomatic Trapezius Paralysis from Spinal Accessory Nerve Injury Eric R. Wagner, M.D. Rochester, MN *Basseem T. Elhassan, M.D. Rochester, MN PURPOSE: The purpose of this study is to evaluate the outcome of multiple tendon transfers to the scapula to stabilize the scapulothoracic articulation in the treatment of symptomatic trapezius paralysis. METHODS: Thirteen patients, with average age of 25 years, had a history of trapezius paralysis secondary to spinal accessory nerve injury that failed to recover spontaneously or after nerve repair. The indications for surgery included shoulder pain and weakness and limited range of motion of the shoulder, specifically shoulder abduction. All patients underwent triple tendon transfer, including transfer of the levator scapulae with its bony insertion to the lateral aspect of the spine of the scapula, rhomboid minor with its bony insertion to the spine of the scapula just medial to the levator scapulae insertion, and rhomboid major tendinous insertion to the medial spine of the scapula and superomedial aspect of the infraspinatus fossa. All patients had a CT scan and ultrasound done at brace removal and beyond one year. RESULTS: At an average follow-up of 25 months (15-35), all patients had improvement of neck asymmetry, restoration of the scapula position compared to the opposite site, and no evidence of winging. All patients had significant improvement of pain from 12 of 13 patients reporting pain as moderate or severe before the operation to 2 of 13 after the operation (p<0.01). Improvements in range of motion included active shoulder abduction from average 71 o preoperatively to 108 o postoperatively (p<0.02) and shoulder flexion from average 102 o to 140 o (p<0.01). The aggregate shoulder Constant Score from 41, with a relative score of 49% preoperatively to 63, with a relative score of 70% postoperatively (p<0.01). The shoulder subjective value was 44% preoperatively to 67% postoperatively (p<0.01). The DASH score improved from 55 to 21 after the operation (p<0.01). CT scans demonstrated bony healing; beginning as early as eight weeks postoperatively, while ultrasound demonstrated successful muscle contraction in the line of the transfer. All patients were very satisfied with the outcome of surgery and reported their shoulder as better or significantly better than preoperatively. CONCLUSIONS: Multiple tendon transfers to the scapula to try to restore the function of the trapezius appear to be effective in stabilizing the scapulothoracic articulation and restoring the function of the trapezius, which in turns lead to significant improvement of pain and shoulder function. 2. Comparative Effectiveness of Prophylactic Antibiotic Choice and Surgical Infection in Arthroplasty Brent A. Ponce, M.D. Birmingham, AL *Benjamin Todd Raines, MA, ATC Birmingham, AL Catherine Vick, M.P.H., M.T. (ASCP ) Birmingham, AL Joshua Richman, M.D. Birmingham, AL Mary Hawn, M.D. Birmingham, AL INTRODUCTION: Prophylactic antibiotics (PA) decrease surgical site infections (SSI). Recent studies have failed to show improved SSI rates with adherence to the Surgical Care Improvement Project (SCIP) measures. The aim of this study is to identify the comparative effectiveness of the SCIP approved antibiotics for SSI prevention. METHODS: This is a retrospective cohort study using national Veteran’s Administration (VA) data on patients undergoing elective primary or revision hip or knee arthroplasty from 2005 to 2009. Data on the type of PA used was merged with VA Surgical Quality Improvement Program data to identify SSI as well as patient and procedure risk factors. Patients were stratified by documented penicillin (PEN) allergy, and SSI rates were compared among patients receiving vancomycin (VANC) alone versus other SCIP-approved PA using chi-square tests. The overall low event rate precluded reliable adjustment for covariates. RESULTS: A total of 16,568 arthroplasties were included in the cohort. PA use distribution: 81.2% received a 1 st generation cephalosporin (CF1), 8.3% VANC, 5.8% VANC + CF1, and 4.7% clindamycin (CLINDA). A documented PEN allergy accounted for 52.9% of patients receiving VANC, and 95.0% of those receiving CLINDA. The overall 30-day observed SSI rate was 1.5%. Unadjusted SSI rates by PA were: 2.6% with VANC alone, 1.5% with VANC + CF1, 1.4% with CF1, and 1.0% with CLINDA. Unadjusted analysis among patients with documented PEN allergy revealed an SSI frequency of 2.1% with VANC prophylaxis compared to 1.0% for CLINDA (Chi-square p=0.12). For patients without PEN allergy, SSI rate of 3.3% for VANC prophylaxis compared to 1.6% for VANC + CF1 (p=0.04) and 1.4% for CF1 alone (p<0.001). CONCLUSION: Factors other than PEN allergy, such as concern for MRSA or practice style, significantly influence the choice of VANC administration. Higher SSI rates observed with VANC as the sole PA suggest that VANC may not be an optimal PA. These data suggest that CLINDA is more effective in patients with PEN allergy and when there is concern for MRSA, VANC should be used in conjunction with a CF1 . 3. Randomized Clinical Trial Comparing Acetabular Cup Insertion: Patient Specific vs. Standard Surgical Instrumentation♦ *Travis J. Small, D.O. Cleveland, OH Viktor E. Krebs, M.D. Cleveland, OH Robert M. Molloy, M.D. Cleveland, OH Travis H. Smith, D.O. Cleveland, OH Jason Bryan, M.S. Cleveland, OH Alison K. Klika, M.S. Cleveland, OH Amar Mutnal, M.D. Cleveland, OH Wael K. Barsoum, M.D. Cleveland, OH INTRODUCTION: Success of total hip arthroplasty (THA) relies largely upon placement of the acetabular cup. Current imaging and preoperative planning are imprecise and unreliable. Severe pathology and less experienced surgeons can give rise to malpositioned cups leading to dislocation, impingement, and increased wear. The purpose of this study was to determine if a three-dimensional software program for preoperative planning combined with Acetabular Positioning System (APS) instrumentation improves placement of acetabular cups compared to standard imaging and surgical instrumentation (STD) in THA. METHODS: Three fellowship-trained surgeons performed THAs (various approaches) on 36 patients randomized into STD (n=18) or APS (n=18) technique. Preoperative CT scans were obtained on all patients and converted to the 3-D software program. All cases were preoperatively planned; APSs were manufactured for APS surgeries only. For STD cases, the patient’s surgery was completed using traditional techniques and instrumentation. All patients received postoperative CT scans to compare the planned to actual results. APS and STD cases were compared using absolute values and deviation from plan in planes of abduction and anteversion. RESULTS: Mean anteversion for the 18 APS cases was 18.54° ± 7.85°, and mean abduction was 46.4° ± 7.07°. Mean anteversion for the 18 STD cases was 28.44° ± 7.86° and mean abduction was 43.98° ± 9.03°. The differences found between the planned versus actual anteversion were -0.22° ± 6.95° (APS) and -6.89° ± 8.92° (STD). The differences between planned and actual abduction were -1.96° ± 7.28° (APS) and 1.27° ± 9.07° (STD). Difference in the means of anteversion in PSI versus STD was significant (p=0.0176); while differences in means abduction differences were not significant (p=0.246). CONCLUSIONS: The use of APS instruments resulted in significantly greater anteversion accuracy and precision than STD instruments. Abduction accuracy and precision was similar in each group. 4. Factors Associated with Nonunion in 100 Consecutive Type 2 and Type 3 Odontoid Fractures in Elderly Patients Michael T. Merrick, M.D. Grand Rapids MI *Casey L. Smith, M.D. Grand Rapids, MI Debra L. Sietsema, Ph.D., R.N. Grand Rapids, MI Tan Chen, M.S. Grand Rapids, MI Tammy Beckett, R.N. Grand Rapids, MI Clifford B. Jones, M.D. Grand Rapids, MI James R. Stubbart, M.D. Grand Rapids, MI Scott S. Russo, M.D. Grand Rapids, MI SUMMARY: Factors predictive of nonunion in older patients with odontoid fractures include: type 2 odontoid fractures, posteriorly displaced fractures, nonoperative treatment, males, and low-energy mechanisms. INTRODUCTION: Odontoid fractures are the most common cervical spine injury in older adults and have high rates of morbidity and mortality. The purpose of this study was to determine factors that were predictive of nonunion in odontoid fractures. METHODS: Between 2002 and 2011, 100 consecutive patients, age 50 years and over, with type 2 and type 3 odontoid fractures were treated at a single Level I trauma center, were followed in a single private practice, and retrospectively evaluated. Radiographs were reviewed and fusion was determined by flexion/extension x-rays, CT scan, or both. Nineteen mortalities were excluded from the fusion analysis. RESULTS: The overall fusion rate in the 81 patients who were living at their last follow-up was 74.1%. Type 2 odontoid fractures had a fusion rate of 66.1% compared to 92.0% of type 3 odontoid fractures (x 2=0.014). Lower rates of fusion were seen in patients with posteriorly displaced fractures (30/47, 63.8%) than with nondisplaced and anteriorly displaced fractures, (30/34, 88.2%), (x 2=0.047). Patients treated with nonoperative management had a lower rate of fusion (39/59, 66.1%) compared to patients who were treated with surgery (21/22, 95.5%), (x 2=0.007). Males had a lower fusion rate (19 of 32, 59.4%) than females (41 of 49, 83.7%), (x 2=0.015).