Paper #48 – Risk factors for subsequent instability or revision surgery following arthroscopic bankart repair

Background: Factors contributing to recurrent instability and revision stabilization procedures after isolated arthroscopic stabilization of anterior glenohumeral instability have not been examined in a Statewide cohort. Additionally, practice patterns of the management of the failed Bankart repair are unclear. We sought to identify the type, rate and risk factors associated with subsequent ipsilateral shoulder procedures in a large cohort of individuals undergoing arthroscopic stabilizations for anterior shoulder instability. Methods: The New York State Department of Health's Statewide Planning and Research Cooperative Systems (SPARCS) database was examined from 2003 to 2011 to identify all patients with a primary diagnosis of anterior shoulder instability (ICD-9-CM codes 831.01, 718.81 and 718.31) undergoing outpatient arthroscopic capsulorraphy (CPT code 29806). Patients younger than 10 or older than 60 years of age, and entries with missing data, were excluded. Patients were longitudinally followed for a minimum of three years (through 2014). Baseline demographics and all subsequent ipsilateral outpatient shoulder procedures were collected. SAS version 9.3 (Cary, NC) was used for data collection and statistical analysis. Results: We identified 5,719 unique patients who met the inclusion criteria. Mean patient age was 24.9 + /− 9.3 years, and 70.2% of the sample was male. A total of 461 (8.1%) patients underwent subsequent ipsilateral shoulder instability interventions a mean of 31.5 + /− 23.8 months after the initial stabilization procedure (2.1% had closed reduction alone; 6.0% had repeat instability surgery + /− closed reduction). Repeat arthroscopic capsulorraphy was the most common subsequent procedure (48.8%). Patients undergoing procedures for subsequent shoulder instability were younger (22.6 + /− 8.6 vs. 25.1 + /− 9.4 years of age, P < .001). Evidence of additional instability following arthroscopic Bankart was independently associated with age 19 years or younger (HR 1.82; 95% CI 1.50-2.21; P < .001), Caucasian ethnicity (HR 1.38; 95% CI 1.11-1.71; P = .003), evidence of bilateral shoulder instability (HR 1.54; 95% CI 1.06-2.23; P = .023) and a history of closed reduction(s) prior to initial arthroscopic Bankart repair (HR 2.45; 95% CI 1.90-3.15 P = < .001). Gender and surgeon volume was not associated with subsequent instability procedures. When follow-up was normalized to three years to allow for between year comparisons, year of surgery did not predict subsequent shoulder instability. Conclusion: Patients undergoing arthroscopic stabilization of anterior glenohumeral instability in New York State had an 8.1% chance of undergoing subsequent ipsilateral instability procedures. Younger age, Caucasian race, bilateral glenohumeral instability and closed reduction prior to initial Bankart repair were independent risk factors for additional instability procedures. The most common second surgical procedure was a repeat arthroscopic stabilization (Table 1). Table 1Multivariate analysis identifying independent risk factors for subsequent instability after Arthroscopy Bankart Odds Ratio 95% CI P value Age Younger age vs Older 1.86 1.53-2.26