Risk Factors for Progression to Glenohumeral Arthritis After Arthroscopic Anterior Stabilization in a Young and High-Demand Population

Background: While arthroscopic stabilization for anterior glenohumeral instability is successful in preventing recurrent dislocations, progression to glenohumeral arthritis remains concerning. Age, anchor number, and capsular volume shrinkage have been previously established as risk factors for progression to arthritis in patients who underwent arthroscopic anterior stabilization. However, the rate of and risk factors for arthritis in young populations have not been well characterized. Purpose: To evaluate the rate of progression to glenohumeral arthritis and identify potential risk factors after arthroscopic anterior stabilization in a young population. Study Design: Cohort study; Level of evidence, 3. Methods: This study included 287 patients who underwent an index primary arthroscopic anterior shoulder stabilization procedure at a single institution and had a minimum of 4 years of postoperative imaging available over a 12-year period. Patients were excluded if imaging or operative reports were unavailable. The presence of arthritis was defined using radiographic parameters. Kaplan-Meier survival curves were estimated for the development of arthritis and compared by patient characteristics using log-rank tests. Cox proportional hazard models were used to calculate hazard ratios (HRs) with 95% CIs associated with patient characteristics as predictors of the development of glenohumeral arthritis, adjusted for confounders identified in univariate analyses. Results: Among the 287 patients, 8% (23/287) developed glenohumeral arthritis. The mean patient age at the time of surgery was 22.7 years (SD, 5.26). The median time from surgery to diagnosis of arthritis was 8 years, and the median follow-up time was 9 years (interquartile range, 6-11). Kaplan-Meier curves revealed differences in time to arthritis among patient groups, with earlier arthritis observed when stratified by age >25 years, use of <3 anchors at index surgery, and undergoing revision surgery after index stabilization. Adjusted for potential confounders in a multivariable Cox regression model, risk factors for the development of glenohumeral arthritis included older age at index surgery (HR per 1-SD increase in years, 1.85 [95% CI, 1.34-2.55]), lower anchor number (HR, 1.54 [95% CI, 1.107-2.14]), and revision surgery (HR, 2.83 [95% CI, 1.150-.95]). Conclusion: Progression to glenohumeral arthritis after anterior stabilization occurred in 8% of a young patient population. The age and number of anchors used are statistically significant risk factors for progression to arthritis. Additionally, revision surgery was identified as a risk factor, which has not been previously reported in the literature.