Paper #9 - Posterior shoulder instability in throwing athletes: a case-matched comparison of throwers and non-throwers

Abstract

Introduction: The purpose of this study was to evaluate the results of arthroscopic capsulolabral repair for the treatment of posterior shoulder instability in a throwing athlete cohort when compared to non-throwers. Methods and Materials: Forty-eight overhead throwing athletes undergoing arthroscopic posterior capsulolabral reconstruction were case matched with 48 non-throwing athletes. These cohorts were followed as they underwent posterior capsulolabral reconstruction by measuring shoulder pain, function, return to sport, and operative failures. Operative details such as intra-articular pathology and repair construct were also recorded. Results: At a mean follow up of 37 (range 12-97) months post-operatively, no statistical differences were noted between throwers and non-throwers regarding ASES scores, stability, strength, or range of motion between throwers and non-throwers. Sixty percent of throwing athletes were able to return to their pre-injury level of competitive throwing. Throwers with a discreet labral tear intra-operatively had a 10-fold increased likelihood to return to sport (OR 9.6, p = .012). Similarly, throwers that had suture anchors constructs showed a 10-fold increased likelihood of return to play compared to anchor-less repairs (OR 9.6, p = .012). Non-throwers showed no variability by labral findings or fixation techniques. Pitchers had equivocal outcomes scores when compared to other throwers, but had poorer return to play rates (50% versus 60% full return, respectively). Conclusions: Arthroscopic capsulolabral plication for unidirectional posterior shoulder instability is an effective treatment for overhead throwing athletes. Intra-operatively, achieving an adequate capsular plication and stabilizing the repair via suture anchors will give this athletic population the best odds at returning to competitive sports. Significance: Comparison study; Level of evidence, 3. This is the first study directly comparing outcomes of posterior shoulder instability managed with arthroscopic stabilization between throwing and non-throwing athletes. It is also the largest series focusing on throwing athletes reported to date.