Failure Rates After Revision Arthroscopic Stabilization for Recurrent Anterior Shoulder Instability Based on Anterior Capsulolabral Complex Conditions

Abstract

Background: A labral retear is an important contributing factor to surgical failure after arthroscopic soft tissue stabilization for recurrent anterior shoulder instability. However, surgeons frequently encounter poor tissue conditions in the anterior capsule, such as capsular tears, during revision surgery. Purpose: To analyze the clinical outcomes and failure rates of revision arthroscopic stabilization after failed Bankart repair based on the tissue conditions of the anterior capsule and the labrum. Outcomes were compared for revision after failed Bankart repair because of a labral retear versus a healed labrum but with capsular tears. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 55 patients who underwent revision arthroscopic stabilization after failed Bankart repair were included. Revision surgery was indicated if patients had a history of recurrent instability with positive apprehension test results, regardless of magnetic resonance imaging (MRI) findings of a labral retear. Patients were allocated into 2 groups based on arthroscopic findings at the time of revision surgery: group 1 consisted of patients who had a healed labrum with definite anterior capsular tears, and group 2 comprised patients who had labral retears without capsular tears. Clinical outcomes were assessed using the American Shoulder and Elbow Surgeons score, Rowe score, and surgical failure rate. Results: Overall, 10 patients were included in group 1, and 45 patients were included in group 2. No capsular tears were detected on preoperative MRI or magnetic resonance arthrography scans in either group, whereas all patients in group 2 had evidence of anterior labral retears on imaging scans. After revision surgery, 9 patients (16.4%) showed surgical failure by 25.6 months postoperatively. Patients in group 1 had a significantly higher surgical failure rate than did those in group 2 (4 patients [40.0%] vs 5 patients [11.1%], respectively; P = .04). The incidence of capsular tears was significantly higher in patients with surgical failure versus those without surgical failure (44.4% vs 13.0%, respectively; P = .04). Conclusion: A capsular tear of the anterior capsulolabral complex was an important indicator for surgical failure after revision arthroscopic stabilization. If patients demonstrate symptomatic instability after arthroscopic soft tissue stabilization without evidence of labral retears on imaging scans, an anterior capsular tear should be considered as a possible factor for recurrence.