Arthroscopic versus Open Shoulder Stabilization for Recurrent Anterior Instability

BACKGROUND: Arthroscopic stabilization for anterior shoulder instability has been reported to result in a higher rate of recurrent instability compared to traditional open techniques. PURPOSE: To test the null hypothesis that there is no difference in the clinical outcomes in patients with recurrent anterior shoulder instability treated with open or arthroscopic stabilization. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A consecutive series of 64 patients with recurrent anterior shoulder instability were randomized to receive either arthroscopic or open stabilization by a single surgeon. Magnetic resonance arthrogram studies were obtained preoperatively. These findings were compared to arthroscopic findings. Postoperative evaluations included range of motion, stability, and subjective assessments including Single Assessment Numeric Evaluation, Simple Shoulder Test, Western Ontario Instability Index, and University of California, Los Angeles evaluation. Failure was defined as a second dislocation, recurrent subluxation, or symptoms precluding return to previous work or unrestricted active military duty. RESULTS: Sixty-one patients, 29 who received open stabilization and 32 who received arthroscopic stabilization, were evaluated at a mean of 32 months postoperatively (range, 24-48 months). Patient demographics were equivalent. Preoperative magnetic resonance arthrogram findings were confirmed at arthroscopic examination. The mean operative time was significantly shorter for the arthroscopic repairs (59 vs 149 minutes; P < .001). There were 3 clinical failures (2 open stabilizations, 1 arthroscopic stabilization) by the established criteria. There was a statistically significant improvement from preoperative to postoperative Single Assessment Numeric Evaluation scores in both groups (P < .001). The mean loss of motion (compared to the contralateral shoulder) was greater in the open shoulders. Subjective evaluations were equal in both groups. CONCLUSION: Clinical outcomes after arthroscopic and open stabilization were comparable. Preoperative magnetic resonance arthrograms in shoulders with anterior instability allow an accurate diagnosis of intra-articular abnormality that correlates well with operative findings. Arthroscopic stabilization for recurrent anterior shoulder instability can be performed safely; the clinical outcomes are comparable to those after traditional open stabilization.