Outcomes of Arthroscopic Posterior Shoulder Stabilization in the Beach-Chair Versus Lateral Decubitus Position: A Systematic Review

Background: Arthroscopic posterior shoulder stabilization can be performed with patients in the beach-chair (BC) and the lateral decubitus (LD) positions; however, the impact of patient positioning on clinical outcomes has not been evaluated. Purpose: To compare clinical outcomes and recurrence rates after arthroscopic posterior shoulder stabilization performed in the BC and LD positions. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review using PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines was performed by searching PubMed, Embase, and the Cochrane Library for studies reporting the clinical outcomes of patients undergoing arthroscopic posterior shoulder stabilization in either the BC or LD position. All English-language studies from 1990 to 2017 reporting clinical outcomes after arthroscopic posterior shoulder stabilization with a minimum 2-year follow-up were reviewed by 2 independent reviewers. Data on the recurrent instability rate, return to activity or sport, range of motion, and patient-reported outcome scores were collected. Study methodological quality was evaluated using the Modified Coleman Methodology Score (MCMS) and Quality Appraisal Tool (QAT). Results: A total of 15 studies (11 LD, 4 BC) with 731 shoulders met the inclusion criteria, including 626 shoulders in the LD position (mean patient age, 23.9 +/- 4.1 years; mean follow-up, 37.5 +/- 10.0 months) and 105 shoulders in the BC position (mean patient age, 27.8 +/- 2.2 years; mean follow-up, 37.9 +/- 16.6 months). There was no significant difference in the overall mean recurrent instability rate between the LD and BC groups (4.9% +/- 3.6% vs 4.4% +/- 5.1%, respectively; P = .83), with similar results in a subanalysis of studies utilizing only suture anchor fixation (4.9% +/- 3.6% vs 3.2% +/- 5.6%, respectively; P = .54). There was no significant difference in the return-to-sport rate between the BC and LD groups (96.2% +/- 5.4% vs 88.6% +/- 9.1%, respectively; P = .30). Range of motion and other patient-reported outcome scores were not provided consistently across studies to allow for statistical comparisons. Conclusion: Low rates of recurrent shoulder instability and high rates of return to sport can be achieved after arthroscopic posterior shoulder stabilization in either the LD or the BC position. Additional long-term randomized trials comparing these positions are needed to better understand the potential advantages and disadvantages of surgical positioning for posterior shoulder stabilization.