Posterior shoulder instability: Prospective non-randomised comparison of operative and non-operative treatment in 51 patients.

BACKGROUND: The management of posterior shoulder instability remains controversial. Consequently, for a symposium on this topic, the French Arthroscopy Society (SFA) conducted a prospective multicentre study comparing outcomes of operative and non-operative treatment.

OBJECTIVE: To compare outcomes after operative versus non-operative treatment of posterior shoulder instability.

HYPOTHESIS: The surgical treatment of posterior shoulder instability may achieve better clinical outcomes than non-operative treatment in selected patients.

MATERIAL AND METHODS: Fifty-one patients were included prospectively then followed-up for 12months. Three groups were defined based on the clinical presentation: recurrent dislocation or subluxation, involuntary instability or voluntary instability that had become involuntary, and shoulder pain with instability. Of the 51 patients, 19 received non-operative therapy involving a three-step rehabilitation programme and 32 underwent surgery with a posterior bone block, labral repair and/orcapsule tightening, or bone defect filling. At inclusion and at last follow-up, the Subjective Shoulder Value (SSV), Rowe score, Walch-Duplay score, and Constant score were determined.

RESULTS: The preliminary results after the first 12 months are reported here. In the non-operative and operative groups, the Constant score was 78 versus 87, the Rowe score 64 versus 88, and the Walch-Duplay score 69 versus 82, respectively. These differences were statistically significant (P<0.05).

DISCUSSION: To our knowledge, this study is the first comparison of non-operative versus operative treatment in a cohort of patients with documented posterior shoulder instability. Outcomes were better with operative treatment. However, this finding remains preliminary given the short follow-up of only 1 year.

LEVEL OF EVIDENCE: III, case-control study.