Indications and outcomes of glenoid osteotomy for posterior shoulder instability: a systematic review

BACKGROUND: There is limited evidence examining glenoid osteotomy as a treatment for posterior shoulder instability. METHODS: A search of Medline, Embase, PubMed and Cochrane Central Register of Controlled Trials was conducted from the date of origin to 28th November 2019. Nine out of 3,408 retrieved studies met the inclusion criteria and quality was assessed using the Methodological Index for Non-randomized Studies tool. RESULTS: In 356 shoulders, the main indication for osteotomy was excessive glenoid retroversion (greater than or equal to approximately −10°). The mean preoperative glenoid version was −15° (range, −35° to −5°). Post-operatively, the mean glenoid version was −6° (range, −28° to 13°) and an average correction of 10° (range, −1° to 30°) was observed. Range of motion increased significantly in most studies and all standardized outcome scores (Rowe, Constant–Murley, Oxford instability, Japan Shoulder Society Shoulder Instability Scoring and mean shoulder value) improved significantly with high rates of patient satisfaction (85%). A high complication rate (34%, n = 120) was reported post-surgery, with frequent cases of persistent instability (20%, n = 68) and fractures (e.g., glenoid neck and acromion) (4%, n = 12). However, the revision rate was low (0.6%, n = 2). CONCLUSION: Glenoid osteotomy is an appropriate treatment for posterior shoulder instability secondary to excessive glenoid retroversion. However, the high rate of persistent instability should be considered when making treatment decisions. Level of Evidence: Systematic review; Level 4