Mid-term results of reverse shoulder arthroplasty for glenohumeral osteoarthritis with posterior glenoid deficiency and humeral subluxation

BACKGROUND: Results of anatomic shoulder arthroplasty for glenohumeral osteoarthritis with severe glenoid retroversion are unpredictable with a high rate of glenoid loosening. Reverse shoulder arthroplasty (RSA) has been suggested as an alternative, with good early results. We sought to confirm this at longer follow-up (minimum 5 years). The study hypothesis was that early results would endure over time.

METHODS: We retrospectively reviewed all RSAs performed in 7 centers from 1998 to 2010. The inclusion criteria were primary glenohumeral osteoarthritis with B1, B2, B3, or C glenoid. Forty-nine shoulders in 45 patients fulfilled the criteria. Bone grafting was performed in 16 cases. Clinical outcomes were evaluated with the Constant score (CS) and shoulder range of motion.

RESULTS: The mean total CS increased from 30 preoperatively to 68 points (P < .001) with significant improvements in all the subsections of the CS and range of motion. Scapular notching was observed in 20 shoulders (43%), grade 1 in 5 (11%), grade 2 in 7 (15%), grade 3 in 5 (11%), and grade 4 in 3 (6%). The glenoid bone graft healed in all the shoulders. Partial inferior lysis of the bone graft was present in 8 cases (50%). Scapular notching and glenoid bone graft resorption had no influence on the CS (P = .147 and P = .798).

CONCLUSION: RSA for the treatment of primary glenohumeral osteoarthritis in patients with posterior glenoid deficiency and humeral subluxation without rotator cuff insufficiency resulted in excellent clinical outcomes at a minimum of 5 years of follow-up.