High tuberosity healing rate associated with better functional outcome following primary reverse shoulder arthroplasty for proximal humeral fractures with a 135° prosthesis

BACKGROUND: Reverse shoulder arthroplasty (RSA) is a common treatment for proximal humeral fractures. (PHF) in the elderly. This study evaluates the functional outcome and the influence of. tuberosity healing (TH) following RSA with 135° humeral inclination and a neutral glenosphere without lateralization for PHFs. METHODS: In this retrospective case series, all patients with an acute PHF treated with primary RSA with 135° humeral inclination and a standard glenosphere without lateralization during a four-year period were followed up. Constant score (CS), patient satisfaction (subjective shoulder value (SSV)), TH and glenoid notching were analyzed. RESULTS: 38 patients with a mean age of 77 ± 8 years were available for follow-up at 34 ± 5 months. The mean adjusted CS was 61 ± 9 points. TH of the greater tuberosity (GT) was 82% and resulted in significantly improved abduction (117° vs. 81°; P < 0.001), forward flexion (139° vs. 99°; p < 0.001), external rotation (28° vs. 10°; p = 0.002), CS (65 vs. 41 points; p < 0.001) and patient satisfaction (SSV 79% vs. 48%; p < 0.001). TH of the LT was 87% without affecting internal rotation or overall outcome. The complication- and revision rate was 5%; implant survival was 100%. Scapular notching occurred in 3 (8%) cases (all grade 1). CONCLUSION: RSA with 135° humeral inclination and a standard glenosphere for PHF leads to good functional outcome in combination with a high rate of TH and a low rate of scapular notching. The short-term revision rate is low and the results are predictable and continuous. TH is associated with improved ROM, patient satisfaction and functional outcome.