Outcomes of primary reverse shoulder arthroplasty in patients with morbid obesity.

BACKGROUND: Obesity is a risk factor for worse outcomes in anatomic shoulder arthroplasty. The purpose of this investigation was to determine outcomes of primary reverse shoulder arthroplasty (RSA) in patients with morbid obesity.

METHODS: We reviewed all primary RSAs performed on morbidly obese (body mass index [BMI] ≥40 kg/m(2)) patients from 2005 to 2012 at our institution with at least 2 years of follow-up. The study included 41 patients (57% female), the mean BMI was 44 kg/m(2), and the mean age was 67.7 years.

RESULTS: The only intraoperative complication was an inferior glenoid fracture that remained stable after glenosphere implantation. At a mean follow-up of 3.2 years (range 2-7.36 years), 2 patients (5%) required revision surgery for infection (n = 1) and humeral loosening (n = 1). Survival was 98% at 2 years and 92% at 5 years. Additional postoperative complications included ulnar neuropathy (n = 1) and heterotopic ossification (n = 2). Pain relief was excellent, with 93% reporting moderate or severe pain preoperatively compared with 2% postoperatively (P < .001). Shoulder abduction improved from 49° to 142° and external rotation from 17° to 50° (P < .001). The average American Shoulder and Elbow Surgeons score was 71.1. At the most recent follow-up, no patients had glenoid lucency, 1 (2%) had humeral lucency, and 2 (5%) had inferior scapular notching. Laborers had higher risk for revision surgery (P = .01), and females had worse functional outcomes and shoulder motion (P < .02).

CONCLUSIONS: RSA is a successful procedure in morbidly obese patients (BMI ≥40 kg/m(2)). At intermediate follow-up, there is good implant survival with a reasonable complication rate and excellent pain relief.