Outcomes of primary reverse shoulder arthroplasty in patients with morbid obesity

BackgroundObesity 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.MethodsWe reviewed all primary RSAs performed on morbidly obese (body mass index [BMI] ≥40 kg/m2) 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/m2, and the mean age was 67.7 years.ResultsThe 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).ConclusionsRSA is a successful procedure in morbidly obese patients (BMI ≥40 kg/m2). At intermediate follow-up, there is good implant survival with a reasonable complication rate and excellent pain relief.