To determine the effects of sickle cell disease on the glenohumeral joint, 28 shoulders in 14 patients with SS sickle cell hemoglobinopathy were studied clinically and roentgenographically. patients were randomly selected; their mean age was 46 years (range, 22 to 63 years). Pain, stability, and function of the shoulders were assessed, and roentgenograms were evaluated for osteonecrosis. All 28 shoulders had some degree of pain with activity, but functional range of motion was maintained despite symptoms. Seventy-one percent of the patients had had total hip arthroplasty and 21% had had total knee arthroplasty for osteonecrosis; there was a mean of 1.5 previous joint implants per patient. Our study results show that, in patients with sickle cell hemoglobinopathy, symptoms of humeral head osteonecrosis are better tolerated than those of osteonecrosis in the lower extremities, delaying the need for surgical intervention. With severe pain and functional limitations, shoulder arthroplasty is the procedure of choice in this patient population. However, the risks are greater for patients with sickle cell disease than for other patients who have humeral head osteonecrosis, and thorough preoperative medical and anesthesia evaluations are necessary. These patients require perioperative transfusion or plasmapheresis and sufficient intraoperative hydration and oxygenation to avoid precipitating a sickle cell crisis; in addition, use of methyl methacrylate should be avoided.