The purpose of this study was to review the outcome of patients with osteonecrosis of the humeral head, based on etiology and treatment with either hemiarthroplasty or total shoulder arthroplasty (TSA). Sixty-four shoulders, with an average age of 57 years, were evaluated at a mean of 4.8 years. Outcomes included L'Insalata and American Shoulder and Elbow Surgeons (ASES) scores, as well as range of motion (ROM). The overall ASES score was 67, average flexion was 127 degrees, and external rotation was 49 degrees. Outcomes did not differ based on etiology, but ROM was decreased with post-traumatic osteonecrosis. There was no difference in outcome or ROM between hemiarthroplasty and TSA. The complication rate was significantly higher with TSA (22%) than with hemiarthroplasty (8%). Achieving ROM in patients with post-traumatic osteonecrosis remains difficult. TSA was associated with a higher complication rate and decreased mobility and should be reserved for patients with stage V osteonecrosis.