Shoulder arthroplasty in cases with avascular necrosis of the humeral head.

Avascular necrosis (AVN) is a relatively uncommon cause of glenohumeral arthritis. Previous retrospective reviews of shoulder arthroplasty for AVN have shown very good results in small numbers of patients. This study prospectively evaluated a consecutive series of 21 shoulders in 19 patients treated with the same modular prosthesis at a single institution. Of the shoulders, 8 developed AVN after a proximal humeral fracture, 1 was associated with a massive rotator cuff tear, 10 developed after corticosteroid therapy, and 2 were idiopathic. The patients, 14 women and 5 men, with a mean age of 54 years, were followed up for a mean of 4.7 years (range, 2 to 8 years). Hemiarthroplasty was performed in 15 shoulders, whereas 6 required total shoulder arthroplasty. Assessment included visual analog scales, the Simple Shoulder Test, and the American Shoulder and Elbow Surgeons Shoulder Score Index (SSI). Physical examination was performed, and radiographs were obtained. The visual analog scale scores for pain and function improved significantly after surgery (P < .01). The mean SSI score rose from 36 to 81 (where 0 indicates the worst outcome and 100 indicates the best outcome). The mean number of positive responses on the Simple Shoulder Test increased from 3 to 10. Mean active elevation increased from 88 degrees to 123 degrees . External rotation improved from 7 degrees to 34 degrees , and internal rotation improved from L4 to T12. No difference in outcome was noted based on age or sex. Patients with steroid-related or idiopathic AVN had greater pain and functional impairment preoperatively (mean SSI score, 26) than those with prior fracture or rotator cuff tear (mean SSI score, 49) (P < .01). Postoperatively, however, these groups fared equally well (mean SSI score, 78 vs 82). Shoulder arthroplasty for AVN produces good pain relief and function, although a concurrent series with osteoarthritis yielded better results. Forward elevation did not approach normal as had been previously reported.