Osteonecrosis of the humeral head: Relationship of disease stage, extent, and cause to natural history

One hundred fifty-one patients with 200 shoulders affected with osteonecros is of the humeral head were evaluated For associated factors, the need for prosthetic replacement surgery, the state of the unoperated shoulder, and t he existence of prognostic factors. Associated Factors included corticoster oid use in 112 shoulders, trauma in 37, Gaucher's disease in 3, sickle cell disease in 3, and radiation necrosis in 1. No cause was evident in 44 shou lders. Ninety-seven shoulders had replacement surgery The need for replacem ent surgery was found to be related to extent and stage of humeral head inv olvement and to diagnosis. Shoulders with a traumatic cause of osteonecrosi s required surgery more often (cumulative rate of 77.8% by 3 years). Advanc ing stage of disease was also related to the need For surgery. By 3 years t he cumulative replacement rate was performed in 42% for shoulders with stag e 2 disease, 29% with stage 3 disease, 55% with stage 4 disease, and 79% wi th stage 5 disease. In a similar manner, surgical frequency increased with increasing extent of humeral head involvement. In 60 shoulders not surgical ly treated that were monitored an average of 8.6 years (range 3.4 to 14.5 y ears), there was none to occasional moderate pain in 46 and moderate to sev ere pain in 14. The mean American Shoulder and Elbow Surgeons score was 64. 8.