The results of the analysis of rapid destruction of 7 hip joints in 5 rheumatoid patients, 1 male and 4 females, are reported. In 4 patients, activities of rheumatoid arthritis were remarkable when the destruction occurred. Corticosteroid was used in all these patients. X-ray films showed 3 patterns of destruction: 1) 3 hips showed absorption of the femoral heads and protorusio acetabuli; 2) 2 hips showed absorption or flattening of femoral heads and acetabular destruction upward or upward on the lateral part of the joint; 3) 2 hips showed rapid developing of cystic shadow on x-ray film followed by crushing of the weight bearing area of the femoral head. Pathological findings of hip joint synovium showed active synovitis with bone fragment and multinuclear giant cells. Using bone morphometry technique, the femoral head showed a high turnover of bone while the iliac bone showed a low turnover.
