Total hip arthroplasty for avascular necrosis and degenerative osteoarthritis of the hip.

Although several studies of various treatment modalities have been reported during the past decade, osteonecrosis of the femoral head remains a difficult therapeutic problem. Total hip replacement which is reserved for patients showing collapse of the femoral head, usually shows poorer results in patients with osteonecrosis compared with those with osteoarthritis. Uncemented total hip arthroplasty was performed on 29 patients with avascular necrosis of the femoral head and 29 patients with degenerative osteoarthritis. After a mean followup of 7.6 years and 7.1 years for the two groups of patients, only one failure was observed in one patient with osteonecrosis. Clinical evaluation after cementless total hip arthroplasty in both groups of patients revealed improvement in all parameters. Postoperatively, pain improved from 1.4 to 5.1, walking ability from 3.4 to 5.3, and range of motion from 4.5 to 5.5 in patients with osteonecrosis, and pain improved from 1.2 to 5.3, walking ability from 3.2 to 5.4, and range of motion from 3.1 to 4.7 in patients with osteoarthritis. Thigh pain was observed postoperatively in only two and three patients treated for osteonecrosis and osteoarthritis, respectively. The present results using cementless arthroplasty seem to be somewhat better than those reported for cemented arthroplasty in patients suffering from osteonecrosis. The clinical and radiographic findings after noncemented arthroplasty in patients with osteonecrosis of the femoral head and in patients with degenerative arthritis of the hip were similar in the two groups.