抄録
We report here the results of a follow-up study for more than 3 years postsurgically on 67 cases (80 joints) of bipolar hip arthroplasty to determine indications for and limitations of the use of bipolar endoprostheses for the treatment of osteoarthritis (OA) of the hip.
Radiological evaluation demonstrated that the rate of migration of the outer head was high (84.6%) in OA patients, particularly in cases whose acetabulum was reconstructed with grafted bone; patients with severe dysplasia of the acetabulum tended to have upward and outward migration. Among patients for whom the shortest distance between the medial wall of the ilium and the outer head was less than 5mm, the rate of migration of the outer head was also high (83.3%) .
Migration was rarely observed in patients whose CE angle was greater than 30 degrees after reaming. We therefore conclude that bipolar hip arthroplasty for the treatment of OA is indicated only for patients with mild dysplasia.