Abstract
29 hips (follw-up rate: 44%) underwent hemiarthropathy for the treatment of osteonecrosis of the femoral head (ONFH). Bipolar hemiarthroplasty (Kyocera Physiohip type) was carried out for all the patients. The average age at operation was 47 years old (24-65), and the mean follow-up interval was 6.4 years (2.8-10.9). 1 was at stage 2, 14 at stage 4 at operation. 4 hips receired a second operation due to the failure of rotational osteotomy, and 1 was unknown. The JOA score was evaluated. The pain, ROM, walk and ADL scores were 35 (20-40), 17 (13-20), 13 (5-20), and 16 (820) respectively. The mean total score was 81 (65-100). Femoral head migration was observed in 7 hips (29%). The distance of migration of most hips was within 5mm. 1 hip which had acetabular reaming at operation showed central migration. There was a tendency for migration in most hips at stage 4 at operation. This study showed that bipolar heimarthroplastyis a promising treatment for ONFH hip although further evaluation is required.
