抄録
In order to better understand the important factors related to successful long term (over 10 year) results following O'Malley's muscle release surgery, we evaluated X-ray findings before and after it. Until 1982 it was performed on 32 hips of 26 patients with osteoarthrosis. Twenty one of these patients (27 hips) were divided into 4 groups. Group 1 (9 hips) had had no pain for over 10 years. Group 2 (10 hips) had had almost no pain for more than 6 years following surgery and still had less pain than before surgery. In Group 3a (4 hips), pain did not decrease, and THA was performed within 5 years of the surgery. In Group 3b (4 hips), pain decreased during the early years, but then recurred, and THA was performed more than 5 years after surgery.
The joint space, Sharp angle, acetabular head index (AHI), modified acetabular depth, and length of roof osteophyte were measured from X-ray films taken prior to surgery, and 1 and 3 months, and 1 and 3 years following surgery. The factor most closely related to successful results was joint space. In Groups 1 and 2, the joint space had definitely enlarged 3 months after surgery. In contrast, the joint space remained narrow in all of the Group 3a cases. The Sharp angle and AHI were not different among the 4 groups. In Group 3a, no roof osteophytes were found and modified acetabular depths were less than those in the other groups.
