抄録
Objective: We radiologically examined changes in spine and lower extremity alignments in patients after they underwent total hip arthroplasty with shortening osteotomy for high dislocation of the hip.
Methods: The present study involved eight hip joints in seven patients (six women and one man). The Crowe classification was type III in two hip joints and type IV in six hip joints. The mean age of the patients at the time of operation was 59.1 years, and the mean follow-up period was 1 year and 9 months.
Results: The mean leg length discrepancy decreased from 4.4 cm before surgery to 1.8 cm after surgery. The mean Japanese Orthopaedic Association score improved from 48.4 points before operation to 78.8 points at the final observation. The femorotibial angle of the operated sides improved from a mean valgus angle of 167.6° before surgery to 172.3° after surgery. Lateral pelvic tilt improved from a preoperative mean angle of 12.5° to a postoperative mean angle of 7.9°. Lumbar spinal curvature decreased from a mean Cobb angle of 20.0° before surgery to 15.1° and after surgery. Pain of the low back and knee joint showed improvement with these alignment changes.
Conclusion: Some patients with marked leg length discrepancies had pelvic tilt and secondary low back pain and knee joint pain, but reconstruction of the hip joint in the primary acetabulum with osteotomy was effective for improving not only the leg length discrepancy but also the lumbar and knee joint alignments.
