Kenji Utsunomiya

Use of bipolar hip arthroplasty in states of acetabular deficiency

Bipolar hip arthroplasty was performed on 557 hips from December 1980 to June 1988. The clinical results and serial roentgenograms of 37 hips with acetabular deficiency, treated by arthroplasty from December 1980 to June 1983, were followed for a minimum of five years. The longest follow-up period was seven years and six months after the operation. The clinical score was assessed by the hip rating score of the Japanese Orthopaedic Association, which assigns a maximum of 100 points. The preoperative clinical score ranged from 24 to 56 points (mean, 42.2 points). The postoperative score improved to a range of 71–100 points (mean, 82.7 points). Of 37 hips examined, 31 hips were pain-free. As measured from the serial roentgenograms after the operation, the overall distance of central migration of the prosthesis in 37 hips was 0–5 mm, with an average of 1.4 mm, two years after the operation. At the five-year follow-up evaluation, 27 of 37 hips showed no additional central migration. The overall distance of superior migration of the prosthesis in 37 hips was from 0 to 8 mm, with an average of 2.6 mm, two years after the operation. Additional superior migration was noticed in 18 of 37 hips (48.6%) at the time of this five-year follow-up evaluation.

Bipolar hip arthroplasty in rheumatoid arthritis.

Bipolar hip arthroplasty with bone grafting was performed on 25 joints with rheumatoid arthritis from 1981 to 1985. The results and roentgenographical progress of the grafted bone were followed for a minimum of two years, the longest follow-up examination occurring six years after the operation. The clinical score was assessed by the hip rating score of the Japanese Orthopaedic Association, which assigns a maximum of 100 points. The preoperative clinical score ranged from 22 to 59 points (mean, 42.6). The postoperative score improved to a range of 65-92 points (mean, 72.8). Of 24 hips examined, 21 (87.5%) were painless. As measured serially from the roentgenograms made immediately after the operation, the overall distance of central migration in 24 hips was 0-8.5 mm (average, 2.7 mm). The overall distance of superior migration in 24 hips was 0-10 mm (average, 3.7 mm). A single massive bone graft using extracted femoral head was considered to be better than bone fragments as the procedure for acetabular reconstruction during bipolar hip arthroplasty in rheumatoid arthritis.

Surgical Treatments for Lumbar Spinal Canal Stenosis

Low back pain accompanied with degenerative lumbar spine is an important problem as well as cauda equina syndrome for lumbar spinal canal stenosis. The purpose of the surgical intervention is to decompress the neural stractures without spoiling stability of the lumbar spine. In point of this purpose, Wedges osteotomy is one of the ideal methods for laminectomy. Multiple fenestration at the narrow interlaminar segments is a new method.We treated nineteen cases of the lumbar spinal canal stenosis surgically from 1982 o 1986 in our hospital. Central laminectomy was done in one case, Modified Wedges osteotomy in eleven cases, multiple fenestration in five cases, anterior interbody fusion in two cases. Posterior spinal fusion was done in three cases of laminectomy, and in all cases of multiple fenestration. Harrignton distraction rod was employed in two cases, Harrignton compression rod in one case, and L-type rod in two cases.Good results were obtained concerning involvement of the cauda equina. But one case accompanied with cervical spondylotic myelopathy and one case with thoracic spinal cord tumor developed left paraparesis as sequelae due to spinal cord involvement. Low back pain was deteriorated postoperatively in two cases of laminectomy without fusion.One was a case of degenerative spondylolisthesis. In another one, postoperative stress ulcar occurred and long period of rest in bed was required.Instrumentation gave stability to the spinal column immediately after surgery and was able to make postoperative care easy.