Yuichiro Akiyoshi

Curved periacetabular osteotomy for treatment of dysplastic hip.

The Bernese periacetabular osteotomy has a considerable rate of postoperative complications such as reflex sympathetic dystrophy, motor nerve palsy, heterotopic ossification, and delayed union of the ilium, which are assumed to be caused by extensive exposure or asphericity of the osteotomy surfaces. To address these issues, we developed the curved periacetabular osteotomy, a modification of the Bernese periacetabular osteotomy which limits dissection, prevents the outside of the ilium from being exposed, and produces osteotomy surfaces with the same curvature. Curved periacetabular osteotomies were done on 128 hips in 118 patients whose average age at the time of surgery was 35.2 years (range, 16–59 years). The average followup was 46 months (range, 24–99 months). The average center-edge angles were 4° (range, −15°–5°) preoperatively and 35° (20°–55°) postoperatively, and union of the iliac osteotomy was achieved in all hips. We experienced three asymptomatic pubic nonunions. Dysesthesias occurred in 27 patients along the lateral femoral cutaneous nerve and symptoms resolved in 23 patients within 1 year. The average Harris hip score improved from 72 to 93 points. There were no major complications such as sciatic nerve palsy, abductor dysfunction, or heterotopic ossification. Level of Evidence: Therapeutic study, Level IV (case series—no, or historical control group). See the Guidelines for Authors for a complete description of levels of evidence.

Acetabular cysts heal after successful periacetabular osteotomy

The presence of subchondral bone cysts reflects degeneration or defects of the articular cartilage and elevated local stresses in the subchondral bone. We asked whether the presence of acetabular cysts deleteriously influenced the clinical and radiographic results of periacetabular osteotomy for treatment of dysplastic hips. We retrospectively reviewed 46 hips in 43 patients with cartilage narrowing who had periacetabular osteotomies. Of the 46 hips, 21 had acetabular cysts (cyst group) and 25 did not (control group). The average followups were 5.8 and 5.4 years in the cyst and control groups, respectively. We compared the Harris hip score and coverage of the femoral head between the two groups. The clinical results were similar between the two groups. There were no differences in radiographic evaluations between the two groups at the latest followup. In the cyst group, complete or partial healing of the cysts was observed in 17 of the 21 hips. A postoperative increase in the center-edge angle of 20° or greater was found in 14 of the 17 hips. The preoperative presence of acetabular cysts did not influence the results of periacetabular osteotomy. Adequate rotation of the acetabular fragment induced cyst remodeling.Level of Evidence: Level III, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Partial physeal growth arrest treated by bridge resection and artificial dura substitute interposition.

We treated four cases of partial physeal growth arrest by resecting the bone bridge and interposing an expanded polytetrafluoroethylene membrane, which has minimal tissue response. We evaluated three cases with sufficiently long follow-up. No apparent recurrence of the bone bridge and no limb length discrepancy occurred in any of the cases. No remodeling after the operation occurred. In one case, which underwent this operation and corrective osteotomy of the proximal tibia, slight recurrence of the varus deformity occurred which was detected only by radiographs, and did not compromise the alignment of the leg. There were no complications.

Blood flow of the gluteus medius muscle: An animal study

Abstract We investigated the effects of subperiosteal dissection on blood flow in the gluteal medius muscle in adult rabbits using the hydrogen washout technique. After the control blood-flow rate was determined, 8 rabbits were separated into 2 groups according to the direction of the dissection. The gluteal medius muscle was dissected from the iliac crest in the proximal-distal direction in 10 hips. In another 6 hips, the greater trochanter was osteomised and the gluteus medius muscle was dissected from the ilium in the distal-proximal direction. Dissection of the middle third of the gluteus medius muscle caused the most significant reduction in blood flow, more than 50% in both groups. This result indicates that minimising damage to the mid-portion of the gluteus medius muscle is important for reducing the incidence of post-operative complications.Résumé Nous avons examiné et étudié les effets de la dissection sous-périostale de l’écoulement sanguin dans les muscles médians fessiers de lapins adultes en utilisant la technique de lavage total à l’hydrogéne. Aprés le contrôle de la proportion de l’écoulement sanguin, les lapins furent séparés en deux groupes selon l’objectif de la dissection. Dans le premier groupe, les muscles médians fessiers furent disséqués dans 10 hanches à partir de la crête iliaque dans la direction proximale-distale. Dans le second groupe de 6 autres hanches, le grand trochanteur fut ostéotomisé, et le muscle moyen fessier fut disséquéà partir de l’ilium dans la direction distale-proximale. La dissection du tiers intermédiaire du muscle moyen fessier a provoqué la diminution la plus significative dans l’écoulement sanguin, soit plus de 50% pour les deux groupes. Ce résultat indique qu’une minimisation des lésions à la partie médiane du muscle moyen fessier est importante pour la réduction des complications post-opératoires.