Isao Asayama

Total hip arthroplasty: the relationship between posterolateral reconstruction, abductor muscle strength, and femoral offset.

Purpose. To evaluate the relationship between posterolateral reconstruction, abductor muscle strength, and femoral offset following total hip arthroplasty. Methods. Of 28 patients (56 limbs) we assessed, 12 underwent posterolateral reconstruction (reconstruction group) and 16 did not (non-reconstruction group). Isometric abductor muscle strength was measured with a handheld dynamometer. Each patients muscle strength was converted into a force to body weight ratio, and this ratio was used in the comparisons. Results. The reconstruction group showed a higher value in abductor muscle strength than the non-reconstruction group (p<0.05). Significant correlation between abductor muscle strength and femoral offset was found in the reconstruction group (p=0.016; r=0.674). Conclusion. Posterolateral reconstruction and appropriate reconstruction of femoral offset following total hip arthroplasty are important to improve the abductor muscle strength.

Intraoperative limb length measurement in total hip arthroplasty.

Abstract In order to evaluate the efficacy of intraoperative measurement of limb length inequality (LLI), we performed a prospective study on 64 patients who underwent unilateral total hip arthroplasty. The patients were divided into 2 groups. In Group I, the LLI was evaluated by the Shuck test, and in Group II by intraoperative measurement using a Steinman pin and an adjustable caliper. Preoperative LLIs assessed on radiographs averaged 1.18 cm in Group I and 0.37 cm in Group II.Résumé Pour évaluer l’efficacité de la mesure intra-opératoire de l’inégalité de la longueur d’un membre (ILM), nous avons effectué une étude prospective sur 42 patients qui ont subi une arthroplastie totale de la hanche unilatérale. Les patients furent divisés en 2 groupes selon la méthode particulière d’estimation intra-opératoire de ILM. ILM fut évalué par un essai de réduction dans le Groupe I et par une mesure intra-opératoire en utilisant une broche de Steinmann et un compas de calibrage ajustable dans le Groupe II. Sur les radiographies ILM intra-opératoires du Groupe I, la moyenne établie fut de 0,34 cm et pour le Groupe II de 0,41 cm. La moyenne établie de 1,15 cm dans le Groupe I et de 0,4 cm sur des radiographies ILM postopératoires a montré une différence significative entre les deux groupes.

Muscle strength improves after abductor-sparing periacetabular osteotomy.

We measured muscle strength after curved periacetabular osteotomy, one form of abductor-sparing periacetabular osteotomy, and then investigated the factors influencing postoperative muscle strength recovery. Curved periacetabular osteotomy was performed for acetabular dysplasia on 24 hips in 22 patients. All patients were females, with a mean age of 34.4 years. We based the severity of hip disease on the Tönnis classification. Isokinetic muscle strengths of the hips were measured preoperatively and 6 months and 12 months postoperatively. At 12 months postoperatively, the mean muscle strength (percentage difference to preoperative value) of the abductor was 42.2 Nm (129.6%), adductor 39.4 Nm (131.4%), flexor 48.4 Nm (121%), and extensor 45.8 Nm (130.5%), all of which exceeded the preoperative values. The 12-month postoperative muscle strength of patients with Grade 0 disease based on the Tönnis classification was greater in all directions than that of patients with Grades 1 and 2 disease. The preoperative stage was thought to be an essential factor in postoperative muscle strength recovery.Level of Evidence: Prognostic study, Level II (lesser quality prospective study-eg, patients enrolled at different points in their disease or < 80% followup). See the Guidelines for Authors a complete description of levels of evidence.

A quantitative anatomic characterization of the quadrilateral surface for periacetabular osteotomy

The periacetabular osteotomy described by Ganz et al is used widely, and includes an outward osteotomy from the quadrilateral surface. Because intraarticular extension of the osteotomy can complicate the Ganz osteotomy, it is important to image the margin of the hip. To prevent this complication, and to do this procedure more safely, 32 hemipelves from cadavers were used in the current study. Some landmarks were selected that can be clarified on the quadrilateral surface during the periacetabular osteotomy. The acetabulum was hollowed out using an acetabular reamer of the same size as each femoral head, and the margin of the penetrated hole through the acetabulum was determined using these landmarks. The posterior margin of the hip is located approximately 2 cm anterior to the sciatic notch. The anatomic guidepoint for the osteotomy of the ischium averaged 14 mm inferior to the distal margin of the hip. By clarifying the margin of the hip presumed on the quadrilateral surface in this way, the periacetabular osteotomy can be done more safely, without causing complications such as intraarticular chisel penetration.

Cementless Total Hip Arthroplasty Using an Autograft of the Femoral Head for Marked Acetabular Dysplasia: Case Series

Purpose. To assess the short-term outcome of cementless total hip arthroplasty involving an autograft of the femoral head in Japanese patients. Methods. Cementless total hip arthroplasty with autogenous bone block grafting was performed on 18 hips in 15 patients with marked acetabular dysplasia. The resected femoral head was used as a graft for the superior-lateral region of the true acetabulum. Clinical outcome was correlated with the placement of the acetabular component, as revealed in radiographs. Results. The 13 women and 2 men had a mean age of 60.2 years (range, 37.0–73.0 years) at primary surgery and a mean follow-up duration of 3.3 years (range, 2.0–5.3 years). According to the classification of Crowe, 4 hips were in group I, 3 were in group II, one in group III, and 10 in group IV. The mean Harris Hip Score preoperatively was 45.7 (range, 19–69) and that at follow-up was 82.5 (range, 44–100). All 15 cases showed a good clinical outcome. There were no major intra-operative complications in this series. The grafted bones united in all patients. Two patients need surgical revision because the lateral insertion of the acetabular component resulted in loosening of it. Conclusion. Medial insertion of the acetabular component provides satisfactory short-term outcomes. Lateral insertion of the acetabular component during total hip arthroplasty should be avoided in patients with marked acetabular dysplasia.

Curved periacetabular osteotomy for the dysplastic hip: cadaveric and radiological analyses of safe procedures

Curved periacetabular osteotomy is a modified Ganzs procedure and requires an intrapelvic osteotomy. In order to establish the osteotomy line and the chisel inserting angles during the procedure, 32 cadavers and 28 three-dimensional computed tomographs were utilized. The guidepoints for the osteotomy line were obtained from the cadaveric analysis and the inserting angles of the chisel were measured from the radiological analysis. On the supra-acetabular portion, the C-shaped osteotomy line, starting from the proximal end of the anteroinferior iliac spine, should pass above the intersection point of the arcuate line and the line passing from the proximal end of the anteroinferior iliac spine to that of the ischial spine, and the chisel inserting angle should be 17° to the anterior surface of the ilium. On the quadrilateral surface, the C-shaped line should locate one finger width anterior to the greater sciatic notch, and the chisel inserting angle should be 25° to the quadrilateral surface. On the anterior aspect of the ischium, the chisel should advance with an inserting angle of 60° to the ground at the level of one finger width below the distal joint edge.

Durable Fixation With a Modern Fully Hydroxylapatite-Coated Long Stem in Complex Revision Total Hip Arthroplasty

We describe the use of a fully hydroxylapatite-coated long-stem femoral implant in a series of 40 complex revision total hip arthroplasties. All reconstructions involved severe bone loss or malalignment and were accomplished entirely without the use of augmentary bone graft. Outcomes were evaluated at 7 minimum years of follow-up (average, 10.2 years). Three stems were rerevised because of infection, trauma, and loosening with nonunion of a fracture. Bone ingrowth was radiographically evident by one postoperative year in all other cases. There were no cases of subsidence. Stress shielding with thigh pain was seen in one patient. The stem provided immediate stability and excellent long-term fixation in these reconstructions of severely diseased femurs.

Arthroscopic surgery for synovial chondromatosis of the hip: a report of two cases

AbstractWe have used arthroscopy in the treatment of synovial chondromatosis of the hip joint. Two patients complained of pain of the hip joint that was aggravated by weight bearing. On admission, range of motion of the affected hip joints was slightly restricted. At hip arthroscopy, osteochondral loose bodies were removed from the joint and partial synovectomy was performed. Histologic examination revealed synovial chondromatosis. Pain relief was obtained in both patients postoperatively.