Takashi Hisatome

The state of the articular cartilage at the time of surgery as an indication for rotational acetabular osteotomy

We have studied whether the state of the articular cartilage at the time of rotational acetabular osteotomy for dysplasia of the hip affects the outcome 2 to 5.5 years after surgery. Arthroscopy in 57 patients (59 joints) at the time of the operation showed grade-0 changes in seven, grade-1 in nine, grade-2 in 17, grade-3 in 14 and grade-4 in 12 joints, according to the classification of Outerbridge. There was radiological evidence of the progression of arthritis in four joints which were classified at arthroscopy as grade 4. Stepwise regression analysis showed that damage to acetabular or femoral articular cartilage significantly affected the progression of arthritis. We conclude that the short-term results of successful rotational acetabular osteotomy for dysplasia are affected by the state of the articular cartilage.

Significant effect of the posterior tibial slope on the weight-bearing, midflexion in vivo kinematics after cruciate-retaining total knee arthroplasty.

The purpose of the present study was to compare weight bearing (WB) and non-WB conditions, and to evaluate the effect of the posterior tibial slope (PTS) on the in vivo kinematics of 21 knees after posterior cruciate ligament-retaining total knee arthroplasty during midflexion using 2-dimensional/3-dimensional registration. During WB, medial pivot and bicondylar rollback were observed. During non-WB, both the medial and lateral condyles moved significantly more anteriorly as compared to the WB state. These patients were divided into 2 groups according to their PTS. The large PTS group showed a significant posterior displacement of the medial femoral condyle as compared with the small PTS group, but no significant difference was observed at the lateral femoral condyle during both WB and non-WB. The PTS influenced knee kinematics through gravity (124/125).

Hidden intrapelvic granulomatous lesions associated with total hip arthroplasty: a report of two cases.

Granulomatous lesions have been reported in association with total hip arthroplasties both with and without cement 1-9. The chief cause of these lesions is considered to be osteolysis induced by polyethylene wear debris from the hip prosthesis 7,9,10. We report on two patients with a hidden intrapelvic granulomatous lesion associated with a total hip arthroplasty. Both patients were informed that data concerning their cases would be submitted for publication. Previous reports identified intrapelvic granulomas only after symptoms developed as a result of compression of vital structures. The granulomatous lesions in this report were confirmed by computed tomography but were not detected by plain radiography. Case 1. In 1984, a forty-six-year-old woman with the diagnosis of osteoarthritis secondary to dysplasia of the right hip joint underwent a Charnley total hip arthroplasty with cement. The postoperative course was uneventful. During the twelfth postoperative year, the right hip joint gradually became painful. Sixteen years postoperatively, extensive polyethylene wear of the acetabular component was noted ( Fig. 1 ). Fig. 1: Radiograph of the right hip of a sixty-two-year-old woman, made before revision at sixteen years and four months following a Charnley total hip arthroplasty with cement. Extensive polyethylene wear of the acetabular component is present. In 2001, the patient underwent revision of the acetabular cup. The revision cup was …

Efficacy of bone marrow mononuclear cells to promote bone regeneration compared with isolated CD34+ cells from the same volume of aspirate

Autologous bone marrow mononuclear cell (BMMNC) transplantation is currently an emerging clinical treatment in the orthopedic as well as cardiovascular fields. It is believed that the therapeutic effect of the BMMNCs is due to neovascularization enhanced by the CD34(+) cells contained therein, which include endothelial progenitor cells. However, isolation of the CD34(+) cell fraction for clinical application has many disadvantages such as cost and invasiveness related to cell mobilization with cytokine. To investigate whether a purification step is in fact necessary for bone regeneration, we separated BMMNCs, CD34(+), and CD34(-) cells from the same initial volume of rabbit bone marrow aspirates. We then transplanted them back into a femoral bone defect of the same rabbit together with atelocollagen gel and basic fibroblast growth factor (bFGF) and evaluated neovascularization and bone regeneration up to 8 weeks after transplantation. The greatest potential for neovascularization and bone regeneration medicated by cells from the same volume of bone marrow aspirate was found in the BMMNC group. Although purified CD34(+) cells might be an ideal cell source, BMMNCs could be a practical and feasible cell source for bone regeneration in present clinical settings with limited cost, availability of materials, and technical issues for transplantation.

Second- and third-generation omniflex modular femoral stem

Primary cementless total hip arthroplasty (THA) using the Omniflex modular femoral stem was conducted on 73 hips in 70 patients. The arc deposition (AD)-type stem was used in 26 hips, and the hydroxyapatite (HA)-type stem was used in 47 hips. The mean follow-up period of patients in the AD group was 78 (range, 61-96) months and that of patients in the HA group was 52 (range, 36-61) months. Clinically, improvement in the Harris hip score occurred in all cases. Thigh pain was reported in 3 (11.5%) AD hips and in 1 (2.1%) HA hip. Radiologically, bone ingrowth fixation was seen in 88.5% of the AD group and in 97.9% of the HA group. No subtrochanteric stress shielding, stem migration of > 2 mm, or revision THA occurred. The second- and third- generation Omniflex stems are useful cementless devices resulting in favorable initial biologic fixation and little bone atrophy at mid-term follow-up.

Spontaneous decrease in focal osteolysis in the unrevised femur after revision of a contralateral bipolar hemiarthroplasty: a case report.

Periprosthetic osteolysis can result in aseptic loosening of components and massive bone loss 1-4. To our knowledge, there have been few reported cases of spontaneous decreases in osteolysis 5. We report on a patient who had a spontaneous decrease in osteolysis in the unrevised femur after revision of a contralateral hip arthroplasty. A thirty-five-year-old man who had undergone a bilateral bipolar hemiarthroplasty six years earlier at another institution presented to our hospital because of bilateral thigh pain. In 1990, the patient had undergone transplantation of a cadaveric kidney in response to chronic renal failure attributable to nephrotic syndrome. Following renal transplantation, oral administration of prednisolone, cyclosporine, azathioprine, and mizoribine had been initiated and had continued uninterrupted. In 1991, the patient experienced bilateral hip pain and was examined at another institution, where a diagnosis of steroid-induced osteonecrosis of the femoral head was made. In 1992, he underwent bilateral bipolar hemiarthroplasty (Omniflex microstructured femoral component; Stryker, Allendale, New Jersey). In 1995, he began to experience left thigh pain and, subsequently, right thigh pain while walking. In August 1998, he was examined at our hospital. At the initial examination, the patient was …