Seiki Iwasada

Twenty years' followup of intertrochanteric osteotomy for treatment of the dysplastic hip

A followup study of more than 15 years of intertrochanteric osteotomy for osteoarthrosis of the dysplastic hip was performed in 52 hips of 42 patients with varus osteotomy and in 58 hips of 53 patients with valgus osteotomy. Varus osteotomy was indicated for predegenerative or early degenerative stages of osteoarthrosis, and valgus osteotomy was indicated for progressive or end stage disease. The average age at time of varus and valgus osteotomies was 25 and 37 years, respectively, and the average followup period was 21 and 20 years, respectively. Using Kaplan-Meiers method (end point, Harris Hip Score < 70 points or salvage operation), the 10- and 15-year survival rates for varus osteotomy were 89% and 87% and for valgus osteotomy were 66% and 38%, respectively. Radiographic measurements of the postoperative acetabular head index and center edge angle in varus osteotomy were better in the group with good results than those in the group with poor results. There were no differences in radiographic measurements between the group with good results and the group with poor results of valgus osteotomy. Intertrochanteric varus and valgus osteotomy delayed the need for total hip arthroplasty in young patients with osteoarthrosis of the dysplastic hip.

Pedicle bone grafting versus transtrochanteric rotational osteotomy for avascular necrosis of the femoral head

Segmental collapse occurs in the early stage of avascular necrosis (AVN) of the femoral head, and is associated with a poor prognosis. Since it develops at a relatively young age, the long-term outcome after total hip replacement is a major concern. We have compared the long-term results of pedicle bone grafting (PBG) with those of transtrochanteric rotational osteotomy (TRO). In the PBG group there were 23 men (27 hips) and three women (4 hips) with a mean age at the time of surgery of 38 years and a mean follow-up of 13 years. In the TRO group there were 44 men (55 hips) and 19 women (22 hips) with a mean age at the time of surgery of 39 years and a mean follow-up of seven years. Failure was defined as a need for total hip replacement or a Harris hip score below 70. The long-term results were similar for the two groups. The survival rates at five and ten years were 85% and 67%, respectively, in the PBG group, and 71% and 61%, respectively, in the TRO group, according to Kaplan-Meier survivorship analysis. In the TRO group patients in stage II had significantly better results that those in stage III.

Vascularized pedicle bone-grafting for nontraumatic avascular necrosis of the femoral head : A 5- to 11-year follow-up

We investigated the results of 31 hips in 26 patients with nontraumtic (n = 20) and steroid-induced (n = 6) avascular necrosis of the femoral head (ANFH) treated with vascularized iliac pedicle bone graft (PBG). The average age at operation was 38.3 years. Three were women and 23 men. The average follow-up was 8.0 years. The Harris hip score prior to operation and at latest follow-up improved from 62 to 83; one hip collapsed and was revised with a bipolar endoprosthesis. At the final follow-up, 19 hips (63%) were clinically rated as good to excellent, 4 fair, and 7 poor. At the final follow-up, 15 of 27 hips (56%) of stage II before operation showed progressive collapse after bone grafting. In steroid-induced ANFH, in three women, 2 of 4 hips showed poor results. These results are only slightly better than those of core decompression and no better than those obtained after decompression and simple nonvascularized grafts to provide support for the subchondral bone. We concluded that vascularized PBG is sometimes indicated for ANFH in an early stage before collapse of the femoral head.

Osteonecrosis of the femoral head associated with pregnancy

Abstract A 31-year-old pregnant woman suddenly complained of bilateral hip pain 2 weeks before delivery. She was delivered of triplets by Caesarean section. She had been treated with human menopausal gonadotropin and human chorionic gonadotropin (hMG-hCG) before pregnancy. Radiograms of the hip joint showed collapse of the femoral heads bilaterally. Magnetic resonance imaging revealed a band pattern of low signal intensity for both hips on T1- and T2-weighted images. She had no history of steroid therapy or alcohol abuse. Osteonecrosis of the femoral heads bilaterally associated with pregnancy was confirmed. Pathology of the femoral head showed typical empty lacunae and necrosis of the trabecula.

Prediction of osteonecrosis by magnetic resonance imaging after femoral neck fractures.

Thirty-one patients undergoing internal fixation for femoral neck fractures who were examined by magnetic resonance imaging at 2, 6, and 12 months after surgery and who could be followed up more than 2 years were enrolled in the current study. The items investigated were timing of the appearance of the band image on T1 weighted images, magnetic resonance imaging classification, and plain radiographs. Band images were observed 2 months after surgery in eight patients and 6 months in 12 patients (39% of all patients). According to the location and extent of the band image on magnetic resonance imaging, one patient was classified in the B1 Group (lateral type), four patients in the B2 Group (surface type), three patients in the B3 Group (intermediate type), and four patients in the B4 Group (extended type). Band images appeared in all patients in the B4 Group 6 months after surgery. Femoral heads of the patients in the B3 and B4 Groups by magnetic resonance imaging classification all were collapsed. On plain radiographs, osteonecrosis of the femoral head could be diagnosed in eight patients between 11 and 24 months after injury. The interval giving the greatest sensitivity, specificity, and accuracy of the diagnosis of osteonecrosis of the femoral head by magnetic resonance imaging was 6 months after surgery.

Total hip arthroplasty after failed intertrochanteric valgus osteotomy for advanced osteoarthrosis

Thirty hips that had undergone conversion total hip arthroplasty because of failed intertrochanteric valgus osteotomy for advanced osteoarthrosis were analyzed clinically and radiographically for more than 2 years. The average followup after total hip arthroplasty was 7 years (range, 2-18 years). The average age of the patients at the time of valgus osteotomy was 42 years (range, 30-63 years). The average age of the patients at the time of conversion total hip arthroplasty was 57 years (range, 43-76 years), and the average period between valgus osteotomy and conversion was 14 years (range, 3-24 years). Perioperative complications in conversion total hip arthroplasties were minimal, and intramedullary reaming was performed easily. Of the 30 conversion total hip arthroplasties, 12 cemented and 18 cementless components were used, respectively. Kaplan-Meiers survival analysis indicated that survivorship of cemented stems was significantly higher than that of conventional cementless stems. Cemented stems are preferable for conversion total hip arthroplasty after failed femoral valgus osteotomy.

Transtrochanteric rotational osteotomy for osteonecrosis of the femoral head

We reviewed 48 hips in 43 patients 3–7.1 years (average 4.6 years) after Sugioka transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. The average age at operation was 41 years. Thirty-four patients were men and 9 women. Overall results at the final follow-up were satisfactory in 30 hips (62%). Kaplan-Meiers survivorship was 62% at 3 years and 60% at 5 years postoperatively. Six hips for which the ratio of the intact area of the articular surface on the preoperative lateral radiograph was less than 30% showed further collapse. Five hips were converted to bipolar hemiarthroplasties or total hip arthroplasties. Complications, such as varus deformity, subtrochanteric fracture, and ectopic bone formation, occurred in eight hips. Five of them were operated on in the first 2 years of this series. Three of these five operations had unsatisfactory results. We conclude that satisfactory results can be achieved using this osteotomy by maintaining exact surgical technique and by limiting the surgical indications to hips with an intact area of more than one-third of the entire articular surface on the lateral radiograph of the femoral head.

Catastrophic Failure of Cementless Total Hip Arthroplasty Using a Femoral Component Without Surface Coating

Consecutive series of 90 hips that had had a primary cementless arthroplasty with use of straight collarless stems between January 1988 and September 1992 were reviewed. Twenty-eight hips with Omnifit Normalized Stems (Fit-N) and 45 hips with Omniflex Normalized Stems (Flex-N) without porous coatings were compared clinically and radiographically with 17 hips with Omnifit Microstructured Stems (Fit-M) with porous coating. The average follow-up periods for the 3 stems were 97 months, 73 months, and 93 months. Revision was performed or awaited in 9 cases (32.1%) in the Fit-N group, 18 cases (40.0%) in the Flex-N group, and 1 case (5.8%) in the Fit-M group. The average annual subsidence was 0.62 mm/y, 0.73 mm/y, and 0.17 mm/y. Osteolysis of more than 3 mm occurred in 28.6%, 37.8%, and 23.5%. Fit-N stems and Flex-N stems without porous coatings are not appropriate for cementless total hip arthroplasty.

Bone scintigraphy and magnetic resonance imaging after transtrochanteric rotational osteotomy.

Abstract Objective. To assess the ability of bone scintigraphy and magnetic resonance imaging (MRI) to predict the outcome of transtrochanteric rotational osteotomy (TRO) for osteonecrosis of the femoral head (ONFH). Design. This study was a prospective evaluation of imaging techniques. Patients and methods. MRI and bone scintigraphy were performed on 20 hips in 18 patients at 3 months after TRO. The radiographic findings at 3 months after TRO, and the MRI and bone scintigraphic findings, were compared with the radiographic findings at final follow-up (mean 39 months). Results and conclusions. On MRI a low-intensity area or a low-intensity band in the new weight-bearing area extending over the acetabular edge on T1-weighted images was related to the presence of collapse on the radiographs at final follow-up. In hips with an area of absent activity in the new weight-bearing surface on bone scintigraphy, collapse was seen more frequently on radiographs at final follow-up than in hips without this feature. Bone scintigraphy was no more specific than radiography in predicting the outcome after TRO. We consider MRI to be superior to bone scintigraphy in predicting the occurrence of collapse, which is one of the major short-term problems after TRO.

Scintigraphic evaluation of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head

Scintigrams and radiographs of 36 femoral heads in 34 patients before and after Sugiokas transtrochanteric rotational osteotomy for osteonecrosis of the femoral head were investigated prospectively. Patients were followed for more than 3 years after the operation. The patterns of early scintigrams made within 3 months of the operation were classified into four categories. All 4 patients with a large cold area evidenced collapse within I year despite good recovery of the weight-bearing surfaces immediately after operation on conventional radiograms. Twenty-two hips with no cold area in the femoral head did not demonstrate collapse. Femoral head collapse after rotational osteotomy can be predicted by early postoperative bone scintigraphy.