We performed 114 consecutive primary total hip arthroplasties with a cementless expansion acetabular component in 101 patients for advanced osteonecrosis of the femoral head. The mean age of the patients at surgery was 51 years (36 to 62) and the mean length of follow-up was 110 months (84 to 129).

The mean pre-operative Harris hip score of 47 points improved to 93 points at final follow-up. The polyethylene liner was exchanged in two hips during this period and one broken acetabular component was revised. The mean linear wear rate of polyethylene was 0.07 mm/year and peri-acetabular osteolysis was seen in two hips (1.9%). Kaplan-Meier analysis indicated that the survival of the acetabular component without revision was 97.8% (95% confidence interval 0.956 to 1.000) at ten years.

Our study has shown that the results of THA with a cementless expansion acetabular component and an alumina-polyethylene bearing surface are good.

Aims: To evaluate the early midterm outcomes of primary total hip arthroplasty (THA) using Hydroxyapatite (HA)-coated on smooth surface acetabular component with 28 mm metal head on polyethylene liner articulation. Methods: Seventy primary THA in 63 patients with HA-coated acetabular component were performed consecutively between June 1993 and August 1996. Fifty-four cases were eligible for follow-up of average 71 months (48–104) and the mean age of index operation was 49 years (23–71). The clinical results were analyzed by modiþed Harris hip score, and the radiologic evaluation in terms of stability, polyethylene wear rate (Dorr method), osteolysis around acetabular component was done. Results: Mean Harris hip score improved from 50.9 to 82.2 at the last follow-up. Excellent or good results were found in 38 cases (70%). Eight cases (15%) were unstable radiologically. Pelvic osteolysis was found at 18 cases (33%). The mean polyethylene wear rate was 0.146 mm/year (0.01–0.45). Wear rate of hip dyaplasia was greater than osteonecrosis signiþcantly (p< 0.05). Seven cases (13%) were revised (5 mechanical failures, 2 deep infections). Any bone ongrowth was not found during revision surgery for loose components. Complications included 5 heterotrophic ossiþcations, 2 deep infections, and 1 nonrecurrent dislocation. Conclusion: Primary THA using HA-coated on smooth surface acetabular component showed unsatisfactory clinical results, accelerated polyethylene wear rate accompanying high incidence of osteolysis, and high loosening rate due to lack of bony ongrowth at early midterm.

In countries where Confucianism is popular, it is extremely difþcult to get allograft. Twenty seven cases of limb salvage with recycled autogenous bone were performed after wide resection of malignant tumors. Recycling was done in 9 cases with pasteurization and in 18 cases with irradiation. Pasteurization was done in 60¡-30minutes with thermostatic saline bath. Irradiation was performed in sterile plastic jar þlled with saline. 25 Gy radiation was given þrst anteroposteriorly and then another 25Gy posteroanteriorly. Internal þxation was done either with plate and/or intramedullay nail, and in 13 cases, intramedullary packing of bone cement was added. Among 9 pasteurized cases, 5 were intercalary diaphyseal resection, 2 whole bone resection of metatarsals, and 2 prosthesis-pasteurized bone composite arthroplasty. Among 18 irradiated cases, 12 were osteoarticular, and 6 intercalary resections. Follow-up period was 16 to 112 months (mean: 46 months). There was no recycled bone-related local recurrence. Time for union varied greatly.(4 to 14 months). There was no statistical difference in union time between pasteurized and irradiated bone (Wilcoxon rank test). Complications were 9 delayed or non-union, 3 fractures of recycled bone, and 2 cases of separation-resorption of growth plate. Irradiation seems much better than pasteurization because it could preserve mechanical property of articular cartilage and soft tissues such as tendon and capsule. We recommend intraoperative-extracorporeal irradiation as a good substitute for osteoarticular allograft because soft tissue attachment could be saved. Intramedullary packing of bone cement was proved as a good method to enhance the stability of þxation and to prevent fracture.

Introduction: The purpose of this study was to compare the results of the efficacy of two decompressive methods (multiple drilling vs standard core decompression) for the treatment of precollapse osteonecrosis of the femoral head.

Methods: The results in a consecutive series of 54 patients (65 hips) who had undergone multiple drilling (31 patients, 35 hips) or core decompression (23 patients, 30 hips) for the treatment of precollapse osteonecrosis of the femoral head between September 1991 and July 2001 were reviewed. The average duration of follow up was 60.3 months (range, 24–103 months) in the multiple drilling group and 44.8 months (range, 24 to 84 months) in the core decompression group. The presence of collapse and radiographic progression in each group was evaluated prospectively with collapse of the femoral head defined as a failure. Harris hip scores (HHS) were used to evaluate clinical status preoperatively and at the most recent follow up.

Results: Radiographically and clinically, high failure was significantly related to the larger size and laterally located lesion (LHI of less than 12%, Urbaniak IIC, Ohzono IC and Kerboul index of more than 240 degrees) in both groups. The average preoperative and the last HHS was 86.7 to 73.7 in the core decompression group and 87.0 to 74.6 in the multiple drilling group. Compared to the core decompression group, the multiple drilling group had significantly longer times before collapse (mean 42.3 months vs 22.6 months, p=0.011) and a lower rate of collapse within 3 years after operation (55.0% vs 85.7%, p=0.03).

Discussion: Decompressive methods have worse outcomes in case of lesions of larger size and lateral location, even in precollapse stage. Multiple drilling has significantly longer time before collapse and a lower rate of collapse within 3 years after operation than standard core decompression.

Introduction: This study was designed to investigate the feasibility and advantages of minimally invasive plate osteosynthesis of tibia fractures.

Methods: In a prospective study, 24 cases of unstable tibial fractures were stabilized with a narrow LC-DCP (Limited Contact-Dynamic Compression Plate) inserted using minimally invasive percutaneous plate osteosyn-thesis technique. The technique consisted of 3 major steps: 1) reduction of fracture with or without distractor; 2) pre-contoured plate insertion percutaneously at the stab incision distant to fracture site; 3) plate fixation to the tibia percutaneously inserted screw. All the procedure was done under fluoroscopic guide. Between January 1998 and March 1999, we operated 16 proximal or distal periarticular fractures, 5 segmental fractures, and 3 mid-shaft fractures of adolescents that had still open physis. 18 fractures were closed, and 4 were open.

Results: 22 of 24 cases healed without second procedures such as bone graft or correction of angular deformity. There was no infection except 1 case of superficial infection that was healed with early removal of plate. There were 3 cases of screw breakage, but no procedure was required. At the follow-up, 2 patients were healed with > 5 degree varus alignment and > 10 degree internal rotation. All the patients had good knee or ankle function.

Conclusion: The authors feel confident that the minimally invasive technique for plate osteosynthesis of tibial fractures that would be inappropriate for intramedullary nailing will prove to a feasible and worthwhile method of stabilization, while avoiding the severe complications associated with the other methods.