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Abstract Background  We retrospectively reviewed 137 consecutive total hip arthroplasties performed with AML-A stems and Tri-Lock cups to see whether design modifications made to these components would achieve durable biological fixation in the Japanese population in whom developmental dysplasia of the hip (DDH) is relatively common. Patients from our initial clinical series using these components are available for more than 10 years’ follow-up. Methods  Between April 1988 and June 1994, we performed 137 total hip arthroplasties using the AML-A prosthesis for the patients with osteoarthritis of the hip joint. We excluded 26 hips with less than 10 years’ follow-up and five hips from patients who died before the 10-year follow-up. The mean follow-up for the 105 remaining THAs is 155.2 months (range 120–237 months). The average age of these patients at the time of surgery was 53.1 years (range 22–81 years). Results  In total, 17 THAs required component revisions. In seven cases, the first revision was limited to a liner exchange for polyethylene wear or osteolysis. Another seven hips underwent revision surgery for recurrent dislocation. Three cups have been revised owing to aseptic loosening. Because of the high incidence of wear-related revisions, Kaplan-Meier survivorship at the 15-year follow-up, using acetabular component revision for any reason as an endpoint, was 75.0% (95% CI 69.4%–83.8%). In contrast, no revision of the femoral stem was performed. Severe stress shielding occurred in 12 hips. Thigh pain was mild, however, and all of the femoral stems remained stable. Conclusions  Despite revisions for wear-related complications, the fixation achieved with these porous-coated components remained durable throughout the 15-year follow-up. Acetabular osteolysis has been associated with cup reoperation, but femoral stress shielding has never resulted in stem loosening. [ABSTRACT FROM AUTHOR]

Abstract Background  We have previously offered data suggesting a positive linkage of postoperative up-regulation of systemic angiogenic activity and postoperative progression of pulmonary metastasis in osteosarcoma. The finding that the significant down-regulation of endostatin was critical in angiogenic elevation after primary tumor removal suggests that endostatin is a candidate for antiangiogenic therapy for osteosarcoma. Methods  In the current study, we evaluated the effect of antiangiogenic therapy using endostatin on postoperative progression of pulmonary metastasis from osteosarcoma. Mouse osteosarcoma cell line LM 8 cells were inoculated in subcutaneous layer of nude mice. Two weeks after tumor inoculation, the primary tumor was removed surgically, and antiangiogenic therapy using adenovirus encoding endostatin expression vector (Ad5CMV-mEnd) was performed. Two weeks after the antiangiogenic treatment, pulmonary metastasis was evaluated by counting the number of metastatic nodules. The evaluation of systemic angiogenic activity was performed using Matrigel plug assay. Results  Two weeks after the viral injection, mice were sacrificed, and the macroscopic pulmonary metastases were counted. Notably, the number of pulmonary metastases was smaller in the mice injected with Ad5CMV-mEnd than in controls, accompanied by significant suppression of systemic angiogenic activity. In addition, the sizes of the pulmonary metastases of the mice injected with Ad5CMV-mEnd were smaller than in the control group. Conclusions  Our results indicate that antiangiogenic therapy using endostatin has the potential to prevent postoperative progression of pulmonary metastasis from osteosarcoma. Although this therapeutic strategy cannot provide a cure for osteosarcoma, it should enable osteosarcoma patients to coexist with dormant pulmonary metastasis and lead to improvement of their prognosis. [ABSTRACT FROM AUTHOR]