Metastatic instability at the proximal end of the femur. Comparison of endoprosthetic replacement and plate osteosynthesis.

A retrospective study was performed of the surgical treatment of metastatic lesions of the proximal femur in 50 patients. In 25 consecutive cases a megaprosthesis was implanted; compound plate osteosynthesis was performed in another 25 consecutive patients. Indications for surgical treatment were pathological fractures or, for prophylactic treatment, lesions of the femoral cortex exceeding 2.5 cm in diameter or affecting half the diameter of the bone or more. In all patients capable of walking preoperatively mobility was regained. Immediate full weight-bearing stability was obtained in all patients. Group analysis showed that the functional rating of the hip joint was unchanged, i.e., good or excellent, in all patients with compound osteosynthesis, compared to only 68% in the endoprosthesis group. Pain relief was excellent or good in 84% and 88% respectively. Dislocation of the tumor prosthesis occurred in 3 patients. Closed reduction was possible in 2 cases. Local recurrence was higher in the patients undergoing plate osteosynthesis, as was the frequency of tumor-related implant failure. Postoperative survival averaged 14.7 months and 12.1 months respectively.