[Tumor endoprosthesis in malignant bone tumors].

In the Department of Orthopedics at the University of Vienna, tumor endoprostheses have been implanted after resections of tumors of the upper extremities since 1974 and of the knee joint since 1976. For replacement of the humerus after tumor resection, a system of modular tumor endoprostheses was developed very early. Initially, it was ceramic and later on made of titanium alloys, which were also implanted in combination with custom-made prostheses with cementless stem-plate fixation in 57 patients until February 1990. In 43 of these patients (75.4%) adequate resection (2 radical and 41 wide) had been performed. Of 49 patients with a follow-up period of at least 24 months, 36 patients had a mean disease-free survival time of 106.1 months. Between 1976 and 1981, 16 custom-made endoprostheses were used after tumor resection of the knee joint. Since 1982 we have used a modular system of tumor endoprostheses suitable for replacement of the proximal and distal femur, proximal tibia, total femur and total knee joint. Of 75 patients who had been operated on up to February 1990, 67 patients (89.3%) had undergone adequate resection (2 radical and 65 wide). Out of 32 of these patients, 24 (75%) exhibited a disease-free survival time of at least 24 months (mean 48.2 months). Out of 213 patients with resection/reconstruction (160 endoprostheses), 77.8% had a survival time of at least 24 months, a results which is considerably better than in 146 patients with amputation in which case the respective value was 69.4%.(ABSTRACT TRUNCATED AT 250 WORDS)