Short and long term failure of the modular oncology knee prosthesis.

This retrospective study investigated the modes of implant failure in 80 patients with modular oncology knee prostheses. Twenty patients (25%) required revision: 12 (60%) for stem loosening, 6 (30%) for bearing failure, and 2 (10%) for infection. Patients with bone sarcomas survived longer; however, long-term prosthetic survivorship was a problem. A higher failure rate was found in patients with tibial tumors and with adjuvant treatment of chemotherapy. This study demonstrates for improved long-term survivorship of modular oncology knee prostheses, there must be improvement in the methods of stem fixation, prosthetic materials, and bearing mechanics.