Function of oncological endoprosthesis in recurrent osteosarcoma of distal femur

Abstract

Endoprothesis is the commonly used method of segmental reconstruction after bone tumor resection around knee. To achieve stability after extensive removal of knee structures, hinged endoprostheses are usually being preferred as a limb salvage procedure. Despite advances in diagnostics and preoperative tumor chemotherapy and radiotherapy, as well as meticulous intraoperative preparation, local tumor recurrence is still possible. We analyzed 22 patients with osteosarcoma in distal femur who underwent the knee arthroplasty with modular replacement system between 2002 and 2007. Three of them (two females aged 33 and 44 and one male aged 29) developed local recurrence 7, 9 and 12 months after operation. All of them were offered the amputation or metastatectomy, as well as further chemotherapy, and all refused. Reasons for refusal included disseminated disease, uncertain prognosis of amputation treatment and still good functional outcome despite existing tumor around the prosthesis. Two of the above mentioned patients deceased from disseminated disease 7 and 11 months later, one patient is still being followed 10 months long. Clinical examinations have shown the effective and satisfactory prosthesis functions in reported patients during the whole observation period. We have concluded that limb salvage surgery with implantation of hinged knee endoprosthesis in tumors in distal femur provide satisfactory functional outcome even when local tumor recurrence is found.