The current study consists of an outcome review of a consecutive series of 92 patients with knee
arthrodesis using an allograft, done for malignant or aggressive
tumors in two centers on different continents during a period of 18 years (mean followup, 5 +/- 4 years). The data were compiled by creating a computerized file using the information provided by both centers. Seventy-five of the patients (81%) had high-grade nonmetastatic
tumors (Stage II), mostly
osteosarcoma. In addition seven (8%) had
metastases at outset (Stage III) and the remaining 10 (11%) had benign disease, mostly
giant cell tumor or revision procedures for failed allograft or
total joint replacement. Seventy-two patients (78%) had distal femoral lesions (78%) whereas the proximal tibia was the site of the
tumor in 20 patients (22%). The average age of the patients was 23 +/- 16 years; 51 were males and 41 were females.
Tumor complications were a major problem for patients in the series. Thirty-four percent of the patients died, 47% had
metastases develop, and 9% had a local recurrence. Allograft complications included an
infection rate of 20%, a fracture rate of 25%, and a nonunion rate of 44%. Repeat surgery was required for more than 50% of the patients with 26 requiring one additional operation, 11 requiring two, and 10 requiring three or more operations. Nineteen of the patients required an
amputation (20%), only four of which were for recurrent
tumor. When these data were compared with data for a control series of 880 patients with allografts other than allograft
arthrodeses, the complications were greater and the outcome less successful, suggesting that other approaches should be considered unless there are special indications for this procedure.