[Endoprosthetic reconstruction after wide resection of primary bone tumor around the knee].

Objective: To evaluate the effect and complication of the endoprosthetic reconstruction after wide resection of primary bone tumor around the knee.

Methods: The retrospective analysis was performed on 83 patients undergoing the prosthetic reconstruction after the resection of the primary tumor around the knee between December 1995 and December 2005. All the diagnoses were pathologically confirmed (58 patients with osteosarcoma, 2 with osteosarcomatosis, 1 with parosteal osteosarcoma, 4 with malignant fibrous histiocytoma, 13 with giant cell tumor of bone, 1 with leiomyosarcoma, 2 with Ewing's sarcoma, 2 with chondrosarcoma). The distal femur group was involved in 44 patients, proximal tibia group in 34 (including 33 deficit in proximal tibia, 1 deficit both in proximal tibia and distal femur), total femur replacement group in 5. After operation, the Musculoskeletal Tumor Society (MSTS) score was used to evaluate the recovery of their corresponding functions.

Results: The follow-up for 12 - 130 months (with a median of 41 months) revealed that the 3-year survival rate of the prosthesis was 88.2%, and the 5-year survival rate was 82.1%. As for the complications, local recurrence developed in 6 patients, peri-prosthesis infection in 2 patients, aseptic loosening in 2 patients. The mean MSTS core was 25.0 (19.0 - 29.0) in the distal femur group, 24.4 (17.0 - 28.0) in the proximal tibia group, and 19.0 (16.0 - 21.0) in the total femur replacement group. As to the statistical analysis, the function of the former two groups were greater than the latter one (F = 11.666, P < 0.001), however, there was no significant difference between the former 2 groups (F = 0.813, P = 0.370).

Conclusions: Taken together, the tumor prosthesis gives a satisfactory functional outcome after the tumor around the knee is removed with a lower incidence of complication.