Growing endoprostheses for primary malignant bone tumors.

Twenty years of experience with the use of growing endoprostheses for limb salvage in skeletally immature patients is reported. Alternatives for the management of primary malignant bone tumors in this group of patients are amputation, rotationplasty, and allograft or autograft reconstruction. The development of the currently used implant is charted, with commentary on the complications and difficulties which gave rise to design changes. Over this period, 123 expanding endoprostheses have been inserted in 108 patients in this institution, and the results of a series of 54 consecutive distal femoral replacements are reported. The mean functional score was 72%, and the local recurrence rate was 11%. The technique was successful in maintaining limb-length equality. We conclude that in specialized centers of orthopedic oncology that utilize an endoprosthesis with proven reliability of the expansion mechanism, the short- and long-term results of this technique justify its continued use.