Endoprosthetic reconstruction for the treatment of musculoskeletal tumors of the appendicular skeleton and pelvis.

BACKGROUND: Excision of a bone tumor requires reconstruction if limb salvage is a priority. Reconstruction with an endoprosthetic implant is preferred in our unit, as the patient typically can return rapidly to full weight-bearing and functional activities. Long-term complications, such as deep infection, aseptic loosening, and mechanical failure of the implants, have led to concerns about the efficacy of reconstruction and the ability to revise failed implants while maintaining limb salvage in the longer term. The purpose of this study was to investigate the survival of endoprosthetic reconstructions in the medium to long term in order to determine the factors associated with their failure.

METHODS: A consecutive series of 776 patients underwent endoprosthetic reconstruction following resection of a bone tumor at a minimum of ten years prior to this investigation. One hundred and nine children with a so-called growing endoprosthesis were excluded as they often require revision to an adult prosthesis near skeletal maturity. Six patients were excluded because of a lack of adequate follow-up data, leaving 661 patients for analysis. Kaplan-Meier survival analysis of the implant was performed, with implant revision for any cause (infection, local recurrence, and mechanical failure), mechanical failure alone, and amputation used as the end points.

RESULTS: The mean duration of follow-up was fifteen years for patients who survived the original disease. Two hundred and twenty-seven patients (34%) had revision surgery because of mechanical failure (116 patients), infection (seventy-five patients), and locally recurrent disease (thirty-six patients). Implant survival at ten years was 75% with mechanical failure as the end point and 58% with failure from any cause as the end point. The limb salvage rate was 84% at twenty years.

CONCLUSIONS: We believe these medium to long-term results with first-generation endoprostheses are encouraging and justify the continued use of endoprostheses for reconstruction following the excision of a bone tumor.