Coping with Extensive Bone Loss: The Use of Megaprosthetic Replacements for Difficult Knee Revisions

Dealing with extensive bone loss is one of the more difficult challenges in revision total knee arthroplasty. Occasionally, osteolysis, bone destruction due to infection, or fracture cause destruction that precludes the use of standard revision components. In this scenario, megaprosthetic reconstruction may be considered. Used for years in oncologic reconstructions, modular endoprostheses allow any amount of bone to be substituted. In the knee, either distal femoral or proximal tibial replacements can be performed. Rehabilitation of a distal femoral replacement parallels that of knee revision, whereas proximal tibial rehabilitation is somewhat different owing to the reconstruction of the extensor mechanism. Although somewhat different from that arthroplasty, the technique for bony resection and megaprosthetic reconstruction is applicable to arthroplasty surgeons or general orthopedic surgeons with revision arthroplasty experience. This reconstructive technique should be within the armamentarium of any surgeon who performs complex revision arthroplasty surgery.