Internal hemipelvectomy and endoprosthetic pelvic replacement: long-term follow-up results

We report on our experiences with internal hemipelvectomy followed by an implantation of a endoprosthetic pelvic replacement (EPR) performed in 15 patients over a period of 15 years. Our primary aim was to determine the indications for this procedure because of its high rate of complications. Due to the malignant character of the disease and the biomechanical stress on the anatomical region, the demands on the surgeon are high. The most important factor is a sufficiently wide resection of the primary tumour because most are chondrosarcomata which do not respond to other therapies. In addition, the malignant character of the tumour has the greatest influence on the long-term results. Internal hemipelvectomy and endoprosthetic pelvic replacement are accompanied by a high rate of operative and postoperative complications. Nevertheless, nearly full anatomical and functional reconstruction can be obtained provided a medium level of function is accepted. Follow-up results of the remaining six still living patients were evaluated by means of three different scoring systems. All patients had only a medium score but emphasised subjective acceptance of the endoprosthetic pelvic replacement even when removal was necessary later on. Because of the lower functional outcome of alternative operative procedures such as pseudarthroses and arthrodeses and problems with the replantation of autoclaved autografts or implantation of an allograft, internal hemipelvectomy combined with endoprosthetic pelvic replacement is the treatment of choice for these specific acetabular lesions, provided a complete resection is feasible. Otherwise, an external hemipelvectomy is necessary because even alternative limb-salvaging procedures must incorporate the same complete resection of the tumour. In cases of metastatic lesions, internal hemipelvectomy and endoprosthetic pelvic replacement are indicated relatively because of the systemic character of the disease. The procedure should be considered only when resection of a solitary metastasis enables a cure and/ or prolongation of ilfe with an improved quality of life.