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The need for a better roentgenographic evaluation of implant behavior in long-term prosthetic replacement of the proximal femur was considered. The authors present the results of a group of 13 patients belonging to a wide range of ages, with more than ten-years follow-up after tumor resection, and replacement characterized by bipolar cup and non-cemented stem. A new X-ray film acquisition and evaluation method was devised. Results confirmed the good behavior of bipolar reconstructions in patients of different ages, whose sockets were still intact. In younger patients, the prevalent bipolar movement was in the outer bearing, thus limiting polyethylene particulate debris formation. However, debris formation did not significantly affect the bone/stem relationship as only one loose stem was observed in a bone submitted to radiotherapy.

Over the last 10 years at the Ist Orthopaedic Clinic of the Rizzoli Institute more than 350 cases of massive bone homoplastic cadaver-retrieved reconstruction were carried out, after bone tumor resection. We reported the postoperative management indicated to the patient to prevent complications and to improve functional results. The indications protocol includes time required for immobilization, motion, and partial and total loading; functional and radiographic results expected. Finally, these indications are specified for site of reconstruction and fixation chosen.

The authors report their experience in the histologic study of massive allografts, explanted as a result of oncological, mechanical or biological complications. The study was conducted according to the method of inclusion in methyl methacrylate that does not involve decalcification. A description is provided of all of the phases of fusion between graft and host bone in the site of the osteotomies, as well as distribution of revascularization and rehabilitation of the graft, attachment of the soft tissues, and finally, modifications in the joint cartilage of the osteoarticular grafts. The allograft must be considered to be osteoconductive, and is only weakly osteoinductive. Incorporation of the graft is a slow and incomplete process that follows sequential phases. The Volkmann's canals in the osteotomies constitute the preferred paths for rehabilitation of the graft that is on the order of millimeters on the surface and centimeters in the site of the osteotomies. The greatest modifications have been observed in the joint cartilage. The cartilaginous cells appear to be vital only from a morphological point of view.

2,123 cases of primitive malignant bone tumors were collected from January 1982 to December 1992 at the Registry of Rizzoli Orthopaedic Institute. General data (name, age, gender, site, diagnosis) and histological and imaging documentation for each patient were filed. Considering the incidence of these tumors, we can assume that this registry (with contribution of more than 50 institutions) collect about 50% of italian cases of primitive malignant bone tumors. This registry permits informations regarding epidemiology, diagnosis and therapy of these rare neoplasms.