A composite of massive frozen allograft and prosthesis replacement used in limb salvage surgery / 中华骨科杂志

ABSTRACT

Objective To analyze the effect of reconstruction for the proximal or distal femoral defect by a composite of massive frozen allograft and prosthesis replacement. Methods According to Enneking's classification, malignant bone tumors of the proximal or distal femur were widely resected in 28 cases. Reconstruction of the affected hip or knee joint after major joint removal was done by a composite of allograft and prosthesis. A conventional femoral component with a stem long enough to provide good fixation in the femoral shaft was threaded over a customized allograft. After the assembly had been reduced and checked for size and position, the allograft was cemented to the femoral component, and the composite was in turn cemented into the femoral shaft with PMMA. Results 26 patients were followed up from 6 to 78 months with an average of 41 months. 3 cases died within 18 months following operation; 4 case sustained recurrences within 8 months postoperatively, and underwent re-resection; and the others were alive without diseases. All patients had no dislocation, loosening or breakage of prosthesis. X-rays showed the time of bone healing between allograft and host femur was an average of 7.4 months (range, 5 to 11 months), and the rate of bone healing was 92% (24/26). Absorption was seen around allograft greater trochanter of femur in 9 cases and at femoral condyle in 6 cases. 13 cases with total hip composite replacement had good active extension-flexion degrees of an average of 85?( range, 71? to 124?), and 13 with total knee composite replacement had a rang of motion of 92?(range, 68? to 135?). The postoperative average ISOLS scale score of 26 cases by Enneking's system was 26.2 point (range, 22 to 28). Conclusion The clinical result demonstrated the composite of massive frozen allograft and prosthesis replacement has the advantages of both allograft and prosthesis. Its best indications are that the patients with a major femoral defect from benign or low grade malignant tumor have longer survival expectancy.