Intercalary Segmental Allografts Reconstruction In Bone Defects After Resection Of Limb Primary Bone Tumor

Background:The application of massive allografts is a reconstructive biologic option for intercalary bone defects in limb-salvage surgery. Intercalary allografts usually maximize functional outcome by maintaining the articular cartilage and joint ligaments and can be used to preserve adjacent growth plates in skeletally immature patients. However, there’s still no optimal indications as reports on failure and complication rates in larger populations remain scarce. And it’s unclear which are the optimal fixation methods for intercalary allografts. The purpose of the current study was to investigate the effects of massive intercalary allografts on osseous reconstruction after limb bone tumor resection comprehensively.Methods:All consecutive patients reconstructed with intercalary allografts (epiphyseal preserved) after tumor resection in the long bones or metaphyseal during 2005 to 2014 were evaluated. Our series included 62 patients with a median age of seventeen years. The most common diagnoses were osteosarcoma (75.8%), chondrosarcoma (12.9%), and Ewing sarcoma (4.8%).Eighty seven point one percent of tumors were localized in the femur or the tibia. The average length of allografts was 16.7±5.4cm. Reconstructions were fixed with intramedullary nails in only three patients and plate(s) in all others.Results:At a median follow-up of 53 months,12 patients were dead and 17 developed local recurrences or metastases. Explantation of failed allografts occurred in 7 patients. And 4 patients underwent ablative surgery.5-years allograft survival was 87.4%. For 56 patients without local recurrence, complications occurred in 66.1% and reoperations were conducted in 48.2% of these patients. Higher complication rate was seen in the femur (p=0.03). The major complications were fracture (21.4%), fixation failure (35.7%) and nonunion (44.6%). Non-Bridging osteosynthesis was the most important risk factor for fracture (66.7%vs.16.0%, p=0.01).The nonunion rate for diaphyseal junctions was higher(37.9%) than the rate for metaphysealones(11.1%)(p=0.01).Conclusions:Massive intercalary allografts are an acceptable and reliable alternative after tumor resection. But a high rate of local complications must be anticipated. Diaphyseal junctions have higher nonunion rates than metaphyseal junctions. To reduce the number of complications, we recommend applying bridging osteosynthesis with use of plate(s) fixation.