New Method of Extensor Reconstruction Using Bone-to-Bone Fixations After Resection of Proximal Tibial Malignancies

Purpose: The proximal tibia is the most technically demanding site with respect to limb salvage surgery. Reconstruction of the extensor mechanism is the most important determinant of the functional outcome for patients after a proximal tibial resection. This study presents a new surgical technique and the results of reconstruction of the extensor mechanism after prosthetic replacement of the proximal tibia. Materials and Methods: The extensor mechanisms in 4 cases of high-grade osteosarcoma and 1 case of parosteal osteosarcoma of the proximal tibia were reconstructed with bone-to-bone fixation methods. After excision of the proximal tibia, we resected the distal femur and constructed a composite with the resected distal femur, the low-heat-treated autogenous proximal tibia, and an endoprosthesis. The patella was fixed to the resected offloaded distal femur. Results: All the patients were followed up for a minimum of 1 year, and all achieved normal extensor muscle strength of the knee joint as well as a good functional outcome. Conclusion: Reconstruction of the extensor mechanism of the knee after prosthetic replacement of the proximal tibia with bone-to-bone fixation, decreases the amount of the extension lag and provides a good functional outcome. We believe this method is a reliable surgical technique, especially when the patellar tendon cannot be saved or primary reconstruction with a soft tissue technique, has failed.