Preservation of the Epiphysis and Growth Plate in the Surgical Management of Femoral Osteosarcoma in a Skeletally Immature Patient by Intercalary Resection and Biological Reconstruction: A Case Report

Osteosarcoma arises most frequently in the metaphysis around the knee and its management by limb salvage surgery in skeletally immature pediatric patients is extremely challenging. Common reconstructive methods such as endoprosthetic or biological reconstruction are not fully capable of dealing with durability-related and growth-related problems and their functional outcomes are not as good as those seen in adult cases. A definitive limb salvaging procedure in children that outperforms amputation or rotationplasty has not yet been established. Herein, we report a case of stage IV osteosarcoma in the femur of a 7-year-old boy that was safely managed with intercalary resection preserving the distal femoral growth plate and epiphysis, followed by biological reconstruction using a frozen tumor-devitalized autograft. Good response to preoperative chemotherapy and the diaphyseal location of the tumor enabled us to perform a tumor resection that spared the growth plate and preserved the native knee joint structure. Plate fixation over the growth plate was terminated by removing the locking screws in the epiphysis after 44 months, which restored growth capacity to some extent. At 50 months postoperatively, no recurrence or progression of the disease was observed. The patient uses an extension shoe and reports having little discomfort in his daily life despite having a restricted range of motion and limb length discrepancy. In conclusion, limb salvage with biological reconstruction in skeletally immature patients can provide an acceptable functional outcome, including minimized limb length discrepancy, if critical damage to the growth plate and articular components can be avoided.