Results of free vascularized fibula grafting for allograft nonunion after limb salvage surgery for malignant bone tumors

The purpose of this study was to assess the results of free vascularized fibula grafting (FVFG) in the treatment of allograft fracture nonunion after limb salvage surgery for malignant bone tumors.A retrospective study was performed on 8 patients who underwent FVFG for allograft fracture nonunions. All had prior tumor resection and allograft reconstruction for osteosarcoma (n = 6) or Ewing sarcoma (n = 2) of the femur (n = 3), tibia (n = 2), humerus (n = 2), or ulna (n = 1). All patients failed an initial course of immobilization; 4 patients failed prior open reduction and internal fixation with autogenous nonvascularized bone grafting. Average age at the time of FVFG was 14 years. Average follow-up was 44 months.The FVFG resulted in successful bony healing in 7 of 8 patients, providing pain relief, limb preservation, and restoration of function. One patient developed an infection requiring fibula removal and staged prosthetic reconstruction. Additional complications requiring further treatment included limb-length discrepancy, additional allograft fracture, and wound infection.The FVFG is an effective treatment option for allograft nonunion after limb salvage surgery because it provides both the mechanical stability and biological stimulus for bony healing. Attention to internal fixation, limb alignment, and microvascular principles is essential to prevent complications and allow for the best functional outcomes.