Case Report: Massive allograft resorption after reconstruction of large fibular bone defect secondary to osteomyelitis

Introduction In skeletally immature children, Cierny–Mader type IV chronic hematogenous osteomyelitis can result in extensive fibular necrosis and segmental bone loss, yet the optimal reconstructive strategy for this type of defect remains controversial. This failed case provides a rare clinical reference for the management of ultra-long diaphyseal bone defects in children. Case history We report a 12-year-old male with a 26 cm fibular defect following debridement for chronic hematogenous osteomyelitis. The patient was treated with a two-stage Masquelet technique, and the second-stage reconstruction was performed using massive allograft combined with enriched bone marrow stem cells. Comprehensive analysis of serial clinical data, intraoperative findings, and long-term imaging follow-up identified multiple factors contributing to graft resorption, including the proportion of allograft used, stem cell viability and quantity, the timing of the second-stage procedure, the lack of rigid internal fixation, and the unique characteristics of pediatric osteoblastic and osteoclastic activity. Ultimately, repeated imaging confirmed extensive resorption of the transplanted allograft, indicating failure of the bone defect reconstruction. Conclusions In this single case of a large fibular defect secondary to osteomyelitis in a skeletally-immature child, massive allograft combined with bone-marrow-derived cells resulted in extensive graft resorption despite acceptable final limb function. This case highlights several important clinical considerations derived from our experience: prolonged interval between two-stage Masquelet reconstruction, extensive volume of allograft, insufficient mechanical stability, and pediatric high-bone-turnover status may collectively predispose to graft resorption. For fibular defects in growing children, acceptable functional outcomes may be achieved via soft-tissue-mediated functional union even when bony union cannot be accomplished. Observations from this individual case should not be generalized to all similar patients.