Microvascular Fibular Flap for Traumatic Humeral Defect in an Infant: A Case Report and Literature Review.

Microvascular fibular flaps are an established option for reconstruction of large segmental bone defects, but their use in infants following trauma is exceptionally rare. A six-month-old male infant sustained a gunshot wound causing a 5-cm humeral diaphyseal defect. Definitive reconstruction at nine months of age employed a 7-cm osteocutaneous fibular free flap with a 4 × 2 cm skin paddle. The graft was inverted and fixed intramedullary with a K-wire; microvascular anastomoses connected the peroneal artery to a proximally transposed radial artery and flap veins to superficial veins using 10-0 nylon. Early union occurred within one month. At four-year follow-up, graft hypertrophy and full limb function were observed, with only mild donor-ankle valgus. This case demonstrates that vascularized fibular transfer is feasible and effective even in infancy when performed by experienced microsurgical teams and highlights technical modifications that facilitate safe anastomosis in diminutive vessels.