Pre- and postoperative imaging of vascularized fibular grafts

Free vascularized fibular grafting, in which the peroneal artery is harvested with the fibula, is a popular procedure for filling osseous defects and for treatment of femoral head avascular necrosis. Preoperative vascular imaging is required in all patients to detect the origin of the peroneal artery, to measure the length available for the vascular pedicle, and to evaluate for the normal continuation of the three major vessels of the lower leg. Magnetic resonance imaging of the lower leg with use of gradient-recalled acquisition in a steady, state was performed in 35 patients to evaluate vascular anatomy. Surgical correlation was available in 91% of cases, and in these 100% accuracy was demonstrated. Postoperative radiographs showed that grafts placed for osseous defects in the upper extremity were incorporated and hypertrophied extremely quickly, while those placed in the major weight-bearing bones of the lower extremity were much more prone to complications including delayed union, fracture, and infection. Vascularized grafts placed in the femoral head and neck for avascular necrosis incorporate only in the cephalic portion and should be watched carefully for signs of early and progressive femoral head collapse.