Applications of the medial femoral condyle free flap for foot and ankle reconstruction

Background: Avascular necrosis (AVN) or persistent nonunion occurs in situations of poor vascular supply. Some specific situations that plague the foot and ankle surgeon are talus nonunion, talus AVN, navicular AVN, and failed ankle arthrodesis with bone loss. The medial femoral condyle (MFC) flap has emerged as a popular source of vascularized corticocancelous bone. We present a series of cases demonstrating the versatility of the MFC flap in complex foot and ankle pathology. Methods: A retrospective review was completed of all MFC flaps used in the foot and ankle over the past 5 years. Five patients were identified (average age 48). Surgical indications included talar AVN and ankle arthritis, talar nonunion, and navicular AVN. All patients had undergone conventional bone grafting techniques, which failed, prior to being treated with a MFC free flap; this series of patients did not possess significant medical comorbidities. Fixation techniques included compression screw fixation, plate osteosynthesis, or fine wire external fixation. The average follow-up was 20 months (range 8 to 40 months). Results: There was a 100% flap success rate with no returns to the operating room for thrombosis. The volume of the bone flaps was 5.6 cm3 (range 1 cm3 to 12 cm3). The average follow-up time was 20 months (range 8 to 40 months). All cases resulted in union, and full weight bearing status was achieved at a mean of 23.8 weeks (range 10 to 52 weeks) postoperatively. Conclusions: Vascularized bone transfer in the form of the MFC free flap was a valuable method for foot and ankle reconstruction. The MFC flap provided an alternative for those defects that were smaller then 3 cm in length. In our experience, for small bone defects requiring vascularized bone, the MFC flap is currently the ideal donor location supplanting the iliac crest.