Reconstruction of bone and skin defects of medial malleolus with free composite flap of fibular head in children

Objective To explore clinical outcomes of reconstruction of bone and skin defects of medial malleolus with a free composite tissue flap of the fibular head in children.Methods First a gross anatomic observation was conducted to study the blood supply and anatomy of the blood vessels around the area of fibular head using 6 cadaveric specimens of children's lower limb (4 boys and 2 girls).Based on the gross observation, a free composite tissue flap of the fibular head was designed for the repair of bone and skin defects of medial malleolus in 8 children (6 boys and 2 girls, aged from 3 to 11 years).There were 7 cases of open injury and one case of closed injury.Seven right medial malleoli and one left medial malleolus were repaired.The osteoepiphysis was involved in all the cases.The bone defect area ranged from 2 cm×2 cm to 4 cm× 6cm, and the skin defect area from 3 cm× 6 cm to 8 cm× 10 cm.Results The gross anatomic observation revealed that the lateral inferior genicular artery is the principal blood supply to the free composite tissue flap of the fibular head.The lateral inferior genicular artery originates from the popliteal artery and runs to the fibular head by way of the lateral gastrocnemius muscle, collateral ligament, lateral meniscus and posterior aspect of the femoral bone.The artery course is constant.The initial diameter of the artery is 1.0±0.2mm, and its total length is 2.5 ± 0.4 cm.On average, the artery has 2 to 4 branches extending into the skin of the fibular head area.After clinical application, the flap survived in all the 8 cases.Follow-ups from 4 to 13 months showed bony union, fine shape of the medial malleolus reconstructed and satisfactory functional recovery of the ankle joint in all the 8 cases, with partial early closed osteoepiphysis in one case.Conclusion The free composite tissue flap of the fibular head has plentiful blood supply and is a good way to reconstruct bone and skin defects of the medial malleolus in children. Key words: Ankle injuries;  Reconstructive surgical procedures;  Fibula;  Child