外傷後の腓骨遠位部における腸骨稜血管柄再建：技術的注意点と長期経過観察

Large post-traumatic defects of the lateral malleolus are uncommon but present major reconstructive challenges, particularly in the presence of segmental bone loss, infection, or soft-tissue compromise. The lateral malleolus is essential for ankle stability, and its absence leads to mechanical imbalance and early degenerative changes. Traditional solutions-including non-vascularized grafts, allografts, arthrodesis, or fibular transfers-may be inadequate when biological conditions are poor or when three-dimensional reconstruction is required. Vascularized bone flaps offer improved union rates and enhanced resistance to infection. The vascularized iliac crest flap, although well-established in limb reconstruction, remains infrequently reported for distal fibula restoration.

Three patients with severe post-traumatic lateral malleolar defects were treated between 2002 and 2015 at two microsurgical centers. Reconstruction was performed using free vascularized iliac crest flaps based on the deep circumflex iliac artery. Flap configuration (osteo-muscular or osteo-cutaneous) was adapted to defect size and soft-tissue requirements. Technical details-including flap harvest, shaping of the iliac crest segment, fixation, and vascular anastomoses-are described. Clinical and radiographic outcomes were evaluated over 8-14 years.

All flaps survived without major postoperative complications. Radiographs demonstrated consistent osseous union between the iliac crest graft and tibia. All patients achieved full weight-bearing and stable ankle function. Mild-to-moderate radiographic osteoarthritis occurred at long-term follow-up but remained asymptomatic. Soft-tissue coverage was reliable, and no secondary flap procedures were required.

The free vascularized iliac crest flap is a dependable and versatile reconstructive option for extensive lateral malleolar defects. It provides stable ankle restoration, predictable union, and durable function, and should be considered when conventional grafting or fibular transfers are unsuitable, particularly in complex post-traumatic or infected environments.