Efficient design of split anterolateral thigh flap in extremity reconstruction

Background: Irregularly shaped and three-dimensional soft-tissue defects in the extremities are difficult to cover precisely and efficiently. One strategy is to use the anterolateral thigh flap with two perforators and split the flap into two subunits based on separate perforators. The subunits can be rearranged into various geometric configurations to cover defects with nonelliptical shapes. Such a strategy emphasizes harvesting an elliptical anterolateral thigh flap with a narrower width to allow for primary closure in most cases. This avoids the need for skin grafting and reduces donor-site morbidity. Methods: From 2002 to 2010, 15 patients with upper and lower limb defects were treated with split anterolateral thigh flaps. There were nine male patients and six female patients. The mean age of the patients was 40.6 years (range, 18 to 64 years). The shape of each defect was classified as arrow-shape, hourglass-shape, triangular, or three-dimensional. Results: All split flaps (n = 31) survived without vascular problems. Two split flaps demonstrated margin necrosis without critical structure exposure. Only one donor site needed skin grafting. All other donor sites were closed primarily. Conclusions: The split anterolateral thigh flap is an effective strategy for covering irregular and three-dimensional defects in the extremities. It allows efficient use of the harvested flap and minimizes trimming and discarding unused flap parts. This decreases the area of skin graft needed for donor-site coverage and may even be able to achieve primary closure.