Purpose. In this study we reviewed our use of the pedicled anterolateral thigh (ALT) flap in complex abdominal and pelvic reconstruction. We identified points of surgical technique that enhanced our results. In addition we identified the potential pitfalls of this flap.

Materials and Methods. Following approval of our Research Ethics Board we performed a retrostpective review of the medical records of 25 patients who underwent 26 pedicled ALT flaps performed consecutively between November 2001 and January 2007 inclusive. Parameters reviewed included age, sex, diagnosis, past medical history, defect dimensions, flap dimensions, anatomical sites and components requiring reconstruction, suprafascial or subfascial harvesting, number and type of perforators, closure of donor site, complications, and length of follow up.

Results. Thirteen males and 12 females with a mean age of 60 (range 35-86) underwent pedicled ALT flaps for complex abdominal and pelvic reconstruction. Five patients (20%) were diabetic, six (24%) were smokers, and fifteen (60%) had preoperative radiotherapy. Twenty-three patients had defects secondary to ablative procedures for primary, recurrent or metastatic malignancy. One had cutaneous manifestations of Crohn's disease, and one had a large ventral hernia secondary to previous abdominal wall resection for necrotizing fasciitis. Of those patients undergoing tumour resection there were 11 primary sarcomas (one chondrosarcoma, two dermatofibrosarcoma protuberans, three malignant fibrous histiocytomas, one angiosarcoma, two leiomyosarcomas, two liposarcomas), five recurrent sarcomas (two dermatofibrosarcoma protuberans, one chondrosarcoma and two liposarcomas), one primary squamous cell carcinoma (SCC), two metastatic SCC's, one primary adenocarcinoma, one metastatic adenocarcinoma, two metastatic malignant melanomas, and one metastatic malignant phaeochromocytoma. Mean size of defect was18.7 x 13.8 (range 10-30 x 7 – 30) centimeters. Mean size of anterolateral thigh flap was 16.9 x 9 (range 14-20 x 6-14) centimeters. The arc of rotation included the umbilicus, iliac crest, posterior superior iliac spine, and anterior anal margin. Twenty-two flaps were dissected subfascially and four suprafascially. In the subfascial group the harvesting extended beyond the cutaneous borders of the flap in six cases to increase the amount of vascularised fascia for abdominal wall reconstruction. The fascia was used to reconstruct the abdominal wall in a total of sixteen cases. There was a mean of 1.5 perforators per flap (range 1-4) of which 14% were septocutaneous. The donor site was closed directly in all but four cases, which required a split thickness skin graft. Complications included two complete flap losses (8%), one partial flap loss (4%) and five minor wound dehiscences at recipient sites, and delayed healing of four flap donor sites (15%)(two closed directly and two with split thickness skin grafts). All patients with complications, except one, had at least one factor contributing to poor wound healing (diabetes, smoking, or preoperative radiotherapy). One patient with a minor dehiscence subsequently died as a result of a small bowel fistula, psoas abscess and rupture of a false aneurysm in the ipsilateral external iliac artery. Mean follow up was 10 months (range 1-40 months). Useful points of surgical technique include suprafascial harvesting of the flap, the method of harvesting fascia, and its utilization to protect the pedicle, harvesting the anterolateral thigh flap as a composite flap with a portion of vastus lateralis, prudent preservation of large perforators that transgress through the lateral aspect of the rectus femoris muscle, combined use of the pedicled anterolateral thigh flap with a sartorius ‘switch', complete flap de-epithelialization to fill dead space, and simple conversion to a free flap when pedicle length is inadequate. Pitfalls identified included the increased risk of pedicle avulsion in the morbidly obese, the risk of atherosclerotic placque embolization in an atheromatous pedicle, and the potential inadequacy of thigh fascia for reconstituting abdominal wall integrity.

Conclusion. The pedicled ALT flaps is a versatile flap with a wide arc of rotation making it useful in complex abdominal and pelvic reconstruction. Variations in the surgical procedure for each patient can be used to enhance results, and an appreciation of potential pitfalls may help minimize complications.