PURPOSE: Recent advances in perforator flap surgery have provided the reconstructive surgeon with a variety of options for lower extremity defects. We sought to establish an algorithm which maximized the benefits of perforator flaps in a North American reconstructive population. Three principles inform the algorithm: 1) Make all efforts to achieve a primary closure of the free flap donor site while replacing lost skin with new skin (instead of muscle with grafted skin) 2) Use flap donors as close to the wound as possible to minimize the iatrogenic extension of morbidity and maximize the similarity of donor and recipient site characteristics 3) If the size of the wound precludes closing the flap donor site primarily then resort to a muscle flap in order to leave the unaesthetic area in its post-traumatic location.
METHODS: A retrospective review of all below-knee microvascular reconstructions by a single surgeon at two trauma centers over 36 months was performed. An algorithmic approach was followed according to defect width. Wounds less than 4cm were treated with forearm flaps, wounds 4-6cm were treated with proximal peroneal perforator (PPP) flaps, wounds 6-12cm were treated with anterolateral thigh (ALT) flaps, and wounds over 12cm were treated with skin-grafted muscle flaps. From September 2005 to August 2008, forty-one patients from 13 to 75 years of age underwent lower extremity free flap reconstruction for wounds at the knee level or below.
RESULTS: Data was reviewed for 40 of 41 patients. The mean age was 40.7 years (SD +/- 16.4, range 13-75). The majority of the patients were male (75%) and trauma was the most common indication for surgery (65%). Microvascular reconstructive success rate was 97.5%, with one flap failure (2.5%). Primary closure of the donor site was achieved in 35 of 40 cases (87.5%). Flap preference was related strongly to wound size: forearm flaps for small wounds (< 4cm), PPP flaps for medium wounds (4- 6cm), ALT perforator flaps for large wounds (6-12 cm), and latissimus dorsi flap with skin graft for massive wounds.
CONCLUSION: Advances in perforator flap surgery have established a place for the ALT flap in lower extremity reconstruction. In North America a high prevalence of obesity results in many patients having an ALT donor site disproportionately thick for many foot and ankle defects. This necessitates risky primary thinning or secondary procedures to achieve aesthetic results. We report success with PPP flaps as a single-stage aesthetic reconstruction in this circumstance. A new algorithm which emphasizes recent advances in microsurgery through use of perforator flaps and super-microsurgery was adopted and utilized. By choosing donor sites that can be closed primarily, iatrogenic morbidity is minimized. By keeping the donor site as close to the traumatic wound as possible, the overall morbidity of treatment is contained to the smallest area possible. Drawbacks include a need for perforator surgery skill, however this is becoming commonplace.