Comprehensive analysis of the anterolateral thigh flap vascular anatomy

The anterolateral thigh (ALT) flap has become a frequently used free flap for head and neck reconstruction. Widespread use has been based on literature of ALT flap thickness performed primarily in Asian populations. To our knowledge, to date there has not been a comprehensive analysis of the anthropomorphic parameters of this flap in the Western population, in which it is often much thicker, thereby potentially limiting its utility.

Computed tomographic angiograms of 106 patients were assessed, yielding 196 lower-extremity scans examined for volumetric characteristics and vascular anatomical variations.

Perforator vessels were located in 88.8% of scans, and most commonly located were a hybrid musculoseptocutaneous vessel (52.3%) followed by septocutaneous (33.9%) and musculocutaneous (13.8%) vessels. The midpoint perforator was located within ±2% of the midpoint of the total thigh length in only 47% of legs. The proximal and distal perforators were located 52.7 and 58.6 mm from the midpoint, respectively. Subcutaneous fat thickness differed significantly by sex, with mean male and female thicknesses of 9.9 mm and 19.9 mm (P < .001), respectively. Thickness increased with increasing body mass index, especially in women.

This study used computed tomographic angiography to characterize the ALT flap vasculature and thickness, providing a degree of predictability to these 2 highly variable flap characteristics.