New Anatomic Landmark for Perforator of Anterolateral Thigh Flap in Preoperative Ultrasonography

ABSTRACT Objectives The midpoint of the thigh is a well‐known anatomic landmark for the perforators of the anterolateral thigh flap. In some cases, dominant perforators can be found around the junction between the tensor fasciae latae and the iliotibial tract, proximal to the midpoint. This study was performed to investigate the utility and anatomical characteristics of these proximal‐type perforators around the junction. Methods Fifty‐two patients who underwent head and neck reconstruction with an anterolateral thigh flap were included. The flap was harvested based on proximal‐type perforators in 28 patients (proximal group) and midpoint‐type perforators in 24 patients (midpoint group). The perforator type, source artery, and pedicle length were compared between the groups. Results A sizable proximal‐type perforator was present in > 70% of patients. In the proximal group, a septocutaneous perforator was common (67.9%); in the midpoint group, however, a musculocutaneous perforator was predominant (87.5%). A total of 71.4% of the proximal perforators arose from the oblique branch of the lateral circumflex femoral artery, whereas all of the midpoint perforators arose from the descending branch. The pedicles were significantly shorter in the proximal group than in the midpoint group. Conclusion The junction between the tensor fasciae latae and the iliotibial tract can serve as a reliable anatomic landmark for the dominant perforator of the anterolateral thigh flap. The proximal‐type perforators differ from the midpoint‐type perforators in that two‐thirds are of the septocutaneous type, 70% are derived from the oblique branch, and the length of the vascular pedicle is shorter. Level of Evidence 3