Background: This study aimed to delineate and compare the hot spots and three-dimensional vascular territories of dominant profunda artery perforators in the posterior thigh region, and modifications in flap design are discussed.

Methods: Twenty-nine posterior thigh flaps were raised in fresh cadaveric specimens, and profunda artery perforators were documented. Dominant perforators were injected with iodinated contrast to assess perforasomes using computed tomographic angiography. Analysis with three-dimensional rendering and volume calculations of perfusion patterns was performed.

Results: In total, 316 perforators were mapped and 33 perforators were injected for analysis. The hot spot for dominant perforators was the proximal medial quadrant, 5 to 10 cm from the inferior gluteal crease, with two smaller hot spots in the upper lateral and distal posterior midline. Although 69 percent were musculocutaneous, distal perforators were predominantly septocutaneous in the posterior midline, 5 to 8 cm from the popliteal crease. Proximal perforators were classified into first (most proximal) and second perforators, and their median perforasome was 233 and 286.4 cm2, respectively (p = 0.86). There were no significant differences between proximal and distal perforators in perforasome surface areas, percentage areas perfused, and perforasome volumes. Large linking vessel networks were attributed to a broader perforasome and greater overlap between adjacent or distal perforators.

Conclusions: Dominant linking vessels and recurrent flow through the subdermal plexus contribute to the robust vascular supply of profunda artery perforator flaps. Posterior thigh region perforator hot spots and their perfusion characteristics can inform the potential limits, orientation, and modifications of flap or skin paddle designs.