Beneath the perforators: Unravelling fascia lata intrinsic vascular architecture using microfocus X-ray computed...

The fascia lata (FL), a dense connective tissue enveloping the deep structures of the thigh, has served as an avascular scaffold for decades in reconstructive surgeries, but never as a standalone vascularized flap, because its vasculature is only described by perforating vessels coming from the lateral circumflex femoral artery without specific intrinsic vasculature. However, the demand for vascularized tissue replacements requires a thorough understanding of this inherent vascularization. Based on the anterolateral thigh (ALT) flap knowledge, this study explores the detailed quantitative vascular architecture of the FL, from the perspective of using it as a standalone vascularized flap.

High-resolution microfocus X-ray computed tomography (microCT) of Angiofil-latex injected flaps allowed us to study the specific fascial distribution of perforators. Dissections of 11 fresh-frozen lower limbs identified the main perforating arterioles. The intrinsic vascular network within the FL tissue was then analyzed using microCT.

The study confirmed an average of 2.5 ± 0.5 main perforating trunks giving rise to 5.6 ± 2.9 perforating arterioles per thigh. Notably, microCT revealed a distinct intrinsic vascular network within the FL tissue, with tiny arterioles of 55.39 ± 28.47 µm radius and a volumetric density of 33,347,960 ± 23,243,879 µm³ /mm². This intrinsic vasculature exhibited a high density of bifurcations (branching nodes=1.36 ± 2.26/mm²), demonstrating its potential use as a vascularized flap.

This study unveils the intrinsic vascularization of the FL, supporting its utility as a mega-thin vascularized flap in reconstructive surgery. Based on this vascular carrier, these findings also open new applications for tissue engineering and personalized medicine, toward an improvement of surgical outcomes and patient recovery.