The gracilis musculocutaneous flap: vascular supply of the muscle and skin components

In reconstructive techniques, the use of the composite gracilis skin flap may be complicated by a total or partial necrosis of the cutaneous paddle. Our study was aimed to describe the vascular anatomy of the gracilis muscle and the related skin, in order to have a better understanding of the skin’s blood supply, and to help in determining a safer cutaneous paddle during transfer. We performed a detailed anatomical description of the gracilis vessels on 32 human cadavers’ thighs. Selective injections of methylene blue and then colored fluid latex were carried out in the principal pedicle of the gracilis, to color and to measure the perforator vessels and the associated cutaneous paddle. The contour and the anatomical situation of the paddles were digitized in order to have precise data and to try to model a standard theoretical skin paddle. The 32 dissections showed that the principal pedicle of the gracilis originated mainly from the adductor artery (26/32), it penetrated into the muscle 92.8 mm (78–114) below the pubis with a small dispersion of the values that assessed a rather reliable parameter of location. Each muscle had 1–6 perforators (at mean 3.78); 80% of these perforators had their exits from the opposite side to the principal pedicle, included within a 60 mm length of muscle. A skin paddle was quite constantly colored (31/32), located over the proximal half of the muscle with a complex design. Its mean dimensions of length and width were 110 (72–158) and 91.4 mm (65–144), respectively. The computerized surface of the paddle was at a mean of 79.5 cm2 (42.4–139.3), and it was significantly correlated to the number of the perforators from the muscle. Our quantitative values concerning the skin paddle related to the perforator arteries may be of significant interest to the surgeon who aims to harvest a composite musculocutaneous gracilis flap, in order to improve its reliability by reducing the risk of cutaneous necrosis.