The free sartorius flap: clinical cases and anatomical study

The thigh is a rich source of tissue for free flap harvest. The anterolateral thigh and gracilis flaps are most commonly used. The sartorius flap is an easily harvested flap that can be raised with the leg in the anatomically extended position without rotation. The cutaneous landmarks are readily identified and so the relevant perforators can be quickly found. Pedicle dissection is quick and easy, allowing the flap to be raised in a short time. We report our experience of using this flap both as a free muscle-only flap and as a free fasciocutaneous perforator flap for soft-tissue reconstruction in the lower limb. An anatomical study was also carried out to examine the vascular anatomy of the sartorius muscle flap and the cutaneous perforator flap. Twenty limbs from soft fixed adult cadavers were dissected and the position, length, diameter and cutaneous extension of all segmental pedicles, from the anterior superior iliac spine (ASIS) to the medial femoral condyle, were measured. Fourteen out of 20 (70%) sartorius muscles had at least one musculocutaneous perforator and, of these muscles, 13 (93%) had at least one musculocutaneous perforator that was found at 20±3cm from the ASIS. The free sartorius flap is a useful addition to flap choice from the thigh and carries a predictable cutaneous perforator in the majority of cases, allowing a fasciocutaneous perforator flap to be quickly and reliably raised with minimal donor-site morbidity.