Femoral triangle

The femoral triangle (a.k.a. Scarpa’s triangle) is a triangular space located in the upper thigh beneath the inguinal ligament. The subfascial space has distinct boundaries, a floor, and a roof, and contains important structures.

Boundaries: The femoral triangle is bordered by the adductor longus muscle medially, sartorius muscle laterally, and the inguinal ligament forming the base of the triangle. The apex, formed by the intersection of the adductor longus and sartorius, points downward. It extends into the adductor canal, which leads the contents of the adductor canal (i.e. the femoral vessels) into the popliteal fossa through an opening in the adductor magnus muscle.

Floor: The floor of the femoral triangle consists of several muscles from lateral to medial, including iliacus and psoas major (collectively known as iliopsoas), pectineus, and adductor longus muscles.

Roof: The roof of the femoral triangle, from superficial to deep, is composed of skin, superficial fascia, and deep fascia (fascia lata).

Contents: From lateral to medial, the femoral triangle contains the femoral nerve, femoral artery, femoral vein, and femoral canal. The femoral canal houses lymphatics. The femoral artery, vein, and femoral canal are enclosed by a fascial sleeve called the femoral sheath, while the femoral nerve lies outside the femoral sheath and lateral to it. It is important to note that the femoral canal represents a potential weak point in the lower abdomen and can lead to the development of femoral hernias.