The femoral triangle is a superficial triangular space located on the anterior aspect of the thigh just inferior to the inguinal ligament. The purpose of this blog is to explain the femoral triangle and its boundaries, the floor, the roof, and its contents.
The boundaries of the femoral triangle include the lateral and medial borders, and the base. The lateral border is formed by the medial border of the Sartorius Muscle. The medial border is formed by the medial border of the Adductor Longus Muscle, and the base is formed by the inguinal ligament.
The floor of the triangle is formed by the Iliacus, the psoas major, the pectineus, and the adductor longus muscles. The roof of the femoral triangle is covered by skin, as well as superficial and deep fascia. The femoral triangle contains three important structures, from lateral to medial: the femoral Nerve, femoral Artery, and femoral Vein—which contains the Deep Inguinal Lymph nodes. You will NAVIgate the femoral triangle from lateral to medial.
The femoral triangle also contains the femoral sheath, which is a funnel shaped sleeve of fascia enclosing the upper 4cm of the femoral vessels. The femoral nerve is the most important nerve within the triangle; however, it is not the only nerve. The femoral nerve lies within the groove between the Iliacus and the Psoas Major muscles. There are two other nerves located within the femoral triangle, the Lateral Cutaneous Nerve of the Thigh and the Femoral Branch of the Genitofemoral Nerve. The Lateral Cutaneous Nerve of the Thigh crosses the lateral corner of the triangle and supplies the skin on the lateral part of the thigh. The Femoral Branch of the Genitofemoral Nerve runs in the lateral compartment of the femoral sheath and supplies the majority of the skin over the femoral triangle.The neurovascular bundle is medial to the Sartorius muscle. Therefore, in the anterior approach to the hip, it is always safe to go lateral to the Sartorius muscle in order to avoid the important structures within the femoral triangle. It is important to remember when performing this approach to avoid the lateral cutaneous nerve of the thigh.
The femoral sheath is a fascial sheath that contains the femoral artery, vein, and canal. The anterior portion of the femoral sheath is formed by a downward extension of the fascia transversalis. The posterior portion is formed by the iliac fascia. The femoral sheath is divided into three compartments: lateral, intermediate, and medial. The lateral compartment contains the femoral artery and the intermediate compartment contains the femoral vein. The medial compartment is referred to as the femoral canal and contains the lymphatic tissue. The base of the femoral canal is formed by the femoral ring. A femoral hernia occurs when a part of the intestine protrudes through a weak femoral ring into the femoral canal.
