Inguinal ligament

The inguinal ligament, also known as the Poupart's ligament, is located in the anterior aspect of the pelvis on either side of the body. 

It extends from the anterior superior iliac spine to the pubic tubercle

The ligament is formed by the inferior border of the aponeurosis of the external abdominal oblique muscle as it attaches to the same structures where the ligament stretches.

The medial end of the inguinal ligament and its fibers form the lacunar ligament (also known as the Gimbernat ligament) extending from the inguinal ligament to the pubic bone, while the extension of the lacunar ligament from the pubic tubercle to the pecten pubis located on the superior ramus of the pubic bone is known as the pectineal ligament (ligament of Cooper).

The lateral one-third of the inguinal ligament serves an origin site for the transversus abdominis muscle. The lateral two-thirds of the ligament is an origin for the internal abdominal oblique muscle.

Inferiorly the inguinal ligament is connected to the fascia lata of the thigh.

The inguinal ligament not only anchors the aponeurosis of the external oblique muscle and is an origin site for the mentioned muscles, but it also protects various structures entering and exiting the pelvic cavity.

The midpoint of the inguinal ligament is an essential landmark in surgery and medicine as it is the site where the external iliac artery continues as the femoral artery once it gets outside of the pelvic cavity. It is the only site where the palpation of the femoral artery is possible. 

Also, the femoral vein becomes the external iliac vein when it crosses the inguinal ligament, exiting the pelvic cavity and entering the lower limb.

The inguinal ligament participates in forming the base of the femoral triangle, and the medial half of the superior surface of the inguinal ligament forms the floor of the inguinal canal.



Inguinal canal

The inguinal canal is a passage located superior to the inguinal ligament, going parallel to it. The canal connects the abdominal cavity with the external genitalia and structures located in the groin. 

Each end of the inguinal canal contains an opening. The deep inguinal ring (internal) represents the inner opening of the canal located in the midpoint of the ligament, while the superficial inguinal ring (external) is the outer opening located around the pubic tubercle.

The inguinal canal contains the spermatic cord (only in males), round ligament of the uterus (only in females), ilioinguinal nerve, genital branch of the genitofemoral nerve.