Iliac veins

The vessels that transport deoxygenated blood from the lower limbs and pelvis back to the heart.

A set of major veins located in the pelvis that contribute to the systemic circulation of blood. The iliac veins consist of the common iliac veins, which are formed by the union of the internal and external iliac veins. These veins play a critical role in draining blood from the lower extremities and pelvic region, ultimately directing it back to the right atrium of the heart.

Terminologia Anatomica

vena-iliaca

System

Circulatory system

Function

The primary function of the iliac veins is to facilitate the return of deoxygenated blood from the lower parts of the body to the heart. This process is essential for maintaining circulation and ensuring that blood can be oxygenated in the lungs. As the lower limbs undergo various activities such as walking or running, muscles contract, which aids in pushing the venous blood upwards against the force of gravity, a phenomenon known as venous return. Additionally, the valves present within the iliac veins help to prevent backflow, ensuring that blood travels in one direction towards the heart. The efficiency of the iliac veins is crucial for overall circulatory health; any obstruction or dysfunction can lead to complications such as deep vein thrombosis.

Location

The iliac veins are situated in the pelvis, specifically near the sacrum and the lower abdominal cavity. Each common iliac vein is a continuation of the respective internal and external iliac veins. The internal iliac vein drains blood from the pelvic organs, while the external iliac vein collects blood from the lower limbs. The right and left common iliac veins converge at the level of the fifth lumbar vertebra, where they form the inferior vena cava, the largest vein in the human body, which then ascends to the heart. Their anatomical positioning is critical for efficient blood flow, as they are located in proximity to major arteries and veins that serve the legs and pelvis.

Did You Know?

The iliac veins can be affected by various conditions, including venous insufficiency, which may result in swelling and discomfort in the legs.
During pregnancy, the growing uterus can compress the iliac veins, potentially leading to increased risk of blood clots.
The diameter of the iliac veins can vary significantly based on factors such as body mass index and physical fitness.
Iliac vein thrombosis can occur, which is when a blood clot forms in the vein, leading to serious complications if not treated promptly.