The external iliac veins are large

vein Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and feta ...

s that connect the

femoral vein In the human body, the femoral vein is the vein that accompanies the femoral artery in the femoral sheath. It is a deep vein that begins at the adductor hiatus (an opening in the adductor magnus muscle) as the continuation of the popliteal v ...

s to the

common iliac vein In human anatomy, the common iliac veins are formed by the external iliac veins and internal iliac veins. The left and right common iliac veins come together in the abdomen at the level of the lumbar vertebrae, fifth lumbar vertebra, forming the ...

s. Their origin is at the inferior margin of the

inguinal ligament The inguinal ligament (), also known as Poupart's ligament or groin ligament, is a band running from the pubic tubercle to the anterior superior iliac spine. It forms the base of the inguinal canal through which an indirect inguinal hernia may ...

s and they terminate when they join the

internal iliac vein The internal iliac vein (hypogastric vein) begins near the upper part of the greater sciatic foramen, passes upward behind and slightly medial to the internal iliac artery and, at the brim of the pelvis, joins with the external iliac vein to for ...

s (to form the

s). Both external iliac veins are accompanied along their course by external iliac arteries.

Structure

A continuation of the

, the external iliac vein starts at the level of the inguinal ligament. It runs beside its corresponding artery and along the brim of the

lesser pelvis The pelvic cavity is a body cavity that is bounded by the bones of the pelvis. Its oblique roof is the pelvic inlet (the superior opening of the pelvis). Its lower boundary is the pelvic floor. The pelvic cavity primarily contains the reproduc ...

to unite with the internal iliac vein anterior to the

sacroiliac joint The sacroiliac joint or SI joint (SIJ) is the joint between the sacrum and the ilium bones of the pelvis, which are connected by strong ligaments. In humans, the sacrum supports the spine and is supported in turn by an ilium on each side. The ...

where it forms the common iliac vein. The left external iliac vein remains medial to the artery along its whole path. The right external iliac vein is medial to the artery, but as it ascends, it runs posterior to it. The external iliac vein is crossed by the

ureter The ureters are tubes composed of smooth muscle that transport urine from the kidneys to the urinary bladder. In an adult human, the ureters typically measure 20 to 30 centimeters in length and about 3 to 4 millimeters in diameter. They are lin ...

and internal iliac artery which both extend towards the middle. In males it is crossed by the

vas deferens The vas deferens (: vasa deferentia), ductus deferens (: ductūs deferentes), or sperm duct is part of the male reproductive system of many vertebrates. In mammals, spermatozoa are produced in the seminiferous tubules and flow into the epididyma ...

and in females the round ligament and ovarian vessels cross it.

Psoas major The psoas major ( or ; from ) is a long fusiform muscle located in the lateral lumbar region between the vertebral column and the brim of the lesser pelvis. It joins the iliacus muscle to form the iliopsoas. In other animals, this muscle is e ...

lies to its side, except where the artery intervenes. The external iliac vein may have one valve, but often has no valves. In addition to pubic veins, the main tributaries of the external iliac veins are the inferior epigastric veins and the

deep circumflex iliac vein The deep circumflex iliac vein is formed by the union of the venae comitantes of the deep iliac circumflex artery. It drains venous blood from the walls of the iliac fossa. It empties into the external iliac vein about 2 cm superior to the i ...

Clinical significance and history

In 1967, Cockett noted anatomical variations which predisposed to compression of the external iliac vein, amongst other veins. Although less common than May-Thurner syndrome, it is being progressively documented due to modern imaging methods. Compression of the left external iliac vein by the right common iliac artery or left hypogastric artery can occur as it crosses over the vein into the pelvis. The right external iliac vein can similarly be compressed. Such compressions may contribute to

deep vein thrombosis Deep vein thrombosis (DVT) is a type of venous thrombosis involving the formation of a blood clot in a deep vein, most commonly in the legs or pelvis. A minority of DVTs occur in the arms. Symptoms can include pain, swelling, redness, and enl ...

. Failure to develop or

agenesis In medicine, agenesis () refers to the failure of an organ to develop during embryonic growth and development due to the absence of primordial tissue. Many forms of agenesis are referred to by individual names, depending on the organ affected: ...

of the external iliac vein has been described in association with Klippel–Trenaunay syndrome.

Additional images

File:Gray480.png, Diagram showing completion of development of the parietal veins. File:Gray539.png, The arteries of the male pelvis. File:Gray585.png, The veins of the right half of the male pelvis. File:Gray1146.png, The spermatic cord in the inguinal canal. File:Slide10BLA.JPG, External iliac vein. Deep dissection. Serial cross section.

References

External links

* () {{Authority control Veins of the torso Angiology