The internal iliac artery (formerly known as the hypogastric artery) is the main

artery An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the p ...

of the pelvis.

Structure

The internal iliac artery supplies the walls and viscera of the pelvis, the

buttock The buttocks (singular: buttock) are two rounded portions of the exterior anatomy of most mammals, located on the posterior of the pelvic region. In humans, the buttocks are located between the lower back and the perineum. They are composed ...

, the

reproductive organs A sex organ (or reproductive organ) is any part of an animal or plant that is involved in sexual reproduction. The reproductive organs together constitute the reproductive system. In animals, the testis in the male, and the ovary in the female, a ...

, and the medial compartment of the thigh. The vesicular branches of the internal iliac arteries supply the bladder. It is a short, thick vessel, smaller than the

external iliac artery The external iliac arteries are two major arteries which bifurcate off the common iliac arteries anterior to the sacroiliac joint of the pelvis. Structure The external iliac artery arises from the bifurcation of the common iliac artery. They ...

, and about 3 to 4 cm in length.

Course

The internal iliac artery arises at the bifurcation of the common iliac artery, opposite the lumbosacral articulation, and, passing downward to the upper margin of the greater sciatic foramen, divides into two large trunks, an anterior and a posterior. It is posterior to the

ureter The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional ep ...

, anterior to the internal iliac vein, anterior to the lumbosacral trunk, and anterior to the

piriformis muscle The piriformis muscle () is a flat, pyramidally-shaped muscle in the gluteal region of the lower limbs. It is one of the six muscles in the lateral rotator group. The piriformis muscle has its origin upon the front surface of the sacrum, and ins ...

. Near its origin, it is medial to the

external iliac vein External may refer to: * External (mathematics), a concept in abstract algebra * Externality, in economics, the cost or benefit that affects a party who did not choose to incur that cost or benefit * Externals The Externals are a group of ...

, which lies between it and the

psoas major muscle The psoas major ( or ; from grc, ψόᾱ, psóā, muscles of the loins) 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 il ...

. It is above the obturator nerve.

Branches

The arrangement of branches of the internal iliac artery is variable. Typically, the artery divides into an anterior division and a posterior division, with the posterior division giving rise to the superior gluteal, iliolumbar, and lateral sacral arteries. The rest usually arise from the anterior division. Because it is variable, an artery may not be a direct branch, but instead might arise off a direct branch. The following are the branches of internal iliac artery:

Anastamoses

In individuals

assigned female at birth Sex assignment (sometimes known as gender assignment) is the discernment of an infant's sex at or before birth. A relative, midwife, nurse or physician inspects the external genitalia when the baby is delivered and, in more than 99.95% of bir ...

, the ovarian artery (a branch of the abdominal aorta) and uterine arteries form an anastomoses. Internal iliac branches

Fetal structure

In the fetus, the internal iliac artery is twice as large as the external iliac, and is the direct continuation of the

common iliac The common iliac artery is a large artery of the abdomen paired on each side. It originates from the aortic bifurcation at the level of the 4th lumbar vertebra. It ends in front of the sacroiliac joint, one on either side, and each bifurcates in ...

. It ascends along the side of the

bladder The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine en ...

, and runs upward on the back of the anterior wall of the abdomen to the umbilicus, converging toward its fellow of the opposite side. Having passed through the umbilical opening, the two arteries, now termed ''umbilical'', enter the

umbilical cord In placental mammals, the umbilical cord (also called the navel string, birth cord or ''funiculus umbilicalis'') is a conduit between the developing embryo or fetus and the placenta. During prenatal development, the umbilical cord is physiologi ...

, where they coil around the umbilical vein, and ultimately ramify in the placenta. At birth, when the placental circulation ceases, the pelvic portion only of the umbilical artery remains patent gives rise to the superior vesical artery (or arteries) of the adult; the remainder of the vessel is converted into a solid fibrous cord, the

medial umbilical ligament The medial umbilical ligament (or cord of umbilical artery, or obliterated umbilical artery) is a paired structure found in human anatomy. It is on the deep surface of the anterior abdominal wall In anatomy, the abdominal wall represents the bo ...

(otherwise known as the obliterated hypogastric artery) which extends from the pelvis to the umbilicus.

Variation

In two-thirds of a large number of cases, the length of the internal iliac varied between 2.25 and 3.4 cm.; in the remaining third it was more frequently longer than shorter, the maximum length being about 7 cm. the minimum about 1 cm. The lengths of the common iliac and internal iliac arteries bear an inverse proportion to each other, the internal iliac artery being long when the common iliac is short, and vice versa. The place of division of the internal iliac artery varies between the upper margin of the sacrum and the upper border of the greater sciatic foramen. The right and left hypogastric arteries in a series of cases often differed in length, but neither seemed constantly to exceed the other.

Common branching variations

File:Variation 1 of internal iliac artery branching.svg, The typical exampleEssential Clinical Anatomy. K.L. Moore & A.M. Agur. Lippincott, 2 ed. 2002. Page 224 File:Variation 2 of internal iliac artery branching.svg File:Variation 3 of internal iliac artery branching.svg File:Variation 4 of internal iliac artery branching.svg File:Variation 5 of internal iliac artery branching.svg

Collateral circulation

The circulation after ligature of the internal iliac artery is carried on by the anastomoses of:Arisudhan Anantharachagan, Sarris, I. and Ugwumadu, A. (2011). Revision Notes for the MRCOG Part 1. Oxford Oxford University Press -07-01. pages 90-91 * the iliolumbar artery (from the posterior division of the internal iliac artery) with the last lumbar artery (from the aorta) * the iliolumbar artery (from the posterior division of the internal iliac artery) with the superficial circumflex iliac artery (from the femoral) * the lateral sacral arteries (from the posterior division of the internal iliac artery) with the median sacral artery (from the aorta) * the

superior gluteal artery The superior gluteal artery is the largest and final branch of the internal iliac artery. It is the continuation of the posterior division of that vessel. It is a short artery which runs backward between the lumbosacral trunk and the first sacral ...

(from the posterior division of the internal iliac artery) with the superficial circumflex iliac artery (from the femoral) * the

inferior gluteal artery The inferior gluteal artery (sciatic artery), the smaller of the two terminal branches of the anterior trunk of the internal iliac artery, is distributed chiefly to the buttock and back of the thigh. It passes down on the sacral plexus of nerves a ...

(from the anterior division of the internal iliac artery) with the

profunda femoris artery The deep artery of the thigh, (profunda femoris artery or deep femoral artery) is a large branch of the femoral artery. It travels more deeply (posteriorly) than the rest of the femoral artery. Structure The deep artery of the thigh branches of ...

(from the femoral) * the

obturator artery The obturator artery is a branch of the internal iliac artery that passes antero-inferiorly (forwards and downwards) on the lateral wall of the pelvis, to the upper part of the obturator foramen, and, escaping from the pelvic cavity through the o ...

(from the anterior division of the internal iliac artery) with the

inferior epigastric artery In human anatomy, inferior epigastric artery refers to the artery that arises from the external iliac artery. It anastomoses with the superior epigastric artery. Along its course, it is accompanied by a similarly named vein, the inferior epigas ...

(from the external iliac artery) * the

(from the anterior division of the internal iliac artery) with the

medial circumflex femoral artery The medial circumflex femoral artery (internal circumflex artery, medial femoral circumflex artery) is an artery in the upper thigh that arises from the profunda femoris artery''.'' Damage to the artery following a femoral neck fracture may lead ...

(from the profunda femoris artery) * the

middle rectal artery The middle rectal artery is an artery in the pelvis that supplies blood to the rectum. Structure The middle rectal artery usually arises from the internal iliac artery. It is distributed to the rectum above the pectinate line. It anastomoses wi ...

(from the anterior division of the internal iliac artery) and the

superior rectal artery The superior rectal artery (superior hemorrhoidal artery) is an artery that descends into the pelvis to supply blood to the rectum. Structure The superior rectal artery is the continuation of the inferior mesenteric artery. It descends into the p ...

(a branch of the inferior mesenteric artery) * the

uterine arteries The uterine artery is an artery that supplies blood to the uterus in females. Structure The uterine artery usually arises from the anterior division of the internal iliac artery. It travels to the uterus, crossing the ureter anteriorly, to the ute ...

(from the anterior division of the internal iliac artery) and the ovarian arteries (from the aorta)

Additional images

File:Volume rendered CT scan of abdominal and pelvic blood vessels (smaller).gif, Volume rendered CT scan of abdominal and pelvic blood vessels. File:Gray539.png, Bifurcation of the aorta and the right iliac arteries - side view. File:Gray829.png, Dissection of side wall of pelvis showing sacral and pudendal plexuses. File:Gray837.png, Sacral plexus of the right side. File:Gray1036.png, Posterior view of the anterior abdominal wall in its lower half. The peritoneum is in place, and the various cords are shining through. File:Gray1121.png, Posterior abdominal wall, after removal of the peritoneum, showing kidneys, suprarenal capsules, and great vessels. File:Gray1170.png, The arteries of the internal organs of generation of the female, seen from behind. File:Male hypogastric artery.jpg, Male hypogastric artery File:Hypogastric artery.jpg, Female hypogastric artery File:Slide1ewew.JPG, Lumbar and sacral plexus. Deep dissection. Anterior view. File:Slide2ewew.JPG, Lumbar and sacral plexus. Deep dissection. Anterior view. File:Slide3ewew.JPG, Lumbar and sacral plexus. Deep dissection. Anterior view. File:Slide2ERVA.JPG, Pelvic contents: male. Superior view. Deep dissection. File:Ureters and hypogastric vessels.JPG, Hypogastric vessels File:Internal iliac arteries.jpg, Internal iliac arteries File:Slide1erer.JPG, Lumbar and sacral plexus. Deep dissection.Anterior view.

References

External links

* * *
Illustration at wiseowl.com

"Variation in Origin of the Parietal Branches of internal iliac artery based on a study of 169 Specimens (108 males and 61 females)." at anatomyatlases.org
* * () {{Authority control Arteries of the abdomen

Structure

Course

Branches

Anastamoses

Fetal structure

Variation

Common branching variations

Collateral circulation

Additional images

See also

References

External links