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 pu ...

of the

pelvis The pelvis (plural pelves or pelvises) is the lower part of the trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis, or pelvic skeleton). The ...

Structure

The internal iliac artery supplies the walls and

viscera In biology, an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life, an organ lies between tissue and an organ system. Tissues are formed from same type cells to act together in a f ...

of the

, 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 compose ...

, 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. Th ...

, and about 3 to 4 cm in length.

Course

The internal iliac artery arises at the bifurcation of the

common iliac artery 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 ...

, 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, anterior to the internal iliac vein, anterior to the lumbosacral trunk, and anterior to the piriformis muscle. 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, an externality or external cost is an indirect cost or benefit to an uninvolved third party that arises as an effect of another party ...

, 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 The obturator nerve in human anatomy arises from the ventral divisions of the second, third, and fourth lumbar nerves in the lumbar plexus; the branch from the third is the largest, while that from the second is often very small. Structure The o ...

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 An anastomosis (, plural anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf veins, or streams. Such a connection may be norm ...

Fetal structure

In the

fetus A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal dev ...

, 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 The placenta is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas and waste exchange between the physically separate mate ...

. 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 The sacrum (plural: ''sacra'' or ''sacrums''), in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1S5) between ages 18 and 30. The sacrum situates at the upper, back part o ...

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

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 The iliolumbar artery is the first branch of the posterior trunk of the internal iliac artery. Structure The iliolumbar artery is the first branch of the posterior trunk of the internal iliac artery. It turns upward behind the obturator nerve and ...

(from the posterior division of the internal iliac artery) with the last

lumbar artery The lumbar arteries are arteries located in the lower back or lumbar region. The lumbar arteries are in parallel with the intercostals. They are usually four in number on either side, and arise from the back of the aorta, opposite the bodies of ...

(from the aorta) * the

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

superficial circumflex iliac artery The superficial iliac circumflex artery (or superficial circumflex iliac), the smallest of the cutaneous branches of the femoral artery, arises close to the superficial epigastric artery, and, piercing the fascia lata, runs lateralward, parallel w ...

(from the femoral) * the

lateral sacral arteries The lateral sacral arteries is an artery in the pelvis that arises from the posterior division of the internal iliac artery. It later splits into two smaller branches, a superior and an inferior. Structure The lateral sacral artery is the seco ...

(from the posterior division of the internal iliac artery) with the median sacral artery (from the aorta) * the superior gluteal artery (from the posterior division of the internal iliac artery) with the

(from the femoral) * the inferior gluteal artery (from the anterior division of the internal iliac artery) with the profunda femoris artery (from the femoral) * the obturator artery (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 epig ...

(from the external iliac artery) * the obturator artery (from the anterior division of the internal iliac artery) with the medial circumflex femoral artery (from the profunda femoris artery) * the middle rectal artery (from the anterior division of the internal iliac artery) and the superior rectal artery (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