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

artery An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...

of the

pelvis The pelvis (: pelves or pelvises) is the lower part of an Anatomy, anatomical Trunk (anatomy), trunk, between the human abdomen, abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also c ...

Structure

The internal iliac artery supplies the walls and

viscera In a multicellular organism, 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 a ...

of the

, the

buttock The buttocks (: 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 of a laye ...

, the reproductive organs, 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 Artery, 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 arter ...

, 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 ...

, opposite the lumbosacral articulation, and, passing downward to the upper margin of the

greater sciatic foramen The greater sciatic foramen is an opening (:wikt:foramen, foramen) in the posterior human pelvis. It is formed by the sacrotuberous ligament, sacrotuberous and sacrospinous ligaments. The piriformis muscle passes through the foramen and occupies ...

, divides into two large trunks, an anterior and a posterior. It is posterior to 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 ...

, anterior to 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 ...

, anterior to the lumbosacral trunk, and anterior to the

piriformis muscle The piriformis muscle () is a flat, pyramidally-shaped muscle in the buttock, 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, ...

. Near its origin, it is medial to the external iliac vein, which lies between it and the

psoas major muscle 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 equ ...

. It is above the obturator nerve.

Branches

The arrangement of branches of the internal iliac artery is extremely 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. In recent years the development of techniques like prostate artery embolisation and angiografy led to an increased understanding of the prostate vascularisation. Regarding the arterial supply M. de Assis et al. has suggested an anatomic classification for the origin of the inferior vesical artery The following are the branches of internal iliac artery:

Anastamoses

In individuals who are biological females, the ovarian artery (a branch of the abdominal aorta) and uterine arteries form

anastomoses An anastomosis (, : 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, leaf veins, or streams. Such a connection may be ...

Fetal structure

In the

fetus A fetus or foetus (; : fetuses, foetuses, rarely feti or foeti) is the unborn offspring of a viviparous animal that develops from an embryo. Following the embryonic development, embryonic stage, the fetal stage of development takes place. Pren ...

, the internal iliac artery is twice as large as the external iliac, and is the direct continuation of the common iliac. It ascends along the side of the

bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the bladder is a distens ...

, 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 Placentalia, 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 i ...

, where they coil around the umbilical vein, and ultimately ramify in the

placenta The placenta (: placentas or placentae) 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 ...

. 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, 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, and is covered by the medial umbilical folds (''plica ...

(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 (: sacra or sacrums), in human anatomy, is a 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 of the pelvic cavity, ...

and the upper border of the

. 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 (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 terminal branch of the posterior division of the internal iliac artery. It exits the pelvis through the greater sciatic foramen before splitting into a superficial branch and a deep branch. Structure Origin Th ...

(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) is a terminal branch of the anterior trunk of the internal iliac artery. It exits the pelvis through the greater sciatic foramen. It is distributed chiefly to the buttock and the back of the thigh. Ana ...

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

profunda femoris artery The deep femoral artery also known as the deep artery of the thigh, or profunda femoris artery, is a large branch of the femoral artery. It travels more deeply ("profoundly") than the rest of the femoral artery. It gives rise to the lateral ci ...

(from the femoral) * the obturator artery (from the anterior division of the internal iliac artery) with the

inferior epigastric artery In human anatomy, the inferior epigastric artery is an artery that arises from the external iliac artery. It is accompanied by the inferior epigastric vein; inferiorly, these two inferior epigastric vessels together travel within the lateral um ...

(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 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 ...

(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 ut ...

(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 A computed tomography scan (CT scan), formerly called computed axial tomography scan (CAT scan), is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers or ...

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