The
internal iliac artery (formerly known as the
hypogastric artery) is the main
arteryArteries are blood vessels that carry blood away from the heart. All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood.The circulatory system is extremely important for sustaining life...
of the
pelvisIn human anatomy, the pelvis is the part of the trunk inferioposterior to the abdomen in the transition area between the trunk and the lower limbs...
.
The internal iliac artery supplies the walls and viscera of the
pelvisIn human anatomy, the pelvis is the part of the trunk inferioposterior to the abdomen in the transition area between the trunk and the lower limbs...
, the buttock, the reproductive organs, and the medial compartment of the
thighIn humans the thigh is the area between the pelvis and the knee. Anatomically, it is part of the lower limb.The single bone in the thigh is called the femur...
.
It is a short, thick vessel, smaller than the
external iliac arteryThe external iliac artery is a large artery in the pelvic region that carries blood to the lower limb.The external iliac artery is a paired artery, meaning there is one on each side of the body: a right external iliac artery and left external iliac artery.The external iliac artery is accompanied by...
, and about 3 to 4 cm in length.
It arises at the bifurcation of the
common iliac arteryThe common iliac arteries are two large arteries, about 4cm long in adults but more than a centimetre in diameter, that originate from the aortic bifurcation. The arteries run inferolaterally, along the medial border of the psoas muscles to the pelvic brim, where they bifurcate into the external...
, opposite the lumbosacral articulation (L5/S1 intervertebral disc), and, passing downward to the upper margin of the
greater sciatic foramen-Boundaries:It is bounded as follows:* anterolaterally by the greater sciatic notch of the illium* posteromedially by the sacrotuberous ligament* inferiorly by the sacrospinous ligament and the ischial spine* superiorly by the anterior sacroilliac ligament...
, divides into two large trunks, an anterior and a posterior.
The following are relations of the artery at various points: it is posterior to the
ureterIn human anatomy, the ureters are muscular ducts that propel urine from the kidneys to the urinary bladder. In the adult, the ureters are usually long....
, anterior to the
internal iliac veinThe internal iliac vein begins near the upper part of the greater sciatic foramen, passes upward behind and slightly medial to the hypogastric artery and, at the brim of the pelvis, joins with the external iliac to form the common iliac vein.-Tributaries:With the exception of the fetal umbilical...
, the
lumbosacral trunkThe lumbosacral trunk is nervous tissue that connects the lumbar plexus with the sacral plexus.-Structure:The lumbosacral trunk comprises the whole of the anterior division of the fifth and a part of that of the fourth lumbar nerve; it appears at the medial margin of the psoas major and runs...
, and the
piriformis muscleThe piriformis is a muscle in the gluteal region of the lower limb.-Origin and insertion:It originates from the anterior part of the sacrum, the part of the spine in the gluteal region, and from the superior margin of the greater sciatic notch...
; near its origin, it is medial to the
external iliac veinThe external iliac veins are large veins that connect the femoral veins to the common iliac veins. Their origin is at the inferior margin of the inguinal ligaments and they terminate when they join the internal iliac veins ....
, which lies between it and the
psoas major muscleThe psoas major is a long fusiform muscle placed on the side of the lumbar region of the vertebral column and brim of the lesser pelvis. It joins the iliacus muscle to form the iliopsoas. In less than 50 percent of subjects the psoas major is accompanied by the psoas minor.-Origin:The psoas major...
; it is above the
obturator nerveThe obturator nerve arises from the ventral divisions of the second, third, and fourth lumbar nerves; the branch from the third is the largest, while that from the second is often very small.-Path:...
.
The exact arrangement of branches of the internal iliac artery is variable.
The
internal iliac artery (formerly known as the
hypogastric artery) is the main
arteryArteries are blood vessels that carry blood away from the heart. All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood.The circulatory system is extremely important for sustaining life...
of the
pelvisIn human anatomy, the pelvis is the part of the trunk inferioposterior to the abdomen in the transition area between the trunk and the lower limbs...
.
Structure
The internal iliac artery supplies the walls and viscera of the
pelvisIn human anatomy, the pelvis is the part of the trunk inferioposterior to the abdomen in the transition area between the trunk and the lower limbs...
, the buttock, the reproductive organs, and the medial compartment of the
thighIn humans the thigh is the area between the pelvis and the knee. Anatomically, it is part of the lower limb.The single bone in the thigh is called the femur...
.
It is a short, thick vessel, smaller than the
external iliac arteryThe external iliac artery is a large artery in the pelvic region that carries blood to the lower limb.The external iliac artery is a paired artery, meaning there is one on each side of the body: a right external iliac artery and left external iliac artery.The external iliac artery is accompanied by...
, and about 3 to 4 cm in length.
Course
It arises at the bifurcation of the
common iliac arteryThe common iliac arteries are two large arteries, about 4cm long in adults but more than a centimetre in diameter, that originate from the aortic bifurcation. The arteries run inferolaterally, along the medial border of the psoas muscles to the pelvic brim, where they bifurcate into the external...
, opposite the lumbosacral articulation (L5/S1 intervertebral disc), and, passing downward to the upper margin of the
greater sciatic foramen-Boundaries:It is bounded as follows:* anterolaterally by the greater sciatic notch of the illium* posteromedially by the sacrotuberous ligament* inferiorly by the sacrospinous ligament and the ischial spine* superiorly by the anterior sacroilliac ligament...
, divides into two large trunks, an anterior and a posterior.
The following are relations of the artery at various points: it is posterior to the
ureterIn human anatomy, the ureters are muscular ducts that propel urine from the kidneys to the urinary bladder. In the adult, the ureters are usually long....
, anterior to the
internal iliac veinThe internal iliac vein begins near the upper part of the greater sciatic foramen, passes upward behind and slightly medial to the hypogastric artery and, at the brim of the pelvis, joins with the external iliac to form the common iliac vein.-Tributaries:With the exception of the fetal umbilical...
, the
lumbosacral trunkThe lumbosacral trunk is nervous tissue that connects the lumbar plexus with the sacral plexus.-Structure:The lumbosacral trunk comprises the whole of the anterior division of the fifth and a part of that of the fourth lumbar nerve; it appears at the medial margin of the psoas major and runs...
, and the
piriformis muscleThe piriformis is a muscle in the gluteal region of the lower limb.-Origin and insertion:It originates from the anterior part of the sacrum, the part of the spine in the gluteal region, and from the superior margin of the greater sciatic notch...
; near its origin, it is medial to the
external iliac veinThe external iliac veins are large veins that connect the femoral veins to the common iliac veins. Their origin is at the inferior margin of the inguinal ligaments and they terminate when they join the internal iliac veins ....
, which lies between it and the
psoas major muscleThe psoas major is a long fusiform muscle placed on the side of the lumbar region of the vertebral column and brim of the lesser pelvis. It joins the iliacus muscle to form the iliopsoas. In less than 50 percent of subjects the psoas major is accompanied by the psoas minor.-Origin:The psoas major...
; it is above the
obturator nerveThe obturator nerve arises from the ventral divisions of the second, third, and fourth lumbar nerves; the branch from the third is the largest, while that from the second is often very small.-Path:...
.
Branches
The exact arrangement of branches of the internal iliac artery is variable. Generally, 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.
The following are the branches of internal iliac artery. Because it is variable, a listed artery may not be a direct branch, but instead might arise off a direct branch.
| Division |
Branch |
Sub-branches |
To/through
>-
| Posterior |
Iliolumbar artery -Course:The iliolumbar artery turns upward behind the obturator nerve and the external iliac artery and vein, to the medial border of the psoas major, behind which it divides into:* Lumbar branch of iliolumbar artery* Iliac branch of iliolumbar artery...
|
lumbar and iliac branches |
psoas major muscle The psoas major is a long fusiform muscle placed on the side of the lumbar region of the vertebral column and brim of the lesser pelvis. It joins the iliacus muscle to form the iliopsoas. In less than 50 percent of subjects the psoas major is accompanied by the psoas minor.-Origin:The psoas major...
, quadratus lumborum muscleThe Quadratus lumborum is irregular and quadrilateral in shape, and broader below than above.-Origin and insertion:It arises by aponeurotic fibers from the iliolumbar ligament and the adjacent portion of the iliac crest for about 5 cm., and is inserted into the lower border of the last rib for...
, iliacus muscleThe iliacus is a flat, triangular muscle, which fills the iliac fossa.- Course :The iliacus arises from the iliac fossa on the interior side of the hip bone, and also from the region of the anterior inferior iliac spine...
>-
| Posterior |
Lateral sacral arteries |
superior and inferior branches |
anterior sacral foramina At the ends of the transverse ridges of the pelvic surface of the sacrum are seen the anterior sacral foramina , four in number on either side, somewhat rounded in form, diminishing in size from above downward, and directed lateralward and forward.They give exit to the anterior divisions of the...
>-
| Posterior |
Superior gluteal artery The superior gluteal artery is the largest branch of the internal iliac artery, and appears to be the continuation of the posterior division of that vessel....
|
- |
greater sciatic foramen -Boundaries:It is bounded as follows:* anterolaterally by the greater sciatic notch of the illium* posteromedially by the sacrotuberous ligament* inferiorly by the sacrospinous ligament and the ischial spine* superiorly by the anterior sacroilliac ligament...
>-
| Anterior |
Obturator arteryThe obturator artery passes antero-inferiorly on the lateral wall of the pelvis, to the upper part of the obturator foramen, and, escaping from the pelvic cavity through the obturator canal, it divides into both an anterior and a posterior branch.-Inside the pelvis:In the pelvic cavity this vessel...
(occasionally from inferior epigastric arteryIn human anatomy, inferior epigastric artery refers to the artery that arises from the external iliac artery and anastomoses with the superior epigastric artery...
) |
- |
obturator canal The obturator canal is a passageway formed in the obturator foramen by part of the obturator membrane. It connects the pelvis to the thigh.The obturator artery, obturator vein, and obturator nerve all travel through the canal.-Pathology:...
>-
| Anterior |
Inferior gluteal artery The inferior gluteal artery , the larger 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....
|
- |
greater sciatic foramen -Boundaries:It is bounded as follows:* anterolaterally by the greater sciatic notch of the illium* posteromedially by the sacrotuberous ligament* inferiorly by the sacrospinous ligament and the ischial spine* superiorly by the anterior sacroilliac ligament...
>-
| Anterior |
Umbilical artery The umbilical artery is a paired artery that is found in the abdominal and pelvic regions. In the fetus, it extends into the umbilical cord.-Umbilical arteries in the fetus:...
|
superior vesical artery The superior vesical artery supplies numerous branches to the upper part of the bladder.From one of these a slender vessel, the artery to the ductus deferens, takes origin and accompanies the duct in its course to the testis, where it anastomoses with the internal spermatic artery.Other branches...
(usually, but sometimes it branches directly from anterior trunk) |
medial umbilical ligament The medial umbilical ligament 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.-Origins:...
>-
| Anterior |
Uterine artery -Structure:The uterine artery usually arises from the anterior division of the internal iliac artery. It travels to the uterus, crossing the ureter anteriorly, reaching the uterus by traveling in the transverse cervical ligament....
(females) or deferential artery (males) |
superior and vaginal branches |
uterusThe uterus is a major female hormone-responsive reproductive sex organ of most mammals, including humans. It is within the uterus that the fetus develops during gestation. The term uterus is used consistently within the medical and related professions; the Germanic term, womb is more common in...
, vas deferensThe vas deferens , also called ductus deferens, , is part of the male anatomy of some species; they transport sperm from the epididymis in anticipation of ejaculation.-Structure:...
>-
| Anterior |
Vaginal artery -Terminology:The vaginal artery is usually defined as a branch of the internal iliac artery.Some sources say that the vaginal artery can arise form the internal iliac artery or the uterine artery...
(females, can also arise from uterine artery-Structure:The uterine artery usually arises from the anterior division of the internal iliac artery. It travels to the uterus, crossing the ureter anteriorly, reaching the uterus by traveling in the transverse cervical ligament....
) |
- |
vaginaThe vagina is a fibromuscular tubular tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles. Female insects and other invertebrates also have a vagina, which is the terminal part of the...
>-
| Anterior |
inferior vesical artery The INF vesical artery is an artery in the pelvis that supplies the lower part of the bladder.-Structure:The inferior vesical artery is a branch of the anterior division of the internal iliac artery. It frequently arises in common with the middle rectal artery, and is distributed to the fundus of...
|
- |
urinary bladder In anatomy, the urinary bladder is the organ that collects urine excreted by the kidneys prior to disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...
>-
| Anterior |
Middle rectal arteryThe middle rectal artery is an artery in the pelvis that supplies blood to the rectum.-Structure:The middle rectal artery usually arises with the inferior vesical artery, a branch of the internal iliac artery...
|
- |
rectum The rectum is the final straight portion of the large intestine in some mammals, and the gut in others, terminating in the anus. The human rectum is about 12 cm long...
>-
| Anterior |
Internal pudendal arteryThe internal pudendal artery is an artery that branches off the internal iliac artery, providing blood to the external genitalia.The internal pudendal artery is the terminal branch of the anterior trunk of the internal iliac artery...
|
many branches - see article for details |
greater sciatic foramen -Boundaries:It is bounded as follows:* anterolaterally by the greater sciatic notch of the illium* posteromedially by the sacrotuberous ligament* inferiorly by the sacrospinous ligament and the ischial spine* superiorly by the anterior sacroilliac ligament...
|
Structure in fetus
In the
fetusA fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth. The plural is fetuses....
, 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
bladderIn anatomy, the urinary bladder is the organ that collects urine excreted by the kidneys prior to disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...
, and runs upward on the back of the anterior wall of the abdomen to the
umbilicusUmbilicus may refer to:*Umbilicus , a feature of gastropod, Nautilus and Ammonite shell anatomy*umbilicus, a synonym for the navel or belly button....
, converging toward its fellow of the opposite side.
Having passed through the umbilical opening, the two arteries, now termed umbilical, enter the
umbilical cordIn placental mammals, the umbilical cord is the connecting cord from the developing embryo or fetus to the placenta...
, where they are coiled around the umbilical vein, and ultimately ramify in the
placentaThe placenta is an organ unique to mammals that connects the developing fetus to the uterine wall. The placenta supplies the fetus with oxygen and food, and allows fetal waste to be disposed of via the maternal kidneys...
.
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 ligamentThe medial umbilical ligament 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.-Origins:...
(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
sacrumThe sacrum is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx...
and the upper border of the
greater sciatic foramen-Boundaries:It is bounded as follows:* anterolaterally by the greater sciatic notch of the illium* posteromedially by the sacrotuberous ligament* inferiorly by the sacrospinous ligament and the ischial spine* superiorly by the anterior sacroilliac ligament...
.
The right and left hypogastric arteries in a series of cases often differed in length, but neither seemed constantly to exceed the other.
Collateral Circulation
The circulation after ligature of the internal iliac artery is carried on by the anastomoses of:
- 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 with the inferior vesical artery, a branch of the internal iliac artery...
and the superior rectal arteryThe superior rectal 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...
- the iliolumbar artery
-Course:The iliolumbar artery turns upward behind the obturator nerve and the external iliac artery and vein, to the medial border of the psoas major, behind which it divides into:* Lumbar branch of iliolumbar artery* Iliac branch of iliolumbar artery...
with the last lumbar artery
- the lateral sacral arteries with the median sacral artery
The median sacral artery is a small vessel, which arises from the back of the aorta, a little above its bifurcation....
External links