Iliolumbar artery
Arteria iliolumbalis
A paired branch of the internal iliac artery that climbs out of the pelvis behind psoas major to supply the iliac fossa and lower lumbar region.
At a glance
- English
- Iliolumbar artery
- Latin (TA2)
- Arteria iliolumbalis
- System
- Artery
- Region
- Trunk
- Side
- Paired, left and right
About the iliolumbar artery
Of the vessels leaving the internal iliac artery's posterior trunk, the iliolumbar artery normally comes off first. It is a short vessel that reverses direction soon after it starts: instead of running down into the pelvis, it turns upwards and laterally towards the posterior abdominal wall.
On its way it passes behind the obturator nerve and behind the external iliac vessels, then crosses in front of the sacroiliac joint and the lumbosacral trunk to reach the medial border of psoas major. Behind that muscle it splits into its two terminal branches. The lumbar branch climbs to supply psoas major, quadratus lumborum and the lowest part of the vertebral canal, much like a fifth lumbar artery. The iliacus branch runs laterally into the iliac fossa to feed iliacus and the ilium and to reach the iliac crest.
The vessel takes part in a rich set of links around the pelvis. Its lumbar branch meets the last lumbar artery, and its iliac twigs join the deep circumflex iliac, superior gluteal, obturator and lateral circumflex femoral arteries. Further connections between sacral, rectal, gluteal and circumflex femoral branches make the whole pelvic wall a network fed from several directions.
Because of these anastomoses, blood can still reach the pelvic wall and hip region when the internal iliac artery or one of its trunks is blocked or deliberately closed, as may be done to control pelvic bleeding. Surgeons working near the sacroiliac joint or the lumbosacral junction, and those placing screws in the posterior pelvis, keep the course of the artery in mind.
Course and supply
- Arises from
- Normally the earliest branch to leave the internal iliac artery's posterior trunk.
- Ends in
- Divides behind psoas major into a lumbar branch and an iliacus branch.
- Supplies
- Supplies psoas major, quadratus lumborum, iliacus, the ilium and the lower vertebral canal, with twigs to the gluteal and abdominal wall muscles along the iliac crest.
Anthromica
See the iliolumbar artery where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
