Spinal branch of iliolumbar artery
Ramus spinalis arteriae iliolumbalis
A small branch of the iliolumbar artery that enters the vertebral canal at the lumbosacral junction to supply the cauda equina and its coverings.
At a glance
- English
- Spinal branch of iliolumbar artery
- Latin (TA2)
- Ramus spinalis arteriae iliolumbalis
- System
- Artery
- Region
- Trunk
- Side
- Paired, left and right
About the spinal branch of iliolumbar artery
The iliolumbar artery is the first branch of the posterior division of the internal iliac artery. It climbs out of the pelvis in front of the sacroiliac joint and the lumbosacral trunk, behind the obturator nerve and the external iliac vessels, and reaches the medial border of psoas major. There it divides into a lumbar branch and an iliac branch. The lumbar branch takes the place, in effect, of a fifth lumbar artery, and its spinal branch is the vessel described here.
The spinal branch leaves the lumbar branch and passes medially through the intervertebral foramen between the fifth lumbar vertebra and the sacrum. Inside the vertebral canal it follows the general plan of the spinal branches of segmental arteries: it gives twigs to the vertebral bodies and the posterior arch, to the dura and the epidural tissue, and radicular branches that follow the nerve roots.
At this level the spinal cord has already ended, so the vessel supplies the roots of the cauda equina rather than the cord itself. It anastomoses with the spinal branches of the lumbar arteries above and of the lateral sacral arteries below, forming part of the chain of vessels around the lower vertebral canal.
Because it runs through the L5–S1 foramen alongside the fifth lumbar nerve, the branch lies in the field of spinal procedures at this common site of disc and foraminal disease.
Course and supply
- Arises from
- The lumbar branch of the iliolumbar artery, itself a branch of the posterior division of the internal iliac artery.
- Ends in
- Enters the vertebral canal through the intervertebral foramen between the fifth lumbar vertebra and the sacrum, ending in branches to bone, meninges and nerve roots.
- Supplies
- Supplies the lumbosacral vertebrae, the meninges and the roots of the cauda equina at the lumbosacral junction.
Anthromica
See the spinal branch of 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.
