The blood supply to the spinal cord arises from three arteries which run the whole length of the spinal cord .
The Anterior spinal artery:
This artery arises from each vertebral artery at the level of the foramen magnum.
The Posterior spinal arteries:
These 2 arteries arise from the posterior inferior cerebellar artery at the same level.
The central area supplied only by the anterior spinal artery is predominantly a motor area.
At each spinal level, radicular arteries arise from local vessels (e.g. intercostal, lumbar arteries) and feed the spinal arteries. The most important of these is the artery of Adamkiewicz which arises from lower thoracic/upper lumbar segmental arteries.
Generally the proportion of flow is greatest from the radicularis magna ‘feeder’ artery (artery of Adamkiewicz) to the thoracolumbar region.
In abnormal situations (e.g. high take-off) the iliac artery branch may supply the lower thoracolumbar region of the cord entering by way of the intervertebral foramen in the vicinity of L4-5.