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1. Blood supply of the spinal cord
A. Arterial supply:
1. Anterior spinal artery: It is a single artery that arises from both vertebral arteries. It
descends in front of the anteromedian fissure. The anterior spinal arteries supply the
anterior two thirds of the spinal cord.
2. Posterior spinal arteries: Two arteries, each one arises from the corresponding
vertebral artery. Each artery divides into two longitudinal branches which descend on
each side of the posterior root of the spinal nerves. The posterior spinal arteries supply
the posterior third of the spinal cord.
3. Radicular arteries:Run along the roots of the spinal nerve to reach the spinal cord.
These arteriesarise from the second part of vertebral, ascending cervical, deep cervical,
superior intercostals, posterior intercostals, subcostal and upper lumbar arteries.
The radicular arteries anastomose together and with the anterior and posterior spinal
arteries around the circumference of the cord. In addition, they form longitudina l
anastomotic arterial channels on the surface of the cord.
B. Venous drainage:
There are six longitudinal veins which run along the spinal cord. These are:
1. Anterior spinal vein: In front of the anteromedian sulcus.
2. Posterior spinal vein: Behind the posteromedian septum.
3. Anterolateral spinal veins (two):One on each side, lying in front the attachment of
the ventral root of the spinal nerve.
4. Posterolateral spinal veins (two): One on each side, lying behind of the attachment
of the dorsal root of the spinal nerve.
These six longitudinal veins anastomose freely with each other around the spinal cord.
They communicate above with the cranial venous sinuses and with the cerebellar veins. In the
vertebral canal, these spinal veins communicate with the internal vertebral venous plexus and

2. with the segmental veins outside the vertebral canal through radicular veins which run along
the spinal nerves.
Fig : Blood supply of the spinal cord .