Posterior spinal arteries

Last revised by Dr Bahman Rasuli on 20 Sep 2022


The posterior spinal arteries are a pair of arteries that supply the respective ipsilateral grey and white posterior columns of the spinal cord.

Gross anatomy

The posterior spinal arteries arise from either the posterior inferior cerebellar or vertebral arteries (V3 or V4 segments) and run the entire posterolateral aspect of the spinal cord. Its origin may be intra-dural or extra-dural 1,2.

It descends along the posterolateral surface of the spinal cord. Along its course, it is reinforced by other branches that enter the spinal canal via the intervertebral foraminae. Although communication exists at multiple levels, the supply of the cord can be thought of as occurring in three relatively separate sections like the anterior spinal artery, supplied by somewhat predictable feeders:   

The posterior spinal artery often anastomoses with the contralateral posterior spinal artery and may receive anastomoses with the anterior spinal artery via a pial plexus that encases the cord.

See spinal cord blood supply.

Related pathology


ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Figure 1: spinal cord arterial supply
    Drag here to reorder.
  • Figure 2: cord supply of the PSA
    Drag here to reorder.
  • Figure 3: brainstem arterial territories
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.