Posterior spinal artery

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Posterior spinal artery
CerebellumArteries.jpg
The three major arteries of the cerebellum: the SCA, AICA, and PICA. (Posterior spinal artery is not labeled, but region is visible.)
Gray770-vessels.png
Details
Source Vertebral or
posterior inferior cerebellar
Branches Descending and ascending branch
Vein Posterior spinal veins
Identifiers
Latin Arteria spinalis posterior
Dorlands
/Elsevier
a_61/12156012
TA A12.2.08.013
FMA 50531
Anatomical terminology

The posterior spinal artery (dorsal spinal arteries) arises from the vertebral artery, adjacent to the medulla oblongata. It supplies the grey and white posterior columns of the spinal cord.

Structure[edit]

It passes posteriorly to descend the medulla passing in front of the posterior roots of the spinal nerves. Along its course it is reinforced by a succession of segmental or radiculopial branches, which enter the vertebral canal through the intervertebral foramina, forming a plexus called the vasocorona with the anterior verterbral arteries. Below the medulla spinalis and upper cervical spine, the posterior spinal arteries are rather discontinuous; unlike the anterior spinal artery, which can be traced as a distinct channel throughout its course, the posterior spinal arteries are seen as somewhat larger longitudinal channels of an extensive pial arterial meshwork. At the level of the conus medullaris, the posterior spinals are more frequently seen as distinct arteries, communicating with the anterior spinal artery to form a characteristic "basket"[1] which angiographically defines the caudal extent of the spinal cord and its transition to the cauda equina.

Branches from the posterior spinal arteries form a free anastomosis around the posterior roots of the spinal nerves, and communicate, by means of very tortuous transverse branches, with the vessels of the opposite side.

Close to its origin each posterior spinal artery gives off an ascending branch, which ends ipsilaterally near the fourth ventricle.

The posterior spinal artery can often originate from the posterior inferior cerebellar artery, rather than the vertebral.

Functions[edit]

Most cranially, the posterior spinal artery supplies the dorsal column of the closed medulla containing fasiculus gracilis, gracile nucleus, fasciculus cuneatus, and cuneate nucleus. At the spinal cord level, the posterior spinal artery supplies the dorsal and lateral column as well as the peripheral part of the anterior and central column.[2]

Clinical significance[edit]

Disruption of blood supply to this particular artery in the medulla would result in a number of sensory deficits. If occlusion occurs above the level of sensory decussation, it would affect the propioception, vibration, and two-point discrimination of the contralateral side of the body. When occurs above the level of sensory decussation, however, it would cause the effect on the ipsilateral side instead. Particularly at the upper cervical spinal cord where the posterior spinal artery supplies some parts of the ventral column, lesion might extend to the anterolateral system and triggers the loss of pain and temperature sensation on the contralateral side of the body.

References[edit]

  1. ^ "Spinal Arterial Anatomy | neuroangio.org". neuroangio.org. Retrieved 2017-03-13. 
  2. ^ Lamin, S.; Bhattacharya, J. J. (2003-04-01). "Vascular Anatomy of the Spinal Cord and Cord Ischaemia". Practical Neurology. 3 (2): 92–95. doi:10.1046/j.1474-7766.2003.07133.x. ISSN 1474-7758. 

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)

External links[edit]