Posterior spinal artery
Encyclopedia
The posterior spinal artery (dorsal spinal artery) arises from the vertebral artery
, adjacent to the medulla oblongata
.
, forming a plexus called the vasocorona. The posterior spinal arteries continue as the two major trunks down to the lower part of the medulla spinalis, and 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.
Vertebral artery
The vertebral arteries are major arteries of the neck. They branch from the subclavian arteries and merge to form the single midline basilar artery in a complex called the vertebrobasilar system, which supplies blood to the posterior part of the circle of Willis and thus significant portions of the...
, adjacent to the medulla oblongata
Medulla oblongata
The medulla oblongata is the lower half of the brainstem. In discussions of neurology and similar contexts where no ambiguity will result, it is often referred to as simply the medulla...
.
Path
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 radicular branches, which enter the vertebral canal through the intervertebral foraminaIntervertebral foramina
When the spinal vertebrae are articulated with each other the bodies form a strong pillar for the support of the head and trunk, and the vertebral foramina constitute a canal for the protection of the medulla spinalis...
, forming a plexus called the vasocorona. The posterior spinal arteries continue as the two major trunks down to the lower part of the medulla spinalis, and to the cauda equina
Cauda equina
The cauda equina is a structure within the lower end of the spinal column of most vertebrates, that consists of nerve roots and rootlets from above...
.
Branches from the posterior spinal arteries form a free anastomosis
Anastomosis
An anastomosis is the reconnection of two streams that previously branched out, such as blood vessels or leaf veins. The term is used in medicine, biology, mycology and geology....
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
Fourth ventricle
The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ventricle...
.
The posterior spinal artery can often originate from the posterior inferior cerebellar artery, rather than the vertebral.
