Posterior spinal artery

Overview
The posterior spinal artery (dorsal spinal artery) arises from the vertebral artery, adjacent to the medulla oblongata. 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 foramina, 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.