Posterior Spinal Arteries, Gross Anatomy

Description

Arising bilaterally from the vertebral arteries near the cervicomedullary junction, the posterior spinal arteries descend along the posterolateral sulci of the spinal cord, hugging the dorsal root entry zone and tracking inferiorly toward the thoracic levels. In the upper cervical region they sit posterior to the medulla and upper cervical cord, with a paired, near mirror-image course on either side of the posterior median sulcus. Small radiculopial contributions from segmental arteries would be expected to join them intermittently, reinforcing the longitudinal channels that anastomose via the pial arterial network. Symmetry dominates. Attention to the posterior spinal arteries matters because they define the dominant arterial supply to the dorsal one third of the cord, including the dorsal columns and portions of the dorsal horns, territories that produce a recognizable pattern of sensory loss when compromised. Vertebral artery dissection, occipito-cervical trauma, or iatrogenic injury during posterior fossa or upper cervical procedures can reduce flow in these vessels or their feeders, and the resulting posterior cord ischemia can be subtle compared with anterior spinal artery syndrome. Their relationship to the dorsal root entry zone also frames why radiculomedullary and radiculopial branches become clinically relevant during cervical and thoracic instrumentation and during endovascular planning. Use this artwork to support neuroanatomy and gross anatomy teaching on spinal cord vascular territories, paired longitudinal arteries, and cervicomedullary arterial connections. It also fits neurosurgery, neuroradiology, and stroke education materials that contrast posterior spinal artery infarction with anterior spinal artery infarction, or that introduce vertebral artery pathology at the level of the brainstem and upper cervical cord. Anatomical accuracy verified by SciePro's Medical Advisory Board.