Corpus: Anterior spinal artery

The anterior spinal artery is an unpaired artery that arises from the two vertebral arteries. It is the primary artery responsible for supplying the spinal cord.

The anterior spinal artery runs within the spinal canal along the ventral side of the spinal cord. It forms at the level of the pyramidal decussation (where the pyramidal tracts cross) from the convergence of the two vertebral arteries. The artery then descends along the anterior median fissure of the spinal cord. Throughout its course, it receives numerous contributions from the anterior radicular arteries, which themselves arise from the spinal branches of segmental arteries, such as the intercostal arteries.

The anterior spinal artery forms anastomoses with the two posterior spinal arteries on the dorsal side of the spinal cord through transverse and longitudinal collateral vessels of the pia mater.

Occlusion of the anterior spinal artery, due to thrombosis or embolism, can result in anterior spinal artery syndrome, a condition characterized by the loss of motor function and pain/temperature sensation, with preserved proprioception and vibration sense.