[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Spine](https://durgical.com/en/anatomy/region/spine/) › Anterior spinal artery [Cardiovascular system](https://durgical.com/en/anatomy/system/cardiovascular-system/) · [Spine](https://durgical.com/en/anatomy/region/spine/) # Anterior spinal artery The anterior spinal artery is a single small artery down the front of the [spinal cord](https://durgical.com/en/anatomy/spinal-cord/); it feeds the front two-thirds, including movement pathways. [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=spine&select=anterior_spinal_artery&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A single small artery running down the front of the spinal cord. ## What it does Supplies the front two-thirds of the cord, including the movement pathways. ## Key points - Anterior spinal artery syndrome: sudden weakness (paraplegia or quadriplegia), loss of pain and temperature below the level and bladder dysfunction, with vibration and joint position sense preserved - A single midline channel in the anterior median fissure; each of its sulcal branches turns into one half of the cord - Feeders are sparse in the mid-thoracic cord (about T4–T9), a watershed zone that is the most vulnerable to low blood pressure ## Key facts **Origin** Union of a branch from each vertebral artery near the foramen magnum **Branches** Sulcal (central) arteries into the cord; reinforced along its length by segmental medullary arteries from the vertebral, ascending and deep cervical, posterior intercostal, lumbar and lateral sacral arteries (e.g. Adamkiewicz) **Supplies** Anterior two-thirds of the cord: anterior horns, corticospinal and spinothalamic tracts; occlusion spares the dorsal columns ## Relations **Course** Formed near the [foramen magnum](https://durgical.com/en/anatomy/foramen-magnum/) by a branch from each [vertebral artery](https://durgical.com/en/anatomy/vertebral-artery/), which alone feeds only the upper cervical cord; below, it runs down the anterior median fissure as a chain kept up by a few anterior segmental medullary arteries, and joins the [posterior spinal arteries](https://durgical.com/en/anatomy/posterior-spinal-arteries/) in a loop around the [conus medullaris](https://durgical.com/en/anatomy/conus-medullaris/) **Deep** Sulcal (central) arteries enter the fissure to reach the anterior horns and the anterior and lateral columns **Lateral** Anterior nerve rootlets on each side, along which the segmental medullary arteries arrive to join it **Superficial** Pia mater, which carries it, then the subarachnoid space, the arachnoid and the dura ## Examination - Comparison of pinprick and temperature with vibration (tuning fork) and joint position: loss of the first two with the last two kept points to the anterior cord ## On imaging MRI with diffusion-weighted sequences shows the infarct; on axial T2 images the bright, paired anterior horns give the "owl's eyes" (or "snake eyes") sign. ## Clinical notes - Classic causes: surgery or stent-grafting of the thoracoabdominal aorta, aortic dissection, severe hypotension and, in the neck, compression by a large disc or osteophyte - Particulate injections around a nerve root (transforaminal epidural injection) can, rarely, enter a radicular feeder and infarct the cord - Weakness is often flaccid at first, with spasticity and brisk reflexes developing below the level over the following weeks ## Development It forms when paired longitudinal channels on the front of the cord fuse in the midline; short doubled segments can remain. ## Related conditions - [Spinal cord injury](https://durgical.com/en/conditions/spinal-cord-injury/) ## Test yourself Think of the answer, then tap the question to see it. ## How is the anterior spinal artery formed? By the union of a branch from each vertebral artery near the foramen magnum; it then runs down the anterior median fissure. ## What deficits define anterior spinal artery syndrome? Sudden paraplegia or quadriplegia, loss of pain and temperature below the level and bladder dysfunction, with vibration and joint position sense preserved. ## Why are vibration and position sense spared when the anterior spinal artery is occluded? The anterior spinal artery supplies only the anterior two-thirds of the cord; the dorsal columns belong to the posterior spinal arteries. ## Which segment of the cord supplied by the anterior spinal artery is most vulnerable to low blood pressure? The mid-thoracic cord, about T4–T9: feeders are sparse there, making it a watershed zone. ## What MRI sign suggests an anterior spinal artery infarct? The «owl's eyes» (or «snake eyes») sign: bright paired anterior horns on axial T2, with restricted diffusion. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/anatomy/anterior-spinal-artery/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** arteria spinalis anterior TA2 4525 **Official Spanish (DeCS)** Arteria espinal anterior **English (TA2)** Anterior spinal artery **Also called** arteria spinalis ventralis ## Related - [Artery of Adamkiewicz](https://durgical.com/en/anatomy/great-radicular-artery/) - [Posterior spinal arteries](https://durgical.com/en/anatomy/posterior-spinal-arteries/) - [Vertebral artery](https://durgical.com/en/anatomy/vertebral-artery/) - [Spinal cord](https://durgical.com/en/anatomy/spinal-cord/) - [Conus medullaris](https://durgical.com/en/anatomy/conus-medullaris/) Sources: Terminologia Anatomica (TA2); [Neuroanatomy, Spinal Cord](https://www.ncbi.nlm.nih.gov/books/NBK559056/); Tratado de anatomía humana (9.ª ed.), tomo II, Libro V Sistema nervioso central, sección 1: Médula espinal. ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/anterior-spinal-artery/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/anterior-spinal-artery/