artery
An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pu ...
that supplies the anterior portion of the
spinal cord
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the sp ...
. It arises from branches of the
vertebral arteries
The vertebral arteries are major arteries of the neck. Typically, the vertebral arteries originate from the subclavian arteries. Each vessel courses superiorly along each side of the neck, merging within the skull to form the single, midline ...
and courses along the anterior aspect of the spinal cord. It is reinforced by several contributory arteries, especially the artery of Adamkiewicz.
Path
The anterior spinal artery arises bilaterally as two small branches near the termination of the
vertebral arteries
The vertebral arteries are major arteries of the neck. Typically, the vertebral arteries originate from the subclavian arteries. Each vessel courses superiorly along each side of the neck, merging within the skull to form the single, midline ...
. One of these vessels is usually larger than the other, but occasionally they are about equal in size. Descending in front of the medulla oblongata, they unite at the level of the foramen magnum. The single trunk descends in the front of the
medulla spinalis
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spinal ...
, extending to the lowest part of the medulla spinalis. It is continued as a slender twig on the
filum terminale
The filum terminale ("terminal thread") is a delicate strand of fibrous tissue, about 20 cm in length, proceeding downward from the apex of the conus medullaris. It is one of the modifications of pia mater. It gives longitudinal support to th ...
vertebral canal
The spinal canal (or vertebral canal or spinal cavity) is the canal that contains the spinal cord within the vertebral column. The spinal canal is formed by the vertebrae through which the spinal cord passes. It is a process of the dorsal body c ...
through the
intervertebral foramina
The intervertebral foramen (also called neural foramen, and often abbreviated as IV foramen or IVF) is a foramen between two spinal vertebrae. Cervical, thoracic, and lumbar vertebrae all have intervertebral foramina.
The foramina, or openin ...
. These branches are derived from the
vertebral artery
The vertebral arteries are major arteries of the neck. Typically, the vertebral arteries originate from the subclavian arteries. Each vessel courses superiorly along each side of the neck, merging within the skull to form the single, midline ba ...
inferior thyroid artery
The inferior thyroid artery is an artery in the neck. It arises from the thyrocervical trunk and passes upward, in front of the vertebral artery and longus colli muscle. It then turns medially behind the carotid sheath and its contents, and als ...
thorax
The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the cre ...
iliolumbar artery
The iliolumbar artery is the first branch of the posterior trunk of the internal iliac artery.
Structure
The iliolumbar artery is the first branch of the posterior trunk of the internal iliac artery. It turns upward behind the obturator nerve a ...
and
lateral sacral arteries
The lateral sacral arteries is an artery in the pelvis that arises from the posterior division of the internal iliac artery. It later splits into two smaller branches, a superior and an inferior.
Structure
The lateral sacral artery is the se ...
in the
abdomen
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the to ...
pia mater
Pia mater ( or ),Entry "pia mater" in anterior median fissure. It supplies that membrane, and the substance of the medulla spinalis, also sending off branches at its lower part to be distributed to the
cauda equina
The cauda equina () is a bundle of spinal nerves and spinal nerve rootlets, consisting of the second through fifth lumbar nerve pairs, the first through fifth sacral nerve pairs, and the coccygeal nerve, all of which arise from the lumbar enlarg ...
.
Disorders
Disruption of the anterior spinal artery leads to bilateral disruption of the
corticospinal tract
The corticospinal tract is a white matter motor pathway starting at the cerebral cortex that terminates on lower motor neurons and interneurons in the spinal cord, controlling movements of the limbs and trunk. There are more than one million neur ...
, causing motor deficits, and bilateral disruption of the
spinothalamic tract
The spinothalamic tract is a part of the anterolateral system or the ventrolateral system, a sensory pathway to the thalamus. From the ventral posterolateral nucleus in the thalamus, sensory information is relayed upward to the somatosensory co ...
, causing sensory deficits in the form of pain/temperature sense loss. It is called
anterior spinal artery syndrome
Anterior spinal artery syndrome (also known as "anterior spinal cord syndrome") is syndrome caused by ischemia of the anterior spinal artery, resulting in loss of function of the anterior two-thirds of the spinal cord. The region affected inclu ...
. This occurs when the disruption of the anterior spinal artery is at the level of the spinal cord. Contrast this with
medial medullary syndrome
Medial medullary syndrome, also known as inferior alternating syndrome, hypoglossal alternating hemiplegia, lower alternating hemiplegia, or Dejerine syndrome, is a type of alternating hemiplegia characterized by a set of clinical features result ...
, when the anterior spinal artery is occluded at the level of the medulla oblongata.
Disruption of its perforating branches (sulcal artery) can result in a hemicord syndrome. In fact, acute sulcal artery syndrome should be suspected in patients with acute hemicord syndrome, and vertebral artery dissection should be suspected in cases of high cervical cord involvement. In a recent review by Tan YJ, et al. in 2021, good functional recovery was seen in most, and vertebral artery dissection was the leading cause of sulcal artery syndrome.
Additional images
Image:Arteries_beneath_brain.png, The arteries of the base of the brain.
Image:Circle of Willis en.svg , Arteries of the
brain
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...
,
brain stem
The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is co ...
and upper
spinal cord
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the sp ...