Each segmental medullary artery is a branch of the cervical part of the vertebral artery

Vertebral artery

The vertebral arteries are major arteries of the neck. They branch from the subclavian arteries and merge to form the single midline basilar artery in a complex called the vertebrobasilar system, which supplies blood to the posterior part of the circle of Willis and thus significant portions of the...

. These small branches penetrate into the vertebral bone through small openings such as the intervertebral foramina

Intervertebral foramina

When the spinal vertebrae are articulated with each other the bodies form a strong pillar for the support of the head and trunk, and the vertebral foramina constitute a canal for the protection of the medulla spinalis...

. These segmental arteries provide blood flow to the surface and inside the spinal canal at each segmental level.

The largest anterior segmental medullary artery is also known as the artery of Adamkiewicz

Artery of Adamkiewicz

In human anatomy, the Artery of Adamkiewicz is the largest anterior segmental medullary artery.It has several other names, including:* Adamkiewicz artery* great radicular artery of Adamkiewicz* major anterior segmental medullary artery...

.

They can join the anterior spinal artery

Anterior spinal artery

In human anatomy, the anterior spinal artery is the blood vessel that supplies the anterior portion of the spinal cord. It arises from branches of the vertebral arteries and is supplied by the anterior segmental medullary arteries, including the artery of Adamkiewicz, and courses along the anterior...

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