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 brain.

Course

The vertebral arteries arise from the subclavian arteries, one on each side of the body, then enter deep to the transverse process at the level of the 6th cervical vertebrae (C6), or occasionally (in 7.5% of cases) at the level of C7. They then proceed superiorly, in the transverse foramen (foramen transversarium) of each cervical vertebra. Once they have passed through the transverse foramen of C1 (also known as the atlas), the vertebral arteries travel across the posterior arch of C1 and through the suboccipital triangle before entering the foramen magnum.

Nunziante Ippolito, a Neapolitan physician, identified the "angle of Nunziante Ippolito" to find the vertebral artery, between the anterior scalene muscle and the longus colli muscle.