The vertebral arteries run through the spinal column in the neck to provide blood to the brain and spine. The vertebral arteries are part of the circulatory system. They carry blood to the brain and spinal cord, which are part of the nervous system.
The vertebral arteries in the neck supply blood to the brain and spine. The name vertebral refers to the arteries’ location along the vertebrae, the bones of the spine.
You have a left vertebral artery and a right vertebral artery that run through the spinal column. The two vertebral arteries join together at the base of the skull to form the basilar artery and together are called the vertebrobasilar system.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
The vertebral arteries are part of the circulatory system. They carry blood to the brain and spinal cord, which are part of the nervous system. The vertebral artery provides 20% of blood flow to your brain (the carotid artery supplies the other 80%).
The vertebral arteries have many small branches. The largest branch — the posterior inferior cerebellar artery — is one of three main arteries that provide the cerebellum with blood. Part of the brain, the cerebellum plays a key role in balance, movement, speech and vision.
The two vertebral arteries start at the subclavian arteries. The subclavian arteries sit below the collarbone (clavicle). They arise from the aorta, the body’s largest blood vessel, which carries blood from the heart. Specifically, the right subclavian arises from the brachiocephalic artery, which arises from the aorta. The left subclavian arises directly from the aorta.
The vertebral arteries run separately inside the left and right sides of the spinal column in the neck. The suboccipital muscles at the base of the skull cover the vertebral arteries. This area is the suboccipital triangle.
The vertebral arteries divide into four segments based on where they are within the spinal column:
Fat and cholesterol deposits (plaque) can build up in the vertebral arteries. This buildup can narrow the arteries, causing atherosclerosis. If there’s too much plaque, blockages may occur.
When atherosclerosis develops in the vertebral arteries, you have vertebral artery stenosis. This can lead to:
Other conditions can also effect the vertebral arteries:
These lifestyle changes can lower the risk of vertebral artery stenosis:
You should call your healthcare provider if you experience:
A note from Cleveland Clinic
The vertebral arteries provide blood to the brain and spine, keeping the nervous system healthy. Vertebral artery stenosis, or vertebrobasilar insufficiency, is the result of plaque collecting in the arteries. The plaque makes the arteries narrow, slowing blood flow. This increases your risk for strokes, including TIAs. If you’re at risk for vertebral artery stenosis, you can make lifestyle changes to lower your stroke risk.
Last reviewed by a Cleveland Clinic medical professional on 07/23/2021.
Learn more about our editorial process.