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Anatomy of the Spinal Cord

The spinal cord is part of the central nervous system. It relays sensations to the brain, and allows the brain to control movements and function of the internal organs, trunk, and arms and legs. The spinal cord is made up of bundles of nerves The spinal cord carries signals from your body to your brain, and vice versa.

The spinal cord is tube-shaped and extends from the brain all the way down to the top of the lumbar spine, or the lower region of the spine. Branching off from the spinal cord are small nerves called nerve roots. These roots come out from small spaces between the bones (vertebrae) that surround the spinal cord and run to different parts of the body.

The entire spinal cord is surrounded by a liquid called cerebrospinal fluid, or CSF. CSF protects the spinal cord from injury. The spinal cord is also protected by 3 layers of coverings called the meninges. They are the dura mater, the arachnoid mater, and the pia mater.

The spinal cord and spine are divided into 4 regions from top to bottom: cervical, thoracic, lumbar, and sacral. Damage to the nerves in the spinal cord can result in many health conditions, depending on the region that is affected.

Anatomy of the spinal cord
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Cervical region

This portion of the spinal cord contains nerve roots that connect to the upper body, arms, and hands. Nerves going to and coming from the lower parts of the body have to pass through the cervical spinal cord. These nerves are bundled into tracts. Between the vertebrae in the spine are spongy cushions called intervertebral disks. If the disks collapse, they may squeeze (pinch) the nerves in the cervical spine. This can lead to a condition called cervical radiculopathy. This condition can cause pain, weakness, or numbness in the arms. If the cervical region is severely injured, such as when the tracts are injured, most of the body can be paralyzed (quadriplegia). This can also lead to loss of control of some organs such as bowel and bladder control. Severe injuries can occur from a fall or from certain health conditions. These conditions include a herniated disk. This is when the spongy cushion slips out, pressing against nearby nerves. Another condition is spinal stenosis, where the spinal canal narrows and pinches the nerves.

Thoracic region


Lumbar region


Sacral region


Keeping your spinal cord healthy

Some spinal cord injuries can’t always be avoided, such as those caused by car accidents. But you can take many steps to preserve the health of your spine and the spinal cord nerves within it. Car crash injuries may be reduced by correctly using seat belts and air bags. Staying at or reaching a healthy weight is suggested because excess pounds can put unneeded stress on your back. It's also important to maintain good posture, stretch and take part in physical activities that strengthen your back muscles. To strengthen the bones of your spine and protect your spinal cord, a vitamin D-rich diet is also essential. Finally, know your limits and avoid picking up items that are too heavy for you to lift safely. Use correct lifting techniques.

Online Medical Reviewer: Joseph Campellone MD
Online Medical Reviewer: Raymond Kent Turley BSN MSN RN
Online Medical Reviewer: Trina Bellendir PT
Date Last Reviewed: 3/1/2020