Anatomy

Anatomy of Neck Pain

The Parts of the Cervical Spine and How They Work

In general, the neck includes the cervical spine (the upper most part of the spine) and the soft tissues that surround the cervical spine. These soft tissues include: nerves, muscles, ligaments, tendons, and blood vessels. The cervical spine is made up of the first seven vertebrae in the spine. Your doctor will usually refer to these bones as C1 through C7. The cervical spine starts just below the skull and ends just above the thoracic spine. The spine has two main functions:

To protect and support the spinal cord
To give structure and support to our body allowing us to stand up straight"

The vertebrae are the 24 bones that are linked together to make up the spinal column. Just as the bones of the skull protect our brain, the bones of the spine protect the spinal cord. The spinal cord is the large collection of nerves that connects the brain to the rest of the body.

In the center of each vertebra is a large hole. Because the vertebrae are all linked together, these holes line up to form a "bony tube", called the spinal canal, through which the spinal cord passes. This bony tube makes up the spinal canal, which provides protection and support for the spinal cord.

As the spinal cord leaves the brain, it travels down the spinal canal to the tailbone. Along the way, it gives off smaller nerves that leave the spine between each vertebra through an opening called the foramen. The nerves that leave the spine in the upper area, or the cervical spine, travel into the arms to the hands. The nerves that leave the spine in the chest area, or thoracic spine, mostly go into the chest and belly area. The nerves that leave the spinal canal in the lower spine, or the lumbar spine, travel into the legs and feet.

To better understand how the parts of the spine work together, let's look at a spinal segment. A spinal segment is made up of: two vertebrae, the intervertebral disc between the vertebrae, and the two nerve roots, one from each side that "branch off of " the spine. The cervical vertebrae are the smallest vertebrae in the spine because they do not have the weight-bearing function of the vertebrae in the back. One pair of spinal nerves exits through the gap between the vertebrae in each segment. One common cause of pain comes from pressure on the nerve roots, sometimes causing pain and numbness in the neck or in the lower body.

The space between two vertebrae contains a large round disc of connective tissue, called an intervertebral disc. By looking at the intervertebral disc from above, we can see an outer ring, called the annulus, and a soft spongy center, called the nucleus pulposus. The annulus is the strongest part of the disc and helps keep the spongy center inside the disc. The nucleus pulposus acts as a shock absorber to cushion the bones from pressure during twisting, jumping, and weight bearing.

A joint is formed where two or more bones meet. Bony knobs, called facets, extend from each vertebra and overlap each other to form a facet joint. Facet joints link the vertebrae together like a chain, and provide a mobile connection between each vertebra. The facet joints are important because they allow the neck to bend and turn. Each vertebra can move only a little, but the chain of small movements combined makes the spine very flexible.