A person with disk disease in the neck may have a herniated disk or disk degeneration.

A person with a herniated disk has weakness in the outer wall of the disk. This allows the soft tissue that makes up the inside of the disk to push against the weakened outer layer. As a result, a bulge forms in the side of the disk: the bulge becomes more prominent when the disk is under stress during lifting, or twisting of the spine. In turn, this bulge can place pressure on the nerves in the spinal canal.

A person with disk degeneration has a disk that has broken down. This reduces the space between the two vertebrae that attach to the top and the bottom of the disk. In turn, this reduces the space for the nerves that branch off the spinal cord and pass between the vertebrae.