The bones (vertebrae) that form the spine (backbone) are cushioned by small, round, flat discs. When these discs are damaged from an injury, normal wear and tear, or disease, they may bulge or break open. This is called a herniated or slipped disc.

If the herniated disc irritates or presses on a nerve root (pinched nerve), it may cause pain, numbness, or tingling in the area of the body to which the nerve travels.