A slipped disc refers to an intervertebral disc of the spine that has lost its normal shape and/or consistency. The altered shape occurs when the disc’s soft inner material (nucleus pulposus) bulges or leaks out of its external fibrous covering (annulus fibrosus).¹ Several medical terms, such as herniated, ruptured, torn, bulged, or protruding disc may be used interchangeably with a slipped disc.

Herniated Disc Video 

A herniated disc occurs when material from a disc's inner core leaks out. Watch: Herniated Disc Video

Your intervertebral discs are spinal shock absorbers and help transfer loads evenly. When a slipped disc occurs, the entire motion segment—including the adjacent vertebrae, connective tissue, blood vessels, and nerves may be affected.² Slipped discs are more common in the lower back, followed by the neck.³

How a slipped disc occurs

The two most common causes for a slipped or herniated disc are³:

• Natural degeneration of the disc, which causes the nucleus pulposus to become less hydrated and weaken with age.

  Read: What Is Degenerative Disc Disease?

• Trauma to the disc, which may occur due to lifting a heavy load using incorrect posture or from external forces, such as, a whiplash injury.

Rarely, disorders of the connective tissue of the spine or alterations in the shape of the spinal vertebrae, such as short pedicles, may cause a slipped disc to occur.³