slipped disc This applies to an abnormality of an intervertebral disc in the spine. These discs are cushions of cartilage acting as shock absorbers between the bodies of the vertebrae that comprise the spinal column. They are therefore subject to considerable pressure, especially those in the lumbar spine, and these pressures are increased when a person lifts heavy weights. The discs are firmly fused to the vertebral bodies above and below, and the popular term is misleading — in suggesting that they are mobile structures that could slip out of place, and by implication could be ‘put back’ by manipulation or surgery. Rather, the discs can degenerate, a process that can be accelerated by repeated strains. Degenerated discs protrude and can press on spinal nerve roots or on the spinal cord, causing pain, with associated muscular spasm and sometimes weakness of the muscles of the arm, or of the leg, according to whether cervical or lumbar discs are affected. Such protrusions may require surgical removal. Only occasionally does acute injury tear part of an abnormal disc and release a loose fragment; this also may compress nervous structures and need to be removed.

Bryan Jennett

slipped disc, rupture or herniation of an intervertebral disc. These discs separate and cushion the vertebrae, the segments of the spinal column. They are composed of an outer rim of fibrous connective tissue and a gelatinlike inner core. If the fibrous rim breaks the core may leak into the spinal canal, resulting in severe pain that is aggravated by bending, straining, or coughing. Material from the disc may press on spinal nerves and cause numbness or tingling, weakness, or paralysis in the area of the body enervated by those nerves. Slipped discs occur as a result of severe strain or without any apparent stress at all. They are most common in the lower back and neck. Treatment consists of bed rest, usually with a hard board placed beneath the mattress, local application of heat, and the administration of muscle relaxants to relieve spasms. If natural healing fails to occur surgery may be required to remove the disc, and the affected vertebrae fused to keep them from rubbing together.

slipped disc (prolapsed intervertebral disc) Protrusion of the soft, inner core of an intervertebral disc through its covering, causing pressure on the spinal nerve roots. It is caused by a sudden mechanical force on the spine. It causes stiffness and sciatica. There are various treatments available.

slipped disc (also slipped disk) • n. a vertebral disc that is displaced or partly protruding, pressing on nearby nerves and causing back pain or sciatica. See disk noun sense 2.

slipped disc (slipt) n. see prolapsed intervertebral disc.