Spine

The column of bones and cartilage that extends from the base of the skull to the pelvis, enclosing the spinal cord and supporting the trunk and head. The spine is made up of 33 roughly cylindrical vertebrae. Each pair of adjacent vertebrae is connected by a facet joint, which stabilizes the vertebral column. Between each pair of vertebrae lies a disc-shaped pad of cartilage called an intervertebral disc (see disc, intervertebral). These discs cushion the vertebrae during movement. The vertebrae are bound together by 2 ligaments running the length of the spine and by smaller ligaments between each vertebra. Attached to the vertebrae are several groups of muscles, which control movement of, and help to support, the spine.