A Flexible Protective Column - The Anatomy Of Your Back: Back Pain

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A flexible, protective column

The cylindrical vertebral bodies and the disks between them form only part of the spinal column. The portions of the vertebrae behind the bodies — known as posterior elements because they are located at the rear of the spine, the part just under the skin on your back — fit together as well. The result is a tube of bone and ligament that extends from your head to your pelvis and serves as a conduit for the spinal cord and the nerve roots that extend from the bottom of the cord.

The posterior elements include the bony processes that project from the vertebrae. These processes play an important role as stabilizers of the spine. Each vertebra normally has seven: a spinous process down the middle of the back, two superior (upper) and two inferior (lower) articular processes, and right and left transverse processes on the sides. The articular processes mesh with those of adjacent vertebrae to form a series of small connections, called facet joints, which give the spine additional stability and also allow the type of motion normally possible between vertebrae.

Last updated:	January 23, 2007