Understanding How Your Back Works
The back (spine) is made up of the bones (vertebrae), spinal cord, nerves, muscles, ligaments, and the system that carries blood (blood vessels).? The vertebrae of the back protect the spinal cord.?
- The top seven vertebrae make up the neck (cervical spine) and begin at the base of the head.
- There are twelve vertebrae making up the upper and middle back (thoracic spine).?
- The bottom five vertebrae of the spine make up the lower back (lumbar spine). The sacrum bone and tailbone (coccyx) are at the very bottom of the back.
In the healthy back, there is a disc filled with fluid between each vertebra. The disc helps to cushion the vertebrae from moving together under the weight of the body.? Some of the discs also allows the vertebrae to turn and move front-to-back, side-to-side and left-to-right.
The discs between the vertebrae have a strong outer ring (annulus fibrosis). The outer ring helps keep the disc’s soft center (nucleus pulposus) in place.?