The dynamics and supportive properties of the human spine are provided by:
- an intricate network of blood vessels
- countless specialized nerve endings
- hundreds of small nerve fibers which connect to structures of the spine
- more than 220 specialized ligaments
- greater than 120 individual muscles
- over 100 intricate joints
- 34 vertebrae
- 24 presacral vertebrae -----movable
- 5 sacral and 3-5 coccygeal vertebrae------non-moveable
- 31 pairs of spinal nerves
- 23 intervertebral discs
The human spinal column provides flexibility for movement, support for weight bearing and protection of nerve fibers. The spinal column surrounds and protects the spinal cord, which is the main pathway of communication between the brain and the rest of the body. The spinal column also protects the nerve roots and part of the autonomic nervous system.
The spine has three major types of joints:
The vertebral column consists of 24 presacral (moveable) vertebrae
7 cervical vertebrae
12 thoracic vertebrae
5 lumbar vertebrae
The sacrum and coccyx are composed of fused vertebrae and are also considered part of the spinal column.
The cervical vertebrae are the most mobile of the 24 presacral spinal vertebrae.
The 12 thoracic vertebrae articulate with 12 pair of ribs. The thoracic spine is designed for a minimum of movement, thus providing protection for the internal organs.
The large stocky lumbar vertebrae are designed to support the weight of the body.