The spinal cord is a collection of nervous tissue connecting the brain to the body. The spinal cord is surrounded for most of its length by the bones (vertebrae) that form the spine, and which protect the soft spinal cord from injury. The cord runs through the oval shaped opening in each vertebra. The vertebrae are stacked on top of one another and are separated by spongy discs that act as shock absorbers between each vertebra.
The spinal cord is divided into four sections: cervical, thoracic, lumbar and sacral. There are 31 pairs of spinal nerves that connect with the spinal cord through nerve roots, which extend from the spinal cord from either side of the spinal column. Each spinal nerve relates to a different section of the body.
The spinal nerves are:
- 8 in the cervical vertebrae
- 12 in the thoracic vertebrae
- 5 in the lumbar vertebrae
- 5 in the sacral vertebrae
- 1 coccygeal nerve