Humans are born with 33 separate vertebrae. By adulthood, we typically have 24 due to the fusion of the vertebrae in the sacrum.
- The top 7 vertebrae that form the neck are called the cervical spine and are labeled C1-C7. The seven vertebrae of the cervical spine are responsible for the normal function and mobility of the neck. They also protect the spinal cord, nerves and arteries that extend from the brain to the rest of the body.
- The upper back, or thoracic spine, has 12 vertebrae, labeled T1-T12.
- The lower back, or lumbar spine, has 5 vertebrae, labeled L1-L5. The lumbar spine bears the most weight relative to other regions of the spine, which makes it a common source of back pain.
- The sacrum (S1) and coccyx (tailbone) are made up of 9 vertebrae that are fused together to form a solid, bony unit.