Jason E. Smith MD

Spine Surgeon with Baton Rouge Orthopaedic Clinic 

Call Us:  225-924-2424

Additional Anatomy Info available on the BROC website.

Regions of the Spine

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.

Spinal Curvature

When viewed from the front or back, the normal spine is in a straight line, with each vertebra sitting directly on top of the other. Curvature to one side or the other indicates a condition called scoliosis.

When viewed from the side, the normal spine has three gradual curves:

The neck has a lordotic curve, meaning that it curves inward.
The thoracic spine has a kyphotic curve, meaning it curves outward.
The lumbar spine also has a lordotic curve.

These curves help the spine to support the load of the head and upper body, and maintain balance in the upright position. Excessive curvature, however, may result in spinal imbalance.

Anatomical Causes of Pain