In humans the vertebral column, also referred to as the spinal column, stretches from the base of the skull to the pelvis and consists of thirty-three vertebrae. These individual vertebrae are stacked one on top of another with cushioning provided by intervertebral discs. The vertebrae are divided into four sections when discussing human anatomy: cervical vertebrae; thoracic vertebrae; lumbar vertebrae; sacrum. The coccyx is the tailbone at the very base of the spinal column. Seven of the vertebrae are in the cervical region, twelve in the thoracic vertebral spine, five/six in the lumbar spine, five fused vertebra in the sacrum, and the last three in the coccyx. These are all abbreviated in medical terminology as C1-C7, T1-T12, L1-L5, and S1-S5. The cervical vertebrae are the smallest, and the lumbar vertebrae the largest in the spinal column.
The Cervical Spine
The cervical spine differs from the other spinal sections in that it is much more flexible and mobile. From the base of the skull to the top of the thoracic spine, the cervical spine has a backward C-shaped curve to it, referred to as a lordotic curve. If the cervical spine degenerates the curve can become problematically kyphotic, meaning that it has begun to curve forward and cause a person to stoop, such as in conditions like ankylosing spondylitis. The flexibility of the cervical spine can mean extra strain on the intervertebral discs in the neck, and the ligaments and muscles that support its structure. The cervical spine also has special openings in each vertebra through which the arteries supplying blood to the brain can pass through. These holes are called foramen and occur in the transverse process of the cervical vertebrae where the lamina joins the pedicle. Bone spurs, fracture, or degeneration in the cervical vertebrae can put pressure on these blood vessels and the nerves which also pass through gaps in the spinal column.