The lumbar curve is more marked in the female than in the male it begins at the middle of the last thoracic vertebra, and ends at the sacrovertebral angle. Lateral lumbar X-ray of a 34-year-old male This inward curve is known as a lordotic curve. The upper cervical spine has a curve, convex forward, that begins at the axis (second cervical vertebra) at the apex of the odontoid process or dens and ends at the middle of the second thoracic vertebra it is the least marked of all the curves. The curves allow the human spine to better stabilize the body in the upright position. The vertebral column is curved in several places, a result of human bipedal evolution. The combined region of the thoracic and lumbar vertebrae is known as the thoracolumbar division, or region.

Coccyx: 4 (3вЂ“5) (fused) vertebrae (Tailbone).

Individual vertebrae are named according to their region and position. The spinal nerves leave the spinal cord through these holes. In between each pair of vertebrae are two small holes called intervertebral foramina. These restrict the range of movement possible, and are joined by a thin portion of the neural arch called the pars interarticularis. The spinous processes of the cervical and lumbar regions can be felt through the skin.ДЄbove and below each vertebra are joints called facet joints. The spinous process comes out the back, one transverse process comes out the left, and one on the right. Two transverse processes and one spinous process are posterior to (behind) the vertebral body.

The vertebral arch is formed by a pair of pedicles and a pair of laminae, and supports seven processes, four articular, two transverse, and one spinous, the latter also being known as the neural spine. Because the spinal cord ends in the lumbar spine, and the sacrum and coccyx are fused, they do not contain a central foramen. Together, these enclose the vertebral foramen, which contains the spinal cord. The vertebral arch is posterior, meaning it faces the back of a person. There are ligaments extending the length of the column at the front and the back, and in between the vertebrae joining the spinous processes, the transverse processes and the vertebral laminae.ДЄ typical vertebra consists of two parts: the vertebral body and the vertebral arch. One study of 908 human adults found 43 individuals with 23 pre-sacral vertebrae (4.7%), 826 individuals with 24 pre-sacral vertebrae (91%), and 39 with 25 pre-sacral vertebrae (4.3%). The number of those in the cervical region, however, is only rarely changed, while that in the coccygeal region varies most.

There are seven cervical vertebrae, twelve thoracic vertebrae and five lumbar vertebrae. The articulating vertebrae are named according to their region of the spine. The upper 24 pre-sacral vertebrae are articulating and separated from each other by intervertebral discs, and the lower nine are fused in adults, five in the sacrum and four in the coccyx, or tailbone. In a human's vertebral column, there are normally thirty-three vertebrae. The number of vertebrae in a region can vary but overall the number remains the same.

Lumbar spine anatomy