The vertebral column consists of 32 or 33 individual and interlocking bones known as the vertebrae (singular: vertebra) which are stacked upon each other vertically. The vertebral column is generally classified into different segments– the cervical region, thoracic region, lumbar region, sacrum, and coccyx. In between the adjacent vertebra lies the cartilaginous discs known as the intervertebral discs. These are present throughout the vertebral column’s length, except in the sacrum and coccyx, which are fused vertebral structures in the lowermost regions.

According to a journal published by Mahadevan (2018), overall, there are 23 intervertebral discs with the last disc situated at the lumbosacral junction and the first disc being located between the C2 and C3 vertebral bodies. Collectively, these intervertebral discs compose approximately one-third of the vertebral column’s height. Furthermore, these discs are thickest in the lumbar region and thinnest in the upper thoracic region.

Mahadevan (2018) further stated that the vertebral column, along with the sternum and 12 pairs of ribs, makes up the trunk’s skeleton. It is also a strong and flexible midline structure. It protects and supports the skull as well since the skull is located at the upper end of the vertebral column.

When the vertebral column is viewed upright or superiorly, one can observe a space or gap in the middle portion. This “space” is known as the vertebral foramen, which serves as the passageway from the base of the skull to the lower back neural arch, which is known as the coming together of two laminae.

The cervical vertebra has spinous processes located posteriorly at the arch’s center point. It also has transverse processes that extend posteriorly and laterally from the vertebral body. It also contains the intervertebral foramina that serves as a passageway for spinal nerves to exit and then enter the spinal cord. The cervical vertebra also has facets or spaces which come in contact with the skull. Its superior facet is the atlas, which is also known as the C1, while its inferior facet is the axis, which is also known as the C2.

Jones (2020) stated that the seven cervical vertebrae in the human body have three distinguishing factors:

1. Bifid spinous process – At its distal end, the spinous process bifurcates. However, some cervical vertebrae do not have this feature. These are the C1, which has no spinous process, and the C7, which may not bifurcate due to the longer length of its spinous process.

2. Transverse foramina - These are the spaces or passageway of the vertebral artery towards the brain.

3. Triangular vertebral foramina – The C1 and C2 are specialized cervical vertebrae because they allow the head movement to occur.

It is also important to note that the cervical spine has seven vertebrae, known as the C1-C7.

Next, we shall tackle the thoracic vertebrae. Overall, there are 12 thoracic vertebrae which are classified as T1-T12. This is the most number of vertebrae. These vertebrae are generally medium-sized and decrease in size from inferior to superior. They articulate with the ribs, which is how they produce the bony thorax. Mahadevan (2018) stated that the thoracic vertebrae contains facets on their transverse processes. These facets articulate with the tubercles of the ribs. Moreover, typically, the thoracic vertebrae contain long spinous processes that slope downwards.

Consequently, the lumbo-sacro-coxal vertebrae, or simply the lumbar vertebrae are the largest vertebral column, which are specialized to support the torso’s weight. These are numbered from L1-L5. Unlike the other vertebrae, they do not have transverse foramina or bifid spinous processes. They contain a triangular-shaped vertebral foramen. Moreover, needle access to the spinal canal and spinal cord, such as epidural anaesthesia and lumbar puncture, usually happens in the lumbar vertebrae because the size of the lumbar vertebrae is ideal for that process.

The next parts that we are going to discuss are the sacrum and coccyx. The sacrum has 5 vertebrae like the lumbar but they are fused together. Attached to the lateral walls of the sacrum are the facets for articulation with the pelvis. On the other hand, the coccyx is a small semi-fused bone that articulates with the sacrum’s apex. The coccyx are also terminal vertebrae (3-4) and are located at the terminal end of the vertebral column. It has no vertebral canal since it does not have vertebral arches.