The vertebrae are the bones that form the spine . Their function is twofold : to protect the spinal cord , and to support the body . Damage to the vertebrae or intervertebral discs, which separate the vertebrae from each other, can cause health problems (e.g. herniated discs ) .
What are Vertebrae?
The spine is made up of 33 overlapping bones , i.e. the vertebrae. The vertebrae are distinct according to their position : there are therefore five lumbar vertebrae, twelve thoracic vertebrae and seven cervical vertebrae . In addition to these, there are five other vertebrae that are fused together, and are located in correspondence of the sacrum .
In the anterior part, each vertebra is formed by a vertebral body, while in the posterior part there are neural arches that delimit the intervertebral foramen . It is a cavity that allows the passage of the spinal cord . The neural arches of the vertebrae are joined in their posterior part to form the spinous process. A transverse process protrudes from each of the arches. The neural arches are divided into several parts: the lamina , between the spinous process and the transverse process, and the peduncle , between the transverse process and the vertebral body.
The articular facets are located at the meeting point of the lamina and peduncle , the two upper parts of a vertebra form an articulation with the two lower parts of the next vertebra. This structure may differ depending on the area of the spine considered.
The spinous process of the cervical vertebrae , for example, is bifid and in the transverse processes there is a hole in which the vertebral artery and vein flow. The first cervical vertebra has no body, while the second is characterized by the odontoid process. Processes more than other vertebrae are also found in the case of lumbar vertebrae. The thoracic vertebrae instead have facets that allow their articulation with the ribs. Finally, the vertebrae of the sacrum have a particular shape that derives from their fusion and are equipped with holes that allow the passage of the anterior and posterior branches of the spinal nerves .
What are the Vertebrae for?
All vertebrae perform three basic functions , regardless of their position. The vertebral body serves to support weight , resisting compression and load . The vertebral arches are the canal through which the spinal cord flows. The transverse processes constitute the junction points between the vertebrae and the muscles .