The spine consists of 24 vertebrae, which in turn are composed of a vertebral body and a vertebral arch.
Anatomy
The anatomy of the vertebral bodies reflects the special function of the spinal column, which includes on the one hand the protection of the spinal cord and on the other hand as an important element the stability of the complete skeleton with simultaneous mobility of the upper body. The spinal column is made up of a total of 24 vertebral bodies, whereby seven cervical vertebrae, twelve thoracic vertebrae and five lumbar vertebrae are distinguished. Each vertebral body is connected to the next via an intervertebral disc, whereby the comprehensive ligamentous apparatus additionally holds the entire spinal column together.
Especially the vertebral bodies are surrounded by the anterior and posterior longitudinal ligaments. The vertebral arches with the spinous process are connected to the back of the vertebral bodies. Due to the fact that the load acting on the vertebral bodies increases from the first cervical vertebra to the last lumbar vertebra, the size of the vertebral body also increases.
The bone marrow of the vertebral body contributes a high proportion to blood formation. The special features of the cervical vertebral bodies are that they are relatively small and narrow and that they have vertical hooked processes and lateral rib rudiments, which now serve as a guiding structure for the right and left spinal artery and nerves. In the thoracic vertebral bodies, it is noticeable that the anterior ones are lower than the posterior ones and have the cartilaginous joint sockets for the ribs on the sides. The lumbar vertebral bodies are characterized by their relatively enormous size.
Structure
A common feature in the structure of all almost cylindrical vertebral bodies, with the exception of the first and second vertebrae, is the compact bone frame, which surrounds the medullary cavity of the vertebral body, which consists of spongy, delicate bone beams called “cancellous bone”, on all sides. Typical for cancellous bone of the vertebral body are the strongly pronounced vertical bone beams, which is due to the fact that their growth is stimulated more by longitudinal loading than by horizontal loading. On the upper and lower sides of the vertebral body there are an upper and a lower cover plate, which is covered by the intervertebral disc and connected to the next vertebra.
