There are seven cervical vertebrae. Except cervical vertebra 1 and cervical vertebra 2, there are intervertebral discs between other cervical vertebrae. Together with the intervertebral disc between cervical vertebra 7 and thoracic vertebra 1, there are six cervical vertebrae. Each cervical vertebra consists of vertebral body and vertebral arch. The vertebral body is an oval column, which is connected with the vertebral arch to form a vertebral foramen. All vertebral foramen are connected to form spinal canal, and the spinal cord is included in it. There is a depression on the upper and lower edges of pedicle, which is called notch in medicine.
The upper and lower incisors form intervertebral foramen, from which the cervical nerve roots emanate. Usually, the cervical nerve only accounts for half of the intervertebral foramen, so it will not be squeezed. However, in the case of cervical dislocation, fracture, bone spur, ligament hypertrophy and other diseases, intervertebral foramen will become smaller or relatively smaller, nerve roots will be stimulated or compressed, and symptoms such as finger numbness and pain will appear.
There are seven protrusions on each cervical vertebra, the spinous process is the lower part of the protrusion, and its tail is mostly forked. Extending to both sides is the transverse process, which has a transverse process hole through which the vertebral artery passes. There are superior articular processes and inferior articular processes on both sides of the vertebral arch. The joint is nearly horizontal, the upper joint is backward and upward, and the lower joint is inward and downward, which is beneficial to the flexion and extension of the cervical spine.
The cervical vertebra also has a special joint which is different from other vertebral bodies, called uncinate process joint. It consists of uncinate process at the back of vertebral body and slope at the lower side of vertebral body. This joint can prevent the intervertebral disc from protruding to the outside and the back, but when it proliferates due to degeneration, it can affect the blood circulation of its lateral vertebral artery and compress its posterior spinal nerve roots.
What are the characteristics of the seventh cervical vertebra? The seventh cervical vertebra has the same structure as the ordinary cervical vertebra except that the spinous process extending backward is very long. Because its spinous process is very long, the end is not bifurcated and it is nodular, and the process is under the skin, so it is called carina. It rotates with the rotation of the neck, which is a sign to identify the spinal ordinal number in clinic.