Normal cervical curvature

Our cervical spine has a certain degree of curvature, which is why we can move freely. People's normal cervical spine curvature is roughly the same, and the normal physiological curve is lordotic, so the pillow must be suitable for you, neither too high nor too low. It is precisely because the cervical spine can present a certain curvature that we can rotate in four directions, but people should protect their cervical spine to avoid compression and disease.

As the saying goes, “sit back and relax,” but that’s not the case. Under normal circumstances, the physiological curve of the cervical spine is lordotic. When lying in the supine position, if the pillow is too low and the head and neck are tilted backward excessively, the lordotic curvature will increase. Not only will the muscles and ligaments in front of the vertebral body easily become fatigued due to excessive tension, but it may also cause chronic injuries. At the same time, the tissue behind the spinal canal can protrude forward into the spinal canal, increasing the pressure within the spinal canal; excessive backward tilt of the head and neck can also stretch the spinal canal, causing the spinal cord and nerve roots within the spinal canal to become relatively shorter, making symptoms more likely to occur under the influence of other factors. If the pillow is too high and the head and neck are bent forward excessively, the muscles and ligaments behind the vertebrae may be easily strained, causing or aggravating cervical spondylosis.

Under normal circumstances, the human cervical spine has a certain curvature, which is specifically manifested as a forward bulge. However, due to some adverse external factors, it is easy to cause the physiological curvature of the cervical spine to become straight. These adverse external factors mainly include acute neck sprain, bad living habits and working posture, and cervical and shoulder myofibromyitis.

The normal range of motion of the neck is as follows: flexion 35°~45°, extension 35°~45°, left and right lateral flexion 45°, left and right rotation 60°~80°.

When the human body is sitting or standing, the neck appears to be straight when viewed from the side, but the cervical vertebrae surrounding it are not straight, but have an arc that bulges forward in the middle. This forward arc-shaped protrusion is medically known as the physiological curvature of the cervical spine. On X-rays, along the course of this curvature, a continuous smooth arc-shaped curve at the posterior edge of each cervical vertebra is called the physiological curve of the cervical spine. The normal value is 12±5mm. The measurement method is to draw a straight line from the posterior superior edge of the odontoid process to the posterior inferior edge of the seventh cervical vertebra. The maximum distance from the highest point of the arc to this straight line is the value of the cervical curve size.

The formation of cervical curvature is caused by the fact that the cervical 4-5 intervertebral disc is thick in front and thin in the back, which is a physiological need of the human body. It can enhance the elasticity of the cervical spine, play a certain role in buffering vibrations, and prevent brain damage. At the same time, it is also the normal anatomical and physiological requirement of important tissues such as the cervical spinal cord, nerves, and blood vessels. Whenever there is trauma, degeneration or poor posture, it can not only cause changes in the physiological curvature of the cervical spine, but also cause corresponding pathological changes, resulting in clinical symptoms and X-ray changes.

This cervical spondylosis cannot be ignored. It can cause soreness and pain in your shoulders, neck and upper limbs, and numbness in your fingers. "It can even cause symptoms such as dizziness, headache, nausea, blurred vision, unsteady walking, and urinary and bowel disorders."

Regardless of age, middle-aged or young, more and more people are suffering from this disease. There are three main factors that lead to cervical spondylosis: First, long-term computer operation and desk work have damaged the normal curvature of the cervical spine. Second, when people reach middle age or old age, their metabolic function declines, causing bone hyperplasia or calcification in the cervical spine, which affects the circulation of qi and blood and makes the neck more prone to pain. Third, caused by trauma: In addition to accidental neck injuries, incorrect posture during exercise; "whiplash injury" caused by the neck moving forward and backward in an instant when braking; inappropriate height of the pillow, or cold neck, etc., can all cause neck pain and inconvenience in movement.

In addition, the curvature of a normal cervical spine is backward, while the connected thoracic vertebrae is forward, which is a very reasonable distribution. However, because we often work with our heads down and lift heavy objects, the cervical spine is pulled and causes the cervical joints to loosen, the gaps between the joints to increase, and the curvature of the cervical spine to "distort", which can naturally cause neck and shoulder pain.