What is the significance of trauma to the head and neck in the development of cervical spondylosis?

     Trauma to the head and neck has a clear relationship with the occurrence and development of cervical spondylosis, and can have different effects at different stages depending on the location and degree of injury.      (1) Vertical compression violence often causes compression fractures of the cervical vertebrae, resulting in the disappearance of cervical physiological forward flexion or reduction of curvature, increased stress on the intervertebral disc of the damaged segment, and accelerated cervical degeneration. (2) Cervical spine injury can have different effects on patients at different stages. For people with existing cervical degeneration and cervical spinal stenosis, cervical spine injury can cause the following three conditions.      Acute anterior central spinal cord syndrome: sudden paralysis of the extremities due to blockage of the anterior central spinal cord artery after compression, resulting in ischemia in the front of the spinal cord. This injury is seen in hyperflexion when the bony flank compresses the anterior central spinal artery in front of the spinal cord.      Acute sulcus arteriosus syndrome: When the cervical spine is hyperflexed, the posterior edge of the vertebral body is compressed by the bony redundancy or protruding disc tissue on the sulcus artery, a branch of the anterior central spinal cord artery. The main manifestation is limb paralysis with heavy upper limbs and light lower limbs.      Acute central spinal cord canal syndrome: In hyperextension injury, the degenerated and thickened ligamentum flavum protrudes into the spinal canal, causing edema and hemorrhage around the central spinal cord canal. It is characterized by paralysis of the upper extremity more than the lower extremity, loss of warmth and pain sensation, and widening of the shadow of the anterior intervertebral space on x-ray.      (3) Violence resulting in cervical disc herniation: manifests as symptoms of nerve damage of varying degrees and neck pain.      (4) Tearing of the anterior longitudinal ligament: although it does not directly damage the spinal cord and nerve roots, it accelerates the degeneration of the vertebral segment of the damaged segment due to causing instability of the cervical spine. Many clinical patients with cervical spondylosis have a history of early cervical trauma.      (5) Transient cervical dislocation: hyperflexion violence causes anterior dislocation of the cervical vertebrae, and when the violence disappears, the dislocated vertebrae can return to their original position. However, due to local soft tissue injury, cervical instability exists at the injury site, and if not treated in a timely manner, cervical instability is aggravated in the future and bone growth at the posterior edge of the vertebral body constitutes an irritation and compression of the spinal cord.