Understanding the Pathophysiology of Cervical Spondylosis

spinal stenosis

Cervical Spondylosis is a multifaceted degenerative disease that is mostly seen in 95% of people with the age of 65. Primarily, men are more affected by this condition than women. The degeneration often attacks the facet joints and intervertebral discs in the spine which is responsible for the mobility and flexibility of the vertebrae. When osteophytes form in the vertebral discs, the diameter of the spinal canal may increase with an end result of developing complications that often leads to cervical myelopathy or cervical radiculopathy.

The changes that are presented in the cervical spine are ultimately responsible for the primary lesions visible in cervical spondylosis. Two mechanical factors are involved in the condition's pathogenesis. Abnormal forces exerted on the spinal cord and spinal column during abnormal movements is categorized under dynamic factors. Static factors on the other hand, include formation of bones spurs or osteocytes in the discs, hypertrophy, and disc herniation. In some rare cases, congenital canal stenosis may also be evident.

The start of degenerative changes in Cervical Spondylosis occurs in the disc space when the disc's protein composition is altered. During the alteration of the disc matrix, the molecular weight of the disc decreases. This happens when the ratio of kertin sulfate to chondroitin sulfate increases.

When the vertebral discs lose water in its contents, its height gradually decreases at the same time loses capability when it comes to axial loading. As the disc's weight decreases along with its height, the nucleus pulposus begins to shrink as loses more mucopolysaccharides, protein and water. As an effect of dehydration, the nucleus pulposus becomes prone to fragmentation. The vertebral discs then lose elasticity which results in neck stiffness and pain with twisting when moving about. These changes are the main pathophysiological factors that lead to Cervical Spondylosis.

When a compression of the spinal nerves in the neck is observed as a result of Cervical Spondylosis, a certain condition, medically termed as Cervical Spondylotic Myelopathy (CSM) occurs. The osteopathic changes observed in CSM are accompanied by thickening of the ligament which often results to canal stenosis. Some of the clinical presentations of CSM include hand and gait disturbances, clumsiness and weakness of hands and paresthesia.

On the contrary, narrowing of the spinal canal or the foramen due to Cervical Spondylosis then leads to the degenerative disease known as Cervical Radiculopathy. This condition is also described as nerve pinch, in layman's term. Pain felt in cervical radiculopathy is often described as sharp, like needles and pins pricking the skin.