Cervical spondylosis refers to an abnormal condition of the structural elements of the neck. These elements include cartilage, ligaments and bones. Although it has yet to be recognized, as covered in my book called The Downside of Upright Posture, cervical spondylosis may play a role in multiple sclerosis, Alzheimer’s and Parkinson’s disease, as well as other neurodegenerative diseases, due to its impact on blood and CSF flow in the brain. In particular, degenerative conditions of the cervical spine, cervical spondylosis can lead to chronic ischemia, edema and hydrocephalic type conditions in the brain. They can also cause turbulance, backjets and standing waves of cerebrospinal fluid (CSF) to form in the basal cisterns of the brain. The basal cisterns are wells filled with CSF that surround and protect the brainstem.
As an aside, cervical spondylosis and abnormal conditions of the upper cervical spine may also play a role in neurodegenerative diseases of the cord such as amyotrophic lateral sclerosis. I will cover neurodegenerative diseases of the cord separately as this site develops.
The general term spondylosis literally means an abnormal condition of the spine. Spondylo means spine and osis means an abnormal condition of. It refers to an abnormal condition of any area of the spine associated with degeneration of the structural elements and labeled according to the area affected. There are several causes of degeneration of the spine, such as aging, wear and tear (micro trauma) and accidents (macro trauma). Osteoarthritis, which is another term for spondylosis is due to dry, degenerated and inflamed joints of the spine. Degenerated and herniated discs are, likewise, a type of spondylosis, as is degeneration of the joint capsules or ligaments of the spine.
In an xray the denser the structure the whiter it appears, the less dense appears grey to black. In the picture below the bones of the spine are whiter in color and the cartilage called discs and the connective tissues are shades of gray or black. The bones that make up the segments of the spine are called vertebra. Except for the first segment of the spine beneath the skull called atlas or C1, all the other segments of the spine are separated by discs. This lateral xray of the cervical spine is an example of a spine without cervical spondylosis.
The x-ray below is an example of cervical spondylosis associated with bone spurs called osteophytes and narrow degenerated discs in the lower vertebra.
Certain conditions are associated with spondylosis such as scoliosis and kyphosis due to abnormal curvatures creating greater stress and therefore wear and tear. Scoliosis and kyphosis affect the design of the spinal canal, which can cause functional stenosis. Scoliosis is typically diagnosed early on but adults can get it later in life due to degeneration of the bones, cartilage and connective tissues of the spine. Although these conditions can affect all areas of the spine they can also lead to cervical spondylosis.
Stenosis comes from the Greek term stenos meaning narrow. It is a condition in which the spinal canal, which houses the spinal cord or the openings on each side of the canal for the nerve roots to exit are too narrow, which can compress the cord and/or nerve roots. Stenosis can be due to congenital design problems, but more often it is the result of spondylosis due to aging and injuries to the bones and connective tissues of the spine. These tissues then invade the spine’s neurovascular tunnels, which are the spinal canal and intervertebral foramen (the openings where the nerve roots exit).