Spondylosis is a term referring to degenerative osteoarthritis of the joints between the center of the spinal vertebrae and/or neural foramina. If this condition occurs in the zygapophysial joints, it can be considered facet syndrome. If severe, it may cause pressure on nerve roots with subsequent sensory and motor disturbances, such as pain, paresthesia, or muscle weakness in the limbs.
When the space between two adjacent vertebrae narrows, compression of a nerve root emerging from the spinal cord may result in radiculopathy (sensory and motor disturbances, such as severe pain in the neck, shoulder, arm, back, and leg, accompanied by muscle weakness). Less commonly, direct pressure on the spinal cord (typically in the cervical spine) may result in myelopathy, characterized by global weakness, gait dysfunction, loss of balance, and loss of bowel and/or bladder control. The patient may experience a phenomenon of shocks (paresthesia) in hands and legs because of nerve compression and lack of blood flow. If vertebrae of the neck are involved it is labelled cervical spondylosis. Lower back spondylosis is labeled lumbar spondylosis.
Spondylosis can affect a person at any age; however, older people are more susceptible.
Lhermitte sign: feeling of electrical shock with neck flexion;
Reduced range of motion of the neck, the most frequent objective finding on physical examination MRI testing. This test is non-invasive and provides the only definitive positive diagnosis.