Cervical movement is performed by discs and joints between the vertebrae. Degeneration of cervical spine starts in the intervertebral discs, resulting in secondary changes to other adjacent joints. This process in the spine is defined as ‘spondylosis’. Cervical spondylosis generally occurs between the most moving cervical vertebrae (C4-5, C5-6, C6-7) and in middle-aged or elderly people. This disease is the most common cause of progressive spinal cord and nerve root compression. Restriction of neck movements, pain or neurological damages (radiculopathy or myelopathy) can occur.

Small bony growths called osteophytes occur around spinal canal and nerve root canal in spondylosis. Osteophythic extensions alone can be symptomatic and cause narrowing of spinal canal. It can cause narrowing of diameter of spinal canal when located in the midline or cause root compression by extending into where the roots arise. Loss of movement develops between the vertebrae involved at advanced stages which results in loading an abnormal stress on adjacent spinal segments. As a result of this interaction degenerative changes occur involving multiple levels such as spondylosis or stenosis. A cervical spine with spondylosis is more exposed to traumatic impacts and can cause major injuries even with minor traumas.

The factors causing cervical disc diseases can include ageing, overloading and trauma, long-term working in abnormal posture, genetic causes, smoking, vascular diseases and diabetes, or chronic rheumatic diseases. Cervical spondylosis results in pain in the neck, shoulders and arms by compressing nerve roots. The pain can radiate from the arm into the palm by specific distribution of the nerve root under compression. If cervical disc hernia compresses the spinal cord, problems with walking, spasticity (increased muscle tone) and urinary incontinence can occur.

Diagnosis

The diagnosis of patients with cervical spondylosis involves a detailed physical examination including a neurological examination. The bony changes to spine can be viewed by radiography and computerized tomography (CT). Magnetic resonance (MRI) imaging is particularly useful to demonstrate the compression on the nerves. With EMG, the levels of complaints can be determined especially in preoperative planning.

Treatment

Initial treatment is usually conservative; patient education, cervical bracing, physical therapy exercises, and nonsteroid anti-inflammatory drugs are the most common treatment methods. The use of neck bracing can reduce cervical movements and relieve the compression. Physical therapy exercises will help strengthening the muscles and increasing in movement range. Injection is another treatment option, can be used to soothe the complaints for a certain period of time.

If the complaints of the patient persist, or if neurological findings are found or aggravated despite conservative treatment, a surgical intervention will be considered. The surgical intervention to be performed depends on the pathology causing the current state of the patient. The most commonly used surgical approaches are anterior (from the front) and posterior (from the back).

Anterior approach: Cervical vertebrae are accessed by entering from the front of the neck. The herniated disc between the vertebrae and the bony spurs causing compression on the spinal cord are removed. This is called corpectomy. The resulting space can be supported by an implant or bones from the patient or artificial bone grafts.

Posterior approach: It is based on removal of posterior membranes of vertebrae (laminectomy) and relief of spinal cord canal. It is performed for stenosis of spinal canal along one or more levels. If required, posterior fixation would be performed with titanium screws to maintain the stability of spine after removal of back membranes.