Cervical spondylosis is an age-related degeneration (‘wear and tear’) of the bones (vertebrae) and discs in the neck. It can progress to cause cervical radiculopathy (nerve root) or cervical myelopathy (spinal cord). However, it may be useful to be aware of the symptoms that suggest this may be happening, particularly as some of them may develop slowly..
Cervical radiculopathy
This occurs when the root of a nerve is pressed on or damaged as it comes out from the spinal cord in the neck (cervical) region. Although there are other causes of radiculopathy, cervical spondylosis is a common cause.
Degenerative changes to the joints around the vertebrae and osteophyte formation produce areas of narrowing which may nip the nerve. Another cause is a prolapsed disc. This is sometimes called a ‘slipped disc’ although the disc does not actually slip. What happens is that part of the inner softer area of the disc bulges out (prolapses) through a weakness in the outer harder part of the disc. This presses on the nerve as it passes out between the vertebra (see diagram).
As well as neck pain, symptoms of radiculopathy include loss of feeling (numbness), pins and needles, pain and weakness in parts of an arm or hand supplied by the nerve. These other symptoms may actually be the main symptoms rather than neck pain. There may be shooting pains down into the arm. The symptoms are usually worse in one arm but may affect both. The pain may be severe enough to interfere with sleep. The lower cervical vertebrae are the usual ones affected, causing these symptoms in the arms. However, if the upper vertebrae are involved, the pain and numbness occur at the back and the side of the head.
Your doctor may suspect a radiculopathy if you have the typical symptoms. A doctor’s examination may show changes to the sensation, power and tendon reflexes to areas of the arm supplied by the affected nerve. You may then be referred to a specialist for further tests. These may include an MRI scan which will show whether the nerve roots are being pressed on.
Treatment will depend on how severe the pressure and damage are. In many cases the symptoms settle over time. A course of physiotherapy or a neck collar used for a prescribed period may help. However, in some situations, endoscopy may be recommended which aims to relieve the pressure on the nerve.
Cervical myelopathy
This occurs when there is pressure on or damage to the spinal cord itself. Again, cervical spondylosis is a common cause of this condition, as the degenerative changes to the vertebra can narrow the canal through which the spinal cord passes. A prolapse of a cervical disc can also cause myelopathy if the prolapse is into the central canal of the vertebra. This may happen suddenly or develop over a period of time. There are various other rare causes of cervical myelopathy. For example, a tumour or infection that affects this part of the spinal cord.
As the spinal cord is made up of groups of nerve fibres carrying messages to the brain from the rest of the body, pressure on these nerves in the neck region can produce symptoms from several parts of the body.
The symptoms of a cervical myelopathy may include:
- Difficulties with walking. For example, the legs may feel stiff and clumsy.
- Changes to the sensation of the hands. For example, it may be difficult to grip objects, sign properly, have a tendency to drop things.
- Problems with your bladder. For example, you may experience problems with emptying your bladder, or incontinence.
A doctor’s examination may show changes to the sensation, power and tendon reflexes to the legs and arms. X-Rays and MRI of the cervical spine are advised. This will show how the spinal cord is affected. Early endoscopic decompression is advisable to preserve the cord function.
