For unknown reasons, some people develop degenerative disc disease in the spine. This means one or more intervertebral discs lose their mechanical strength and begin to deteriorate. In doing so, they no longer are able to cushion the forces between opposing vertebrae and as a result the discs begins to herniate, or bulge. As the bulge pushes onto spinal roots or the spinal cord, symptoms begin. Usually when symptoms are severe, surgery is recommended to remove the disc.
Causes
It is not known why people get degenerative disc disease. According to Centra Care Library, scientists believe it may be an autoimmune phenomenon, or may have a genetic or environmental substrate. They also report that smoking cigarettes and performing vigorous repetitive activity seems to have some involvement.
Individual Variability
Severity and symptoms of degenerative disc disease vary from individual to individual. A person can be completely asymptomatic for years according to the Mayfield Clinic. Others with degenerative disc disease suffer debilitating pain. Such pain can appear suddenly or may manifest gradually. Degenerative disc disease usually starts to manifest in the person's 20s or 30s. Persons in their 60s usually do not have the disease.
Onset
Pain is the main symptom in persons with degenerative disc disease. In many cases, the pain is initiated by a traumatic event, such as a blow to the head. Sometimes this trauma causes pain that seems unrelated to the trauma. A seemingly minor trauma can trigger back pain, and sometimes the pain will manifest on its own without a trigger. (ref 1) As protruding disc degenerates further, it presses on the spinal roots and produces radiculopathy, or symptoms of nerve damage. Sometimes it presses on the spinal cord and produces myelopathy, or symptoms of central nervous system damage. (ref 5)
Symptoms
The Merck Manuals Online Medical Library states that symptoms of degenerative disc disease can vary from one spinal level to the next. Radiculopathy and myelopathy can occur at any level. The degree of pain is worsened as disc degeneration progresses and causes even more pressure on the nervous tissues. The British Medical Journal, 2001, states that with cervical disc degeneration, pain and parasthesia symptoms occur in the head, neck, upper body and limbs, back and legs. Symptoms of damage to the sympathetic chain also can appear, as can hemiparesis and partial diaphragm paralysis. When disc degeneration affects lower vertebrae, the symptoms become limited to the lower regions of the body. However, degeneration of higher or lower vertebral discs can produce problems with walking. Usually the more deteriorated the disc, the more severe the symptoms.
Treatment
Since the primary cause of pain and other symptoms of degenerative disc disease are due to disc bulging, surgery is usually recommended to remove the disc. A discectomy, according to the Mayfield Clinic can be performed from either the anterior or posterior body surfaces. Once the disc is removed, the spinal segments are fused so that the segments no longer move.
References
- Centra Care Health Library
- Mayfield Clinic: Degenerative disc disease
- "British Medical Journal"; Degenerative cervical disc disease causing cord compression; P. Bently, et. al.; February, 2001
- "Journal of Neurology, Neurosurgery and Psychiatry"; Midcervical central cord syndrome: numb and clumsy hands; M. Nakajima and K. Hirayama; June, 1995
- The Merck Manuals: Compression of the Spinal Cord
