Degenerative disc disease is characterized by the breakdown of the intervertebral discs — the soft discs that act as shock absorbers and provide flexibility to the spine. This condition is not a disease, but it is a common change that occurs with age. It is a common age-related change in which the wear and tear affects the spine, particularly the lower back and neck region. These changes may result in a number of conditions like back pain, neck pain, osteoarthritis, herniated discs, and spinal stenosis. As the changes apply pressure on the spine, nerve functions may be affected.
Symptoms of degenerative disc disease often differ depending on the individual. Some people may not experience any pain, while others may have intense pain that affects day-to-day activities. Severity and location of pain depends on the affected region of the spine. If the disc in the neck region is deteriorating, it may result in neck pain. If the disc in the lumbar region is affected, it may result in lower back pain or leg pain. People also complain of a tingling or numbing sensation in the leg. The pain may persist for a long time, with episodes of severe pain once in a while. Sitting may cause acute pain, as the pressure on the discs is greater in this position. Bending and twisting might also increase the intensity of the pain. The pain may start gradually over a period of time, or suddenly after an injury.
The most important causes of degenerative disc disease are the age-related changes:
- The water and protein content of the cartilage changes with age. Loss of fluid from the discs reduces their flexibility and affects the functioning. It reduces the distance between the vertebrae as the disc becomes thin. As the space between the vertebrae becomes narrow, small bony spurs may develop, which puts more pressure on the spinal nerve.
- The discs may develop small cracks on the surface with age. The jelly-like content of the disc may ooze out of the tear, or cause bulging of the disc.
The risk of developing these changes is greater in smokers and those who do strenuous physical activities. Obese people also have enhanced risk of developing degenerative disc disease. Degeneration may also be triggered by herniation of the disc, which often results from a sudden injury.