As people age, however, the discs undergo changes. They may dry out, thin, or crack. The soft cartilage core may bulge or herniate out through the fibrous outer portion of the disc. Degenerative disc disease is an umbrella term that describes these age-related processes.
Most people’s spinal discs degenerate over time. By the age of 35, approximately 30% of people will show evidence of disc degeneration at one or more levels. By the age of 60, more than 90% of people will show evidence of some disc degeneration. Degeneration itself is normal, and does not necessarily cause pain. Painless degeneration is just called degeneration. The term “degenerative disc disease” describes disc degeneration that causes pain and other symptoms.
Degenerative disc disease can cause pain, weakness or numbness. Exact symptoms vary depending on the location and type of disc degeneration. The primary symptoms of degenerative disc disease include sharp and /or chronic pain in the back and neck.
As the discs undergo change, the body may react and develop bony growths called bone spurs. In severe cases, these bone spurs may take up room needed by the spinal cord and surrounding nerves to move freely in the spinal canal.
If the nerves in the spine become compressed (pinched), patients may experience weakness in the arms or legs and numbness in the legs. Compression of the spinal cord itself is referred to as myelopathy. A patient with myelopathy may have difficulty walking, and may even experience loss of bladder and bowel control.
Causes and Risk Factors
Degenerative disc disease is usually associated with the normal effects of aging. The discs between the bones of the spine are made up of cartilage, fibrous tissue, and water. With age, these discs can weaken and may flatten, bulge, or break down.