What is degenerative disc disease?
Degenerative disc disease is not really a disease but
a term used to describe the normal changes in your
spinal discs as you age. Spinal discs are soft,
compressible discs that separate the interlocking bones (vertebrae) that
make up the
spine. The discs act as shock absorbers for the spine,
allowing it to flex, bend, and twist. Degenerative disc disease can take place
throughout the spine, but it most often occurs in the discs in the lower back
(lumbar region) and the neck (cervical region).
See a picture of
the spine and the
discs in your spine .
The changes in the discs can result in back or
neck pain and/or:
These conditions may put pressure on the spinal cord and
nerves, leading to pain and possibly affecting nerve function.
What causes degenerative disc disease?
As we age,
our spinal discs break down, or degenerate, which may result in degenerative
disc disease in some people. These age-related changes include:
- The loss of fluid in your discs. This reduces
the ability of the discs to act as shock absorbers and makes them less
flexible. Loss of fluid also makes the disc thinner and narrows the distance
between the vertebrae.
- Tiny tears or cracks in the outer layer
(annulus or capsule) of the disc. The jellylike material inside the disc
(nucleus) may be forced out through the tears or cracks in the capsule, which
causes the disc to bulge, break open (rupture), or break into fragments.
These changes are more likely to occur in people who
smoke cigarettes and those who do heavy physical work (such as repeated heavy
lifting). People who are
obese are also more likely to have symptoms of
degenerative disc disease.
A sudden (acute) injury leading to a
herniated disc (such as a fall) may also begin the degeneration process.
As the space between the vertebrae gets smaller, there is less padding
between them, and the spine becomes less stable. The body reacts to this by
constructing bony growths called bone spurs (osteophytes). Bone spurs can put
pressure on the
spinal nerve roots or spinal cord, resulting in pain
and affecting nerve function.
What are the symptoms?
Degenerative disc disease
may result in back or neck pain, but this varies from person to person. Many
people have no pain, while others with the same amount of disc damage have
severe pain that limits their activities. Where the pain occurs depends on the
location of the affected disc. An affected disc in the neck area may result in
neck or arm pain, while an affected disc in the lower back may result in pain
in the back, buttock, or leg. The pain often gets worse with movements such as
bending over, reaching up, or twisting.