In its most basic form, degenerative disc disease (also known as DDD) is the pain, weakness or potential numbness that stems from a degenerated disc in the spine. A diagnosis of degenerative disc disease may be alarming at first as it sounds like a progressive, degenerative disease. However, this isn’t necessarily the case because degenerative disc disease is, in fact, not really a disease, nor is it strictly degenerative because degenerative changes in the spine are natural and common to the general population. In fact, it actually describes normal changes in the spinal discs.
Every person undergoes disc degeneration as they age. A healthy disc will contain lots of water in its center, medically known as the nucleus pulposus, which separate interlocking bones and provide cushioning, shock absorption and mobility to the spine. However, as your spine is strained over time, the discs will begin to lose water as the annulus, or the rigid outer shell of a disc, weakens.
This makes the discs less flexible and results in the gradual collapse of the disc and the narrowing of the gap in the spinal column. As the space between the vertebrae gets smaller, extra pressure can be placed on the rigid discs causing tiny cracks or tears to appear on the annulus. If severe enough, the pressure on the disc can force the jellylike fluid within the disc out through the tears, causing a herniated disc.
As the two vertebrae above and below the affected disc begin to collapse upon each other, the facet joints at the back of the spine are forced to shift which can affect their function.
Additionally, as the space between vertebrae becomes smaller and smaller, the body reacts by creating bone spurs in order to stop excess motion. This can cause pain and affect nerve function if the bone spurs start to grow into the spinal canal and put pressure on the spinal cord and surrounding nerve roots.