Degenerative
Disc Disease (DDD)

The most common causes and risk factors of degenerative disc disease are age, physical strain, genetics, and inadequate nutrition.

Risk Factors for Degenerative
Disc Disease

Age. Age is by far the most common risk factor for degenerative disc disease. Just like every other part of the body, our spinal discs age. An aging spinal disc loses water and structural integrity, which makes the disc more susceptible to rupture and herniation.

Genetic predisposition. Like aging, we cannot control our genetics. Degenerative disc disease is well known to run in families; thus, there must be one or more genes that predispose to degenerative disc disease. If you have relatives with degenerative disc disease, there is a reasonable chance you will, too.

Mechanical stress. Mechanical stress causes degenerative disc disease by stressing and straining the spinal discs. We know this because people in certain professions are more likely to develop degenerative disc disease than people in other professions. For example, degenerative disc disease is more common in long-haul truck drivers and carpenters than in office workers or school teachers. Interestingly, repeated stresses (carpentry) or long periods of inactivity (long-haul trucking) are both bad for spinal health.

Obesity. Excess weight puts excess strain on the spine, meaning the spinal discs have to withstand greater forces. Indeed, people who carry excess weight are at increased risk for degenerative disc disease.

Inadequate nutrition. Fortunately, most Americans get all of the calories, vitamins, and mineral they need from their diets. However, the blood vessels around the spine do not always deliver nutrient-rich blood to the places that need it. This is likely related to age but may also be related to diseases that damage small blood vessels, like diabetes.

Smoking. Smoking appears to speed up the process of disc aging, making them more prone to degenerative disc disease.

It is impossible to predict how quickly degenerative disc disease will progress. In some, the process takes more than 20 years. In others, symptoms may occur within a few years of anatomic changes. People with more risk factors are more likely to have a faster progression of degenerative disc disease, in general.

What are the Stages of
Degenerative Disc Disease

While there are no true stages of degenerative disc disease, the disease process does tend to progress in three phases: dysfunction, relative instability, and re-stabilization.

Stage 1: Dysfunction. If you could look directly at the spinal disc during this stage, you would see small tears in the outer layer of the annulus fibrosis (outer ring of the spinal disc).

Stage 2: Relative instability. The nucleus pulposus (inner disc material) starts to extend beyond the annulus fibrosis.

Stage 3: Re-stabilization. Bone spurs appear at the edges of the disc, essentially fixing the damage in place. The patient may no longer have dysfunction, but the height between the spinal bones is shorter, and the disc is more likely to rupture in the future.