Degenerative Disc Disease
Degenerative disc disease (DDD) is typically associated with aging. As you age, your discs, like other joints in the body, can degenerate (break down) and become problematic: That’s a natural part of growing older as your body deals with years of strain, overuse, and maybe even misuse. However, DDD can occur in people as young as 20, so sadly, youth doesn’t always protect you from this disc-related spinal condition. In fact, some patients may inherit a prematurely aging spine.
Degenerative disc disease involves the intervertebral discs. Those are the pillow-like cushions between your vertebrae in your spine. They help your back carry weight and allow complex motions of the spine while maintaining stability. As you age, the discs can lose flexibility, elasticity, and shock absorbing characteristics. They also become thinner as they dehydrate. When all that happens, the discs change from a supple state that allows fluid movement to a stiff and rigid state that restricts your movement and causes pain.
If you have chronic back or neck pain, you may have degenerative disc disease. It commonly occurs in your low back (lumbar spine) or neck (cervical spine). Developing degenerative disc disease is a gradual process. As you can see in the illustration, there are even many stages and states your discs can go through as part of DDD. They can bulge, herniate, or thin. Because of disc changes, your vertebrae can be affected. You can see this in the illustration, too. For example, bone spurs (osteophytes) can form as your spine tries to adjust to the intervertebral disc changes.
Degenerative disc disease (DDD) can affect many parts of your spine. To understand how, you first need a basic understanding of what makes up your spine.
First of all, you have vertebrae, labeled in the image below as the “vertebral body.” In your backbone, or vertebral column, you have 33 vertebrae.
Parts of the Spine
Your spine is divided into regions:
Neck (cervical spine)
Mid-back (thoracic spine)
Low back (lumbar spine)
At the lower end of your spine, you also have the sacrum and the coccyx, which is commonly called your tailbone.
Degenerative disc disease is most likely to occur in your cervical spine or your lumbar spine.
In between your vertebrae, you have intervertebral discs (also labeled on the above image). These act like pads or shock absorbers for your spine as it moves. Each disc is made up of a tire-like outer band called the annulus fibrosus and a gel-like inner substance called the nucleus pulposus. Degenerative disc disease changes the discs and makes them less able to cushion your movements (as discussed above). With DDD, your intervertebral discs also become more prone to problems; they may bulge or herniate.
Together, the vertebrae and the discs provide a protective tunnel (the spinal canal) to house the spinal cord and spinal nerves. These nerves run down the center of the vertebrae and exit to various parts of the body where they help you feel and move. You can see the spinal cord running through the vertebrae in the image.
Your spine also has facet joints, which are on the posterior side (back) of your vertebrae. These joints (like all joints in your body) help facilitate movement and are very important to your flexibility.
Your spinal joints are covered by cartilage, which protects your bones as you move. Without cartilage, your bones would rub together—very painful. Unfortunately, your cartilage can be affected by general wear and tear on your spine, and it can wear away. That’s when bone spurs (osteophytes) can form as your body attempts to repair itself.
Muscles, Ligaments, Tendons, and Blood Vessels
Your back also has muscles, ligaments, tendons, and blood vessels. Muscles are strands of tissues that power your movement. Ligaments are the strong, flexible bands of fibrous tissue that link the bones together, and tendons connect muscles to bones. Blood vessels provide nourishment. These parts all work together to help you move.