Disc Injuries

Many people develop a herniated or bulging disc in their spine. Injury, aging, and poor lifestyle choices are common causes of a disc problem. While a mild degree of a “bulge” may be considered normal, there are a number of different types of disc injuries that are not normal and create a great deal of pain. In severe cases, muscle atrophy, pain and numbness, can be present. When these problems exist, symptoms will show up in the lower back/legs, or arm and hand. Below, several common questions about disc problems are answered and discussed.

Do discs slip?
In lay terms, a slipped disc can mean a ruptured disc or herniated disc. Although the term slipped disc is used, discs do not actually slip. Each intervertebral disc is sandwiched between two vertebrae supported by a system of very strong ligaments that help hold the spinal package together.

What is the difference between a bulging and herniated disc?
Disc disorders are contained or non-contained. A bulging disc is an example of a contained disc disorder. A bulging disc has not broken open; the nucleus pulposus (the center section) remains contained within the anulus fibrosus (the outer layer). A bulging disc could be compared to a volcano prior to eruption and may be a precursor to herniation. The disc may protrude into the spinal canal without breaking open. The gel-like interior (nucleus pulposus) does not leak out. The disc remains intact except a small bubble pops out attached to the disc. A very simple example is a jelly doughnut. If you step on the doughnut with a lite amount of force, the jelly causes the dough to push, or “bulge” out; yet, the jelly does not leak outside the dough.

A non-contained disc is one that has either partially or completely broken open; a herniated or ruptured disc. To illustrate imagine a tube (anulus fibrosus) of toothpaste (nucleus pulposus) placed under pressure. The pressure causes the toothpaste within the tube to move wherever it can. If any part of the tube is weak toothpaste may leak out. When a disc herniates the contents may spread out to the spinal cord and nerves. The disc material has very little space to go. Usually, the disc material enters into the area occupied by the spinal canal and nerve roots. When this occurs, a number of problems will be present, starting with moderate to severe pain. Using the example of the jelly doughnut again, in this case, when stepping on the doughnut, the jelly actually breaks through the outer dough and leaks out.

Why might a herniated disc cause pain?
When the disc bulges or herniates, material from the disc puts pressure onto the nerve root or spinal cord. This pressure, onto the nerve, is what causes the pain in either the arms or legs. To complicate matters, sometimes fragments from the anulus (tire-like outer disc wall) break away from the parent disc and drift into the spinal canal. These free fragments may travel into the spinal canal. This can be a more serious condition, such as Stenosis. Depending on the type of injury and the condition of the discs, more than one disc may herniate, rupture, or bulge. Sometimes injury causes a combination of disc disorders. In and ideal situation, the problem may resolve in the first 60-90 days after the injury. However, when the problem persists over 90 days, the chance of it resolving on its own is slim.

Degenerative Disc

If an individual undergoes a number of injuries, or has abnormal wear and tear on a disc, it is possible to have degeneration. Degeneration of a disc is when the disc size and material, get thin and start to break down. When this occurs, the space between the two involved vertebrae gets smaller, closing down the foramen(hole) where the nerve root exits the spinal cord. This condition can cause a nerve to have pressure on it and create pain.  Additionally, there tends to be changes to the bone that occur in these cases. These changes come in the form of bone spurs or osteophytes, which create their own set of problems.  Some think that degeneration is normal with age, and to a degree this is true. However, when an individual has degeneration at one level or disc, and the rest are healthy, then this is not normal. Generally this is caused from an injury, or series of injuries, in which permanent damage was done, or proper treatment was not done after the injury.