It’s common to hear the terms “ruptured disc” and “slipped disc.” People often assume that everyone who has back pain has a ruptured disc. However, a true herniated nucleus pulposus (the medical name for this problem) is not very common.
The intervertebral discs are the shock-absorbing cushions between each vertebra of your spine. There is one disc between each vertebra. Each disc has a strong outer ring of fibers, called the annulus, and a soft, jelly-like center, called the nucleus pulposus.
The annulus is the disc’s outer layer and the strongest area of the disc. The annulus is actually a strong ligament that helps connect each vertebra together. The nucleus in the center of the disc serves as the main shock absorber.
A herniated disc occurs when the intervertebral disc’s outer fibers (the annulus) are damaged and the soft inner material of the nucleus pulposus ruptures out of its normal space. If the annulus tears near the spinal canal, the nucleus pulposus material can push into the spinal canal.
A true herniated nucleus pulposus is most common in young and middle-aged adults. It rarely occurs in children. Degenerative changes in the spine that occur with aging actually make it less likely to develop a true herniated disc. This is because the nucleus in the middle of the disc dries out, making it less likely to squeeze out of the disc.
Discs can rupture suddenly because of too much pressure all at once. For example, falling from a ladder and landing in a sitting position can cause a great amount of force through the spine. If the force is strong enough, either a vertebra can break or a disc can rupture. Bending places high forces on the discs between each vertebra. If you bend and try to lift something that is too heavy, the force can cause a disc to rupture.
Discs can also rupture from a small amount of force, usually due to weakening of the annulus from repeated injuries that add up over time. As the annulus becomes weaker, at some point lifting or bending causes too much pressure across the disc. The weakened disc ruptures while doing something that five years earlier would not have caused a problem. This is due to the effects of aging on the spine-the most common reason for a disc herniation in the lumbar spine.
A herniated disc causes problems in two ways. First, the material that has ruptured into the spinal canal from the nucleus pulposus can cause pressure on the nerves in the spinal canal. There is also some evidence that the nucleus pulposus material causes a chemical irritation of the nerve roots. Both the pressure on the nerve root and the chemical irritation can lead to problems with how the nerve root functions. The combination of the two can cause pain, weakness, and numbness in the area of the body to which the nerve supplies sensation.
The symptoms of a true herniated disc may not include back pain at all. The symptoms come from pressure on, and irritation of, the nerves. But many people do have back pain because they have other problems in their back when the disc ruptures. The symptoms of a herniated disc usually include:
- pain that travels into one or both legs
- numbness or tingling in areas of one or both legs
- muscle weakness in certain muscles of one or both legs
- loss of the reflexes in one or both legs
Where these symptoms occur depends on which nerve(s) has been affected in the lumbar spine. Therefore, the location of the symptoms helps determine your diagnosis. Knowing where the pain is perceived gives your doctor a better idea of which disc has probably ruptured.
Diagnosing a herniated nucleus pulposus begins with a complete history of the problem and a physical exam. Your doctor will want to make sure that you are aware when you have to urinate or have a bowel movement. If there is a problem, it could indicate that a herniated disc in the lumbar spine is pushing against the spinal cord. Diagnostic testing is often used. These can include X-rays, MRI, CT Scan, and Discogram.
The treatment of a herniated disc depends on the symptoms. If the symptoms are getting better, your doctor may suggest watching and waiting to see if they go away. If they are getting steadily worse, your doctor may be more likely to suggest surgery. Many people, who initially have problems due to a herniated disc, find their symptoms completely resolve over several weeks or months.
Treatment can include observation, pain medication, rest, physical therapy, epidural steroid injections (ESI). Surgical treatment for a herniated disc depends on several factors and can include; laminectomy and discectomy, and minimally invasive discectomy.