The spine consists of 24 individual vertebrae stacked on top of each other. Between each set of vertebrae are flexible cushions called “discs.” The discs have two basic components:
- The inner disc, or “nucleus,” is like a ball of jelly and about the size of a marble.
- The outer part of the disc, called the “Annulus,” holds the jelly in place. It is wrapped around the inner nucleus – much like wrapping a ribbon around your finger.
“Lumbar disc lesions” start when the outer fibers of the disc are strained or frayed, which damages the disc. If enough fibers become frayed, this can create a weakness that causes the outer fibers to “bulge” or “protrude” when the disc is compressed - like a weak spot on an inner tube. If more fibers are damaged, the nucleus of the disc may “herniate” outward.
Since the spinal cord and nerve roots are located directly behind the disc, bulges accompanied by inflammation will likely create lower back pain that radiates into the buttock or the entire lower extremity – a condition is called “sciatica.” If the disc bulge is significant enough to compress the nerve, there may also be weakness and a loss of reflexes. We ask our patients to let us know if they notice progressive weakness or numbness, any numbness around their groin, any loss of bowel/bladder control or fever. Most lumbar disc problems occur at either L5 or L4 - the two lowest discs. Surprisingly, disc bulges without any symptoms are present in about one third of the adult population. Another third of adults, primarily men, will experience pain from a lumbar disc at some point in their lifetime.
Disc bulges and sciatica are most common between the ages of 40 and 60, and are uncommon in children. Smokers and people who are generally inactive have a higher risk of lumbar disc problems, while certain occupations may place you at greater risk, especially if you spend extended periods of sitting or driving. People who are tall or overweight also have increased risk of disc problems. Research has shown that disc bulges and sciatica may be successfully managed with conservative care like the type we provide.