The spine is made up of a series of individual bones called vertebrae that are stacked to form the spinal column. Between the vertebrae are flat, round, rubbery cushions known as intervertebral discs, which act as shock absorbers and keep the spine flexible. Each disc has a soft, gel-like center, called the nucleus pulposus, surrounded by a tough, fibrous outer layer called the annulus.
When these intervertebral discs deteriorate with age, they may lose fluid and become dried out. As this happens, these cushioning discs become compressed. This may lead to a breakdown of the tough outer annulus ring. In turn, this lets the nucleus pulposus to bulge out. This is called a bulging disc (or disc protrusion).
If the bulging disc continues to break down or stress the spine, the situation can worsen, and the inner nucleus pulposus may rupture out from the annulus. This is known as a or herniated, or ruptured, disc. The fragments of disc material can then press on the nerve roots located just behind the disk space. This condition can cause pain, weakness, numbness, or changes in sensation.
Symptoms of a Bulging Disc
Symptoms of a bulging disc are usually progressive and gradual. It can cause pain in the buttocks, legs, or back. It can also affect your ability to walk.
Bulging discs generally occur with multiple discs at the same time. It can also cause other disc degeneration-related issues, like lumbar stenosis.