Bulging Disc

A bulging disc occurs when weakness in the annulus, or wall, of the intervertebral disc becomes weakened to the point where it bulges into the spinal ligaments or nerve root of the spine.

Sometimes, the terms "herniated disc" and "bulging disc" are used interchangeably, though they describe slightly different conditions. Both terms refer to degenerative conditions of the intervertebral discs of the back where the wall of the outside of the disc, known as the "discus annulus", becomes weakened.

Sometimes, the wall of the disc becomes worn or weakened to the point that the pressures from the fluid pushing on its wall caused it to bulge outwards. When this happens, this condition is known as a bulging disc. When the disc is frayed to the point where it becomes torn, allowing its contents to be ejected outside of the disc, this condition is known as a herniated disc.



In the majority of cases, discs that have undergone degenerative changes don't herniate. Like a herniated disc, a bulging disc can also affect the adjacent nerve roots by pressing into the nerve and causing dysfunction. Bulging discs may also cause pain when the protruding annulus fibrosis (wall of the disc) presses into the ligaments. Many of these spinal ligaments are supplied with nerve fibers that react to pain signals when the ligaments are chronically stretched. When the bulging disc comes into contact with the nerve root with enough pressure to irritate the nerve root, we may feel pain or, changes in sensation, or other neurologic function to the body parts that nerve supplies. When a nerve root that branched with the sciatic nerve in the lumbar spine is irritated or compressed, we may feel a tingling or numbness in our leg or feet. If the bulging disc causes enough stress on the nerve root, we may experience more serious changes in functioning, such as difficulty pushing off with our feet. Serious neurologic changes such as these are rare. If a ligament is irritated by a disc, the firing rate of nociceptors will increase, causing pain. Nociceptors are nerves along the surface of the ligaments that send pain signals to the brain when the ligaments are strained beyond a healthy range of motion. Either of these two situations can cause neck pain or back pain and cause painful, protective muscle spasm, called secondary muscle spasm.

It is not necessarily a dooming scenario to have the condition known as a bulging disc. Do not assume that because you have a bulging disc that the problem is going to eventually result in a herniated disc, necessitating future surgery. Bulging disc rarely end up herniating, and your disc have mechanisms to heal themselves. This may be a problem that will come an go, however. If your back problem is caused by a weak annulus that has a propensity to bulge, you will most likely suffer from lower back pain and related leg pain that will come and go several times per year.

The way you walk, sit and move may affect the frequency and severity of flare-ups of this problem. for example, we know that the wall of the disc is the weakest at its back section. The combination of slouching or bending forward and weakness at the back of the wall of the disc may make the disc more vulnerable to bulging in the back of the disc.