Intervertebral disc

An intervertebral disc is located between each vertebra in the spinal column and provides shock absorption for the spine. These elastic, tough discs also prevent the bony vertebrae from rubbing against each other when the body moves.

Intervertebral discs play a crucial role in overall spine health. However, because the discs are integral to a healthy spine, they are also susceptible to damage throughout the years. Understanding the purpose of an intervertebral disc will help you make daily choices to protect your overall spine health.

Composition of an intervertebral disc

Intervertebral discs possess a unique shock-absorbing quality because they are comprised of a gel-like nucleus (nucleus pulposus) and a tough, elastic outer layer (annulus fibrosis).

The outer layer of the disc is a tough material made of collagen fibers that anchor the disc to each vertebra. The nucleus pulposus inside is a jellylike substance with a much higher concentration of water, and it is protected and contained by the annulus fibrosus. These two components work together to allow the disc to absorb the shock of daily movements and pressure on the spine while still maintaining the proper structure and space between the vertebrae.

Damage to an intervertebral disc

Over time, a disc may undergo consistent pressure from the surrounding vertebrae and may slowly begin to deteriorate. When this happens, certain degenerative conditions may develop, such as a herniated disc or bulging disc.

A bulging disc differs from a herniated disc in that the disc itself does not split open; it simply stretches. A herniated disc or ruptured disc, on the other hand, is an intervertebral disc in which the annulus fibrosus has split or become torn, causing the interior fluid to leak out.

In the instance of a bulging disc, the intervertebral disc flattens under pressure and extends out beyond its normal place in the spinal column. This condition can result from a number of causes, including injury, age or other disc damage.

Sometimes, a bulging disc does not cause symptoms because it is not pressing on the nerve roots in the spinal canal. However, when the bulge extends far enough, it can press on the nerve roots, causing symptoms such as radiating pain in the neck, back, legs or arms or numbness in the extremities.

Lumbar intervertebral discs

Ninety percent of damaged intervertebral discs occur in the lumbar spine (lower). This is because the lumbar spine undergoes the most pressure from supporting the weight and movements of the body.

A lumbar bulging disc primarily occurs in one of two locations: at the L4 to L5 segments of the spinal column, or at lumbar vertebra five (L5) and sacral vertebra one (S1). Another lower back problem, known as sciatica, occurs when a bulging disc is pressing on the sciatic nerve in the lower back. For more information about intervertebral discs and the spine conditions that can affect them, contact us today. Laser Spine Institute offers many minimally invasive spine procedures to help treat damaged discs with a lower risk than traditional open neck or back surgery. Call us today for a no-cost MRI review* to determine if you are a candidate for our procedures.

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