Anatomy

Anatomy of Herniated Disc

illustration of the anatomy of a herniated disc

In order to understand your symptoms and treatment options, it helps to begin with an understanding of the anatomy of your low back. This includes becoming familiar with the various parts that make up the lumbar spine and how these parts work together.

Learn more about the anatomy of the lumbar spine.

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.