Anatomy of a Herniated Disc

A herniated disc can occur as a result of aging, injury, or both. Due to the complex system of nerves surrounding the spinal discs, even a minor herniation can cause debilitating pain.

See What's a Herniated Disc, Pinched Nerve, Bulging Disc...?

To help you better understand how a disc herniation occurs, here is a step-by-step visual walk through of the process.

See Typical Symptoms of a Herniated Disc


Herniated Disc Video

The spinal disc sits in between two vertebrae. Each disc has two primary components:

  • The nucleus pulposus, a softer, gel-like substance in the center of the disc.
  • The annulus fibrosus, which consists of several of the disc’s outer layers

Read more: Spinal Discs

In addition to supporting the vertebrae, each spinal disc helps to facilitate movement. When this structure degenerates, disc herniations are more likely to occur.

See Spinal Anatomy and Back Pain

Weakened discs

Degeneration starts when layers of the annulus fibrosus weaken.

Herniated Disc Video

If the annulus fibrosus weakens enough, eventually the nucleus pulposus may seep out past the annulus fibrosus and affect a nearby nerve, which is when it starts to cause symptoms.

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Herniated Disc Video

Nerve pain

In the case of a lumbar herniated disc, a spinal nerve root sits just above the location where the annulus fibrosus commonly weakens. When the disc herniates, the nucleus pulposus can put direct pressure on the nerve root.

See 5 Little-Known Tips for Lumbar Herniated Disc Pain Relief

Herniated Disc Video

This pressure on the nerve root causes pain, numbness, weakness, or tingling sensations down the leg along the nerve path. This is known as sciatica pain.

Read more: What You Need to Know About Sciatica

Everyone experiences a herniated disc differently. Some individuals may have a herniated disc and experience no symptoms, while others may have severe sciatica pain from a relatively small disc herniation.

Learn more:

Diagnosing Disc Problems

Sciatica Causes

Leg Pain and Numbness: What Might These Symptoms Mean?

Post written by Daniel Perret