Spinal disc herniation condition affecting the spine in which a tear in the outer, fibrous ring of an intervertebral disc allows the soft, central portion to bulge out beyond the damaged outer rings. Disc herniation is usually due to:
- age-related degeneration of the outer ring, known as the anulus fibrosus,
- trauma lifting injuries or straining .
Tears are almost always postero-lateral (on the back of the sides) owing to the presence of the posterior longitudinal ligament in the spinal canal. This tear in the disc ring may result in the release of chemicals causing inflammation, which may directly cause severe pain even in the absence of nerve root compression.
A variety of terms are used to describe the degree and type of disc herniation including:
- Annular tear