Disc herniation

Dr Craig Hacking and A.Prof Frank Gaillard et al.

Disc herniation refers to the displacement of intervertebral disc material beyond the normal confines of the disc but involving less than 25% of the circumference (to distinguish it from a disc bulge). A herniation may contain nucleus pulposus, vertebral endplate cartilage, apophyseal bone/osteophyte and annulus fibrosus

Disc herniations can be divided into groups in a variety of ways. Commonly they are divided into protrusion vs extrusion: 

  • protrusion
    • base wider than herniation
    • confined to disc level
    • outer annular fibers intact
  • extrusion
    • base (a.k.a. neck) narrower than herniation 'dome'
    • may extend above or below endplates or adjacent vertebrae
    • complete annular tear with passage of nuclear material beyond disc annulus
    • disc material can then migrate away from annulus or become sequestered

Herniations can further be classified as:

  • contained
  • not contained
    • tear of outer fibers of annulus fibrosus and posterior longitudinal ligament

See also

Spine
Share article

Article information

rID: 6191
Synonyms or Alternate Spellings:
  • Herniated disk
  • Herniated disc
  • Herniation of the disk
  • Herniation of the disc
  • Disc herniations
  • Disk herniation
  • Disk herniations

Support Radiopaedia and see fewer ads

Cases and figures

  • Normal
    Figure 1: normal
    Drag here to reorder.
  • A focal disc prot...
    Figure 2: disc extrusion
    Drag here to reorder.
  • Figure 3: disc protrusion
    Drag here to reorder.
  • Figure 4: disc extrusion
    Drag here to reorder.
  • Figure 5: disc sequestration
    Drag here to reorder.
  • Figure 6: lumbar disc herniation
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.