Annular fissure

3 things to know first

1. It describes the disc's outer ring. An annular fissure is not a fracture of a spinal bone.
2. It can be present without pain. A scan finding must be matched with symptoms and examination.
3. It is different from a herniation. A disc can have a fissure without its inner material pushing out.

What it is

Each spinal disc has a tougher outer layer called the annulus and a softer centre. An annular fissure is a separation among fibres in that outer layer. Some reports call it an “annular tear,” although the word “tear” does not necessarily mean a recent injury. A bright spot in the outer disc on certain MRI sequences may be called a high-intensity zone (HIZ).

Why it appears on your report

MRI can show signal changes in the annulus and other disc findings at the same spinal level. The radiologist may describe a fissure alongside disc bulging, degeneration, or narrowing near a nerve. CT may show some related changes but is less suited to the soft-tissue detail of a fissure.

How serious is it

The significance varies. A fissure can be an incidental finding; in another person, it may be considered together with matching back pain. Its size or MRI brightness alone cannot establish that it is the pain source or that an operation is needed.

When to seek care urgently

Seek urgent assessment for new bladder or bowel problems, numbness around the groin, rapidly worsening weakness, or severe back pain with fever or major injury.

What usually happens next

1. Identify the disc level and any associated nerve or canal finding.
2. Discuss whether symptoms and examination match that level.
3. Follow a clinician's advice on activity, rehabilitation, and whether further review is needed.

A simple analogy

A disc resembles a cushion with a fibrous outer cover. A fissure is a small separation in the cover; it does not tell you by itself how the cushion is functioning.

Further reading

• RadiologyInfo — Discography and the Annulus
• RadiologyInfo — Spine MRI