Extruded lumbar disc

Case contributed by Dr Ian Bickle


Acute on chronic pain radiating to the right thigh. MRI 2 years prior. No significant findings. Nerve root impingement?

Patient Data

Age: 55 years
Gender: Male

Extruded right L1-L2 paracentral intervertebral disc with caudal descent into the infrapedicular zone.

The disc effaces the right lateral recess narrowing the central canal and impinging on the right L2 descending nerve root.  The L1 nerve exits without impingement.

L1-L2 Schmorl's node.

Calcification of the T11-T12 disc.

The remaining levels are unremarkable.

Case Discussion

A relatively small proportion of intervertebral disc herniations are extrusions. Key aspects are:

  1. The disc herniation has a wider dome than neck.  Hence the name given to this appearance on sagittal images, the toothpaste sign.The bulge of toothpaste at the tip being wider than the neck where it exits the tube.
  2. The extension of the disc cranially (suprapedicular) or caudally (infrapedicular).
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Case information

rID: 59610
Published: 18th Apr 2018
Last edited: 16th Jul 2018
Tag: ripas2
Inclusion in quiz mode: Included

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