The "Crumble Disc Sign": A Specific MRI Sign of Intradural Lumbar Disc Herniation, Allowing a Preoperative Diagnosis.

Intradural disc herniation (IDH) is very rare. Most diagnoses were surgical but with the improvements in magnetic resonance imaging (MRI) it has become possible to preoperatively diagnose intradural migration of disc in some cases. We report a case with very specific imaging features in MRI, well correlated with the surgical findings.