Nomenclature and Classification of Lumbar Disc Pathology

(Figure 14)

Relationship of typical posterior disc herniations with the posterior longitudinal ligament.  A,  Midline sagittal section: unless very large, a posterior midline herniation usually remains entrapped underneath the deep layer of the PLL and sometimes a few intact outer anulus fibers joining with the PLL to form a “ capsule.” The deep layer of the PLL (arrow) also attaches to the posterior aspect of the vertebral body so that no potential space is present underneath. B,  Sagittal para-central section:  the PLL extends laterally at the disc level (arrowhead) but, above and below the disc, an anterior epidural space (as), where disc fragments are frequently entrapped, is present between the lateral membranes (peridural membrane) and the posterior aspect of the vertebral bodies.  (Adapted from Milette PC. Classification, diagnostic imaging and imaging characterization of a lumbar herniated disc.  Radiol Clin North Am 2000; 38:1267-1292)

Copyright © 2001 Lippincott, Williams & Wilkins
Presented by American Society of Neuroradiology, American Society of Spine Radiology
and North American Spine Society