Extruded Disc

56-year-old male with abrupt onset back pain radiating to the left lower extremity. There is a well circumscribed ovoid T1 hypointense to skeletal muscle, STIR and T2 hyperintense, peripherally enhancing lesion arising at the L2-L3 disc level with extension inferiorly over the L3 vertebral body. The lesion extends to the right paracentral and subarticular zones on the axial T2 weighted images. It is continuous with the disc space at the L2-L3 level. Findings are most compatible with a disc extrusion. Disc extrusions are characterized by a longitudinal axis greater than the neck of the disc at the vertebral margin. Extrusions are secondary to degeneration of the annulus fibrosis allowing herniation of the nucleus pulposus. Extrusion can be in any axial direction and the disc material can migrate either superiorly or inferiorly.