MRI
Coronal T2
Sagittal T2 fat sat
Axial T2
Huge L4/5 disc extrusion passing through the posterior longitudonal ligament with sequestration on the right side to the posterior epidural space causing the ligamentum flavum to be displaced posteriorly (arrow). Thecal sac is obliterated at this level being displaced towards the left. Note the sequestrated disc material posteriorly is slightly hyperintense to the extruded disc