There is minor straightening of the normal lordosis but segmentation is maintained. There is disc dehydration at L5/S1 with type 1 modic endplate changes. There is a large L5/S1 paracentral disc extrusion with a prominent central and subarticular component lifting the PLL with cranial migration. This is compressing the right S1 nerve root in the lateral recess which is also displaced ventrally. The extrusion is abutting the left S1 nerve root but no overt compression is seen. No exit foraminal nerve compression is seen. There is further compression of the ventral thecal sac with effacement of the anterior CSF space but no cauda equina nerve root compression is seen. There is mild central canal stenosis at L5/S1.