New left lower extremity weakness Five lumbar type vertebral bodies are presumed to be present. Vertebral body heights are within normal limits. There is grade 1 retrolisthesis of L5 on S1 and mild straightening. Alignment is otherwise within normal limits. Bone marrow signal is benign with edematous changes involving the L5 and S1 endplates related to degenerative disease. The conus medullaris is normal in position.Multilevel degenerative changes are seen, as described below:L1-L2: No significant disc disease. No spinal canal or neural foraminal stenosis. Mild facet arthropathy.L2-L3: Minimal disc bulge. No spinal canal stenosis. Minimal bilateral neural foraminal narrowing. Mild facet arthropathyL3-L4: Minimal disc bulge. No spinal canal stenosis. Mild to moderate left and mild right neural foraminal stenosis. Mild facet arthropathyL4-L5: Minimal disc bulge. Bilateral facet arthropathy. No spinal canal or right neural foraminal stenosis. Minimal left neural foraminal narrowing.L5-S1: Disc desiccation and mild retrolisthesis. Evidence of prior right-sided laminotomy. Previously seen (2012) large right-sided disc protrusion is no longer evident. There is diffuse disc bulge and facet arthropathy without significant spinal canal stenosis. There is moderate to severe right and mild left neural foraminal narrowing. There is also contact of the disc bulge with the left S1 nerve root in the left lateral recess at the L5-S1 level. Conjoined left L5 and S1 nerve roots in the thecal sac at the mid L5 level incidentally noted and a normal variant.
Multilevel degenerative changes in the lumbar spine as described above. There is no significant spinal canal stenosis at any level. Given history of left-sided symptoms, left-sided neural foraminal narrowing is relatively worse at the left L3-L4 and left L5-S1 levels. There is also effacement of the lateral recess on the left at the L5-S1 level. 