Wk 9, Case 1 - Review

Patient History
37 y.o. male presents to the ED with states back pain. States seeing orthopedic surgeon. States had 2nd steroid injection and taking tramadol and steroids and muscle relaxants. Last MRI shows herniated disc. States tingling left leg/numbness for 1 week. Denies weakness.

Findings
At L5-S1, there is a posterior disc extrusion which arises from the posterior central aspect of the intervertebral disc where it contacts the traversing right S1 nerve root, then extends posterolaterally into the left ventral lateral epidural space, effacing the left subarticular recess, with posterior displacement and compression of the traversing left S1 nerve root. Thecal sac deformity is also present with the disc herniation contacting the traversing left S2 nerve root, as well as moderately narrowing the thecal sac. The T2 hypointense disc extrusion measures approximately 1.3 x 1.8 x 0.8 cm (CC, transverse, AP). There is subtle postcontrast enhancement of the left S1 and S2 nerve roots at L5-S1, likely reactive. There is narrowing of the intervertebral disc space, mild degenerative endplate and facet changes, and mild narrowing of the bilateral neural foramina at L5-S1.

At the remaining levels, the lumbar spinal canal and neural foramina are widely patent. There is normal vertebral alignment and morphology. No suspicious marrow signal abnormality. Small intraosseous hemangioma noted within the right L1 pedicle. The conus medullaris terminates at the level of the mid L2 vertebral body. The conus medullaris and the cauda equina nerve roots demonstrate normal signal and morphology. No evidence of abnormal enhancement seen within the cauda equina. There is mild asymmetry of the nerve roots, with the right-sided roots appearing somewhat clustered in the right lateral aspect of the thecal sac, but this could be related to a mild curvature of the spine. The visualized abdominal pelvic and paraspinal soft tissues are normal in appearance.

Impressions
Evidence of a central and left central L5-S1 posterior disc extrusion which posteriorly displaces and compresses the left S1 nerve root, and, to a lesser extent, abuts the intrathecal segment of the left S2 nerve root and right S1 nerve root, as detailed above.

Findings
Conus medullaris terminates at the high L2 level. The cauda equina nerve roots layer dependently within the thecal sac without evidence of abnormal clumping or enhancement.Diffuse straightening of the lumbar lordosis. No significant vertebral body height loss is appreciated.

There are active endplate changes at the L5-S1 level with associated endplate edema and enhancement. No suspicious marrow signal abnormality is identified with mild diffuse low T1 signal throughout the marrow. Postoperative changes are present with left hemilaminectomy defect at the L5-S1 level. There is contrast enhancing tissue extending from the midline to the left side and along the left side of the thecal sac which encases the left S1 nerve root as it leaves the thecal sac and extends to the lateral recess. However there is nonenhancing tissue which is seen in the midline and extending to the right side abutting on and slightly displacing the right S1 nerve root. There is enhancement of the posterior paraspinal soft tissues at the L5-S1 level with associated susceptibility artifact, postsurgical in etiology.

No fluid collection identified. Prevertebral soft tissues are unremarkable.

Impressions
1. Postsurgical changes from discectomy with left hemilaminectomy at L5-S1 with interval resection/resorption of the left central disc extrusion. There is granulation tissue encasing the left S1 nerve root but residual central to right-sided disc herniation abutting on and slightly displacing the right S1 nerve root.

2. Otherwise widely patent spinal canal without significant neural foraminal narrowing.

3. Active endplate changes at L5-S1.