The rest of the lumbar vertebral bodies and the remaining intervertebral discs reveal normal signal intensity. The facet joints and the visualized pre and paravertebral soft tissues are unremarkable.
The conus medullaris terminates at the D12-L1 level and the thecal sac terminates at the S1 level.
The antero-posterior dimensions of the lumbar canal at the level of the intervertebral discs are as follows :
19.0 mm at L1-L2
18.0 mm at L2-L3
13.0 mm at L3-L4
9.0 mm at L4-L5
10.0 mm at L5-S1.
The images of the sacro-iliac joints reveal an ill-defined, hypointense signal on the T1 Weighted images in the marrow of the sacral and iliac bones adjacent to the right sacro-iliac joint. This lesion appears hyperintense on the STIR images. The cortical margins of the right sacro-iliac joint appear intact. Minimal fluid is noted in the right sacro-iliac joint per se.
The visualized left sacro-iliac joint appears unremarkable.
IMPRESSION :
1. A small, postero-central disc herniation at the L4-L5 level.
2. Slight anterior wedging of the D10, D12, L1 and L2 vertebral bodies with fatty marrow changes may be the sequelae of previous trauma.
3. Altered signal in the sacral and iliac bones adjacent to the right sacro-iliac joint is not specific for a single etiology. These changes may be the sequelae of previous trauma, or may represent sacro-ilitis.