Diffuse marrow edema with end plate erosions and mild compression of inferior end plate of L5/S1. The intervertebral disc space is grossly reduced with secondary loss of internal architecture and signal abnormality.
Peripherally enhancing anterior epidural space collection seen
L4/L5 level also shows marrow edema with anterior vertebral body erosions. The intervertebral disc shows signal abnormality.
Diffuse marrow edema also seen involving the S2 vertebral body.
Large volume collection with enhancing walls noted to involve the entire left ilio-psoas major muscle. This collection is seen to breach its ipsilateral quadratus lumborum and anterior / middle lumbo-dorsal fascia to extend into the subcutaneous plane. Collection also enters into the prevertebral space from L5 to S2 level.
The left transverse abdominus and internal / external oblique muscle shows intrasubstance hyperintensities, in keeping with edema.