Atrophy of paraspinal muscles

A young male with bilateral lower limb weakness.

MRI Axial T2 and STIR images : Muscles of Spinalis compartment showing atrophy with fat replacement with odema on STIR. Involvement is bilateral and asymmetrical.
Psoas muscles are spared. Whole spine pasting image shows no significant abnormality in cord or cauda equina.

Patient evaluated further with NCV, EMG and clinically diagnosed by Neurophysician as Spinal Muscular Atrophy.

It is important to look after the para spinal muscles during MRI lumbar spine for any atrophy or signal changes like odema on STIR as in this case.