Piriformis syndrome is an uncommon cause of buttock and hip pain due to entrapment of the sciatic nerve by the piriformis muscle at the greater sciatic notch.

The coronal T1-weighted images demonstrate enlargement of the right piriformis muscle (arrow).
The corresponding axial T2-weighted image confirms enlargement of the right piriformis muscle (arrow).

A coronal inversion recovery weighted image demonstrated no abnormal signal intensity within either piriformis muscle (arrows).

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