Fig. 4
From: Nerve entrapment syndromes of the upper limb: a pictorial review
20-year-old male with 6 months’ history of shoulder weakness. Axial (a) and sagittal (b) PDFS sequences show a posterior labral tear with paralabral cyst (white arrows) extending into the spinoglenoid notch. There is atrophy and mild denervation oedema in the infraspinatus muscle (b, blue arrow), sparing the supraspinatus since the site of entrapment is distal to the supraspinatus innervation