Shoulder MRI — Rotator Cuff, Labrum & When to Add Arthrography

Shoulder MRI

The go-to test for the rotator cuff and labrum — with a decision built in: plain MRI, or MR arthrography for the harder labral questions.

Rotator cuff

MRI grades cuff pathology from tendinopathy through partial- to full-thickness tears, and — crucially for surgical planning — measures tear size, tendon retraction and muscle atrophy/fatty infiltration, which predict repairability.

Fluid-sensitive sequences (T2 fat-sat/PD) show the fluid tracking through a tear; the surgeon cares as much about muscle quality as about the tear itself.

Labrum & instability

Bankart lesion: antero-inferior labral tear after anterior dislocation.
SLAP tear: superior labrum, anterior-to-posterior, at the biceps anchor.
Bony lesions: Hill-Sachs and bony Bankart.

When to add MR arthrography

Injecting dilute gadolinium into the joint distends it and outlines the labrum, improving detection of labral and subtle cuff-undersurface tears — valuable in young patients with instability or suspected SLAP tears. Routine cuff assessment usually does not need it.

Reference: Zlatkin MB, Rosner J. MR imaging of the shoulder: current practice. Radiol Clin North Am reviews; Goutallier fatty-infiltration grading on MRI.

Educational summary for clinicians; protocol choice follows local practice. Not medical advice.