Shoulder Labral Tear MRI Signs: SLAP, Bankart, and Instability Review

Your report says “abnormal labral signal”: tear or not?

How radiologists phrase it

• “Abnormal signal in the posterior inferior labrum”
• “Increased signal in the superior labrum, sublabral recess versus SLAP tear”
• “Linear signal undercutting the anterior labrum”
• “Sublabral foramen, a normal variant”

Signal, variant or tear

• A sublabral recess is a normal groove under the superior labrum. In a cadaver study it was present in 73% of shoulders and looked much like a SLAP tear.
• A sublabral foramen and a Buford complex are normal variants at the front and top of the labrum that can look detached or missing on MRI.
• Contrast or fluid entering the labrum, an irregular edge or a displaced labral fragment favor a tear, which is then named by location: SLAP at the top, Bankart at the front-bottom, or posterior.

Does the wording change treatment?

Signal alone rarely settles the question; your doctor combines it with any instability, dislocation history and examination. When a standard MRI is uncertain, an MR arthrogram can show the labrum more clearly: in a meta-analysis it detected labral lesions slightly more accurately than MRI.

What to ask at your follow-up

• Is this signal more likely a tear or a normal variant, and where on the labrum is it?
• Does the location fit my symptoms or my dislocation history?
• Would an MR arthrogram or another test change the plan?

Overview

The glenoid labrum is a fibrocartilaginous ring that deepens the shoulder socket and serves as an attachment point for the glenohumeral ligaments and long head of the biceps tendon. Labral tears are classified by location and pattern: SLAP (Superior Labrum Anterior to Posterior) tears involve the superior labrum at the biceps anchor, while Bankart lesions involve the anteroinferior labrum and are associated with shoulder dislocations. This page focuses on the imaging workup: where the labrum is torn, which MRI planes show it best, and whether instability-related bone injuries are also present.

For a deeper guide to superior labrum types, read the SLAP tear classification guide. For dislocation-related labral injury and bone loss, see the Bankart and Hill-Sachs MRI guide.

How MRI Separates SLAP, Bankart, and Posterior Tears

A SLAP lesion is centered at the superior labrum and biceps anchor, so coronal-oblique and axial images are reviewed for fluid undercutting the labrum, detachment of the biceps anchor, or extension into the long head of biceps tendon. These findings explain deep pain with overhead loading, throwing, or traction injuries.

A Bankart lesion sits at the anteroinferior labrum after anterior dislocation. Axial images are checked for labral avulsion, capsulolabral stripping, glenoid rim fracture, and a matching Hill-Sachs impaction injury on the humeral head. Posterior labral tears are assessed separately because they can follow posterior instability or repetitive loading rather than classic anterior dislocation.

Imaging Questions This Page Helps Answer

• Is the tear superior, anterior, posterior, or circumferential around the glenoid?
• Does the abnormal signal extend into the biceps anchor, suggesting a SLAP pattern?
• Is there a Bankart lesion, bony Bankart fragment, or glenoid bone loss after instability?
• Are associated findings present, such as a Hill-Sachs lesion, paralabral cyst, cartilage injury, or rotator cuff tear?

AI Search Quick Answers

• Can MRI show a shoulder labral tear? MRI can show many labral tears, especially when fluid or contrast separates the labrum from the glenoid. MR arthrogram may be better for subtle SLAP, Bankart, or posterior tears.
• Can X-ray diagnose a labral tear? X-ray does not directly show the labrum, but it can show related bone findings such as glenoid rim fracture, Hill-Sachs injury, arthritis, or dislocation alignment.
• When is CT better than MRI? CT is better for glenoid bone loss, bony Bankart fragment size, and fracture detail after instability. MRI is usually better for the labrum, capsule, biceps anchor, cartilage, and rotator cuff.
• What can AI not diagnose? AI cannot confirm shoulder instability, choose surgery, or replace a clinician who compares imaging with symptoms and physical exam.

Review images in the free shoulder MRI viewer or free shoulder CT viewer, then compare related pages for shoulder impingement and clavicle fracture.