Glenoid labral tear

Glenoid labral tears are the injuries of the glenoid labrum and a possible cause of the shoulder pain.

Clinical presentation

Patients with labral tears may present with a wide range of symptoms (depends on the injury type), which are often non-specific:

pain or discomfort (usually a precise point of pain cannot be located)
joint weakness
joint instability
clicking

Pathology

Labral injuries can result from acute trauma (like shoulder dislocation or direct blow) or repetitive overuse.

Localization

superior labrum
- SLAP lesion
anteroinferior labrum
posteroinferior labrum:
- reverse Bankart lesion
- posterior GLAD
- POLPSA
- Kim lesion
circumferential labral lesion

Associations

Radiographic features

MRI

On conventional MR labral tears are best seen on fat-saturated fluid-sensitive sequences. On MR arthrography it is customary to combine T1, T1 FS and T2 FS sequences for further assessment. Imaging in three planes is advisable and additional orthogonal planes may be included in the protocol for a detailed assessment of the lesion.

There is ongoing debate on whether direct MR arthrography is superior to conventional MR in detecting labral tears. A 2012 meta-analysis demonstrated the accuracy of MR arthrography was marginally superior, with a sensitivity of 88% vs. 76% for conventional MR, and a specificity of 93% vs. 87%.

The biggest advantage of MR arthrography comes from the joint distension, which can help spot otherwise occult tears. However, patients with acute lesions often have joint effusion, which also distends the joint space, making the contrast administration unnecessary.

MR arthrography has excellent accuracy in differentiating between SLAP lesion and anatomic variants.

CT arthrography

CT arthrography has been reported to have 97.3% accuracy for detecting Bankart lesions and 86.3% for SLAP lesions , which makes it comparable with MR arthrography and gives the possibility to examine the patients with contraindications to an MR examination. Apart from that, CT is superior to MR in assessing bony structures, so this modality is helpful in detecting co-existing small glenoid rim fractures.