Shoulder: labrum and bicipital tendon.

Area of Science:

• Orthopedic Surgery
• Radiology
• Sports Medicine

Background:

• Shoulder instability results from acute trauma, generalized laxity, or repetitive microtrauma, common in throwing athletes.
• The anterior inferior labral tear with capsuloperiosteal stripping (Bankart lesion) is the most frequent labral injury.
• Variants like ALPSA and SLAP lesions, along with long head of biceps tendon pathology, are increasingly recognized.

Purpose of the Study:

• To review the spectrum of shoulder instability lesions.
• To highlight the role of MRI and MR arthrography in diagnosing these conditions.
• To emphasize the importance of understanding shoulder anatomy and biomechanics for accurate interpretation.

Main Methods:

• Review of common shoulder instability pathologies.
• Discussion of imaging modalities, focusing on conventional MRI and MR arthrography.
• Correlation of imaging findings with anatomical structures and biomechanics.

Main Results:

• Conventional MRI and MR arthrography demonstrate good accuracy in preoperative diagnosis of shoulder instability lesions.
• Identification of various labral lesions (Bankart, ALPSA, SLAP) and biceps tendon pathologies.
• Understanding normal anatomy is key to interpreting abnormal findings.

Conclusions:

• Accurate preoperative diagnosis of shoulder instability lesions is achievable with MRI and MR arthrography.
• Knowledge of normal shoulder anatomy and biomechanics is essential for interpreting imaging findings.
• Comprehensive evaluation aids in planning appropriate surgical or non-surgical management.