Magnetic resonance imaging in glenohumeral instability

Area of Science:

• Orthopedics
• Radiology
• Sports Medicine

Background:

• The glenohumeral joint is highly susceptible to dislocation, with anterior instability being the most prevalent form.
• Accurate diagnosis of glenohumeral instability is crucial for effective pre-operative planning, particularly before arthroscopic surgery.

Purpose of the Study:

• To review the essential role of magnetic resonance (MR) imaging and MR arthrography in diagnosing glenohumeral instability.
• To detail the MR imaging and arthrographic techniques used for evaluating shoulder instability.
• To describe MR findings associated with various types of glenohumeral instability and common pitfalls.

Main Methods:

• Review of relevant anatomical structures of the glenohumeral joint.
• Description of magnetic resonance (MR) imaging techniques.
• Description of MR arthrography techniques.
• Analysis of MR imaging findings for anterior, posterior, and multidirectional instability.
• Identification of common imaging pitfalls.

Main Results:

• Anterior instability is linked to Bankart lesions and injuries of the anterior band of the inferior glenohumeral ligament.
• Posterior instability involves reverse Bankart and reverse Hill-Sachs lesions.
• Multidirectional instability may present with osseous changes like increased chondrolabral retroversion rather than labral pathology.

Conclusions:

• Magnetic resonance (MR) imaging and MR arthrography are indispensable for evaluating glenohumeral instability.
• Understanding specific MR findings for each instability type aids in accurate diagnosis and surgical planning.
• Awareness of potential imaging pitfalls is essential for reliable interpretation.