Unlike the more commonly recognized anterior shoulder instability, posterior instability is often underdiagnosed and can result from various factors, including labral tears and glenoid bone loss.

The glenoid labrum contributes to the stability of the shoulder by increasing the concavity in which the humeral head glides. Anterior, posterior, and multidirectional shoulder instability have ...

The posterior capsule is then stretched by pushing the arm into cross-arm horizontal adduction. With a posteriorly-directed force on the humerus, the shoulder is externally rotated and then ...