The Inferior Stability Provided by the Glenohumeral Capsule Increases With External Rotation in the Abducted Glenohumeral Joint

The shoulder is the most frequently dislocated major joint in the body, and the glenohumeral capsule is the primary stabilizer to the joint in positions of dislocation. Although the majority of dislocations occur in the anterior direction, multidirectional instability is common and usually occurs in the anterior and inferior directions. Clinicians have difficulty differentiating between multidirectional and unidirectional instability, and greater than 38% of post-operative recurrences may be due to misdiagnosis of the type of instability [1].