Causes / typical injury mechanism: A Bankart lesion is a shoulder injury that consists of damage to the anteroinferior labrum and inferior glenohumeral ligament. This injury is almost always associated with anterior dislocation of the humeral head in relation to the glenoid, and it predisposes the patient to future shoulder instability.
Anterior dislocation of the shoulder is often caused by sports-related trauma, such as hyperabduction and external rotation of the shoulder.
Classic history and presentation: In the case of a Bankart lesion, damage to the anteroinferior labrum and inferior glenohumeral ligament leave the shoulder unstable. Patients will complain of pain and describe the instability as a feeling of impending shoulder dislocation. The damaged shoulder will be most vulnerable to recurrent dislocation when the arm is abducted and externally rotated.
Prevalence: The lifetime incidence of anterior dislocation of the shoulder is approximately 2%.
- Age – More common among young patients (< 30 years old).
- Sex / gender – More common among men.
Risk factors:
- Male sex
- Age younger than 22-25 years
- Young age at the time of first shoulder dislocation
- Participation in contact sports
Pathophysiology: There is typically a traumatic injury in which the arm and shoulder are placed in the abducted and externally rotated position, resulting in the humeral head displacing from the glenoid. Anterior displacement is the most common direction for dislocation. Typically, the anterior, inferior glenoid labrum and the anterior, inferior glenohumeral ligament are torn after anterior shoulder dislocations. The anterior joint capsule stretches out, and there can be some redundancy in the capsular location with increased capsular volume. In patients older than 40 years, shoulder instability is also associated with
rotator cuff tears.