Acute traumatic anterior shoulder instability

Abstract

The complex relationship between increased range of motion and decreased stability subjects the shoulder to more episodes of subluxation and dislocation than other joints in the body. Traumatic anterior glenohumeral dislocation remains a common problem not only in young athletes but also for older individuals after a fall. The most common mechanism of injury remains shoulder abduction with forced external rotation. The shoulder is a complex joint composed of static and dynamic stabilizers. During an episode of shoulder abduction and forced external rotation, the humeral head places significant stress on the anterior-inferior labrum. At the time of dislocation, the humeral head experiences axial loading, external rotation, and anterior translation. The pathoanatomy of the traumatic anterior dislocation in young patients is typically the Bankart lesion (also known as the Perthes-Bankart lesion), where the anterior-inferior capsulolabral complex is forcefully pulled from the glenoid during the dislocation.