Mechanisms of shoulder trauma: Current concepts

Figure 3 Posterior shoulder dislocation. A: In the frontal view the distance of the medial cortical margin of the humeral head and the anterior glenoid rim was more than 6 mm, constituting a positive rim sign; B: A slightly oblique view with appreciable through sign (orange arrows). The humeral head was in internal rotation and hooked on the posterior rim of the glenoid fossa; C: The post reduction anteroposterior radiograph showed normal alignment and congruity of the glenohumeral articulation.