Posterior dislocations of the humerus account for less than 5 % of shoulder dislocations and are usually due to direct force. Classically, the causes are seizure or electric shock. The axillary view is the best view to demonstrate this type of dislocation.
AP radiograph of the right shoulder. A cursory examination reveals no obvious dislocation.
Axillary radiograph. Notice the anterior coracoid with the posteriorly dislocated humeral head relative to the glenoid.
