Which injury is commonly referred to as a shoulder separation?

• A. AC joint sprain
• B. SC joint dislocation
• C. GH dislocation
• D. ST joint sprain

Answer: (A)

Shoulder separation refers to an injury at the acromioclavicular joint, where the clavicle meets the acromion of the scapula. When a direct hit to the shoulder or a fall on the shoulder forces the bones apart, the ligaments holding the AC joint can stretch or tear. That separation of the clavicle from the acromion causes pain at the top of the shoulder, swelling, and often a noticeable bump or step-off, reflecting ligament injury rather than a dislocation of the shoulder itself.

This is distinct from other shoulder injuries. A true shoulder dislocation involves the ball-and-socket joint of the shoulder (the glenohumeral joint) and is not called a separation. An injury at the sternoclavicular joint would be a different kind of joint issue near the center of the chest, and scapulothoracic (ST) issues relate to the movement between the shoulder blade and the thorax rather than a separation of two bones at a joint. Therefore, the condition commonly called a shoulder separation is an AC joint sprain.