AC Sprain & Separation

The AC joint, or acromioclavicular joint, is the junction where the clavicle, or collarbone, attaches to the shoulder blade. This joint is a small bump that can be felt over the top of the shoulder especially if there has been a previous injury. The AC joint is stabilized by ligaments that can be injured by a direct fall onto the front or top of the shoulder. This type of injury is called an AC joint sprain or separation.


The most common cause for an AC joint sprain or separation is a direct fall onto the point of the shoulder.  This injury is common in cyclists.


Pain over the AC joint is the most common symptom.  There can be loss of motion as well, more significant with more severe injuries.


Procedural options include cortisone injections to the AC joint for chronic pain resulting from AC sprain/separation.  In the acute phase, cortisone is not recommended as it can impede healing.  Regenerative-type injections (such as platelet-rich plasma (PRP)) can theoretically provide longer lasting pain relief and improved function by stimulating the body’s own natural healing response when conventional treatments have failed.