uchc.edu Acromioclavicular (AC) joint injuries are more common than sternoclavicular (SC) joint injuries. There is a spectrum of AC joint traumatic injuries that ranges from a ligament sprain to a ...

The collarbone forms the sternoclavicular joint with the sternum (breastbone) at one end and the acromioclavicular ... not spread to other areas of the body. The condition has no known cause.