My friend called me last night and said "I think I dislocated my shoulder!" When he told me that he had a large bump on his shoulder, I knew that it was probably not a dislocation but a shoulder separation, where the joint between the shoulder blade and collarbone is disrupted. This causes a large bump where the collarbone sticks up. Here's a picture of his shoulder.
Shoulder separations usually occur from falling directly onto the shoulder. Shoulder separations are also called AC separations. "AC" stands for acromioclavicular, which is the joint between the collarbone and shoulder blade. Some shoulder separations are minor, and do not require surgery. Others are more significant, and need surgery to reconstruct the ligaments holding the collarbone. Here's a picture of the x-ray. Can you see the end of the collarbone sticking up?
|Picture of a bad shoulder separation|
If there is only a small bump and the collarbone is not too far from its normal position, the ligaments in a shoulder separation will heal just fine on their own without surgery. It is important to understand that the bump will be permanent, but there will be no loss of strength. In the case where there is a large bump and the collarbone is way out place (as with my friend here), then surgery is necessary to repair the torn ligaments. Here is a video showing repair of a shoulder separation or AC separation.
If you think you might have a shoulder separation, getting an x-ray will confirm the position of the bones. A shoulder surgeon should be able to help you understand your options and whether or not you need surgery.