Every once in a while out of no where, my clavicle feels like its been disconnected from my shoulder and i can't lift my arm. What is this and why?
There are several possible causes of your shoulder problem. It can be a rotator cuff problem, or if you are under 20, then it can be some instabiility of your shoulder. If you fell directly on your shoulder, it can be a shoulder separation.
You should see an orthopedist if the problem continues.