I recently had arthroscopy surgery on my shoulder for an impingement. Two weeks after the surgery I began having sharp pain in the top of my shoulder, near the shoulder joint every time I moved my arm. My Ortho doctor gave me 2 cortozone shots over the next 2 weeks with no relief in pain. He is stumped as to what could be causing my pain. before the surgery I could reach behind my back to tuck in my shirt, etc, no I can't. Any suggestions as to the cause