Question: The last few days a weird sudden pain appeared in a very small area behind my left shoulder, near the skin. The 1st time I noticed was during sleep. The pain comes with a specific movement of the arm: when I try to make a full wide circle and my arm is on the stage of the circle behind me. It comes less strong with some other movements too.

The pain is very strong, sudden, localized and usually goes away very fast. It is a burning sensation and there is some weak residual pain afterward. It is becoming increasingly stronger the last few days and the area affected seems to be getting bigger.

I was not very worried but, just now, I have found a little star-like-shaped scar, maybe an inch across, a little bit raised.The skin is a little sensitive on that place. I have never had a scar injury in such place, only a dislocated shoulder about 10 years ago.

The pain seems muscular, it is not in the surface of the skin. But I could be wrong about the muscular part. Could be in an XXXXXXX skin layer.