Why There Is Difference In Bones In Both Shoulders?

My husband was in a car accident a month ago and xrays show torn muscle around shoulder joint. While giving a gentle massage I noticed the difference of his shoulder on one side seems to have bone higher and closer to the skin than the other side. He is also very tender on that right shoulder. His age 56 never had problems b/4 accident. Things feel out of line to me, from what I can feel, the right side muscle isn t surrounding the bone as much.