I have a small 5 year old mutt. At a young age he was ran over due to climbing the fence. Leaving him with his left arm a bit out to the side. Recently we got a new dog a pit bull mix. My dog and he played a lot. But yesterday I noticed that he wasn't really playing so I went to check on him and he would whine when the touched his arm pit area in the same hand that he got hit in the car accident. So I started moving his hand around and no whine. I did notice that his arm was more to the side then usual. If his shoulder is dislocated how can I place it back in place?