A little Friday afternoon advice for you. If your dog appears to be uncomfortable, he's standing with a "hunched" posture and his tail is tucked down between his legs, FORCING him to swim in the backyard pool as "hydrotherapy" and then applying compresses to a random place on his back (alternating between cold and hot) several times over a few hours, isn't really the recommended course of action.
"And why compresses at this location on his back, do you think he injured that area?"
"I don't know, I don't think so. It just seemed the right place to do it."