WWhen ever my dog has that problem, i always give it a good rub (massage) from the top of the leg to the bottom, its easier if the dog is laying down, so just do it after they come home from a walk and settles down its much easier, start off feeling different areas of the injured leg so it might give you a clue as to where the pain is being caused, as if you poke one place and the dogs leg responds its possibly that area, do a quick check around the bones and the hip bone just to be on the safe side, give it a quick rub down a few times now and again throughout the day, with gentle stretching