Today when I was brushing Baron I noticed that he had a sore on his hindquarters. I took a mental note and am going to tell my mom about it when she gets home. I kept brushing him and once I got to his back I noticed he started kicking himself (like when you scratch a dogs belly and their leg starts going). Where his foot touched him was right where his sore was. What can I do so he isn't hurting himself when I brush his back? His nails are already kept short. I can't not brush his back with another brush because he tends to do this with my slicker and comb I have for him too. I don't know how relevent this info is but he's a 10 year old GSD who only just started to be ticklish about his back and I was using a rake on him. He was at the vets a few months ago(May or early June) and they found nothing wrong with him.