So the farrier came out today and was working on one of my mares. Started with her bad hoof(left front) and had done both rear feet and was getting ready to do her right front. He tried to pick up her left front hoof, she reared up started running backwards while on 2 feet and flipped over. Then she jumped up and kept freaking out, then the farrier tried to catch her and got his thumb caught in her halter and broke it. Her bad hoof is the left front, it is severely overgrown and curled(but getting better) it is weight baring, but she does limp most of the time. She ALWAYS rears when I try to pick up her right front hoof to pick it out to the point of she has flipped over a couple times, I'm 99% sure it is because she doesn't want to put weight on her bad hoof because it hurts.
Any ideas on how to get her to stop rearing?