My 10-year-old horse doesn't like to keep his hooves up long when you're picking them out, shoeing him, or doing anything else that requires his leg to be up. He's always done this even before I owned him, and I've had him for 4 1/2 years now. He's not lame, has great legs, hooves, and body structure. He acts like he's going to lose his balance and will just put his hoof down. Sometimes you can catch him and he will correct himself before he puts his hoof down. He picks it right up again and after a few seconds or minutes will do it again. He does this with all four legs, but mainly the front. He's been doing it more recently. Does anybody elses horses do this?