I have been leasing a 16 yr old green OTTB for a little over a year now. He has had constant cracks in his hooves. We have tried various hoof hardners and he is also currently on a supplement (gained consent from owner). Recently when I was at the barn I noticed how whenever I finish picking his hooves and release them, he hits the hoof wall against the ground before adjusting. Is there something I can do to prevent this from happening?