ok, do you have any vet wrap? If so, wrap the lower portion of her leg from the knee down and try to get the top part of the hoof. Not too tight that it cuts off circulation. If there is no cut, scrape, thorn or other identifiable injury, she may have just sprained it. I just had this happen with mine. She is a boer and weighs 170 pounds. I gave her three 325 mg aspirin twice daily crushed in her feed for four days and checked the leg for swelling. keep and eye on the vet wrap so she isn't eating it and for tightness.