When we got Kali, we knew that we were taking a chance on her. She had been mildly lame on and off and that was why she was looking for a new home (it's sort of a running joke since most of my horses came to me with hoof issues). She was due for a trim when we got her and she had some hoof flaring that I took care of right away. I am slowly removing the flares each time I trim which is every other week. She had short toes and high heels in the front which have been resolved. She had very flat feet in the back with bad outside flares and very thick frogs (thicker than any I have seen before). I wasn't comfortable trimming the frogs since they needed so much so Craig begged the farrier to do it (I do my own trimming but have the farrier do them every once in a while to make sure that I'm doing the right thing). He trimmed the frogs on all four feet and found something embedded in her hind left foot at the heel, next to the frog. He's not sure if it was a rock, a nail or a stick (he couldn't tell) but it was way up there and had been there for quite a while. It was deep enough to bleed. The hoof had encapsulated it and the frog had grown over it. He thinks that this would have definitely caused her intermittent lameness. I e-mailed her previous owner and it was indeed her left hind that repeatedly came up lame (her vet and her farrier both missed it). T has been riding her lightly, hoping to get her back into shape.
Let's hope that she's on the road to recovery!