Originally Posted by Mellow Mel
My horse has FOUR of those in all four feet. I have had the farrier out and vet out. Mine is due to being sored(twh) when he was younger and they sored him very low so when a small crack appears it grows like yours. It is a thrush magnet!!! This is what I have been told to do. I soak in epsom salt, I use "tommorow" (made to dry up cow udders but used for thrush as well). Tomorrow has a syringe on it so you can get it up in those cracks and not only does it get rid of the thrush it also seems to dry out the cracks and make them smaller. My farrier will also take cotton soaked in thrush buster and put them up there for a few days(i pull it out). It takes a LONG time for those cracks to heal....there is also a new product that I am going to try, I forgot the name, I will send to you when I get it. Supposed to help close the cracks.
I have read about this online, I was doing some research on it because I was curious. It seems like this helps a lot of horses!