RIP Sports Town.
This is a devistating disease that has taken down so many of our horses. I don't think we will ever really understand a horse's foot.
This is an interesting but complicated website discussing it.
http://www.olympus.net/personal/pvd/pvd.html
Perhaps, Steve, you could get Dr Allday to give a simple explanation (if there is one) to the audience when he calls into the show.