Susan Kempson may have caused the biggest single splash at the third annual International Hoof-Care Summit when she shared her theory on what is the initial event in laminitis — a theory that many farriers in the audience obviously felt mirrored their own observations.

Kempson, the first-ever “Burney Chapman Memorial Lecture” presenter at the Summit, is a researcher and veterinarian at the Royal (Dick) School of Veterinary Medicine in Edinburgh, Scotland. She is challenging what she called the current theory that holds that the initial event in the pathogenesis of laminitis is that atriovenous anastomoses or AVAs in the dermal tissues of the foot open and deprive the capillary beds of oxygen. According to this theory, this lack of oxygen — called ischemia — leads to the death of vital tissues and eventually to the mechanical breakdown of the hoof-suspensory system that characterizes laminitis.

Why So Little Progress?

“We all know that laminitis is devastating and common,” she told the audience. “There won’t be anyone in this room that hasn’t seen or dealt with it. But are we really any further along in preventing or treating laminitis than we were 25 years ago? Do we really understand what’s happening in the foot during laminitis?”

Kempson sees several problems with the AVA theory. AVAs are vessels that connect an artery and a vein and that act as shunts to bypass the capillary bed. She points out that AVAs are found in the skin and tend to be concentrated in the exposed…