Michael J. Wildenstein, resident farrier at Cornell University’s large animal clinic, has approximately 400 different types of therapeutic shoes hanging on the wall of his clinic. Each one, he says, was made for a particular lameness or disease problem to fit an individual horse: aluminum shoes for a fatiguing jumper, plastic shoes for an endurance horse, rubber shoes for a carriage horse, titanium shoes for a horse who wears down its shoes too fast, glue-on shoes for thinned-walled horses. About 98% of them are nail-on shoes. His arsenal also includes bar shoes, shoes with frog supports, plastimer plastics for cracks, acrylics for hoof reconstruction, pads, metal plates, and even regular steel shoes.