This entire document is copyrighted © 2008 by Martin D. Kenny and The Hoof Redevelopment Center All rights reserved. Copies may not be made without specific written permission. The key to reversing distortion of the hoof capsule is understanding physics. For too long, our industry has looked at cadavers for answers to alignments of structures (or lack there of) with little regard to how they interact in the live horse. As Newton’s 3rd law of motion states, “For every action there is an equal and opposite reaction.” That being the case, it is hard to understand much of what we profess happens in the hoof capsule. To give an example. We profess that a long toe creates a short low heel by the following process. The toe (ground surface) migrates forward, and the heel (ground surface) is pulled forward with it producing the classic “long toe low heel” in the horse. My research proves that this is not the case, and using Newton’s 3rd law, you can readily understand why the process is not as we profess. I have provided two photos below that will assist in understanding that as the toe migrates forward (at ground surface), the heel (at hairline) migrates rearward providing us with an appearance of the ground surface of the heel pushing forward. The foot does not have a “run under heel” but a “over run heel.” It is crucial to understand this if we are to ever produce consistent results in reversing feet of this type.
Let’s analyze the numbers on these two photos. Perp 3 on each is the vertical toe measurement Plate #2 is 100% of Plate #1 Perp 4 on each is horizontal distance from vertical at toe to the dorsal end of base Plate #2 is 115% of Plate #1 Perp on each is vertical measurement at the palmer end of base Plate #2 is 97% of Plate #1 Perp 2 on each is horizontal distance from Perp line to palmer aspect of hoof capsule Plate #2 is 86% of Plate #1 Analyzing further (by adding up horizontal measurements) we see that the total horizontal base of Plate #1 is 4.70 in. and Plate #2 is 4.89 in.. When looking at the horizontal length of the actual hoof capsule from base at Dorsal extreme of the toe to the Palmer extreme of the hoof capsule (heel bulb region). We see that this comes to an AP measurement of 5.64 in on Plate #1 and 5.72 in on Plate #2. This would indicate that Plate #1 had only 83% of the base of Plate #2. This being fact, would negate the Theory that the heel of the hoof capsule follows the toe as the toe is forced forward. The facts clearly show that while the toe migrated forward horizontally by 0.24 inches, the heel in relation to the limb above, increased horizontally the opposite direction in reference to the toe by 0.05 inches. At the same time, if you compare PERP 5 measurements in both plates you will see that the distance actually increased by 0.05 inches giving further indication that the heel does not follow the toe in migration. If it did so, this distance would not increase. In fact, by comparing the heel location of the shoe in relation to the limb above, we can readily see that the posterior portion of the base is actually moving rearward.   PLATE #1 The photo above is May 11th pre shoeing . Foot wearing a #2 St. Croix Eventer shoe	This Plate shows the bottom of the foot to the left at each shoeing. Clearly the heel is not being pulled forward as the toe (in other views) appears to be migrating forward.  In fact, even though the toe appears (photos to left) to be migrating forward, this view shows that in fact it is not doing so in relation to the frog. This would appear to indicate that the overall position of the hoof capsule; in regards to the bone column is adjusting its position as well as configuration. Further study is needed to draw reliable conclusions on that issue. I have written a series of three articles for the American Farrier's Journal on dealing with the subject of hoof capsule distortion, the first was recently published in the April 2009 issue and the next two to follow in subsequent issues. I will post those on this website as a PDF file after their releases. I have collected hard data on 80 horses that I used in a study about the role of nail locations and that will be published in the next AFJ. The last article deals with a very specific alteration to the bearing (foot) surface of the horseshoe that has greatly assisted me in improving and maintaining feet in a dynamic equilibrium state.
PLATE #2 This photo is August 31st pre shoeing Foot wearing #4 St. Croix Eventer®