Palmer Angle
15 July 2022
What angle is important with the Ross Smith Center of Balance Horseshoeing Method?
Palmer Angle is the one angle that I will talk about in relation to the COBIT and the Ross Smith Center of Balance Horseshoeing method. It is now becoming common knowledge that the angle of the bottom of the coffin bone in relation to the ground surface should be 2 to 4 degrees of elevation. Why is this important? How can the COBIT help you find it?
When you bring breakover back to where it should be using the COBIT and get the support back, the long and short pastern will align themselves with the coffin bone. For years we were always trying to line up the coffin bone with the pasterns. The horse’s leg would be X-rayed. We were told to put wedges on or more heel is needed, which actually made it worse for the horse. We thought it was all we could do to help. During our research we noticed that when the weight bearing surface is centered around the center of balance on a horse’s foot the long and short pastern would line themselves up. I always used to look at the pastern in X-rays but I do not pay attention to that anymore. I now set the bottom of the foot properly with the ground. If you go back to X-ray the Palmer Angle, you will find that the pasterns will begin to align with the coffin bone. This can take place within ½ hour of trimming/shoeing. If you give your horse a day or two to get used to it, the pasterns continue to align and suspensories and tendons become correctly placed allowing the leg to function the way it was designed. The proof is in the horse. If the horse does not like it, he will not perform.
It took me over three years before I finally agreed on the distance of 2 inches from center of balance to the toe of a horse. We X-rayed a number of good footed horses trimmed up nice and those horses had ¼ of an inch more foot to the rear of the center of balance than they did to the toe. They were already set up to breakover to succeed. That is how the COBIT finds both breakover and buttress of the heel as it is calibrated to find it through the position of the slots.
It is equally important to achieve the Palmer Angle on all horses. For example, what happens on a foundered horse is that the coffin bone rotates, this angle increases to 8 to 10 degrees or what ever it may be instead of carrying weight on the whole portion of the horse’s foot. The plantar cushion which provides a lot of weight bearing for a horse will shift all of it to the toe of the horse. The coffin bone will then go to the sole of the foot. The coffin bone gets so close to the ground because of this change, the horse will become foot sore.
You trim the heel as low as you can to try and get it close to the correct angle. When you will achieve the correct angle (between 2 and 4 degrees) the horse now carries weight on the full portion of the coffin bone instead of just the tip slicing downward which also helps the separation of the lamina which is what founder is. For a foundered horse always start trimming at the heel and do not touch the toe. If you do start at the toe, you will make the horse very sore.
Depending on the situation you face with a horse with wrong angles and bad heels it may take a couple of trims/shoeing to achieve the 2 to 4 degrees required for the correct Palmar Angle. Eventually they come back, the heels become healthier, the foot is now centered over the weight bearing surface of the foot and the horse is sound and happier.
How do the long and short pastern align with the coffin bone?
By moving the toe and heel back in relation to the coffin bone a lot of pressure is then relieved from the tendons, which allows the fetlock and rear of the leg to rise. When the fetlock rises up and moves forward it allows your long and short pastern to also rise up and move forward. This movement takes a lot of pressure off your deep flexor and suspensories. The suspensories are very important as they are what keep the fetlock of your horse from actually hitting the floor when you are in extreme conditions, jumping, turning or whatever it may be. The fetlock can only go so far down and the suspensories will stop the fetlock from going farther. Once the suspensories are back into the correct position, the pasterns align with the coffin bone. The fetlock and pasterns now have more flexibility to drop down before the suspensories become tight and overflex the joints.