Equine motion is very complex. Unlike people, horses require the use of every muscle, every ligament, every bone and every joint in the body to take one stride.
The shape of the equine hoof plays a very important role. Shape affects the biomechanics of the horse's motion and gait.
Long toes cause problems with the integrity of the hoof wall structures and delay breakover. Breakover is the point where the heel leaves the ground while the toe is still in contact.
- A delayed breakover increases the amount of work required by the upper leg to move the limb forward. This can lead to subluxations in the upper part of the limb and in either the lower cervical or lumbosacral spine, depending on the limb involved.
- The delayed breakover also causes a longer stride length, which must be compensated for by the spinal column and upper portions of the limbs.
A short toe places the sole and underlying structures at risk of excessive trauma and causes breakover to be too early. This will result in a short stride that increases degenerative forces in the lower part of the limb with each fall of the foot. Short strides must be compensated for in the spine and upper parts of limbs.
When a horse walks, a leg is picked up, flexed, brought forward (swing) and grounded (impact). The leg then supports the weight of the horse as it extends backward against the ground (thrust) and reaches breakover, leaving the ground for the next stride. In preparation for the stance phase, all the joints of the lower limb are extended during the latter part of the swing phase. This protects the joints from the concussive forces experienced when all the horse?s weight comes in contact with the ground. Since the horse cannot choose which part of the swing phase to eliminate, anything that shortens the stride length eliminates the extension and protection of the joints of the lower limb.
This total body involvement required for movement helps explain why a problem in the neck can affect rear leg motion. The more you learn about the complexities of equine biomechanics the more you start to understand the importance of spinal health to your horse's well being. Your AVCA certified chiropractor should start his examination at one end of the spine and continue checking all of the joints in the spinal column. They are trained to then check for correct motion in the joints of the limb down to and including the coffin joint. Find a certified chiropractor near you by looking at http://www.avcadoctors.com/ .
Dr. Bill Ormston graduated from Iowa State University College of Veterinary Medicine in 1988. After attending Options for Animals in 1998, he received certification from the American Veterinary Chiropractic Association and began using chiropractic to treat his animal patients. Jubilee Animal Health is a mobile mixed animal practice in the Dallas Metroplex area, using mostly alternative methods. Dr. Ormston is one of the founding instructors of the post-graduate course in Animal Chiropractic at Parker Chiropractic College in Dallas. He has lectured nationally and internationally on Animal Chiropractic and biomechanics, and gait analysis in the quadruped. Bill and his three teenagers, Riley, Philip and Jessica, live in Celina, TX, with 2 dogs and 4 cats. Contact him at email@example.com