Every horse in work?whether jumping, driving or trail riding?has to handle shock and concussion. Fortunately, the horse's hoof and leg are an amazing, intricately designed mechanism, made? for shock absorption. It works incredibly well, unless disrupted by conformation defects, injuries, or over use, all of which can result in increased concussion and, then, soreness or lameness. See?shock absorbing shoes sidebars.
NATURAL BUILD. The No. 1 thing you can do to reduce the effects of concussion is to ensure that your horse's hoof is properly trimmed and, most importantly, balanced.? If the horse isn?t trimmed properly, his natural shock absorbers can't work, leaving nothing to mitigate the concussive forces that run up your horse's leg every time he takes a step. The result is damaged joints.
A properly balanced hoof takes into account the horse's body and natural movement.? When you pick up a well-trimmed hoof, You'll see even, uniform heels. The frog is large, soft and in the middle of the sole.? You'll note some natural concavity in the sole, which helps the frog in absorbing concussive forces.
From the ground, the heels should be easy to see when viewed from the back (not under-run, meaning that they don't appear to slope under the hoof), and they should be uniform in size. The toe should be short, possibly rounded or squared, allowing for an easy breakover when the horse moves.? The hoof wall will expand slightly when the horse puts weight on it, which allows the sole and frog to work their concussion-absorbing magic.
We're strong supporters of going barefoot whenever possible, as barefoot horses have good natural shock absorption, to a point. A healthy frog acts as a shock absorber. However, hard riding surfaces can wear down hooves too quickly, so that the frog?s natural shock absorption becomes overshadowed by secondary excessive, painful sole pressure. What all this means is what your horse needs depends upon his build and the work you're asking him to do.
MINIMIZING SHOCK. Not surprisingly, most concussion-related problems involve the joints of the lower front legs. Healthy joints have cartilage that cushions the adjoining bones. When cartilage degenerates, the joint?s natural shock absorption lessens and the bones rub against each other. A horse with short upright pasterns and/or an upright shoulder angle will experience more concussion than a horse with a better build.
The other part of the horse's shock-absorption system is the arrangement of tendons and ligaments that ?spring load? the leg. When this system is injured or over-used and fatigued, abnormal forces can't be properly dissipated.
Well-conformed, healthy, fit horses?remember, the bones, tendons and ligaments are the last part of the horse's body to become fit and conditioned?generally don't need manmade shock absorption devices, unless they?re asked to work on hard surfaces for long distances. Even then some horses do just fine, as concussion in moderation stimulates strong bones and joints.
One of the most important things you can do to minimize the wear and tear on these joints is to feed a joint nutraceutical. In fact, these products do more to prevent the start of wear than they do to repair it. The time to begin feeding joint nutraceuticals isn?t when you start seeing signs of arthritic problems, it's as soon as possible.? Joint inflammation is a degenerative condition, meaning it worsens over time. The longer we can prevent its start, the better.
Consumer note: Be wary of the less-expensive products here, as they may not include therapeutic levels of these ingredients. Our January and February 2012 issues include the ingredient levels you need and recommended products. (Free online to subscribers at www.horse-journal.com.)
ARTIFICIAL SHOCK ABSORBERS. If your horse needs help reducing the ill effects of concussion, the simplest solution is to place a generic leather or plastic pad between the hoof and shoe. Although the force reduction offered by these products is marginal, it's an inexpensive, useful first line of action. Either material will do the job, but a new leather pad will conform better to the horse's hoof.
If you need more support, other synthetic pads, like the Castle Plastic Impak pads, have shown via durometer testing to have superior shock absorption, compared to generic plastic pads.
You can also find specialized shoes made with a metal core and a poly urethane or rubber molding on the outside. The advantage here is increased thickness of concussion dampening material, hence more shock absorption. There are several shoes on the market that offer this (see chart on p. 5). The most common disadvantage we see is lack of durability due to their softer material, meaning the shoes may show wear faster than steel shoes.
Plastic shoes can offer a good amount of shock absorption. They can be nailed on like a metal shoe or attached with a special glue.
Using a glued-on cuff-type shoe, which has an adhesive fabric that goes higher up on the hoof, with a soft rim pad provides excellent shock absorption. The soft pad between the hoof and shoe would compress too much to stay secure if nailed, so gluing this shoe on the hoof works well.
You may also wonder about aluminum or copper shoes, which are expensive options. We know aluminum and copper are softer than steel, but we haven't seen any reliable, unbiased proof that they offer any significant shock reduction, and they?re expensive.
As technology offers new materials and designs, innovation continues to offer shoes with increased shock-absorbing capabilities.? We've seen experimental shoes that have a spring-loaded design like some athletic shoes and a ?sandwich? design with rubber between the top and bottom halves of the shoe.
Additionally, shock-absorbing hoof packings can be combined either under pads or as a poured in pad, to further enhance shock absorption. Equi-Pak, Sole-Pak, and Sil-Pak from Vettec are used for this purpose. These are all good products, but each has a different level of firmness so the farrier should decide which may be the best choice for a particular horse.
BOTTOM LINE. Concussion plays a positive role in developing strong bones and joints, but the forces must be absorbed in a healthy way. However, conformation defects concentrate the concussion instead of distributing it evenly, which is where problems begin to surface.
Pads and non-metal horseshoes provide a reduction in concussive forces, so the useful life of a horse may be extended by using shock absorption proactively to manage the ill effects of conformation defects or competition/work demands.
Note, though, that if a horse is lame without anti-concussion horseshoes, it's likely not safe to use that horse for jumping or speed work. You must start with your veterinarian here for a diagnosis to know for sure what's wrong.
Article by Contributing Farrier Editor Steve Kraus.