Q: My question is about break-over and concussion. Where I live, we have had a long and very dry spring, summer and early autumn, so the ground has been rock hard for months and lots of horses (including mine) have jarred up and become sore. A friend of mine has a new farrier, though, and he has told her that the whole ‘hard ground causing horses to jar up’ thing is a bit of a myth, as horses have evolved to run for miles over hard ground. He says that so-called concussion issues are actually breakover issues; in soft ground the toe digs in a little but when the ground is hard this cannot happen and the horse starts tripping and must use its shoulder in a different way. Therefore it’s incorrect shoeing causing a mechanical issue rather than the hard ground in itself causing a problem.
It seems to me that trotters/pacers work hard, fast and frequently on hard surfaces, and they don’t seem to have the soundness issues that sport horses do.
Can you please give me your opinion on this?
DM, Auckland
A: Sorry to hear that your horse is sore. Jarring up can be a very real problem and is most certainly closely associated with prolonged working on hard ground and the related concussion effect.
Getting the breakover right is vital for the optimal performance of a sport horse and should be taken very seriously. It will also play an important role in reducing the likelihood of injury, certain lamenesses and to a certain extent, jarring up. However, if the breakover is correct then more focus should be put on the hard ground and how to reduce the effect that it is having on your horse.
I don’t always entirely accept comparisons to wild horses and their ability to do this, that or the other. Whilst it is very useful to study and attempt to understanding of the wild horse, there are significant differences to the horses we have in the paddock and ride. Because some horses survive in the wild doesn’t mean horses in our care should not experience certain conditions.
There are a number of things that can be considered when attempting to reduce concussion. I’d recommend talking to your existing farrier about what he thinks are worth trying.
The hoof capsule has evolved and has certain structures which have highly effective shock absorbing functionality. This includes the digital cushion (encapsulated within the hoof), the ability of the horny hoof to expand at the heels upon loading, the horny frog and so on. To ensure these structures are functioning satisfactorily then correct hoof balance is important. Specifically and in particular something that is overlooked or misunderstood is the importance of a hoof size which allows the hoof to function. In recent years, there has been a desire from some owners and farriers to make the feet as small as possible. Having a hoof that is too small for the horse can have a very negative effect on the shock absorbing ability of the hoof in the long-term. An abnormally small hoof will usually have a lesser surface area on the solar surface than a horse with an ideal hoof size. A smaller surface area for the hoof will mean less area for the horse to spread the forces around. As a result, a smaller area will likely limit the ability for the hoof to expand compared to a suitably sized hoof.
Similarly, a hoof that has been over-dressed and too small is likely to be more upright. This will impact on the amount of concussion that is placed on the foot (and transferred higher up).
Trotters and pacers work on various surfaces (not always hard) but also the fact they are standardbreds means they can possibly handle more than certain other breeds. Horses begin racing at an early age, most have finished their careers within a small number of years (often before any lameness issues are observed) and those that don’t handle the workload, don’t stay at the trainers long. In comparison, those of us who jump, event or compete in dressage often have variously bred horses and are worked for a number of years – some developing conditions related to concussion. Generally speaking (although not exclusively), more care is taken with the breeding of racehorses. Conformational abnormalities in racehorses can have a dramatic effect on the sale price whilst we too often turn a blind eye to many imperfections in our sport horses.
If your horse is jarring up when the ground gets hard then I’d be looking at ways to reduce the concussion. This might include shock absorbing options (pads for example), the options for working on less hard surfaces as well as hoof size/balance. The Equithane range of hoof materials produces some worthy results for many horses on hard ground in NZ – talk to your farrier about these.
David Hankin Dip.WCF
This question and answer first appeared in NZ Horse & Pony magazine May 2010
Farrier Blog 
I dont think your friends farrier’s hypothesis re: breakover being the sole reason for concussion sounds very reasonable to me. If this was the case a farrier could solve any concussion problems simply by always using old shoes that were nearly worn out at the toe area by that horse, . besides a horses front feet land heel first then roll forward over the toe, so it would stand to reason that the greatest point of impact and concussion would be at the heel area were the foot disperses and absorbs the impact, remember up to now we are only talking about the foot hitting the ground. Ok now have say a 500kg horse travelling at say 10 kph and about to place all its weight on this one foot, you can see the problem, lucky for the horse he has a suspensory apperatus to take care of this. So i myself can not see how doing anything at the toe could help. dont worry about anyone else horse just workout what your horse needs, more or less hoof moisture, more foot left on when shod, a different type of shoe, is the frog too big for the foot size, plus everything David Hankin said. Good luck with it