The Horse

DEC 2018

The Horse:Your Guide To Equine Health Care provides monthly equine health care information to horse owners, breeders, veterinarians, barn/farm managers, trainer/riding instructors, and others involved in the hands-on care of the horse.

Issue link:

Contents of this Issue


Page 45 of 51

46 December 2018 The Horse | the other. This might be most obvious at the trot and can be influenced by the diagonal on which the rider sits. A horse might be adapting his movement to avoid discomfort when the rider sits on one diagonal. "You can get the impression of crook- edness in your horse if you rise up on one diagonal and then switch to the other and notice that the horse feels very different," Dyson says. Veterinarians have shown that in association with hind-limb lameness, there's also asymmetrical movement of the horse's back. Not surprisingly, some riders can feel this change. It might result in the saddle slipping consistently to one side, which can induce crookedness in a rider that normally sits straight. But some people naturally ride with slightly uneven rein tension—often due to their own laterality. They might inadver- tently carry one hand higher or rotate one hand more than the other. Crooked movement Horses might adapt to musculoskeletal pain by moving on three tracks (pictured here), instead of two, with the inside hind limb not fol- lowing the inside forelimb, for example, causing the rider to feel that the horse is crooked. "If the horse has overtly got one or both hind limbs on a different track to the forelimbs, then it's moving on three (or possibly four) tracks, and that's not correct," Dyson says. It can occur at the trot, canter, or both. A straight horse should move with his forelimbs in line with his hind limbs, without pointing a shoulder out in one direction when viewed from the front, says Marie Rhodin, PhD, Dipl. ACVSMR, an associate professor at the Swedish University of Agricultural Sciences, in Uppsala. Wayne Channon, BSc, ARCS, British international dressage rider and biotech entrepreneur, describes the crooked horse from the rider's seat. "A crooked horse is putting more weight on one leg or shoulder than the other," he says. "He's sometimes actually falling out over one shoulder, making proper impulsion impossible." Some horses could appear straight at the trot but not in the canter—or vice versa, adds Dyson. The horse's back movement in canter usually swings the rider's pelvis backward and forward, but some horses adapt their gaits due to pain and the rider feels a more rotational, jar- ring motion. Straightness: Why Does it Matter? Riders, trainers, judges, and veterinar- ians all seek straight horses. And it's not just for looks. For one thing, a straight horse is probably more sound than a crooked horse. "Generally, (crookedness) is an adaptation to lameness," Dyson says. However, science has yet to confirm that, Rhodin says. "We've initiated a big research project to collect detailed information on horse laterality, including crookedness, in combination with motion analysis to measure lameness," she says. "We're following 140 young horses over a two-year period to see if there's an as- sociation between laterality and lameness and how that develops with increased training." The pain might even be coming from the back, says Moorman. "Horses with lumbar or sacroiliac joint pain some- times don't want to use one particular hind limb," she says. "They might not bring that limb under the body quite as well, and they'll move their haunches one direction, so that the rider notices they're not moving in a straight line." Crookedness itself could lead to sec- ondary issues from stumbling, such as sprains or fractures, or from asymmetry, such as uneven leg strain, Channon says. While research on crookedness' perfor- mance effect is still lacking, researchers who are also equestrians rely on their own experience to find the link. "Straight- ness is very important for any kind of performance," says Rhodin, who's also a dressage rider, as is Dyson. Rhodin and Channon say straightness is particularly essential for most dressage movements. "The power generated needs to go through the center of gravity, but in a crooked horse that center of gravity is not in line with the power," Channon says, emphasizing mechanics. "I don't know any rider who wouldn't give straightness a very high level of importance. "It's simply impossible to achieve a classic extended trot with a bent horse," he adds. "How can you do that if his hind legs are going to the right or left of the front legs?" What's more, if a horse is crooked be- cause of pain, trying to force straightness through riding techniques could cause more pain, says Rhodin. And if subtle lameness is the core cause, it might even be impossible to force straightness, adds Dyson. Regardless of the reason, the problem compounds on itself if it's not corrected, says Channon. "Working one hind leg or one front leg more than the other all the time is inadvertently making the horse gradually more asymmetric," he says. "It'll just get worse and worse." SPORTS MEDICINE COURTESY DR. SUE DYSON Horses feel crooked to riders when they move on three tracks—when one hind limb moves on a different line than the forelimbs. A crooked horse puts more weight on one leg than the other

Articles in this issue

Links on this page

Archives of this issue

view archives of The Horse - DEC 2018