WHY HORSES lean is a question probably as old as horsemanship. Some say they’re curled to the left in the womb, others explain it’s due to Coriolis force. Still others say it’s really due to always handling them from the left.

The Woody model helps us understand that horses lean because it’s the easiest thing for them to do.

In terms of physics, there are three “stable” positions in anything that can lean away from a center point, such as Woody or a playground teeter-totter. Two of these positions, all the way to the right or all the way to the left, are most stable. The third position —balanced exactly in the middle—is also stable once it is achieved. It’s the slopes that connect the central position to the end positions that are unstable.

Your horse works the same way. It’s very easy for him to allow his chest to slide to the right or left. He can also be very comfortable and expend little effort if he goes straight, balancing exactly in the middle.

What most horses under saddle do is try to hold themselves halfway between. This is “out of balance” and causes bracing and stiffening, heaviness to the leg and to the hand, strain and muscle soreness. If the horse is ridden day after day while leaning, out of balance and “braced,” it will result in crankiness and behavior problems and finally in hoof and limb deformities and lameness.

Eye Dominance

As stated in part one of this series (pages 47 to 54, December, 1999 issue), all horses are either “left-leaning” or “right-leaning.” The choice of left or right is largely due to eye-dominance or the preference horses have to scan objects first and longer with one eye.

Eye dominance is the direct result of brain anatomy and development and originates at one of the earliest phases of fetal life. So there is really no hope of eliminating a horse’s tendency to lean. This is why straightness must not be mechanically forced with training devices, strong aids, uneven trims or pads or shims applied to only one foot. It is well within the rider’s power, however, to cause the horse to become functionally ambidextrous, just as a right-handed person can learn to throw a lasso or baseball with his left hand.

Horses like to go straight after a certain point when they are consistently well-ridden and handled and will perpetuate it themselves. They only need human help to “get out of a rut.” The farrier must function in the same way to support the horse—with orthopedic insight.

Eye dominance manifests itself as strongly as it does in horses partly because of the way they focus their eyes. The human eye has muscles which “squash” the lens and the whole eyeball, lengthening the distance from the lens at the front of the eyeball to the retina, or image-receiving screen, at the back. Shifting from far to near focus in humans means activating the “squashing” muscles.

Horses have the same muscles, but they are vestigial and nearly nonfunctional. They use their long, flexible necks like a boom to achieve mechanical focus. To focus his eyes, your horse simply moves his head. (People’s eyeballs are mounted on the front of the skull, and there’s a large overlap between the scan of the right and left eyes.) It is thus easy and natural for horses to scan objects with only one eye.

Horses that lean to the right may lead with the right eye or may square the head and both eyes in the direction of travel. A horse that leans to the right, however, will very rarely lead with the left eye and will object strongly (due to pains in his neck) if the rider forces him to do so.

Eye dominance can be lessened and the degree of straightness in the horse increased directly by calling the attention of the nondominant eye and indirectly by addressing the horse’s pattern of leaning. This is where good, orthopedically-based farriery interacts with superior riding technique.

Patterns Of Compensation

Woody demonstrates the simplest pattern of physical compensation for eye-dominance. This pattern is not common in the lighter breeds of horse, only occurring when an animal of phlegmatic temperament doesn’t mind approaching things with one eye leading and the other trailing out of focus and always deficient in “life.”

This pattern results in the grossest asymmetries in foot and shoulder development, the grossest lugging on one side of the bit and a strong tendency to drift, crab or stagger obliquely sideways.

At the subtle extreme lies so-called “rein lameness” which is slight but chronic asymmetry in movement. This results from the interaction of the horse’s leaning with hands which are trying to “fix” an asymmetrical feel by continuously pulling (holding) the animal’s head “straight.”

No horse can be truly straightened by pulling on the head or by blocking up one foot. These approaches result in a mechanical imitation of straightness.

Figure 1 shows the most common pattern of physical compensation. To achieve it, the horse begins by leaning (for example) to the right. Since he is not comfortable leading with one eye, he squares his head in the direction of travel. Due to the righting reflex, his pelvis squares itself to the head. This results in an S-bend which throws several “kinks” into the horse’s spine.

If allowed to travel this way, the inner aspect of each spinal curvelet will soon be the site of chronic low-grade muscular contraction or “guarding.” The pattern produced is the classic “checkerboard” addressed by both osteopathy and chiropracty.

One occasionally finds more complicated patterns of compensation, especially with dressage competitors who are schooled to the idea that in order to “round up,” the horse must be driven forward into a fixed hand. Beginning from either pattern, this policy will double or triple the spinal kinks. I’ve worked with dressage horses where every laterally mobile intervertebral joint was kinked and in which every peri-vertebral muscle segment was hyper-reactive and sore.

This merely serves to point out the danger in taking one adage from the European literature literally—that the horse must go “calm, forward, straight.” This order cannot and must not be followed. Though many have tried, no one has ever made a horse straight by driving it forward. The task of making a horse straight is like trying to drive a trackless train forward from the rear. If the train’s cars are initially out of alignment, no amount of pushing will remove the kinks! Before it can efficiently move straight, the cars have to be properly aligned. To be aligned, they have to be separately moveable (the joints between them have to be supple). The proper order of training is therefore: calm, supple, straight, strong and forward.

Strengthening A Crooked Horse

I’m going to convey one of the most basic “secrets” of horse training, one which few people clearly understand. The first person to discuss it thoroughly in print was François Robichon de la Guérinière, in the 18th century.

Even with a “Woody” model to play with, you may not at first understand this idea. It will be helpful if you get down on all fours and crawl, imitating a horse.

Since you have a collarbone, here’s an operating rule so your imitation of the horse will be as good as possible: when you lean, keep your shoulders parallel to the floor. Don’t dip down on one side, keep your back flat and the line of your shoulders horizontal.

Try leaning first to the right, then squaring to center and then to the left. Compare how it feels in your body to lean right vs. left; in many people, as in many horses, there’s a noticeable difference.

There are two techniques for straightening.

Elementary Technique: If the horse is inclined to lean to the right and if he runs into something uncomfortable when he gets there— such as a light tap with the bight of the reins or the rider’s boot tapping him at the girth—he will immediately move back toward the center.

This method is direct; the lean is felt and manifested through the shoulders where pressure is directed.

The advantage of this method is it’s easy for almost any rider to do effectively. Riders can also play with getting the horse to shift from one shoulder to the other to improve their “feel” for crookedness.

The disadvantages are that doing very much of it is likely to irritate the animal. Even after “correction,” the horse will always within a few strides drift back into his old pattern. This maneuver is therefore merely a class exercise.

Despite the horse’s peculiar shoulder anatomy and concomitant tendency to lean through the shoulders, the cause of the problem does not reside anywhere in the forequarter. Leaning is caused by asymmetrical use of the hindquarters!

The method that addresses the hindquarters is called “the master’s way,” and it offer a cure. Proceed as follows:

Master’s Technique: If the horse is leaning to the right, find the time in the stride when the horse’s right hind foot is all the way back—the instant before it’s picked up. Just as the foot begins to swing forward, stimulate it to change its flight path from where it would have landed (to the right of the rib cage) to a point directly under the animal’s navel.

The total differential in position will not likely be more than 6 inches; usually it’s more like 2 or 3 inches. Light aids are all that are required, although timing them correctly is essential.

When the horse’s right foot lands under the navel and begins to bear weight, it causes the animal to rearrange its body and balance around that leg.

This is what Robichon de la Guérinière termed “engagement of the hindquarters.” It is a small lateral movement, not one that emphasizes (as the modern dressage school does) the back-to-front motion.

To clearly understand the master’s way, get down on all fours. Without attempting to do anything “unnatural” with either leg, crawl forward while leaning right. Notice how you drift to the right. While still leaning right, crawl forward. Each time your right knee swings forward, place it under your navel. What happens through your shoulders?

In the “master’s way,” the hindquarters reposition the forequarters, eliminating the “lean” and all of its side-effects throughout the body.

This is why shimming or blocking one hind foot (so long as it is the appropriate one!) generally “works” better than similar treatments applied to the forefeet.

What To Do

Observe. Remember. Compare. Visualize. Go to bed thinking about this and get up thinking about this. Be absolutely honest about what you see, even where the pattern you detect seems to contradict the pictures shown in this article (that’s how paradigms get improved).

Educate yourself. Work out the thought-problems presented in the captions. Build a “Woody” model and carry it around in your truck. Get together with owners, trainers, veterinarians and other farriers and hash this out.

Woody will not only help you see the pattern of compensation as a whole, but will help you learn how to create trims and shoes that best support each horse.

Educate your shoeing clients. Encourage them to supple their horses and to ride them straight. Make copies of this article and give them to trainers.

Encourage them to take classes in anatomy and biomechanics. As they begin to understand, crooked stances and odd feet will diminish or disappear.

So will unnecessary shimming. Continue to trim and shoe feet according to the principles taught by master farriers as these principles are essentially orthopedic