This is the third in a series on straightness and its effects on the hoof.

Read "How Straightness Affects the Equine Hoof" and "How Leaning Affects Equine Anatomy"

Whereas structurally asymmetrical horses are rare, horses that are in the habit of leaning and traveling crookedly are nearly universal in the domestic horse population. In this article, my purpose is to demonstrate crooked carriage in a variety of different riding and training contexts and various horse breeds.

Knowing the signs in both horse and rider that they are not in the habit of moving straight is certainly relevant to the farrier’s ability to give great service. I begin by asking you to consider the horse in Figure 1. It’s a useful image because the animal is loosely tied to a rack; nobody is trying to pose him in any fancy way, nobody is pulling on his head, nothing is causing him to tense up, and the only irritant present is enough flies to make him want to swish his tail. The owner took the photo and sent it to me saying that it’s a 15-year-old Missouri Foxtrotter gelding. He enjoys riding this horse but reports that he “has no left lead” and asks for advice on how to fix this.

It’s always good to begin by assessing structure. I see little to complain about in context of the horse’s use, which is mainly trail riding. He’s a little upright through the knees,¹ but the joints are plenty big, properly formed and largely free of puffiness or other signs of wear and tear that might be expected in a horse of this age. The fore pasterns appear steep and both the fore and hind hooves are a little out of anteroposterior balance, i.e. slightly longer in the toe than they should be. However, it might be that the horse was tied up because the farrier was expected that day. The angles at the stifle and hock are correct. I appreciate the big pelvis, broad loin coupling and reasonably smooth topline. The withers are sufficiently prominent. The head is beautiful, and the shoulder is good — nicely angled with a clean shoulder bed. The neck is long enough and nicely shaped, although my impression from the play of the muscles is that it’s a bit stiff.

A 15-year-old Missouri Foxtrotter gelding. Photo by: Philip Mell

What can be seen in this photo, however, leaves out some things that we would like to know. Few prospective horse buyers think to examine or photograph a horse from above, i.e. by standing in the bed of a truck and shooting down on the back of the horse that’s standing square with its hindquarters facing the truck. Unfortunately, the gelding’s owner did not send me either this type of photo or well-taken front or rear views (Figures 2-4), yet they would be a great help in determining the training, rehabilitation or farriery needs of this horse. Although we don’t have those images, we can compare them with other horses and still be able to draw reliable conclusions.

A 9-year-old Paint gelding that’s structurally asymmetrical. Red arrows in the front view mark the heights of the elbow and the top of carpus; blue arrows show the orientation of the toes. Top views of the back are only useful if the horse is carefully squared up both before and behind because if he takes a step the back will curve so that it becomes concave on the side of whichever hind limb is advanced. Further, the head must be gently held directly in front of the center of the breast. Photo by: Philip Mell

Figures 2 and 3 are examples of horses with structural asymmetries like the ones we studied in our last installment (see “The Anatomy of Leaning,” in the March 2024 issue). Like the gray Foxtrotter, these horses also have trouble picking up or maintaining one canter lead.

A 9-year-old mixed warmblood mare that’s structurally asymmetrical. Like the Paint gelding in Figure 2, this mare’s back bears a curve that does not change to the opposite side when she moves. Whereas the Paint’s twisty topline is compensation for limb length differences, this mare’s is directly due to malformation of the vertebrae and/or a hemi-rib (“false rib”). Photo by: Leonie Kruse

The horse in Figure 4 also has some “lead trouble,” but her back, shoulders and hips are not those of a structurally asymmetrical horse but one that habitually leans. Notice that the degree of unlevelness that she presents is not outside normal limits (review the “normal limits” concept in our last installment). Note also how both her left fore and left hind hooves aim to the left, while the right fore and right hind aim straight forward — a stance that indicates that this mare habitually leans to the right.

Compare this with the Foxtrotter; three of his feet aim to the right, while the left fore aims straight forward. This indicates that he habitually leans to the left. Like the vast majority of horses, both of these have a “favorite” hock, which means they prefer to more heavily weight the hock (as well as the forelimb) on the side toward which they lean. Despite rumors to the contrary, I find that there are about as many right-leaning as left-leaning horses.

From the Foxtrotter’s “natural” stance and these comparisons, we can deduce what his habitual movement pattern is likely to be — he’s a left-leaning horse. However, I still have not answered the owner’s question — why is he only willing to take the right lead? One-lead horses are manifesting crookedness, but first, it’s necessary to look at the bigger picture to learn how most horses respond to the problem of maintaining their balance when a rider climbs aboard.

Aspect Ratio

The scariest thing that can happen to a horse is to fall. Modeled as a box on a set of stilts and viewed from the front or rear, the horse’s body is remarkably unstable. I drive a Hyundai Elantra, which has an aspect ratio — the width of the car multiplied by 100 divided by its height — similar to many subcompact cars.

Mine measures 67.7 inches from the center of the right front tire to the center of the left, and the car stands 54.9 inches high. This yields an aspect ratio of (67.7 X 100)/54.9 = 123%; in other words, the car is 23% wider than it is high. I also own a GMC Sierra half-ton pickup. This vehicle’s tires stand 78.5 inches wide, while it is 73.9 inches high, yielding an aspect ratio of 94.14%; in other words, the truck is 94% as wide as it is high. The higher the aspect ratio, the more stable the vehicle is, i.e. the less likely it is to flip over when cornering. Even trucks and all-terrain vehicles with the worst aspect ratios are never less than 80% as wide as high.

Now let’s model the same calculation using a series of horses. We’ll say that all of them are the same height at the withers. We’ll choose to have them be the average height for riding horses at 15 hands, 2 inches or 62 inches. We measure our first horse and find that its fore hooves stand 10 inches apart from center to center. Then we measure the three other horses, each of which stands 2 inches wider than the last, and calculate the aspect ratios for all four.

• Horse A: (10 X 100)/62 = 12.90%
• Horse B: (12 X 100)/62 = 16.13%
• Horse C: (14 X 100)/62 = 22.58%
• Horse D: (16 X 100)/62 = 25.80%

It is obvious that horses are much narrower for their height than cars, pickups or ATVs, and thus innately much less stable when cornering. Fortunately, they have a couple of advantages that automobiles do not. First, the brain and nervous system are highly integrated with their musculoskeletal system, which provides many feedback mechanisms that help preserve balance. Second, they can lean “into” turns in the same way that a motorcyclist can. This works fine so long as the footing is not slick, the speed is not too great and the diameter of the turn isn’t too small. Third and most importantly, horses have a flexible spine; they can use their long neck and their back to compensate for the angular momentum that causes cars to flip. This works fine so long as they don’t also have to compensate for a rider sitting on their back.

The center of gravity of an unmounted horse standing at rest lies at about the same height over the ground as its heart. The physics principles pertaining to the center of gravity are almost always misapplied by riding instructors, but this is one instance when the concept can be applied correctly.

A 16-year-old American Standardbred mare that’s in the habit of leaning to her right. Red lines show the unlevelness at the tops of the shoulders, points of shoulder, knees and hips; none of these exceeds 3.5 degrees and are therefore within normal limits, i.e. she isn’t structurally asymmetrical but merely carries herself crookedly. Blue lines are plumb; note the lack of unlevelness in the rear view. There’s a slight leftward “sag” in this mare’s spine to the left, just behind the withers. This develops in many horses due to constant mounting from the left without the use of a mounting block and will entirely disappear once care is taken to use a mounting block and to teach the mare to like being mounted from the right side. Photo by: Sarah Orloff

When a rider mounts the horse, the “composite” center of gravity is higher than in the unmounted horse (Figure 5). How much higher depends upon how tall the rider is above their seatbones. For our purposes, it doesn’t matter how much taller; all we need to notice is that, if the animal was tall over a narrow “wheelbase” when unmounted, functionally it’ll be even taller with a rider aboard. That means the aspect ratio will drop below what the given horse’s musculoskeletal, nervous and balance systems were looking for.

This is why if you observe youngstock being ridden for the first few times, you’ll notice that they stagger. They also stagger when being mounted. If the rider isn’t careful to keep her body close to the saddle as she steps into the stirrup, the colt or filly may not only stagger to its left but also try to run off or buck because it perceives this as the only way to avoid being pulled completely off-balance.

Most young horses eventually learn to compensate for the rider’s weight hanging off to the left during mounting by spreading their forelimbs. They also figure out — through trial and error — how to handle straightaways and curves while packing a rider, compensating at least well enough so that they don’t fall.

Compensation is, however, dangerous in the sense that a first compensation almost always requires a second one, and that one a third, ad infinitum. Most owners, and indeed most professional trainers, are unaware that many apparently “normal” actions of green horses are compensations.

The greatest biomechanical problem that mounted horses have is that they are mounted. Given this, it would be wonderful if people realized that horses must be taught how to carry a rider with ease and balance — nothing in their biology prepares them for how to cope with a rider on their back. What they need to be taught has nothing to do with either the much-touted “impulsion” or with any type of “maneuvers,” whether elementary or advanced. There’s only one way for a horse to carry itself and its rider easily and in balance and that’s to travel anatomically straight, whether on a straight track or on curves.

Straight Under Saddle

The rider’s job is not to teach the horse “things,” but to help it find and maintain its balance with a rider aboard through all changes of gait, speed and direction. It still will be compensating for the rider’s presence; in other words, it will not handle curves the same way when mounted as when it is at liberty. However, when it’s in skillful and knowledgeable hands, the horse will not be compelled to guess at what the best compensations will be but rather will be taught them from Day One.

Particularly, the horse will be taught not to compensate by merely increasing or exaggerating the spinal bend that it would prefer when unmounted. Until they have been trained to a high level, unmounted horses counter-flex the spine when cutting curves. “Counter-flexion” means that while the horse’s body as a whole moves to the left along a curving path, its spine does not conform to the path upon which it travels. Instead, it arcs in the opposite direction as compensation for the effect of angular momentum.

The degree of counter-flexion increases with speed and as the diameter of the circular track diminishes. If the horse does this under saddle, however, the rider’s center of gravity and the horse’s no longer line up (Figure 5). 

Aspect ratio, leaning, center of gravity and ways that riders attempt to compensate for a horse that moves crookedly; see Figure 13 for a real-life example. The view is from the rear. The horse half of this “centaur” is the gray box with legs below, shown leaning 5 degrees to the left and drawn with the most stable aspect ratio for equines of approximately 25%. Image B is probably the best rider compensation since the rider’s standing, unmounted center of gravity (blue dot) and his center of gravity when seated (green dot) both line up over the horse’s CG (brown dot). Compensation A induces the horse to step to its left, drawing it as it tries to stay under the rider’s CG. Compensation B weights the concave side, which is already lower, making it difficult for the horse to level its back and stop leaning. Photo by: Sarah Orloff

If the horse circles left, it flexes its spine to the right, so that the left side is convex and the right side is concave. This causes the ribcage to roll downward on the concave side, i.e. the right side of the animal’s back will be lower than the left side. This in turn forces the rider to compensate, and whether she hangs on for dear life while passively allowing her upper body to be displaced to the right (Figures 5c, 10b), tries to sit square in the middle (Figure 11a), or stands in the stirrups and shifts her shoulders toward the convex side (Figures 5a, 6b), the effect on the horse will be the same — to induce it to fade, or stagger, toward the convex side.

The author mounted on a supple horse that’s moving anatomically straight upon a curving path (A) and a student (B) mounted on a horse that is leaning toward its right and thereby moving crookedly. The arc in my horse’s back, from forehead to tail, conforms to the path upon which he is ridden; the student’s horse is counter-flexed. Note differences in the horses’ expressions — contentment in my horse’s case, irritation in the student’s. Photo by: Sarah Orloff

I mentioned earlier that green horses stagger when first mounted and ridden, even at a walk let alone at faster gaits. Staggering means that the horse is not swinging its legs parallel, or close to parallel, to the long axis of its body. Rather, if it leans to the left, both the left and right pairs of its legs must reach to the left (Figure 12). The right pair of legs may reach so far to the left that they cross over the left legs. Farriers will not be surprised to hear that such oblique protraction of the legs affects the location, duration and force involved in breakover of all four hooves.

If this is the only way the horse knows to carry a rider, even years after being broken in, the animal still will be moving off-balance all the time. Many riders get used to this feeling and call it “normal.” Rather than correct the fundamental problem, some may teach (or permit) the horse to travel along the track or around curves by angling its body (Figures 8, 11a). But neither of these approaches is desirable; they merely reflect the fact that the rider/trainer does not understand what straightness is and fails to grasp that the horse must be taught to carry itself and its rider straight before it can perform any maneuver or any type of work well.

Straight vs. crooked horse negotiating a corner in an arena, as seen from above. A, horse is anatomically straight on a curve of 8m diameter; B, horse anatomically straight on a curve of 20m diameter. In C, the horse moves crookedly with its spine counter-flexed. Photo by: Sarah Orloff

The images in Figure 6 are taken from photos of me instructing a student during a mounted session in the arena. We are negotiating a turn to the right with our horses moving,² more or less, in parallel. It’s “more or less” because my gelding’s body curves so that the line of his vertebral chain as seen from above conforms to the track upon which I am riding him (Figure 7).

In contrast, my student’s horse counter-flexes. I present this image so that farriers may study it to be able to realize what the horse is doing whenever they see one go around a circle or through a corner under saddle — it must be one or the other. Note in particular the gray dot that marks the place where the protracting hind hoof will be set down. My horse will set it down toward his midline, beneath his belly; my student’s will be set down wide of the body.

The same horse in various positions as it passes crookedly through a corner in the arena, as seen from above. Photo by: Sarah Orloff

Stepping under the body by bringing the hind hoof of the concave side obliquely forward and across as my horse is doing is called untracking, and it’s the basis for training the horse to go straight on a curve. Untracking causes my horse’s spine to conform to the arc upon which he is being ridden, and because this is so, he is moving anatomically straight. My student’s horse, by contrast, is not untracking; he is moving crookedly; his spine is bent the wrong way. He is “falling in,” i.e. fading, or even staggering, toward the convex side.

Horses moving crookedly. A, Peruvian Paso moving along the fence in an arena at a walk; B, Arabian gelding moving at liberty in a round pen at a trot. Both horses are counter-flexed and both angle their bodies to avoid getting near the fence. Photo by: Dr. Deb Bennett

This is shown from above in Figure 8 in the context of the “fence effect.” When they are ridden on the arena track or anywhere else fairly close to a fence, most horses seem to fear that they are going to hook a hind foot or perhaps their stifle or hip on the fence. Therefore, they orient their body so their shoulder and hip are equidistant from the fence. But because the horse’s body is wider through the hips than through the shoulders, it automatically means their spine will be at an angle to the fence. To maintain equidistance, the horse leans away from the fence and thus also maintains a counter-flexed spinal curve. It looks and feels to the rider as if the horse is bumping into an invisible force field emanating from the fence.

As the untrained and/or badly ridden horse approaches a corner, instead of tracking through the corner in balance as shown in Figures 7a or 7b, he will “fall,” fade or stagger through the corner as in Figures 7c or 8. Because the horse is falling through the corner, it feels to the rider as if it is pushing against her inside leg (the leg that is on the inside of the turn or toward the center of the arena).

Horses at a rodeo. A, Quarter Horse moving at a lope moving on a counter-clockwise circle on the left lead. B, Arabian counterclockwise at a run on the left lead. Both horses are strongly counter-flexed; horse B is so unbalanced that it’s in danger of falling; the rider has to cling on by clamping her legs to the horses’ sides and holding the saddle horn. Photo by: Dr. Deb Bennett

One of the errors being committed by my student in Figure 6b is her response to this — she knows well that the horse is supposed to “round out” through the corner, as my horse is doing, so she is trying to accomplish it by using her right leg to pry with all her might on her mount’s body. This will never succeed because the horse is much bigger, heavier and stronger than she is. No amount of human strength will be enough to shove or kick the horse toward the fence or crush a bend into it. Her forceful use of the leg does nothing but hurt and irritate her gelding (note the difference in my horse’s expression and hers). Repeating this mistake ride after ride compounds the problem because it teaches the horse to ignore the rider’s leg and that will eventually result in what is euphemistically known as “the bloody spur lesson.”

A, Quarter Horse warming up for calf roping. He is coming directly toward the camera at a slow lope on a track parallel to the arena fence. This horse is slightly counter-flexed and moves with his body at an angle to the fence. B, Arabian in an English pleasure class as he negotiates a corner in the arena. C, pinto Saddlebred moving at a walk down a paved road. Note the unlevelness of head, shoulders, hips, knees and feet of all three riders, and the counter-flexed spine in all three horses, which forces the animals to cross their legs in movement and alters the normal points of breakover. Photo by: Dr. Deb Bennett

More examples of the counter- flexion induced by fence effect are shown in Figures 9-11. I have selected these to show several riding styles and a variety of breeds as a way of demonstrating that avoiding the fence/shoulder and hip equidistant from the fence is nearly universal in untrained and/or badly ridden horses. Figure 9b shows fence effect in the context of a horse trotting loose in the round pen, which is “all fence, all the time.” The round pen is commonly misused by permitting or even encouraging the horse to relate to the fence this way, which teaches the horse to travel crooked. The proper use of the round pen — a powerful tool — is to teach the horse to untrack, to turn toward the handler and to come in at call, i.e. the basis for liberty work.

Front (A) and rear (B) views of a well-conformed, structurally normal and very good-natured Australian stock horse moving crookedly. Note how crookedly the rider sits. The horse crosses its legs as it walks forward and breakover on all four feet is shifted to the left. Photo by: Dr. Deb Bennett

Figure 11c is particularly interesting because the horse is being ridden down the center of a country road with no fence nearby. I happened to see this rider coming toward me, so I pulled over and started shooting. The rider was about a mile distant from me when I first saw him, and at no time until he came right up to me did his horse track straight.

The fence effect in this case is entirely visual. The horse is responding to the parallel margins of the road. He is also, however, leaning in his favorite direction — the direction he’s been leaning in since he was a foal nursing off his dam.

The rider is having a good time and is blithely unaware that his horse moves crookedly. Note how the crookedness of the horse unlevels, not only its body but that of the rider — waist, knees, ankles and feet. We’ll return to examine this image in more detail in our upcoming discussion of how owner/rider and farrier can work together to help a horse learn to move straight.

A warmblood horse being longed in the manner commonly seen. See the text for an explanation of the twisted posture that bad longeing technique teaches. Photo by: Dr. Deb Bennett

A more extreme example is presented by the rider and horse in Figure 13. This woman enrolled in one of my riding clinics, and when I asked her to ride her horse at a walk along the arena track, a very off-balance rider on a very crooked horse is what I saw. I said to her, “Are you aware that you’re sitting off to one side, with one knee higher than the other?” With raised eyebrows, she replied, “What do you mean? Of course, I’m sitting correctly. I’ve spent 5 years taking lessons from a certified instructor.” Yet, that instructor never once had mentioned to her that she sat off-center or that her horse moved crookedly. She would not believe me until I took these photos by standing directly in front and behind her horse and showed them to her. To her credit, she immediately sought out a better instructor. I saw her again the next year and both she and her horse had straightened out almost completely.

This case is a chicken-and-egg situation. I cannot tell whether the rider’s preference to weight her right seat-bone and thereby collapse the waist and curve her spine to the left came first and drove the horse to compensate, or whether the horse’s tendency to lean to its left, thus lowering the right side of its back, caused the rider to compensate. Perhaps it was some of both.

A horse must weight or “anchor” the right hind limb to depart on a left lead. This pair of drawings shows the difference in limb position and weighting in a trot (A) vs. a left-lead canter (B). The rider (not shown) deliberately asks the collected horse to lean one or two degrees to his right in view B, so that weight flows into the right hind limb. With the right hind limb anchored, the horse can easily depart into canter from any other gait. Canter departures require the horse to stand on the anchored hind limb for anywhere from half a second to about two seconds (depending upon the speed at which the horse is moving), while all three other feet are lifted in sequence. Horses that are not in the habit of using both hind limbs equally experience “twinges” in the non-preferred hock when they attempt this and this is why they avoid it. It’s also why thorough suppling, which teaches the horse to use its hind limbs equally and thereby to move anatomically straight, is so important. Photo by: Dr. Deb Bennett

Correcting the rider’s seat will not be enough to fix this; it is the horse’s tendency to lean that must be corrected first since the animal is much bigger and heavier than the rider. As soon as the animal is taught to carry itself straight, it will offer the rider a dynamically level³ platform upon which to sit and then most or all of the rider’s unlevelness will disappear all by itself. Meanwhile, every farrier who looks at these photos will recognize the abnormal orientation and breakover of all four of the horse’s hooves.

Straight on the Longeing Circle

Common although it is for riders to permit horses to move out of balance under saddle, it’s even more common when the horse is being longed (or worked on a 12-foot lead rope). Figure 13 is an excellent example.

Longeing is often used simply to let a horse blow off steam before it’s mounted, but it has more sophisticated uses — similar to round penning to teach a horse how to untrack and thus how to move in balance and ultimately, in collection.⁴

When longed in the manner shown, however, the horse is being taught to move crookedly. It not only tracks the circle with its ribcage counter-flexed, its muzzle is being pulled toward the center, inducing the head to rotate (twist) on the end of the neck, which puts an “S” bend in its spine. Note that this occurs from the mere weight of the longe line. Its whole body is fading inward (red arrow), while the outside hind leg performs a kind of “roundhouse” motion as it’s protracted (purple arrow). The inside hind leg looks like it’s untracking (blue arrow), but it’s not. Its location far under the body is due to the body leaning and falling in over the leg, not to the leg cutting under the body.

I’ll show the keys to correct longeing technique in an upcoming installment. My effort here is simply to remind farriers and veterinarians that accurate assessment for any purpose — i.e. lameness diagnosis or trimming or shoeing needs — is simply not possible on a horse that’s being hustled forward with an “S” bend in its spine.⁵

Indeed, in response to numerous instances of injury associated with longeing (suspensory pulls, collateral ligament sprains at the fetlock joints, tendon strains, splints), many veterinarians recommend that clients avoid longeing their horses altogether. The rationale is that “going around on circles is not natural to horses.”

The problem is not, however, that the longed horse travels a circular trajectory. Rather, unless longed correctly, its spine doesn’t conform to the track upon which it travels and it’s therefore not moving anatomically straight. The injuries listed just above are all associated with torque. In other words, while the head and forequarter are being pulled toward the handler, the handler is also making the mistake of “aiming” the driving aid at the haunches. The net result is that as the horse circles, its rump tries to travel a track wider than its shoulders, forcing its body to pivot around whichever forelimb is in contact with the ground, which creates the torque that leads to injuries.

“No Left Lead”

Now we can return to the Foxtrotter in Figure 1 with an answer for the owner as to why the gelding only takes the right lead. When my wonderful horse Painty was still alive, he and I often performed the demonstration shown in Figure 13b for students. For clarity, only the horse is shown in the drawing. In 13a, we are trotting forward on a straight line; in 13b, Painty is in the act of picking up a canter on the left lead. The image shows the first “beat” of the canter, or in other words, the leg that the horse must weight first to pick up a left lead, which is the right hind (if I asked Painty to take up a right lead instead, I would have set him up to weight the left hind leg).

Many riders lack an understanding of canter biomechanics; they think that a left-lead canter must be initiated by the left forelimb — or they have some other distorted theory. If the horse first understands that the leg aids mean for it to increase its energy output, all that’s necessary to get it to depart on a left lead is to set the horse up so that it bears more weight upon the right hock, as shown in Figure 13b, and then ask for the necessary rise in energy. It’s a two-step process.

Note that to depart upon a left lead, the horse must stand for the duration of a half-second or so with all its weight upon the right hind leg. You will recall, however, that we noticed that the Foxtrotter is reluctant to weight his right hock. He’s perpetually setting himself up for a right-hand (clockwise) bend by arcing his spine so that the concave side is on the right. He habitually stands and moves with more weight on his left hock.

I spend considerable time suppling my horses. I rode Painty through exercises requiring him to flex his spine first to the left, then to the right, until he was so supple that he could track a 10-meter circle at a canter with ease while carrying himself anatomically straight.

The master motion for such training is untracking, which soon segues into an age-old exercise called “expanding the circle,” in which the horse leg yields outward to its right while being ridden forward on a circle, then reverses direction and leg yields outward to its left. When this becomes easy, it will benefit the horse to be ridden on figures of eight, which consist of two perfectly round circles of equal diameter that are joined at a single point. In the step preceding X, the step at X and the step after X, the horse’s spinal bend changes because in these three steps, it changes from untracking with one hind leg to untracking with the other. It is the change of untracking hind leg — not anything that is done with the reins — that drives the change of bend.

The point eventually comes when I can ask the animal to change the bend or increase the degree of its bend anywhere, whether we are on a circular track, a straight track, or out on a trail ride. In other words, the day arrives when I have complete control over the horse’s bend, and therefore over which hind limb and hock the horse weights. At that point, it becomes possible to pick up a canter on whichever lead I specify from either a walk or trot on a circle, a straight line or out on a trail ride. Eventually, it becomes possible — in response to aids so light that they are invisible to observers — for the horse to pick up a canter from a halt.

This is the demonstration that Painty and I used to do (Figure 13B). Students need to see it because being able to do this should be a primary goal of beginning horsemanship; its “graduation exercise” so to speak. I want to provoke this question in people’s minds: what does it mean for the horse to carry itself and its rider straight, in other words, to have straight carriage? The answer is that it means the horse is supple; that the rider can ask for either bend at any time; and that, indeed, it’s a matter of no concern to the horse whether it travels to the right or the left because it no longer has a preference and is just as comfortable going either way. So long as the Foxtrotter gelding retains, and is allowed to retain, any preference to weight the left hock more than the right, it will be difficult or impossible to get him to pick up a left lead.

Many Manifestations

There is no space here to detail every training difficulty that ultimately stems from the reluctance to weight one hock/crooked carriage, but here is a list of the most common. It’s not a short list. To those who do not realize that crooked carriage is the root cause, most or all of the items on this list will continue to seem like unrelated difficulties.

• The horse approaches the handler or objects with its head cocked to one side/one eye “leading.”
• At a walk or slow trot, the horse seems to have a “flat tire;” one hind limb takes a longer step than the other.
• The horse seems mildly lame or “off,” but there is minimal or no head nod and the veterinarian cannot locate a particular lesion.
• Chiropractic treatment, acupuncture, acupressure or massage tend to produce improvement, but it is only temporary.
• The top of one shoulder and/or one hip is noticeably higher than the other.
• The saddle continually turns toward one side.
• Difficulty in finding a saddle that fits; no matter what brand or type is tried, the saddle will not stay in place.
• The horse gets a rub from the saddle on one shoulder and/or under the cantle on one side or girth galls on only one side.
• The horse is reluctant to turn or circle in one direction; stiffer to one side.
• Circle “shrinks in” to one side.
• The horse “takes” the bit on one side, “drops” it on the other; seems “hard-mouthed” on one side.
• The horse feels heavy or seems to lean against the rider’s leg on one side.
• The horse continually looks toward the outside of the round pen; swings its head and neck to the outside when cornering.
• The horse “falls in” or “drops a shoulder” when passing through corners.
• The horse will not take the track and/or will not move close to, or parallel to, the arena fence.
• The horse continually wants to come in toward the center, or crowds the handler, when going in one direction on the longe line.
• Leg yield (“side pass”) and other lateral work are difficult in one direction and easy in the other.
• When approaching a jump, the horse drifts toward one side of the obstacle.
• A barrel racer crashes into the first barrel or runs past it.
• Preference for the rider to post to one diagonal, especially in long- distance/enduro context; horse “bumps” or “shifts” rider onto preferred diagonal.
• A three-gaited horse lifts its knee and hock higher on one side than the other.
• When reining back, hindquarters go off to one side.
• Difficulty picking up one lead.
• When the horse learns to carry itself and its rider anatomically straight, all of these difficulties tend to “magically” diminish or disappear altogether.
• One forehoof points forward, the other toes out.
• One hind hoof toes outward a small amount, the other a great amount.
• All hooves break over to the same side, i.e. breakover is shifted toward one side.
• The horse develops wall flares to the same side on all four feet.
• The bulbs of the heel are not at the same height on the forefeet; the same heel bulb is higher on both forefeet; the tendency for sheared heels.
• Fore and hind hooves on one side are larger and flatter than those on the other side.
• Fore and hind hooves on one side are steeper at the toe than those on the other side.

The above items specifically relate to effects on hoof breakover and form. When the horse learns to travel anatomically straight, they diminish but usually do not disappear immediately because the hoof must re-grow. This will be our topic in the next installment when we take a close look at hoof growth, form and breakover in horses that habitually travel crookedly. 

Footnotes

1. “Overstraight” conformation of the forelimb and carpus and the underlying anatomical reasons for it are illustrated and discussed in Vol. III of my “Horse Conformation: Principles of Form and Function,” pp. 192-193.
2. The sharp reader noticed that my horse Oliver was moving at a working pace, whereas my student’s horse was trotting. He was a registered Rocky Mountain Horse (Morgan and Saddlebred bloodlines) who never trotted under saddle and a remarkably supple ride.
3. “Dynamically level” is the term used for levelness in motion; it means “average levelness.” At all gaits, the horse’s back swings from side to side depending upon which hind leg or legs it is standing on, convex side higher, concave side lower. In a horse that moves straight, the height of the two sides averages out (dynamically level); in one that moves crookedly, the concave side is on average lower (dynamically unlevel).
4. See Bennett, Deb, 2016. Longeing: Why and How. Eclectic Horseman 91:5-13. This article is available as a free downloadable .pdf by going to equinestudies.org and clicking on “Knowledge Base.”
5. To an experienced rider, many horses that travel crooked will feel “off,” but no lesion can be found even after a thorough investigation, which commonly leaves everybody scratching their heads. This relates to the significant difference between “lameness” and “lesion,” to be discussed in our next installment.