All Seasons Veterinary Practice LLC

23/02/2026

Yes

You don't need to grow up on the back of a horse to be a changemaker in equine medicine. Dr. Marquis Harper proves that a profound calling can find you at any career stage. This Black History Month, the AAEP is honored to celebrate Dr. Harper’s commitment to excellence in clinical care and his work in opening doors for future horse doctors.

An associate ambulatory veterinarian with Erskine & Associates Equine Veterinary Practice in Mount Airy, Md., Dr. Harper initially focused on livestock medicine at Virginia-Maryland College of Veterinary Medicine His deep appreciation for working with equids began as a third-year student and took off during his rotating large animal internship at the University of Tennessee—particularly while managing cases in the ICU.

“As a clinical student, I completed several externships that were primarily livestock-focused but also ‘saw horses.’ I began to notice that the standard of care for the equine patients was limited. That realization motivated me to strengthen my equine knowledge and be able to provide a higher level of care across all large animal species.”

Dr. Harper also greatly values the opportunity to educate students who ride along with him and to demonstrate that this career path is not only possible, but attainable.

“One piece of advice I give to future equine and large animal veterinarians is this: it is absolutely something we can do—and we can do it well.

“In my veterinary class, VERY FEW students from underrepresented groups were tracking large animal medicine. But veterinary medicine is evolving. It is becoming more diverse—gradually, but meaningfully. When I began my training, I rarely saw veterinarians who looked like me. Today, I can say I have met and been mentored by veterinarians of color and other underrepresented professionals who are surgeons, specialists, and leaders in this field. That visibility matters.

“Don’t be discouraged by the rooms you walk into. Walk in fully as yourself and give your best—every time.”

16/02/2026

A straight horse. Harder than you might think. I like the math included in this.

In his book The One Thing, Gary Keller poses a question that has stayed with me for years: What’s the ONE thing you can do such that by doing it everything else will be easier or unnecessary? I find myself returning to that question often in my work with horses. When we strip away trends, gadgets, and discipline-specific goals, what is the foundational quality that organizes everything else?

For me, the answer has increasingly become straightness.

Every horse is naturally crooked. I don’t say that critically—it’s simply biology. One hind limb tends to assume a greater weight-bearing role, while the opposite hind contributes more to propulsion. The shoulders rarely align perfectly in front of the haunches. The ribcage tends to drift. At lower intensities, these asymmetries can feel manageable, even subtle. But crookedness is not just a visual trait; it is a pattern of force distribution. And as the demands we place on the horse increase, so do the consequences of that pattern.

Straightness, biomechanically defined, is the symmetrical organization of force. In a straight horse, the hind feet track into the forefeet, the spine aligns with the line of travel, and propulsion generated in the hip, stifle, and hock travels forward through the sacroiliac joint and lumbosacral junction into a balanced thoracic sling. Each diagonal pair shares cyclical loading. The trunk oscillates evenly. The center of mass stays organized between the limbs.

Crookedness changes the direction of force.

When one hind limb dominates, its propulsive effort is not directed purely forward but slightly medially or laterally. Any force vector can be divided into components. Ideally, most of that vector contributes to forward motion. In a crooked horse, part of it becomes lateral—wasted energy that creates torque around the spine.

Torque (τ = rF) increases as either force (F) increases or as the distance from the axis of rotation (r) increases. As we ask for more impulsion, more collection, or more speed, ground reaction forces rise. Kinetic energy scales with the square of velocity (KE = ½mv²). Doubling speed quadruples energy. So as intensity increases, asymmetry is magnified—not linearly, but exponentially.

At moderate workloads, crookedness may show up as uneven contact, difficulty bending one direction, or unilateral muscle development. But as forces rise, the mechanical consequences escalate:

Uneven compression of articular cartilage

Asymmetric strain on suspensory ligaments and tendons

Repetitive shear forces in fetlock and coffin joints

Chronic torsional stress through the sacroiliac region

Bone remodels along lines of stress. Tendons adapt to consistent strain. But they adapt to how they are loaded. When loading is asymmetrical, adaptation becomes asymmetrical. Over time, microdamage accumulates.

Nowhere is this more unforgiving than in the Thoroughbred racehorse.

At racing speed—15–18 meters per second (34–40 mph)—ground reaction forces during gallop can exceed 2–2.5 times body weight per limb per stride. In a 500 kg horse, that is over 1,000 kg of force transmitted through a single limb in under 120 milliseconds of stance phase. There is no time for correction mid-stride. Whatever alignment exists at push-off is amplified by momentum (p = mv) and must be redirected every stride.

If propulsion from behind is misaligned, the forward component of the force vector decreases while the lateral component increases. The horse recruits additional stabilizing musculature—longissimus dorsi, obliques, thoracic sling—to counter-rotate and prevent drift. Metabolic cost rises. Stride efficiency falls. Energy that could extend stride length instead stabilizes imbalance.

On straightaways, this may look like lugging in or bearing out. Internally, it is rotational torque. One forelimb—often opposite the dominant hind—absorbs greater compressive and shear forces. Repetitive asymmetric loading increases risk of suspensory injury, condylar stress fractures, and distal limb pathology.

On turns, centripetal force (Fc = mv²/r) increases with the square of velocity. If the horse already carries uneven weight behind, entering a bend compounds the imbalance. The inside limbs experience greater compressive and shear stress while simultaneously managing rotational torque from crooked propulsion. The structures most vulnerable are the ones already overloaded.

The faster the horse travels, the more the square-law relationship between velocity and force punishes asymmetry.

So when I come back to Keller’s question—What’s the ONE thing you can do such that by doing it everything else will be easier or unnecessary?—I keep landing in the same place. Straighten the horse. Align the force. Organize the body before asking for more.

How I systematically pursue that straightness—how I address neuromuscular dominance rather than simply managing symptoms—is something I’ll share in my next post. Because the method matters.

**Notice the compensatory posture assumed by the not-so-straight horse below...that right front doing much more than it's fair share to keep the horse traveling forward. It's my husband in the irons for another trainer, barely keeping it between the ditches!

16/02/2026

Interesting. Thoughts?

The Frog Test: A Case Study Every Horse Owner Should See:-

When evaluating a hoof, most eyes go straight to the wall.

Cracks. Chips. Flares. Growth rings.

But what if the real story is hiding in the center?

This case study proves one powerful truth: The frog never lies.

The First Impression:-

At first glance, this hoof didn’t scream emergency. The wall had some distortion. The heels looked slightly contracted. Nothing dramatic enough to cause panic.

But when we looked at the frog — everything changed.

The frog appeared narrow, elongated, and deeply cleft through the central sulcus. Instead of being wide and ground-engaging, it was recessed and tight. The central sulcus was deep enough to trap debris and moisture.

That was our first red flag.

Why the Frog Matters:-

The frog is not just a “soft triangle.” It plays a critical role in:

1) Shock absorption
2) Blood circulation within the hoof
3) Heel expansion
4) Load distribution
5) Proprioception (the horse’s sense of ground)

A healthy frog should be:

1.Wide and full
2.Slightly callused
3.Sharing load with the heels
4.Free of deep central cracks

When the frog becomes narrow and deeply split, it often indicates:

1) Contracted heels
2) Caudal hoof weakness
3) Lack of frog engagement
4) Possible thrush in the central sulcus
5) Chronic imbalance

And that’s exactly what this hoof was showing.

The Hidden Problem

Here’s where it gets interesting.

The wall distortion was actually a symptom — not the root cause.

The deep central sulcus suggested long-term heel contraction. When heels contract, the frog loses proper ground contact. When frog engagement decreases, circulation and digital cushion stimulation decline.

Over time, this can lead to:

1.Poor shock absorption
2.Increased strain on the deep digital flexor tendon
3.Compensatory loading at the toe
4.Eventual lameness risk

The frog was telling us this hoof wasn’t functioning efficiently from the back half.

And most owners would have missed it.

The Solution Strategy:-

Instead of just trimming the wall and making it “look neat,” the approach focused on restoring function:

1)Address heel balance carefully -not aggressively lowering them.
2) Open and clean the central sulcus to eliminate bacterial environment.
3) Encourage frog engagement with proper trim mechanics.
4) Improve environmental management (dry footing, hygiene).
5) Monitor over multiple cycles — because heel rehab takes time.

The goal was not cosmetic correction.

The goal was functional restoration.

Within trim cycles, the frog began widening. The central sulcus became shallower. Heel expansion improved. The hoof started loading more evenly.

That’s the power of reading the frog correctly.

The Takeaway for Horse Owners:-

If you only look at the hoof wall, you’re seeing the surface.

If you look at the frog, you’re seeing the truth.

Next time you pick up your horse’s foot, ask yourself:

1.Is the frog wide and healthy?
2.Is the central sulcus shallow or deep?
3.Are the heels supporting it properly?

Because small frog changes today can prevent major lameness tomorrow.

👉 Want to learn how to read your horse’s frog like a professional?

Follow for more real case studies that break down hoof science in simple, practical terms and help you protect your horse before problems become expensive emergencies.

12/02/2026

Fun facts

Everybody knows about diagonals, right? However, not long ago I was talking with a riding instructor who had shown a fair amount including as a member of a college equestrian team. The subject of diagonals came up, and I could tell she didn't understand why we rise when posting the trot in a bend on the forward reach of the outside diagonal.

I explained why and her response was that no one had ever taught her. Now she is teaching diagonals to the next generation without giving a reason why we rise on the outside diagonal except that it's what judges want.

The reason why we rise on the outside diagonal is based in the fact that in a bend the inside diagonal is shorter than the outside diagonal. In the image below the right diagonal is shown as being shorter than the left diagonal. We want to rise on the outside diagonal to free up the horse's outside reach that is longer than the inside reach that is somewhat "compressed" in the bend.

Additionally, by rising on the outside diagonal, when we straighten our knees, our body moves somewhat forward as well as upward. This lightens and evens the stride as a result of our body mass being slightly forward. When we sit the trot with a trained horse the push is more from their hind than any pull forward with their shoulders. Therefore, when we post the push from the hind becomes less intense and freer.

Lastly, there is another reason for posting on one diagonal instead of the other, and it is when the horse is going straight at the trot and when the diagonals are of equal length. Can you guess why?

The lengths of US Cavalry mounted marches were limited by regulations. A standard distance was 25 miles per day and for a forced march the limit was 75 miles. If the Cavalry Troopers posted always on one diagonal, their horses would develop their muscles unevenly. To prevent this the Troop was required to periodically change diagonals all together on command. The Troop leader would count off a number of strides, I have read 50, and then tell the troop to change. I know very little about endurance riding, but I suspect that they follow this same principle as the Army did.

If you like this kind of nerdy explanation posts, I wrote another last week you might have missed. Don't forget to follow the page and like the posts.www.facebook.com/BobWoodHorsesForLife/posts/pfbid049L8fNorrToUtnH3RUXCCi1YxnF7EvaB1nVuy3gzRCcF7KLMdork4sNooTxbYe2hl

28/01/2026

Interesting read for the Quarter Horse fans out there

This is RP Recoil N Strike, aka “Striker.”

Striker is by Coil, a Thoroughbred stallion that won four graded stakes races and earned over $1.1 million on the track. Striker is out of Dashin Julene, a very accomplished daughter of Dash Ta Fame.

Although Striker has a Thoroughbred sire and a Quarter Horse dam, he is not an “Appendix.” There are two main reasons for that:

1. The Appendix is a sub-registry of the American Quarter Horse Association, not a type of horse.

2. In 2022, Striker was the AQHA Reserve World Champion Junior Barrel Racing Horse. He earned a Register of Merit and moved to the Numbered registry.

The following is a history of the Appendix and an explanation of how it works.

Today, the AQHA issues certificates to horses in the Numbered or Appendix registries, depending upon the registration status of their sires and dams. Prior to 1962, horses registered with the AQHA were issued certificates with one of three labels - Permanent, Tentative or Appendix.

Like the appendix of a textbook, the Appendix of the AQHA came after the main stud book and essentially provided supporting documentation. Horses that did not meet the requirements for registration were included in the Appendix section for identification purposes, but were not technically registered with the AQHA. This group included horses that were previously registered with the American Quarter Racing Association and the National Quarter Horse Breeders Association, organizations that merged with the AQHA early in the association’s history. The Appendix also included outcrosses to horses registered with The Jockey Club - Thoroughbreds.

The AQHA used to have inspections similar to inspections performed by Warmblood registries today. When horses in the Appendix passed inspection for conformation, they would receive Tentative registration. Horses in the Appendix could bypass inspection by exhibiting superior performance on the racetrack or in the arena. If they earned a Register of Merit or ROM, they would receive Tentative registration without inspection. Horses with Tentative registration could only receive their Permanent papers when enough of their offspring received Tentative status.

By 1954, the number of horses in the Appendix exceeded the number of horses with Tentative and Permanent certificates combined. The system was overly complicated and confusing to owners. These factors prompted reform.

At first, the AQHA proposed closing the stud book, which would have made it impossible for Thoroughbred outcrosses to be registered with the association. Racing and performance horse breeders opposed this idea. They cited the contributions that Thoroughbred stallions such as Three Bars made to the Quarter Horse breed.

Ultimately, the AQHA decided to combine the Tentative and Permanent registries. This became the Numbered registry. They also established a new Appendix. The horses in the new Appendix are registered with the association, but their registration numbers begin with an “X” and their papers say “APPENDIX CERTIFICATE” at the top.

Once this new system was in place, foals with two Numbered parents automatically received a registration number without inspection. Horses received Appendix certificates if they had one Appendix parent and one Numbered parent or one Thoroughbred parent and one Numbered parent. It is important to note that horses with two Appendix parents or one Appendix parent and one Thoroughbred parent are not eligible for registration with the AQHA. There are smaller registries that accept those horses.

The new Appendix is similar to the old in that horses with Appendix certificates can obtain a Numbered certificate by earning a ROM in AQHA-approved events. Horses having parrot mouths, cyptorchidism, HYPP or excessive white markings are not eligible for advancement into the Numbered registry.

When a horse in the Appendix attains a Numbered certificate, the breeding restrictions, along with the “X” in front of their registration number, are removed. Any of the horse’s offspring that were listed in the Appendix become eligible for advancement into the Numbered registry as well. This means that horses with very little Thoroughbred parentage may have Appendix certificates their entire lives. It also means that horses with very little Quarter Horse parentage can earn Numbered certificates. It is possible to see horses that are 7/8ths Thoroughbred with Numbered certificates. Horses such as The Signature and Some Kind of Man are examples of that.

Although the system for Appendix registry and advancement has been simplified, many people still find it confusing. It is a common misconception that horses with Appendix certificates from the AQHA are not Quarter Horses, but they are!

The AQHA allows Thoroughbred outcrosses in the first place because many of the original “Quarter Horses” were simply Thoroughbreds that could run short. Thoroughbreds have always been critical to the development and improvement of the Quarter Horse as a breed.

Striker will undoubtedly continue that legacy of improvement. We couldn’t find a fault in him if we tried!

Striker is owned by Rachel and Roger Primm. He is standing at Switzer-Hill Horses in Weatherford, Texas.

07/01/2026

Has been really tricky to manage sometimes but there are things to try.

26/12/2025

Some very good points here.

"When I first got out of veterinary school and started looking at horses prior to purchase (usually referred to as a “vet check” or a prepurchase exam), the horses usually fit into one of three categories.

The first category was the horse with no problems noted at the time of the exam. That decision was usually pretty straight-forward. I’d look at the horse and if I didn’t find or see any problems, that was usually that.

The second category was for a horse that wasn’t sound at the time of examination. I wasn’t always sure WHY the horse was limping – determining why a horse was limping is a lameness exam, not a presale exam. If the horse was limping noticeably, usually that was enough, and particularly if I could find the reason why (say, an arthritic joint).

The third category was what used to be referred to as, “Serviceably sound.” That is, the horse may not have been perfect, he might have been a little stiff going in one direct, but he had been doing his job for a long time and, in my opinion, he could probably keep doing the job that was asked of him for a good while longer. But today, in this day of X-raying every bone, pushing, prodding, flexing, and making SWAGs (SWAG = Scientific Wild-A** Guess) about the future, I’m often left wondering, “What happened to that horse that was serviceably sound?”

About two years ago I was asked to give a fourth opinion on a 20-year-old warmblood horse. The horse had been through the entire diagnostic gamut: MRI’s and bone scans, ultrasound and X-rays of most every bone in the horse’s body. She’d had expert opinions from hospitals and radiologists. She wasn’t moving 100% sound and all of the diagnostic tests and all of the expert opinions confirmed that the horse should never be ridden again (I know because I saw the reports).

As you might imagine, I wasn’t immediately sure what I could bring to the table, what with all of the diagnosing and opining that had already gone on. Nevertheless, I ran ma hands over her legs, felt the slight swelling in her stifle joints, and I noticed the stiffness when I flexed her legs. This sweet, patient mare never objected to anything that I did and never fought back against anything I asked. Next, I asked to watch her move. She certainly didn’t have a full, easy moving gait but she moved willingly: happily. So I asked, “What do you want to do with her?”

The owner, who obviously cared about her horse enough to float the budget of a few small countries, said, “I’d like her to be able to give lessons to kids.”

“Why don’t you give it a try?” I said.

The owner, furrowing her brow, responded, “But what about all of the reports?”

I said, “Don’t let her read them.”

Today, three years later, the old girl regularly and happily gives lessons to kids in a riding program. She doesn’t go very fast or for very long, and it helps her to get a pain-relieving drug from time to time. But she’s got a job, she’s the apple of the eyes of any number of kids, and she’s, well, happy (at least as far as anyone can tell).

ANOTHER ASIDE: A saw a 18-year-old gelding who had been through MRI and blocking and X-rays and medication and shoeing changes as a result of a hoof problem that just wouldn’t let the horse move without a slight forelimb limp, especially when the horse had to go in a circle. I travelled a good bit out of my practice area, looked at all of the data, and asked the owner, “What do you do with him?”

The owner said, “I take him out for walks on the trail two or three times a week.”

And I said, “Why not just give him a little bit of pain reliever when you go out on the trail and let him walk around this nice arena the rest of the time?”

“But won’t the pain reliever destroy his stomach?” she asked.

“No.”

That was four years ago. I saw the owners at a lecture I gave a year or so later and everyone was happy. As far as I know, his stomach didn’t explode, and things are still going well. It’s a good situation for everyone.

The reason that I bring this up is that to me, it seems that the business side of the horse world is suggesting that the only thing a horse owner should be satisfied with is perfect or “optimum” or “ideal” or some other bit of linguistic innuendo that suggests that a horse just might have some hidden problem lurking beneath his skin that’s going to result in imminent death or disaster. It seems to me that the business world is trying to sell horse owners on the idea that there are only two choices for a horse: perfect or disaster.

I think that the relentless search for perfection in horse health is mostly terrible. I think that constantly worrying about horses, spending hours on the internet looking for information about what might go wrong helps deprive a lot of horse owners of the joy of horse ownership. If your horse looks at his side, it usually doesn’t mean that he’s twisted his intestines. If your horse is on a good diet, it’s extremely unlikely that he’s on the edge of some nutritional cliff, about to fall over but for the good fortune that you’ve had in finding the latest supplement. Worrying about your horse too much can lead owners to seek out unnecessary testing, to waste money on veterinary (and other) visits, and to look for comfort from endless interventions and products.

Of course, it’s good to be aware of your horse’s health. But there’s a difference between being worried about your horse when he’s sick or limping and being constantly worried about him becoming sick or lame. Excessive worrying about a normal horse is a real problem: mostly, for the horse owner.

YET ANOTHER ASIDE: A 70-year-old client came to me with her 19-year-old gelding. She’d been given the horse from a riding school and she was concerned because she had been told that the horse was limping. I watched him trot – there was a slight limp.

“What do you do with him?” I asked.

“I like to walk on the trails with him on the weekend with my friends. Or maybe every other weekend.”

I could feel a slight enlargement at his pastern – I was pretty sure he had a bit of osteoarthritis (also known as “ringbone”).

Here’s a partial list of things that I did not recommend: X-rays, bone scan, MRI, joint injections, joint supplements, special shoes, liniment, PRP, or stem cells.

Instead, I pointed to her husband, 75, and said, “How’s Fred? Is he getting around the same way he did when you were married 50 years ago?”

Laughing, she said, “No.”

“Want to get rid of him?”

“Only sometimes” she smiled.

I told her to keeping going on nice long walks, and perhaps give him (the horse – I don’t prescribe medicine for people) a pain reliever if he’s limping a bit. Things have been going great for several months – in fact, I saw them both just the other day. It’s a perfect situation for both of them. Nobody is perfectly sound, including Fred. But everybody is serviceable. And happy.

So what’s “serviceable?” I think that it means that the horse can do the job that’s being asked of him without suffering. Horses will generally go out and try to do their best – that’s one of the things we love about them. It’s our job to take care of them, but it’s not our job to make everything perfect: that’s an impossibility. A horse can be less than perfect and still be wonderful.

Here’s Mark Twain’s idea of a good horse. “I preferred a safe horse to a fast one—I would like to have an excessively gentle horse—a horse with no spirit whatever—a lame one, if he had such a thing.” (Roughing It, Chapter 64).

I don’t usually see things as black and white. I tend to think that the perfect is the enemy of the good. I don’t think that a horse is either good or bad. There are lots of good horses out there that might have a little flaw or imperfection but who will also be the best horse anyone could ever ask for. Don’t overlook one of them simply because he’s not somebody else’s idea of perfection. He might not be perfect, but he can still be serviceable… and even still be great!"

📎 Save & share this article by David Ramey, DVM at https://www.theplaidhorse.com/2021/08/09/what-ever-happened-to-serviceably-sound/
📸 © The Plaid Horse

23/12/2025

Good advice!

If you own horses long enough, sooner or later you are likely to be confronted with a medical emergency (even during the holidays). Are you prepared?

Having a clear emergency action plan will help you stay focused and effective if a crisis strikes. Below are some basic guidelines that can help you prepare for an equine emergency:

1. Know how to reach your regular veterinarian after hours. Ask about a back-up or referring veterinarian in case your regular horse doctor is not available for emergencies.

2. Have a plan for transporting the horse if necessary and know in advance the most direct route to an equine surgery center.

3. Prepare a first aid kit and store it in a clean, dry, readily accessible place. Keep a first aid kit in your horse trailer or towing vehicle as well and be sure to check your supplies periodically and restock as needed. First-aid kits can be as simple or elaborate as you’d like; seek your horse doctor's advice on what to add, especially regarding any drugs that could be included and how they should be administered.

20/12/2025

Interesting read from both a veterinary professional and rider point of view. Especially about steering the shoulder to change trajectory. As a rider- so interesting to know why

The Thoracic Sling: The Horse’s Primary System for Balance, Posture, and Force Organization

For generations, equestrian tradition taught that the hindquarters were the horse’s primary source of power. Riders were encouraged to “ride from behind,” develop engagement, and focus training almost exclusively on the rear of the horse. While the hind end is indeed responsible for propulsion, this view does not fully explain balance, posture, straightness, elevation, or whole-body coordination.

Modern biomechanics presents a more complete picture. The hindquarters generate thrust, but the thoracic sling organizes, stabilizes, and directs the horse’s movement. The forehand—specifically the thoracic sling and its integration with the core—the primary system for organizing balance and posture in motion.

The Traditional View Was Hind-End Dominant

Classical training emphasized the hindquarters as the horse’s engine. This is accurate in terms of generating forward thrust, contributing to carrying power, adding part of the horse’s ability to collect, and sharing load with the forehand.

However, the hind end does not independently determine where the body mass travels, the height of the trunk, the organization of the spine and ribcage, straightness or lateral balance, or the ability to elevate the forehand.

The hindquarters push, but they do not control the system they are pushing into.

The Thoracic Sling Is the Horse’s Primary Balancing and Postural Engine

The thoracic sling is a muscular-fascial suspension system that holds the trunk between the forelimbs. Functioning in place of a clavicle, it does far more than support the front end.

The thoracic sling suspends the ribcage between the forelimbs, regulates trunk height, absorbs landing forces, stabilizes the shoulders during movement, initiates upward shifts of the center of mass, determines how weight is distributed front to back, controls straightness and lateral balance, and integrates with the deep core to manage whole-body posture.

In biomechanical terms, the thoracic sling is the horse’s primary balancing and postural system. Without a functional sling, the hindquarters cannot translate their power through the body in a stable or organized way.

The Hind End Pushes — The Thoracic Sling Catches

This concept aligns with findings from force-plate studies, kinematic analysis, and myofascial research.

Current research shows that the forehand is responsible for most vertical control of the trunk, the thoracic sling plays a substantial role in stabilizing the ribcage, the trunk cannot elevate unless the sling and core activate first, self-carriage depends on thoracic suspension rather than hind-end drive alone, and power from behind becomes ineffective if the front cannot control incoming forces.

In motion, the forelimbs do not simply carry weight. They manage balance, braking, and impact absorption. The thoracic sling processes these forces and determines how effectively they are redistributed through the body.

The Modern Shift Across Disciplines

This updated understanding influences every area of equine performance and care.

In rehabilitation and return-to-work planning, thoracic sling function is now prioritized before intensive hind-end strengthening.

In dressage and classical schooling, true self-carriage requires elevation of the withers through the sling rather than force from behind.

In jumping, a functional sling is essential for correct bascule, shoulder freedom, and safe landing mechanics.

In bodywork and movement support, thoracic sling tension and fascial organization influence cervical mobility, forelimb swing, and trunk lift.

In hoof care, the way the foot lands and loads directly affects how both the hindquarters and thoracic sling must compensate during stance and motion.

Across disciplines, the thoracic sling is increasingly recognized as central to posture, balance, and performance.

Why the “60 Percent Forehand Weight” Rule Is Misleading

The commonly cited idea that the forehand carries 60 percent of the horse’s weight applies only to a standing horse on level ground without a rider. In dynamic movement, particularly under saddle, this percentage increases.

Forehand load rises due to the horse’s naturally forward center of mass, the added weight of the rider, variations in hoof balance and trim, posture and core strength, gait mechanics, landing forces, and weakness or collapse within the thoracic sling.

During trot and canter, forelimb loading often exceeds 60 percent and may reach 65 to 75 percent or more. This increased demand makes the thoracic sling the primary structure responsible for stabilizing and supporting the trunk in motion.

Steering Comes From the Shoulders

In horses, steering does not originate in the head or the hindquarters. Direction, line, and balance are determined by the orientation and control of the shoulders, which are suspended by the thoracic sling.

The thoracic cage sits between the forelimbs as a suspended structure. Wherever that structure is directed, the rest of the body must follow. The head follows the shoulders because it is attached to the cervical spine, which is anchored to the thorax. The pelvis and hind limbs follow because they are connected to the thoracic cage through the spine and continuous fascial chains.

A horse cannot truly go straight if the thoracic cage is crooked between the forelimbs. The hindquarters may push powerfully, but they will simply propel the body along the path the shoulders have already chosen. This is why pulling the head does not create straightness, pushing the hindquarters does not correct drift, and controlling the shoulders changes the entire trajectory of the horse.

When the thoracic sling is balanced and functional, the shoulders set the line and the rest of the body organizes naturally behind it.

Thoracic Cage Balance Determines Hind-End Function

The balance and alignment of the thoracic cage directly determine how effectively the hindquarters can work.

If the thoracic cage is dropped on one side, rotated between the forelimbs, collapsed through the sling, or unstable in vertical suspension, the hindquarters are forced into compensatory strategies rather than true engagement.

This often presents as asymmetrical stepping, uneven push mistaken for strength differences, difficulty bending evenly left versus right, loss of straightness despite strong hind-end effort, and increased strain through the lumbar spine and sacroiliac region.

The hindquarters do not choose these patterns. They respond to the balance problem they are pushing into.

When the thoracic sling lifts, centers, and stabilizes the ribcage, both hind limbs can step under evenly, propulsion becomes directed rather than wasted, carrying power improves without force, and collection becomes easier rather than more demanding.

Hind-end quality, therefore, reflects thoracic organization rather than the other way around.

A More Accurate Model of Equine Power

A modern, biomechanically accurate model is emerging.

The hindquarters generate propulsion.
The thoracic sling organizes the body, stabilizes the trunk, and distributes forces.
The core integrates the two into a coordinated whole.

This framework explains why straightness cannot be achieved through hind-end work alone, why self-carriage depends on wither elevation, why forehand heaviness is rarely a hind-end problem, and why movement quality arises from postural control rather than raw power.

Power without organization creates imbalance which crrates tension. Balance allows power to express itself. The future of equine performance lies in organizing the power the horse already has.

https://koperequine.com/the-thoracic-sling-axial-skeleton-interplay/