Laminitis in the horse can be a devastating condition, often instigated by a variety of circumstances or conditions. In many cases, there is no rhyme or reason to why the condition develops, or so it seems, and despite current therapies, problems persist from year to year. Although laminitis is a complex pathological process in the horse, creating much frustration for both owner and veterinarian, there are promising avenues that can greatly assist in management. Through a better understanding of the process, improved outcomes can be created with longer lasting effects for the horse.
Laminitis is often seen as a entity or problem in and of itself. Although this is true to a certain extent, I don’t believe it to be the case. I like to relate laminitis to a building that may be crumbling and falling down over time, potentially leaning to one side or another. As a building owner, you may one day see that building shifting or leaning, which can create a state of anxiety and panic. You see the immediate problem, which is the leaning, but in reality the problem has existed well before you recognized it visually. If you step back and look at the big picture, you begin to realize that the shifting of the building is due to other factors that may have been building up for years. Those may be rust in the beams supporting the building, a loosening of the foundation, water leakage, mold accumulation, or even a shifting of the ground underneath the structure. The leaning of the building is really the end result of the deterioration of the infrastructure. You can upright the building potentially, but unless the internal structure is repaired, the efforts will fail.
This is not too dissimilar to laminitis in the horse. Laminitis is a culmination of events in the horse and is a true sign of poor health on various levels, deterioration from the inside out. The immediate or acute problem that you see is the rotation of the coffin bone and pain, but really this is the end result of a weakening or breakdown of the infrastructure of the horse. Essentially, there is a much bigger problem at hand, despite seeing just the obvious. Just like with the building, if you focus all of your efforts, time, and money on correcting the leaning or rotation of the bone, the end result or outcome is minimal. You keep chasing your tail because no matter how much you correct the lean or rotation, the internal damage is ongoing.
If you want to truly correct the problem, efforts are made to stabilize and correct the coffin bone rotation, but at the same time strides are made to correct the underlying internal problems.
What is the “Internal Problem” in the Laminitic Horse?
The bottom line problem in the laminitic horse is cellular dysfunction, which means that various cells are not performing their duties properly. These may be cells associated with metabolism, thyroid function, insulin secretion and function, circulation, digestive function, hoof growth, and a variety of other vital functions. It is not just one cell type, such as the hoof tissue, but usually multiple. Thus, in the typical chronic metabolic horse, you see not just evident coffin bone rotation and pain, but also metabolism problems, thyroid dysfunction, insulin resistance, and other concerns. Multiple organ systems and cellular pathways are impacted. It’s not just the feet.
Research indicates that cellular dysfunction is at the root of many health problems not just in horses, but in people. So, why don’t these cells function correctly? Inflammation, that is the reason. Inflammation is a broad, complex cellular process that can impact cell function, through DNA activation and also mitochondrial function. This is a very deep reaching process and goes much further than just associating pain with inflammation. Pain is just one outcome to inflammation. Cell dysfunction and tissue damage is the other.
Stating and proving that inflammation is at the root of the laminitic condition is relatively easy to do, but solving that problem proves to be another problem in an of itself. Why? Mainly due to the reason that there are many contributors to the inflammatory process and these contributors will vary from one horse to the next. This is partially why no single regimen provides benefits for every horse and why in most cases, better management is gained through a personalized type of approach. This is also why no single cure will ever be developed for this disease condition. Despite this, if you can ‘see’ the bigger picture, then in most cases you can really analyze your horse’s situation and make better decisions regarding care. This can help immensely in creating a better outcome. If an owner is actively aware and involved, it is far better than just relying on another to solve the problem. The reason being is that in many cases, there is something being done in regards to supplementation, medications, diet, and even exercise that may be creating resistance to recovery. The more involved you become, the more you can see these factors, eliminate them or modify them and enhance recovery.
Factors Involved with Inflammation and Laminitis in the Horse
The process of inflammation is tightly connected with laminitis in the horse. This is well known, but where does it come from? What starts it? The answers to this are as numerous as the horses that develop the condition.
You have to step back and look at laminitic patients. They fall into one of two categories; acute or chronic. A laminitic horse that is acute is one that often is directly associated with another event such as a grain overload, endometrial infection post-foaling, endotoxemia, or contralateral lameness condition. These horses are in severe pain, have moderate to minimal rotation, but are very difficult to stabilize, deteriorating rather quickly and ending in euthanasia in many cases. In the acute laminitic horse, those primary events triggered the inflammatory response in the patient either on a direct or gut level.
A horse with chronic laminitis is much different. These horses are often overweight to varying degrees, more sedentary in their exercise patterns, lazy in their habits, low metabolism, and often exhibit varying levels of foot pain throughout the year. Their conditions tend to wax and wane, good one day, bad the other, but persist for many years. These patients are really comparable to type II diabetics in human medicine with a metabolic syndrome type of classification. If they haven’t been diagnosed as ‘metabolic patients’ with insulin function, given them some time and it will change. This is due to the progressive nature of the condition and inflammatory damage on a cellular level. The chronic laminitic equine patient is like a smoldering pile of inflammatory embers, igniting at times and creating marked damage, while at others, more controlled.
Inflammation really stems from a few factors:
- Dietary factors
- Ongoing inflammatory problems
- Gastrointestinal dysfunction
- Genetic influences
Although these factors seem to be separate, they are really connected with one contributing to another. For example, if a horse has underlying digestive issues, then the food they consume may not digest properly and thus low levels of nutrients may be absorbed impacting cell protection and tissue health. If a horse has an ongoing joint or tendon concern with high levels of inflammation, then this by itself can contribute to more inflammation through the stress pathways in the patient. Stall confinement associated with an injury recovery or as just part of the normal routine can also contribute to more stress, which gets the cycle going again. The act of putting a horse with metabolic problems on a dry lot will also greatly contribute to more internal stress and inflammation, which can also add to the digestive concerns. As an owner, you make changes to accommodate your laminitic patient with all good intentions, but some efforts may work against the end goal. The cycle repeats and compounds.
The impact of the microbiome and digestion is a huge player in the development of equine laminitis and an area of heavy research by myself for the past several years. A high percentage of these laminitic patients demonstrate a dysbiosis or shift in the normal population of bacteria in the hindgut. This then greatly contributes to the inflammatory process in the patient. I have discussed the microbiome concerns in another article.
Although I have been studying this phenomenon for years, and have arrived at solutions for many patients, it is readily clear that yet again, there are many factors involved. This can be seen in the chart below.
The Bottom Line In Equine Laminitis
In many cases, the average reader will often be more frustrated after reading this information than what they were originally. This is not and was not my intention when creating this article. My hope was to relay a better understanding of the problem at hand, realizing hopefully that the concerns in the foot regarding rotation and pain are really an effect, rather than the cause. The rotation of the coffin bone and subsequent pain are an end result, not the primary problem.
Does this mean that we just ignore the feet? No. Again, this is analogous to the leaning building. You have to make every effort to realign the external structures, but even more important is to recognize and manage the internal ones. Keep in mind here that I said, “realign the structures”, which implies that proper trimming is done to physically re-establish balance to the foot and with that, realignment of the internal structures over time. This is much different than just relying on various shoes to provide support or redistribute weight.
So many owners that I have interacted with as a veterinarian and consultant have mainly focused on the feet in various ways, while then attempting to remedy the internal problems via a low starch feed, reduced quality hay, and no pasture turnout. Supplements are used but are often misguided, thinking that one nutrient or one herb may be the solution. Then on top of this, often there are medications not just to aid in management of pain, but to control other secondary processes including blood sugar management and insulin function. In some patients, there are even medications to support pituitary function, as in the case of a PPID patient. These approaches are helpful in some patients, but technically speaking, they are band-aids at best, meaning to control other disturbed cellular process impacted by inflammation. A high percentage of these laminitic patients are still experiencing recurrent flare-ups year after year, despite their supplementation or medication regimens. This should tell you that there is more to the story that is possibly overlooked.
If you can properly control the inflammatory response, which can involve several different approaches, then the cellular function is often readily improved on all levels. Pain is improved, but so is metabolism, thyroid function, insulin receptivity, tissue health, hoof growth, and circulation. Cellular function is improved, normal functions in the body are restored and with that, health is dramatically enhanced!
How do you do this?
The Type II Diabetic as a Guide for Laminitic Management
A type II human diabetic is not too far removed from equine laminitis in my opinion, especially the chronic laminitic patient. In both examples you have an overweight patient in most cases. The overweight body condition by itself has been known to precipitate a higher level of inflammation in that patient. This is then compounded by a poor overall diet lacking in proper nutrients and a lower level of exercise, which further fuels the inflammation. Interestingly enough, both groups also have a demonstrated dysbiosis or negative shift in the populations of bacteria in the digestive tract. Just like laminitic patients, human diabetic also have dysregulated blood sugar, insulin function, and altered nerve function and circulation. Humans don’t experience coffin bone rotation, but do experience circulatory issues in the lower extremities which is very comparable and life altering. All of these health conditions or developments are a result of the progressive inflammatory damage on a cellular level, getting worse over time.
So…the two are not too dissimilar.
If you then look at human research, one avenue that provides moderate improvement in patients is through modification of diet and lifestyle factors. Instead of processed foods, patients readily improve via a whole-food, plant based diet. They also respond readily to various herbs, often in combination, taken as a supplement or used as a part of their cooking practices. Exercise then becomes a big factor in these patients, improving metabolism, weight, blood sugar, inflammation, and overall mental outlook. Through these approaches, when fully applied, human patients can do quite well with significant control of their medical condition without the need for medications. In fact, most actually do better on this regimen than they did on numerous medications each day. All of these efforts by the patient modify the inflammatory status within their body. Reduce or better manage that inflammation and cellular function can be restored and with that healing is enhanced.
This is the approach that we need to be taking in the equine laminitic patient, seeing the bigger picture and taking into consideration all factors involved. Through this approach, the process of inflammation is more readily managed on a higher level, impacting cell function throughout the body. In many cases, due to a change in the diet, the microbiome within the gastrointestinal tract rebalances on its own, which then impacts inflammation additionally. This shift in the microbiome can come directly as a result of the foods consumed, via prebiotic effect or phytochemical influence, or the positive shift can come about due to reduced stress on the body through other avenues pursued by the patient.
How do we do this in the equine laminitic patient? That is for part two of this article, relaying our current and future approaches that we use in patients every day.
Author: Tom Schell, D.V.M., CVCH, CHN