Laminitis is a devastating condition in the equine industry, impacting every breed and gender. No one horse is immune to the condition, but it appears that certain groups of horses are more prone to others. The causes of laminitis can be many and often, the underlying cause can dictate success or failure. If we take certain steps to address the problem on a broader level, then often the condition can be more readily managed for the long term.
In order to discuss laminitis and therapy options on a broader level, we must first gain a better understanding of the condition. Laminitis by definition is inflammation of the laminar tissue, which is the tissue located within the hoof capsule which binds to and secures the coffin bone. We have different levels of laminar tissue, some breaking it down into sensitive and insensitive laminae. The sensitive laminae covers the coffin bone or P3 and connects to the insensitive laminae on the inside of the hoof by means of finger like interdigitations. I would often refer to this attachment with our clients as being like a ziplock bag seal for simplistic terms. When applying a shoe to a horse, the nails are placed in the white line region, pushing towards the insensitive section. When a nail is viewed as being ‘hot’, resulting in lameness, it implies the nail was improperly placed and impinging on the more sensitive laminae.
What is Laminitis?
When we think of laminitis, most are familiar with the rotation of the coffin bone, which is a result of several factors. First, there is loss of integrity of the laminar tissue, leading to a loss of connection between the two sections and inevitably, loss of securing of the coffin bone in position. Second, the backward pull of the deep flexor tendon, which inserts on the underside of the coffin bone, combined with downward pressure on the foot, causes the coffin bone to rotate. This level of rotation is dependent on the severity of the insult and time frame involved. However, the amount of rotation does not dictate prognosis in my opinion as we can have severe rotation in chronic cases, but very little rotation in very acute and painful cases. That being said, the amount of rotation is really significant when combined with the factor of time. A large amount of rotation in a very short period of time in more critical than a large amount of rotation over months or years. Some patients have contended with laminitis flares over many years, stabilizing in between the flares. It is not uncommon to find significant rotation in those horses, but find that clinically they are often stable with little lameness. In some cases, we can have an acute laminitic situation and a very painful patient, but very little rotation on x-ray evaluation. It is the rotation and separation of the lamina that is creating pain for the patient.
The biggest focus when managing a laminitic patient is attention to the foot, which is correct, but we often forget about other players in the game and underlying contributors to the problem. If we look outside of the foot and try to correct some other factors, on a higher level, then often our success is better.
Typical Presentation of Laminitis:
A laminitic horse can present in a variety of ways, but the main clinical presentation is a horse that is reluctant to move forward and walk. When they do, they are stiff and almost have to be forced to walk as it is uncomfortable. In most situations, laminitis is impacting both front feet but it can only affect one foot and even involve the rear feet as well. In these horses, we have increased digital pulses to the feet which are readily palpable. Hoof testers are usually positive in the toe region, just in front of the apex of the frog with only light pressure applied. These horses are often reluctant to yield a foot for examination, as when they do, they are forced to bear more weight on the opposite, which increases pain. They will often also rock their weight back onto the rear limbs, which provides relief to the front feet and allows them to move in a more comfortable manner. Often, we will even find these horses recumbent or lying down, as it is a means for them to rest and take weight off of their feet. Overall, these clinical signs are fairly consistent from one horse to the next, but the rate at which the signs develop can vary, dependent on the cause. Some can seem like they develop overnight, while others are a slow progression becoming worse over a matter of days or even weeks.
Assuming that we have a proper diagnosis and that the patient is truly suffering from laminitis, we can then move into some options for therapy.
The Seven Steps in Managing a Laminitic Patient:
- Stabilize the Foot: This is one critical area that we as vets struggle with, applying all sorts of techniques. If you ask 10 vets or farriers how to stabilize the foot, you will get 10 different answers likely. There is no one correct way or method. The correct way is what works for the patient. Stabilizing the foot is critical, as it helps to relieve pain and restore comfort for the patient. Pain is a viscous cycle and recurrent pain results in higher levels of stress and can actually contribute to and propel the situation. The foot needs to be stabilized not only in the acutely painful patient but also in the chronic patient that may or may not be demonstrating clinical signs. If the coffin bone is rotated, then we need to restore alignment to the best of our abilities. In the acute stage, I personally do not worry too much about making modifications to the hoof or trimming, but more so focus on just support of the coffin bone. This could include putting the patient into deep bedding to provide support, applying styrofoam pads to the sole for comfort or application of Lilly Pads for support. If the patient has a long toe, then we will often reduce it or pull it back in order to facilitate comfort and help restore angles. Once the patient is stabilized, then more serious modifications can be made through trimming or shoe application, if desired. Personally, I have used shoes over the years but have found the best value through barefoot trimming and balancing based on x-ray findings.
- Bloodwork and Laboratory Testing: This is another critical area that needs to be performed in all laminitic patients. Often, we overlook this step in the chronic laminitic patient as focus is just paid to the feet. A complete blood count (CBC), general chemistry panel and fibrinogen should be performed in all patients as a baseline. The CBC will allow us to detect infection, stress response and anemias if present. The chemistry panel allows us to check electrolytes, organ function, protein levels and serve as indicators of dehydration along with the CBC. Fibrinogen is an acute phase protein which is often elevated in cases of inflammation and can serve as an indicator of severity and response to therapy. Serum amyloid A (SAA) is another acute phase protein that is being used more as an indicator of inflammation in some horses. In many other patients, especially chronic cases, we will expand our bloodwork further to include insulin levels, cortisol and ACTH testing. This would help us to rule in or out the involvment of metabolic problems and Cushing’s syndrome. In my experience, insulin levels can actually be reflective of acute inflammation when elevated and do not always infer metabolic problems. In some horses with acute injuries and associated inflammation, we find that the insulin is elevated but quickly returns to normal over 24-36 hours with proper management.
- Treat Concurrent Problems: What is implied here is that if we have a primary problem that can be addressed, which is contributing to the laminitis, then we should pay attention and make sure we are addressing the issue. Such would be with a mare that has a retained placenta, colic, infection, a horse with primary organ problems, grain overload, toxicity, dehydration, anemia and even Cushing’s problems. If the primary problem is not addressed, then our chances of managing the laminitis decreases.
- Manage Inflammation and Pain: This is one crucial area which is constantly discussed and reviewed with much debate in the veterinary community. One of the biggest things we can do to manage pain in the patient is to stablize the foot. In reality, what ever we chose to do with the foot at that point in time, should provide almost immediate relief for the patient. This implies that if we apply a styrofoam pad to the left front and tape it on, we should almost immediately be able to go around to the right front and pick it up with more ease, implying comfort to the left front. The most traditional means of managing inflammation and pain is through the use of nonsteroidal anti-inflammatories (NSAIDs), including Bute, Flunixen and others. These medications can and do provide relief but we have to remember that they are only impacting a small facet of the inflammatory picture and when we use higher doses, we can inflict some serious side effects such as ulcers and organ damage. This is why so many are on ulcer medications at the same time. Often, we find that these NSAIDs do not provide enough relief for the patient and then we start to reach for more serious medications, including narcotics and constant rate infusions (CRI’s) of pain medications. I have never used narcotics in our patients as I have never had a need. What we have to remember with narcotics is that they are only blocking the perception of pain and not impacting the inflammatory process in any manner. In my years of managing these patients, I have found real value in the use of herbs, even along side of traditional therapies. Many herbs, including Curcumin and Boswellia, actually target the inflammatory process on a much higher level than those medications. When we realize that the inflammatory process is not only involved with pain, but also directly tied into the degradation of the laminae and associated decreased blood supply, then we come to see that managing this process on a more complete level is critical to success. Not only can we provide relief from pain, but potentially we can even impact the degenerative process, stabilizing the region at a much quicker pace. Deterioration of the laminitic patient is a direct result of an uncontrolled inflammatory process, period. So, in the ongoing laminitic patient, we have to assess all parameters from how we are addressing the foot to diet and impact on health, in order to find the weak link that is continuing to provide influences on the patient. In our patients, we will use a couple of different products to address the inflammatory response. If the patient is more painful and reluctant to walk, we will rely on the Cur-OST® Pure EQ® formula to help manage the inflammatory response, often dosing twice daily. Once that patient is improved, usually 5-10 days, we will either continue with the Pure EQ for another week or two or in most we will transition to the Cur-OST® EQ Total Support, which helps to balance the inflammatory response but also supports the hindgut, which is often involved especially in certain patients. My goal in most of these patients is to get them on and maintain on the EQ Total Support for the long term, in order to continue to promote a healthy inflammatory response.
- Enhance Circulation: Decreased circulation or shunting of blood within the hoof capsule is one of the main contributors to laminitis. The decreased blood circulation ends up impacting cellular health in that region and compromises the laminar tissue. Often, we feel an increased digital pulse, which would imply increased circulation, but this is not always true and actually an illusion to an extent. If we do venograms or vascular studies of the foot, we often see decreased blood circulation despite increased pulses. The circulation is impacted as a result of decreased nitric oxide (NO) production, which ends up contricting the blood vessels and reducing circulation. The decreased NO production is actually tied into the inflammatory process, based on current research, with various inflammatory proteins leading to a lowered nitric oxide production or inhibiting receptivity on a cellular level. Circulation can be improved through a variety of methods. Traditionally, we may use acepromazine, isoxsuprine, pentoxifyline, or even nitroglycerine. These medications can help in some cases, but not all. In actuality, if we control and improve the inflammatory response, then nitric oxide production can be improved as a byproduct. In other cases, we may implement amino acids such as L-arginine, which are used in the manufacturing of nitric oxide by the body. There are alternate pathways to nitric oxide production as well and include increasing the supply of natural nitrates to the body through dark green, leafy vegetables such as spinach. Again, as with other factors, if we stabilize the patient properly on all levels, then pain is decreased and the viscous cycle avoided. In our patients, I have found tremendous value in the Cur-OST® EQ Immune & Repair formula, as this product not only provides L-arginine, but also L-glutamine which can benefit the patient on a gut level as well. The EQ Immune formula also helps us to balance out the immune response, which is often involved in the over production of inflammatory proteins.
- Address the Hindgut: The hindgut is often an overlooked region in the horse in cases of laminitis. For several years, research has shown us that the GI tract is actually involved in many cases, demonstrating an overgrowth of lactic acid producing bacteria and creation of leaky gut syndrome. In cases of severe colic and even diarrhea, we often see laminitis which is secondary to endotoxemia or bacterial byproducts which instigate an inflammatory response in the patient. More often than not, this is associated with a deterioration of the gut lining and increased permeability. The bottom line is that in many of these patients, the hindgut is involved on various levels, contributing to ongoing inflammation and even sources of infection. We may have a patient with acute or even chronic laminitis, but the hindgut may actually be the source of the problem, so we need to address this concern. The use of ulcer medications and probiotics is not the solution in my eyes, but more often than not actually contributes to the problem or creates a new one. Ulcer medications are known to reduce absorption of certain nutrients, which impacts overall health, but more recent research has shown us that the change in pH associated with these medications, especially for the long term can actually contribute to bacterial overgrowths. Probiotics are a concern for me as there is little data to support their use in the horse, aside from Saccharomyces cerevisiae or brewer’s yeast. Many horses, especially metabolic prone patients, have an overgrowth of lactic acid bacteria, so the concurrent use of probiotics using similar bacteria should be viewed with question as they may actually be contributing more than helping. I prefer to manage these patients through inflammation reduction at a gut level and providing key nutrients to aid in repair of the tissue and stabilization of the microbial community, along with diet modifications. In many patients, especially those with an overgrowth concern, I have found great value in the use of the Cur-OST® EQ Rejuvenate, which is not only a whole food supplement supplying nutrients in their natural form, but also utilizes Hops and brewer’s yeast to reduce and stabilize the hindgut bacterial populations. Here are two research studies that we did regarding hindgut health and microbial influences. In the first paper, we revealed the potential problem and in the second paper, we demonstrated the impact of diet modification, inflammation reduction and use of whole foods to reduce the populations.
- Dietary Modification: Diet is another major area of interest when it comes to laminitic patients, especially those that are metabolic prone. The metabolic patients are viewed as being ‘carbohydrate sensitive’ in order to be more publicy correct and not offend them. They are overweight and often have increased insulin and sugar levels. The overall tendency is to put these horses on low starch diets which are specifically formulated and reduce their carb intake via hays with no access to pastures. I agree that carbohydrates are involved, but don’t view them as being the main instigator. The reason that I feel this is true is that most patients that undergo these dietary restrictions rarely improve clinically and many actually continue to gain weight. In reality, we have to step back and view it for what it is. First, a horse is designed to receive the majority of his/her nutrients from forage, so high quality forage should be provided. Second, most of these patients are overweight due to an over consumption of calories as compared to exercise. Essentially, too many calories and not enough exercise. The excess carbs are actually fueling the overgrowth of lactic acid bacteria in the hindgut and the associated secondary inflammatory response, so logic tell us we need to control them, but how do we do this and are we missing other factors? Third, research tells us that elevated insulin levels and decreased insulin sensivity are often induced as a result of uncontrolled inflammation, which impairs cellular function. In most of these patients on restricted diets, we may reduce carbohydrate intake but often we begin to note that the patient is nutrient deprived over time. They begin to have a dry coat, poor hoof quality and muscle mass loss. So, we need to reduce carbs but we need to also maintain a high level of nutrition in order to enhance cellular health if we really want that patient to respond for the long term. In our patients, we actually transition them to whole cereal grains including oats and sunflower seeds. It is true that these natural grains are high in carbohydrates, but we are feeding based on recommendations for these sensitive horses, averaging less than 2 grams of carbs/kg of bodyweight per feeding. This rougly equates to 1.3 lbs of pure, whole oats for a 1000 lb horse…actually more. To me, the commercial feeds are potentially contributing to nutritional problems and even hindgut concerns. Most of these feeds are highly processed and using nutrient sources that are not present in nature. In human studies, processed foods are associated with more gastrointestinal issues and increased permeability. Through the use of whole grains, we are providing some nutrition naturally as grains are also high in protein and micronutrients. We are not using them as primary meals, but more as a means of getting other supplements such as herbs into the patient. Along with the whole grains, we will actually use alfalfa, an alfalfa mix, orchard or timothy hay to provide a high level of nutrition. Some would say that their horse on a dry lot needs hay around the clock and if given alfalafa all day, they will gain weight. This is true on all levels and a horse should have access to roughage around the clock, but it is rare for me to personally dry lot a horse, especially for extended times. I want them to improve clinically and if we do our job right on all aspects, they respond rather quickly, then I try to get them out on pasture or a small lot in which they can pick at grass. I am concerned about overload of carbs on pasture, but again, if we do our job correctly, then this is not a huge factor in most. We will often use whole food herbs as sources of nutrients and some specifically to impact the bacterial overgrowth problem in the hindgut. When this is combined with proper foot care, properly addressing the inflammatory response and management of other concurrent factors, then the patients actually do quite well.
These 7 factors are the ones that we address in every patient. The key to success is addressing them properly and effectively. This can be accomplished more easily in some patients, while others prove more difficult. I think it is a matter of how many factors are at play in each patient as well as predisposing concerns. A horse with laminitis secondary to a fratured leg is different than one with metabolic syndrome. A horse with a twisted bowel and toxemia associated with colic is also a different situation. The factors are all the same, essentially, but the severity of the insult upon the body varies in intensity.
Another factor that is often overlooked is stress, which is inflicted upon the animal as a result of pain but also dietary and physical restrictions. We may not have a horse diagnosed with true Cushing’s syndrome, but if that horse is stressed for what ever reason, they will often have higher levels of cortisol which can impact health and contribute to tissue deterioration. In many of these patients, we have found value in the use of Cur-OST® EQ Adapt & Calm, which utilizes a concentrated Ashwaghanda extract and helps to support healthy cortisol levels. I also think it is important to get these patients out of their stalls and dry lots, allowing them to be a horse again. They can get very depressed, which fuels the process. Our goal is to get the patient back to pasture and I think this is possible in a high percentage of the cases. Many, despite doing well clinically, are confined to dry lots with no hint of grass due to fear of setting off the condition. This is no way for a horse to live and it is in my opinion that if this is what we end up doing, we are not managing some aspect correctly or we need to continue to seek answers.
The bottom line with all cases of laminitis is an uncontrolled inflammatory response. When this response is under-regulated, we have clinical problems. It is always much easier to deal with inflammation and health on a preventative level than one in which we have active clinical problems. That being said, I do believe that every patient can be helped, but the approach may be slightly different than what you may be used to hearing or seeing. Research has provided us with insight into this condition, but in most we just don’t apply all that has been discovered.
I hope this helps.
Tom Schell, D.V.M.