Laminitis/EDE...either way a modern epidemic?

The picture right shows a horse with historical signs of EDE characterised by a change in conformation of the horn at the back of the hoof including the coronet band-notice how it raises up at the quarters before dropping down toward the heel bulb as a result in the change in conformation of the lateral cartilages.  The horizontal hole is a where the farrier attempted to cut out an abscess at the coronet band which occured as a result of the EDE and laminitis a few months previous.  The growth rings also show increased growth at the heels from metabolic imbalance and increased stimulus from a heel first landing from pain during laminitis.  This horse is now sound and has a healthy hoof capsule and no signs of EDE as a result of AEP.  Incindently the horn beneath the coronet band where the abscess was 'relieved' still produces unhealthy cells more than 2 years later and the hoof wall beneath it is susceptible to minor outer hoof wall infection.

I am not a self professed expert on laminitis, however; there are some self proclaimed experts on the subject who have, in my opinion, not quite understood the causes of the disease and therefore their treatment protocol is insufficient.  I am a DAEP (Degreed Applied Equine Podiatrist) with an understanding of true foot function as defined by AEP (Applied Equine Podiatry) and can appreciate, through physiological sequencing; the ‘hows’, the ‘whys’ and what to do about the condition and most importantly I aim to prevent it from occurring when it is within my means to do so.  I will direct anyone interested in laminitis and true foot function to read an article which stands to revolutionise the treatment of the laminitic horse.  The man who wrote this article does not stop asking questions and has some pretty strong theories on true foot function.  Click here to go straight to the article.

If you don’t agree with what this expert says, I’m sure he would welcome your comments on the subject and would encourage anyone to try and disprove his theories.

I for one have repeatedly tried my very best to apply the theories and can whole heartedly say that I am always surprised by how incredible it is in promoting healthy feet.  This may come as a shock to any of my clients who are reading this but after years of putting my faith in traditional farriery methods and being disappointed by the trail of disease and poor performance left behind as a result of this (and in providing what I believed was a healthy environment, but wasn’t), I just can’t help but enjoy every satisfied and secretly surprised feeling every time I trim a horse’s hoof and set a horse up for health and performance!!!

So, back to laminitis.  I urge you to learn about this straight from the organ grinder (KC LaPierre) and not the monkey (me!) by reading the above mentioned article.  But if you can’t be bothered or find it difficult to decipher, I will endeavour to list a few key points:

1) Laminitis simply means inflammation of the lamellae which are found all along the dorsal (front and side) of the pedal bone and lateral cartilage in the horse’s foot.  The lamellae found at the front of the pedal bone are often the most commonly affected with typical laminitis as its foundation is bone and is therefore (when considering foot function) most susceptible to strain.

2) Let’s consider what most of us imagine when we visualise a laminitic horse; painful stance, obvious lameness and sets of x-rays ordered by worried vets concerned with rotation and the beakdown of the lamellae.  And therefore with nothing holding the foot inside the hoof, there is a risk of founder and sinking with that most scary of prospects; a sole penetrating pedal bone.  Yes, we should be concerned with rotation but why?  The conventional belief is that the lamellae are responsible for the position of the pedal bone within the hoof (or in other words, the lamellae are responsible for preventing the horse’s bony column from collapsing through the hoof capsule).  In Applied Equine Podiatry (AEP) the lamellae are indeed found ‘attached’ to the surface of the pedal bone but their function is to provide physiological support by producing inner wall, provide protection via its receptive ability and to perform an important role in energy dissipation via appropriate circulation.  This is quite different to the role of lamellae believed by most vets and hoof care providers.  In AEP theory, the internal foot (Internal Arch Apparatus) is in fact suspended within the hoof capsule; this also challenges conventional theory on foot function (click here for more info).

3) So, in conventional theory, laminitis and the resulting rotation of pedal bone is where a deviation occurs from the normal alignment of the bones around a joint, as seen on those dreaded x-rays.  However, AEP believes stress results in the forces that cause rotation, but those same forces are used by nature to place the affected joints’ load surface into balance.  Or to put it another way, changes seen on x-ray are a result of stress which causes modelling or remodelling of bone and cartilage and these are appropriate changes as a result of stress.

4) So why should the pedal bone ‘move’?  Actually, the laminitis is a symptom of another condition called Equine Digital Elastosis or EDE; equine meaning horse, digital meaning of the foot and elastosis meaning a loss of elasticity.  To cut a long story short, metabolic stress causes the soft tissues in the body and the foot to become less elastic which makes them less able to return to their original shape.  Now, the back third of the foot is comprised entirely of soft tissue and is connected to the pedal bone via cartilage.  As the horse moves, the lateral cartilages (which mostly form the conformation of the rear third of the foot and are responsible for growing the hoof wall in this area) move upwards and outwards independent of one another when the hoof lands and meets the forces from the ground and when the weight of the horse loads from above.  In EDE, the lateral cartilage doesn’t want to return to its original shape and position within the hoof capsule and this eventually causes them to change conformation.

5) So?  Why does this result in laminitis.  Simply this…by their attachment to the pedal bones, the upward movement and new position of the lateral cartilage puts stress on the pedal bone and what is attached to this?  The lamellae!  So the lamellae take the strain too and the horse feels pain due to inflammation.  In severe cases, the horn can suffer a loss of integrity to the laminar and become attached, although the physiological changes are likely the same.  In other words, the mechanical stresses created by the metabolic imbalance affecting the soft tissues of the foot (which are the support and suspensory structures as identified by the definition of the Internal Arch Apparatus) may actually result in the mechanical separation seen in more serious cases of laminitis.

6) So if we can recognise EDE, we may be able to prevent more serious damage or laminitis.  To do this, one must understand the root cause (metabolic imbalance), remove the cause of stress as much as possible (which often means management changes and pain relief), assist the horse’s own healing from a holistic point of view, and stabilise the change in conformation of the lateral cartilages long enough to stabilise the metabolic result of this and therefore avoid rotation and separation.

7) DAEP’s are trained to recognise the signs of early EDE and during consults can respond quickly to changes seen and/or from responses identified by simple tests.  However this requires knowledge of true foot function as identified by AEP.  A DAEP can also use tools aimed to address the changes and assist the horse to return to performance.  Most importantly, DAEP’s adopt a holistic approach towards the practice of AEP and the High Performance Trim method is proactively supporting a healthy foot.  Thus, one would hope that one stands a better chance of your horse not actually getting EDE if one employs a DAEP in the first instance.  And if your horse does suffer from EDE, then a team effort with your vet and DAEP will help no end in preventing more catastrophic development of the disease!

8) The causes of EDE are simply a disturbed metabolism.  This can be as a result of toxicity (which itself has many causes) or faulty endocrine (hormone) system (from insulin resistance for example).  It can be as a result of stress, which may be physical (from pain for instance), emotional or mental.  What it all boils down to is this…..an inappropriate environment can cause stress and a proper environment promotes proper stimulus.  And we all know that proper stimulus is required for growth or health!  But I will talk about environment another time!

So there you have it.  Laminitis is a symptom of EDE and acute laminitis or chronic laminitis is all EDE at different stages.

For more information on Applied Equine Podiatry, EDE Laminitis or proper foot function and to locate a DAEP or learn to trim your own horses, go to the Institute of Applied Equine Podiatry’s website: www.appliedequinepodiatry.org.  Or, if you want my help, give me a call!