Heelpain - and in particular "Navicular"

Heelpain – and in particular… NAVICULAR
© by Carola Adolf NEP/fSHP

……There is this word again: "                            ".
When we talk about a soundness problem, this is one of the words we do not want to hear our  veterinarian say.
It usually is associated with the verdict that the “use-by date” of your horse is inevitably approaching and the beginning of “special care” has been reached in order for the horse to keep working.

I hope this article will be helpful to some of you who will be confronted with a diagnosis that includes the word “navicular”. We will talk about what “navicular syndrome” and “navicular disease” actually is (in plain English) and how it comes about – and, of course what we can do about it.

Firstly, let us look at a typical case scenario:
Say, over time you have noticed some small changes in your horse: He may not be as actively forward than he used to be and perhaps some of the “bounce” and spring in his step is missing. He steps short – or even miss-steps occasionally and perhaps there is the occasional stumble.
There is nothing “definite”, but once in a while there is a slight irregularity – and you start wondering….
Then you watch him – and you may start noticing that he lands toe-first (instead of heel first) – perhaps not every step, but often enough to see a definite difference….
All of a sudden he shows up a little lame – and then he is right again….
You think it might be the ground, or the weather – or your imagination.
Your farrier is - or is not - concerned and you decide to call the vet.

Your vet may examine your horse and perform a few tests, use a hoof tester, or even do nerve blocks.
He may or may not prescribe radiographs, but upon his or her findings, the diagnosis may be “NAVICULAR SYNDROME”
Or: “Pain in the heel (caudal) area”.
He or she may prescribe corrective shoeing and some medication to deal with inflammation and pain.

Everything may be fine for a while, but then your horse appears slightly “off” again, with real lameness episodes in between.
This time the vet recommends radiographs.
And indeed:
Now there are changes in the navicular bone! You are told that there might be a slight change from the normal shape, “lollipop
lesions”, de-calcifications, enlarged arterial holes (foraminae) – dark areas.
The “syndrome” has now become a disease:

Now what? The conventional approach may be more corrective shoeing and medication and then…..perhaps – as last resort:
Digital neurectomy (the cutting of the nerves, so the horse does not feel pain… or his feet - while the degeneration continues and worsens.)
This is usually the end of the horse’s ridden career.
When the nerves have finally grown back after a while (with more intricate branches), the pain will return.

Now you can see where this may lead.
In between “syndrome” and “disease” may be a long road of expensive treatments that may or may not bring relief, like for example a series of shock-wave treatments - or feeding Gallium nitrate or shoeing with pads or bar shoes etc. etc.

Unfortunately, most of the above only extend the “use-by date” if you are lucky - instead of removing the reason for what had been causing the problem in the first place:
An irritation that triggered discomfort and inflammation – and therefore changes in the tissue – that became visible manifestations eventually. In this typical case, it was the visible (on x-ray) change in the bone tissue of the navicular bone and/or underneath the pedalbone - usually around the attachment area of the impar ligament. These changes affecting the bone  itself are not painful (there are no nerves in the bone)! However the inflammatory processes and tissue trauma from pressure, are.

So, that would mean, IF we could actually find and remove the trigger(s) for the initial irritation that caused this progressive deterioration, we could not only prevent “navicular disease” but we could even rehabilitate and cure it?  The answer is yes.
The very least we can do is to stop further deterioration! 
Since the changes in the navicular bone itself (or the corresponding areas of the pedal bone) are not the cause for pain (bone has no nerves), there must be a problem that causes these changes – resulting in the visible evidence.

This means we must look for “something” that could be causing
- mechanical irritation and/or
- inflammation and/or
- a lack of nutrient/oxygen supply
Sounds too simple.

Let’s have a quick look at the structures involved:

The navicular bone (healthy) :

The navicular bone is located just “behind”  the coffin bone (see picture of dissection)

                                  Navicular bone
Deep flexor tendon                          

The navicular bone (also called “distal sesamoid”) and its “cousins”, further up the leg, the two proximal sesamoid bones (see below), have developed from tendon and they have two very important jobs:

1.to provide a smooth gliding surface for the deep flexor tendon around “corners” (joints, e.g. coffin joint and fetlock joint)


Distal sesamoid
(Navicular bone)

2.To increase the joint surface itself for more stability

So, what do all “navicular horses” have in common?

Simply put: A hoof shape that causes irritation to the structures within the rear of the hoofcapsule.

Usually that could involve one or more of the following:
·Excessively high heels
·Excessively high bars
·Underslung (collapsed) heels
·Overlaying bars

All the above is usually a result of – or in conjunction with - shoeing or incorrect trimming and inadequate lifestyle (lack of movement).

So, the conclusion and recipe for prevention and reversal of “navicular syndrome” and “navicular disease” is not another way of “therapeutic” shoeing or administration of better drugs, but removal of “external” deformities, restoration of function and physiologically correct hoofshape, and, of course, adequate lifestyle and movement on appropriate terrain.

So, yes – Navicular disease and the gloom and doom stigma of the traditional outcome for the horse may not be something you want to adopt without looking at the alternatives!

Heel pain as well as the “mysterious changes” to the navicular bone can be explained relatively easy and the reversal of hoof deformities, the original triggers, are indeed possible.

Depending on the severity and history (duration) of the external pathologies, a barehoof rehabilitation may take a few weeks but could also take several hoofcapsule cycles.
Good things take time.
And severe problems usually did not appear over night either: “Navicular disease”  may have been in the making for a long time and under the care of the best traditional hoofcare provider!

Perhaps the solution to “navicular syndrome or disease” is too simple:

a)Prevention of hoof deformities caused by  incorrect hoofcare and lack of movement.

b)Return to healthier hoofshape and FUNCTION, natural lifestyle with adequate movement on appropriate terrain.

The understanding of how the hoof functions needs to be respected and learning to identify “physiologically correct hoof form” is something that EVERY horse owner needs to do.
Trusting in traditional methods will at best prolong the useability, but will not bring back soundness.

So don’t give up if your horse has been diagnosed with the “N” word!

Look for a hoofcare provider who knows about rehabilitative trimming and hoof function - and remember that the body can usually heal and recuperate if your give it the chance  - by setting the right internal and external environment (homeostasis).

Re-discover what horses are and how their natural hoof should function and should look like!
Metal horseshoes do not fit in that picture.
Not a bit.

If you have any questions please contact me via email

Happy barefooting, all……. and don’t forget to re-hydrate* your horse’s hooves daily! (*with water……of course……)

Cheers, Carola

Coffin bone
Attachment area of impar ligament