Friday 15 March 2013

Flare, deviation and does it really matter?

This post is for CPT - she knows who she is, my barefoot buddy since the beginning, all those years ago! May you have many more rock-crunching horses, C :-)

There has been a discussion running on the Phoenix forum about flare and deviation in hooves. Its a subject that recurs fairly frequently and usually begins with someone asking how on earth you tell the difference between them.

Trimmers, other equine professionals and (of course!) owners often focus on flare (or deviation, or whatever you want to call it), not least because its visible. This is particularly so when a horse first comes out of shoes but you also frequently hear statements like "Oh yes, he needs to be trimmed every 6 weeks to keep the flare under control".

I've posted a lot about deviations, odd-looking feet, symmetry and so on over the years and its because the less I do to feet, the more interested I am in what feet do for themselves. Very often, horses know better than humans how their feet should work. We are typically more concerned with appearance but horses are only concerned with function and what works best to enable them to be as sound as possible.

In the past I've defined flare as being stretched white line and deviation as being a supportive hoof wall adaptation. That's ok as far as it goes, but what about a practical way to tell what you can safely trim and what you can't?
Think of it this way...In this photo, the hands of the adult are a vital support. Without them, little Jimmy (or whoever he is!) would fall flat on his face and there would no doubt be tears and trauma. In time he won't need them, of course, but for now the extra hands are essential.
Another photo, another adult holding a child's hand - but the purpose is quite different. Take away the adult's hand in this photo and the child would continue walking along quite happily. The hand-holding isn't supportive at all. 

This to me is the difference between flare and deviation. But here's the thing...The difference doesn't really matter

Of course, it does matter if you are proposing to take the hands away. In one scenario it would be a disaster. Similarly, if you are going to trim a horse, you'd better be pretty sure that you are taking off non-supportive flare rather than supportive deviation; if you get it wrong you will end up with a sore, less-sound horse. 

But the real beauty of flare/deviation and the reason it doesn't matter which your horse has (provided you don't want to trim it off!) is that it won't matter to the horse either - as long as you leave well alone and leave the decision to him! 
Why? Because flare, although ugly, is by its nature weak and therefore its benign - it doesn't matter (from a structural point of view) whether its there or not, it won't affect soundness and as the horse works on tougher surfaces the flare will wear away and disappear. If the flare is (as is commonly the case) the result of a previously poor diet or poor shoeing then as a healthier hoof grows down it will simply go away on its own.

We always used to be told that leaving flare in place would lever away at better-connected hoof capsule but that just doesn't happen because the flare is stretched white line  - its weak and compromised and is no match for healthy, well-attached laminae.
By contrast, deviation is an essential support. If you trim it away it will rapidly re-appear unless and until its no longer needed to assist in the limb's movement and load-bearing - and while the horse is without it, he will be less comfortable and less capable, especially on tougher surfaces.  So why would you want to take it away?

If you were the adult, and you weren't sure why the child was holding your hand, you wouldn't simply pull it away, would you? Don't you think it should be the child - who knows what he needs - who makes the decision whether to hold hands?


Krista said...

Fantastic analogy Nic and a great post. I've had a few conversations with people since B came home about his freaky feet ;0) They want to know why I'm not trimming the old hoof back to make it look 'more normal' and my answer of B will change it when he's ready isn't enough so I'm going to pinch this!

Nic Barker said...


cptrayes said...

Wow, thankyou - what a journey we've been on eh? We've religiously taken off flare only to see horn weakened for no reason but aesthetics. We've concientiously bevelled away bits of supportive toe, only to find that the horse moves worse, and finally we've found that if you stop worrying about what the foot looks like and concentrate on how well the horse moves, you get the right answer time after time.

What a fantastic analogy Nic, a stroke of brilliance there!


amandap said...

I get this and especially that healthy lamina can't be levered away. However, what about the supposed pain factor of leverage on weak lamina? Is there such a thing in your opinion? Are there nerves/pain receptors in the lamina anyway?

I do think the exercize movement factor is very important here. What about laminitics that are difficult to stabilize and therefore don't wear their hooves?

Maria said...

I think pain factor is incredibly important because for as long as the horse is in pain, it won't land properly and what should wear away, won't. But how you remove the pain factor is not so simple. I have had some success recently with a very difficult laminitic but it was through the use of gel pads that I managed to get the horse to forget the pain. Whether the pain was still there or she got used to toe-landing, I am not sure. But I am finally seeing heel-landing even out of boots. I still use the boots though, even for turnout. Never thought I would do that but had to think outside the box.

BruceA said...

Great blog post Nic.

I've always felt that flare and deviation are both supportive, they differ only in that the first is like scaffolding, the second is like a supportive buttress build to support what is above and around it once the scaffolding is taken away. Actually I think you used that analogy way back....

I'm lucky in a way - I have some tough ones and I've seen this kind of deviation appear and disappear as the horse goes through periods where he needs that support. It does so surprisingly quickly.

So do you feel it is wrong to back the toes of laminitics?

P.S> to be honest I've never felt comfortable about rolls either - why take away healthy functioning hoof wall and reduce the ground load bearing surfaces? If the horse is doing it for themselves fine, but why do it at all with a rasp? Makes no sense - just because wild horses on a sandy abrasive surface do it mechanically - it makes no sense for horses working in our conditions and on roads surely.

cptrayes said...

I think laminitics are a different thing altogether and they can only be dealt with on a case by case basis with the horse in front of you.

I know from experience that it is possible to drastically reduce pain in a chronic laminitic by a severe toe roll, but I wouldn't advise anyone to do it without seeing the horse concerned.

With flare and deviation you need to start from the point that you have a healthy horse with good laminar attachment coming down, even if it is not yet thre at the bottom. And after that then generalisations become much more useful.


Hannah said...

Thank you Nic, that is really, really helpful :)

Dom said...

I found this article extra helpful. My horse had a lot of trauma to his feet as a youngster and he doesn't have great conformation to begin with. He is sound and happy barefoot, but my trimmer always says, "Don't use him as an example of my work!" He has all sorts of flares that 'don't really matter' and everything you say in this post backs what my guy has been telling me for years :)

lyndac said...

Very helpful - thanks

BruceA said...

Would be really good Nic if you could do a blog post about your approach to caring for recovering laminitic feet.

Nic Barker said...

Thanks for all the kind comments - and yes, C, its been a heck of a trip, hasn't it?!

I agree that laminitic feet can be very tricky and I would never try to prescribe when to trim but I would say from my own experience (and that of some of the horses pictured in the blog post) that once a laminitic episode is over then leverage of flare doesn't seem to be painful.

I've seen some pretty ugly feet in horses who had suffered laminitic episodes BUT as long as the laminitis was under control the flare didn't seem to trouble them. I think for many laminitic horses solar corium inflammation is as big, or even more of a source of pain than the inflammation of hoof wall laminae but I'd be the first to admit that laminitis isn't something I deal with on a regular basis nowadays.

amandap said...

The solar inflammation being the biggest problem fits with my very limited experience of one (lol) pony. The pads I use taped onto her hoof when she has been acute seem to give more relief than anything else.

BruceA said...

" I think for many laminitic horses solar corium inflammation is as big, or even more of a source of pain than the inflammation of hoof wall laminae"

Biggest I'd say, absolutely what I've observed. But the debate about laminitics always seems to centre oin that toe area and dorsal wall. And why the choice of surface is really important - anything that packs the feet,like sand or mud, is uncomfortable, but concrete is actually not a bad surface as long as they have access to a conforming surface or bed. Pea gravel is great because it doesn't pack and stimulates the sole.

alimac said...

Is there ever a situation where the horse has such a strong wall that it will not break off as required?