Sunday, April 3, 2011

Optimal hooves: Have low heels and short toes

Note: This is my last planned entry for this series. If you want to know about something else, please let me know.

After reading my post about frogs and soles you should intuitively understand the first reason why horses should have low heels: The frog needs to touch the ground to work correctly. But the following pictures should show you another reason why the heels need to be low. Unnaturally high heels tip the coffin bone onto its tip. Even in the absence of diet-based laminitis, high heels can cause a kind of mechanical laminitis by levering the coffin bone away from the hoof wall.

More x rays for you, I bet you didn't know you'd get good at interpreting these:

High heels and hoof wall separation, a vet would call this a rotation

High heels combined with a long toe
As the next graphic shows, if the coffin bone is left standing on its tip for too long, the bone will degrade.
See how the tip of the coffin bone has eroded? Note how far P2 has descended inside the hoof capsule.

Slipper foot, note the looooong toe, high heel, and how the coffin bone has started to erode
This one is interesting, the heel isn't that high but the sole is thin and the toe is long. P2 has descended inside the hoof capsule.
So what do you do when presented with high heels? You cut them off. You'd probably want to do this gradually if the horse has been in a bad way for a long time, maybe over the span of a few weeks, but you have to do it. It will take the coffin bone off its tip and will greatly enhance the horse's comfort.

Want to know how long toes happen? If the horse starts landing toe first for some reason - be it thrush, poor trimming, diet, or something else -  the laminae will start to tear. When the laminae starts to tear the body freaks out and sends in reinforcements to build more laminae, thus making the toe longer. This longer toe will cause even more tearing of the laminae, more reinforcements are sent, and the cycle goes on and on. What the horse ends up with is called a lamellar wedge: a nerveless, bloodless mass of excess material sort of similar to a callus or foot corn.

What do you do when you realize your horse has grown lamellar wedge? Cut it off. Seriously. I'm not talking about how farriers will rasp off the hoof wall at the toe (I don't think that's a good idea in general, thinning the hoof wall doesn't do anything good for the horse), I mean cut it off the hoof perpendicular to the ground- it certainly won't do your horse any favors if you leave it there.

Look back at those x rays and note that the coffin bone stays in the same alignment under the leg relative to the heels no matter how far out the toe has grown. Once you establish what the shape of the hoof should be based on the heel purchase, you can find exactly where your horse's toe should be.

This photo from the Swedish Hoof School further emphasizes my point, toe moves out but the coffin bone doesn't.

I took this photo of Coriander's right fore last November before I really understood this. See how long that toe was?
Isn't it great that I have examples from my horses of all the bad things? Bleh. Note the thrushy frog.
Remember my first post- where I said that front hooves are supposed to be round? If I superimpose a circle over this hoof based off the heel purchase and the white line at the quarters, look at how much toe lands outside the circle. I needed to cut that off.


This circle is actually a little big, but it still shows that he had a LOT of excess toe.
(If you want to check this with your horse use a duct clamp. They cost about $2 and are adjustable. Line one up on the bottom of your horses' hooves and see how round their feet really are. This works on the hinds too, just imagine that the circle gets pointy at the toe.)

But at that time I was still skeptical, and I didn't have nippers yet, so I only took half of it off and rockered the rest (A rocker is simply an angle rasped into the toe- a break-over aid.). Then we went for a ride. Holy cow! It was like he was a different horse. I couldn't believe how quickly he was picking up his front feet. It was amazing what a difference half an inch made.

Then something else interesting happened, he developed a toe callus.
I'm talking about that curved line that you can see between his hoof wall and frog. That's not his coffin bone sinking through his hoof - I know this because his feet have great concavity - that's where his hoof was breaking over when he moved. Notice how that curve is more round than the exterior shape of his foot? So did I; I took that excess off. Did that make him sore? Lame? Nope, not a bit.

One caveat: I probably wouldn't do that if the toe was really long (slipper foot) simply because it would remove too much hoof wall from the front of the foot. In that case I'd rocker the toe until the flare grew out a little more.

So there you go, there's almost a year's worth of hoof research distilled into a few posts. After all I've learned, I see horses all over the place with poor feet. All I can do is sit here and wonder, "How much better would those horses move if their feet were in better shape?" It's kind of depressing. Now maybe you'll see it too... you're welcome.

20 comments:

  1. Thank you! That was a neat series. Someday I'm going to learn to trim hooves - I plan on becoming a veterinarian that advocates for keeping horses barefoot.

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  2. Good idea, we need more of those! Did you know there are vets out there who actually believe horses should land toe first? Shudder.

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  3. OK, so I am a little confused (not unusual!) about trimming off the toe... What about the white line? Have I missed something?? Have a failed the course?? :-)

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  4. Nope, you've just told me that I didn't explain it very well.

    The white line is the laminae. I think this is a little confusing but what is called the white line is actually yellowish while the water line is white. Click on that last picture of his foot and you'll see it better. The yellow bit with the squigglies between the sole and the hoof wall is his white line. It's squiggly because the laminae are squiggly.

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  5. Yes, I see what you are talking about - thanks! I guess what I am having a hard time getting my head around is cutting off the front of the hoof. :-) Eliminating that wedge makes absolute sense to eliminate imbalance and coffin bone issues.

    Excellent series!!!

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  6. Well it is a little scary. Most people are more comfortable taking it back a little at a time, which is fine. The important part is that it does come off. If you leave it there it will just get worse.

    I was super pleased to find that toe callus because I was worried about taking that toe off too. His hoof told me exactly where it wanted the toe to be.

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  7. There was a farrier in our town who had an inordinate amount of laminitis occur with her clients. Every time we heard about another we'd wonder if it was diet or trimming. Now I'm really starting to wonder. This is good food for thought. So much information to digest, but I'll think about it every time I pick out my horse's feet.

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  8. Well that would be a little fishy...

    Diet is so, so important though. I'll be tackling nutrition research next. Ugh, so much chemistry.

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  9. This was great I learned a lot. I've seen a couple of x-rays of rotated coffin bones but didn't understand what i was looking for. Now I get it. Thanks to you.

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  10. That's great! I wanted to educate people- hopefully in a way that they would find interesting.

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  11. I'm a dedicated barefooter :) Great series!

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  12. i have one question from this post. how do you remove flare without thinning the wall?

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  13. Thanks Funder, barefooters unite!

    Lytha, hmmm... good question. Essentially you do cut the hoof wall off when you make the vertical cut to take that excess toe off. BUT- you leave the rest of the hoof wall intact because you don't rasp off the "outer shell." That way the hoof wall grows down at full width and with a nice strong connection to the corium through the laminae.

    Again, I wouldn't take all the excess toe off if the foot is really long. I know some people that would but I'm personally not that comfortable taking off more than 1/4 inch of hoof wall off the toe at a time simply because it takes too much of the hoof wall protection away from the foot.

    If your horse lived in a lot of rocks you'd have to be really careful with this, then again, if your horse lived in a lot of rocks he'd probably be wearing his toe back himself.

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  14. Really enjoyed your hoof series! I only did a weekend course last September, so I am still doing a lot of research and there is so much conflicting information out there it can be very confusing. Your hoof posts cleared up a few things for me. Thanks!

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  15. Xrays photos for us soon coming! WOW.... ;)

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  16. Fascinating and... makes me wonder if my ferrier is doing it correctly. He isn't a "barefoot" trimmer and he has said a few things that make me wonder.... He is definitely pro shoes. Sigh... I just need to keep finding time to study these.

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  17. I am so happy a stumbled upon this article/blog; job well done!

    Megan

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  18. so is that what that bump means? My mare has been developing that and I had no idea what it was but she is completely sound so I haven't been worry too much. I guess I need to take some more toe off.

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    1. Yes, but feel free to go slowly. Sometimes if the horse is strongly landing toe first, taking the toe back too far can make them sore. Take a little at a time and see how it goes.

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  19. I love to come back to these posts---that toe callus is shown up on Laz's club foot where I suspect his toe is actually too long (as well as heel)...I keep playing slowly w/ it. As I bring both down/back that callus is slowly crumbling away...as are the vertical cracks in his toe.

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