What’s the deal with “Navicular?”

I’ll admit, I’ve had a lag in blog posts. Mostly, it’s been because I have wanted to write this post for a long time, and have simultaneously been dreading it. The internet can be a tough place, and I know I may get some push back for this. Or maybe not, maybe society will surprise me…. 🙂

Maybe it’s because I run a navicular-based Facebook group, maybe it’s because my horse has been diagnosed with navicular, or maybe it’s just because I am hoof obsessed, but I have been seeing a whole lot of posts lately about horses with navicular and owners getting a lot of different information in regards to the diagnosis. Call me naive, but I tend to err on the side of optimistic, and I’m going to share my thoughts. Buckle up, friends, this may get a bit bumpy.

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DIAGNOSIS

Owners still shudder when they hear their vet mention the word “navicular.” Most horses that have been labeled as having “navicular” were diagnosed through a lameness exam, perineural analgesia of the palmar or plantar nerves (PDN – palmar digital nerve blocks), usually followed by radiographs or even an MRI.

Before I continue, I want to say how appreciative I am of veterinarians, their hard work and desire to help horses, and admire their years of schooling to know what they know. I am NOT a vet. Where I can, I will reference vets here (and other “experts in the field”).

That being said, many vets will admit there are a few problems with diagnosing navicular as I mentioned above.

  1. Numbing the nerves that run down the back of the pastern doesn’t just numb the navicular bone. In fact, these nerve blocks can actually numb much more of the foot than we realize. Meaning a PDN meant to just numb the navicular “region” can also be blocking pain from say, laminae, or thin soles, etc. (Dr. David Ramey, 2018).
  2. Veterinarians found that when a pile of “navicular” x-rays were thrown on a table, they could not determine which ones belonged to sound horses, and which ones belonged to lame horses. In fact, they found that not only did x-rays not give the best view of the navicular bone, but that many sound horses have funky looking navicular bones, or bones with “holes”/channels/other “issues” (Dr. David Ramey, 2018).
  3. MRIs can show a whole lot more than we ever thought we would want to see. Old injuries, new injuries, what’s causing pain, what isn’t causing pain… you get my drift. As humans, if a doctor performed an MRI on us and pointed out some pathology on the results, we can look at it and say “well, yeah, but my back doesn’t hurt there.” A horse doesn’t have this advantage of such clear communication. Not to mention, the hoof has what feels like an infinite number of structures that can be affected. Who is to say that what we find on an MRI is the ACTUAL source of pain?
  4. Dr. James Rooney found that a horse can have soft tissue damage without bone damage, but never found a case where a horse had bone damage without soft tissue damage. It seems, he concluded, the soft tissue damage leads to the bone damage, and often, this soft tissue damage comes from toe first landings (Pete Ramey, 2005).

This all being said, I still think that these diagnostics can be very valuable. At least we will know with a PDN if the pain is in the hoof and not higher up. Radiographs can help with showing progress or change in the hoof and a baseline. And MRIs can give you a lot of information you wouldn’t otherwise have, and information isn’t a bad thing!!! Just make sure that you don’t start to fixate on this information, and end up missing the forest for the trees, so to speak.

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“Navicular skyline view”

TREATMENT

So, you’ve gotten the diagnosis. Your horse has “navicular disease” (most commonly used to refer to x-ray changes seen on the navicular bone), or “navicular syndrome” (no radiographic changes present). You’re likely freaking out, wondering how to keep your horse the most comfortable before this terrible “degenerative disease” takes over. After all, that’s what we’ve heard, right?

So you try bar shoes, or even add wedges. “Take the strain off the navicular bone,” they say. You inject with Tildren or Osphos, because that’s “for navicular.” You start isoxsuprine to “increase circulation,” and maybe even add in some previcox for pain. Some of these seem to help, some don’t, but your horse eventually is lame consistently and you can’t seem to help him.

First, let’s get a few things out of the way…..

  • Rood and Riddle recently held a conference where Tildren and Osphos were discussed. Veterinarians found that these drugs, bisphosphonates, delayed healing in the rest of the body for up to TWO years after even just one injection (Bramlage, 2018). The injection didn’t allow the osteoclasts and osteoblasts in the body to do their job of remodeling bone, as they do to fix bones when they break or fracture. Couple this with the fact that Rockley Farm has seen some evidence of navicular bones remodeling damaged areas with proper rehab, and I’d say we want those osteoblasts and osteoclasts to do their thing.
  • Isoxsuprine basically does nothing. (Dr. David Ramey, 2018).
  • Wedging a horse with heel pain shifts the focal point of pressure in the hoof, and decreases the weight bearing surface area during landing, actually leading to more damage. So while wedging might help with pain in the short term in a “navicular” horse, in the long term it likely leads to further degeneration (Kauffman/Bowker, 2011).

I don’t like wasting money. I don’t like others to waste money either.  So what do we do for these “navicular” diagnosed horses? Oh man… degenerative diseases are the worst.

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WAIT A MINUTE. I’m going to stick my neck out and say calm down, take a deep breath, it’s actually possible that your horse doesn’t have a “degenerative disease.” Notice, I didn’t say that your horse doesn’t have pathology, or doesn’t have navicular bone changes, or doesn’t have x/y/z that your vet diagnosed. I’m not a vet, remember? I’m just here to give you hope. There isn’t enough of it in the world nowadays. Let’s travel down the “hope” path for a bit. Can’t hurt, right?

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A Different Approach

So what do we do?

FIRST THINGS FIRST. Remember where I said that a PDN might have numbed more than just the heel? What if that pain was actually coming from low grade/”subclinical” laminitis, or thin soles, or unhealthy frogs?

  • Start with diet. Diet sensitivities and mineral deficiencies or imbalances can cause weakened laminae connection, lack of ability to grow healthy horn, and decreased frog health. For more information on diet, click here for “Feeding the Hoof.”
    I’ve seen many horses that suddenly can walk on any surface without “feeling their feet” just from a few simple diet tweaks. Without that painful compensatory movement, suddenly their body is functioning better all over. They’re less stiff, their muscles are moving as they should, and they’re sounder!

But, let’s assume the PDN was correct and the pain IS in the heel. Remember I said I don’t like to see people waste money? So while making some (relatively inexpensive) diet tweaks, let’s investigate the heel.

  • Treat aggressively for thrush. I personally love Red Horse Products, and use “Hoof Stuff” for the deeper crevices and “Artimud” or “Field Paste” for the shallower issues. For more stubborn problems, or for abscesses, I like Oxine AH. Pete Ramey has some great tips here for soaking and for his own “goo.” And hopefully, those small diet changes you made will keep future thrush at bay.

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“BUT what if the pain ISN’T from diet, and ISN’T from thrush?” you say. My first response is a knee jerk reaction – are you sure? Get those two things above in place and then we’ll talk.

….And now we’re talking 😉

Yes, it’s possible your horse’s “navicular” pain is coming from soft tissue damage and/or bone damage.

In that case, we need to get the feet as healthy as possible. After getting the diet and thrush in line, we need to focus on movement and hoofcare.

  • Heel first landings build strength, help to rehab soft tissue and stop further bone damage, and can allow the other hoof structures to help the foot “forget” some other pathologies, in so many words. I should clarify.. heel first landings in which the frog, sole, and hoof wall share the weight-bearing load, to prevent peripheral loading, will help to make the caudal hoof healthier (Dr. Robert Bowker, 2007). DO NOT ride a horse if they are not landing comfortably. To get a horse landing comfortably, conformable surfaces (such as pea gravel) can help stimulate the weaker areas while providing comfort, and in many cases boots and pads can be very helpful in getting a horse confidently landing heel first. Do NOT work or force a horse to move that is landing toe first. This can continually exacerbate issues by reinjuring the internal structures. 

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  • Good hoofcare. This is going to look different for every horse in some ways. Not every horse will (nor should they!) have the same trim. Join Hoof Care and Rehabilitation on Facebook. Talk to your farrier or trimmer. If you don’t have one, check out the PHCP website and find someone local to you who can help you.
  • Read, and study, and learn. Check out “Feet First” by Nic Barker, “Performance Hoof Performance Horse” also by Nic Barker, “Care and Rehabilitation of the Equine Foot” by Pete Ramey, and “The Essential Hoof Book” by Susan Kauffman and Christina Cline. Arm yourself with knowledge. Don’t stop educating yourself. Read more about Rockley Farm’s protocol for navicular, since they deal specifically with these issues.
  • Listen to these podcast episodes for case studies of navicular rehab, examples of horses returning to soundness, and various things to consider with navicular cases.

Think Outside the Box

It’s also possible your horse doesn’t improve with the steps listed above. Before throwing in the towel, read this post by Rockley Farm and consider if your horse might need a “wonky” looking foot to be comfortable. Talk to your hoofcare provider about watching how the horse naturally wears, seeing what you can leave more than what you can take away. Take a leap of faith and see where it leads.

Is it possible your horse can’t be rehabbed from its navicular pain? Yes. Is there hope and a chance for soundness even in some of the “scariest” cases? Yes.

You never know how sound a horse can be until you try.

For some inspiration, check out this video of horses with a history of bone damage, soft tissue damage and navicular diagnosis:

If you need help, encouragement, or a listening ear, there’s a bunch of us on Facebook that would love to walk with you on this journey. 

Interested in a crash course on rehab? Check out a free webinar I did with Wendy Murdoch here.

Looking for a guide to help you adjust diet, watch for proper movement, and track progress for your navicular rehab case? Check out The Humble Hoof Rehab Guide here. 

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