C6/C7 Malformation

This is my story of Sox.

Sox came to me as a very sweet, very talented, yet very immature rising four-year-old in October 2014. I was excited about her bright future but I was prepared to give her time.

I am very much against rushing the training of young horses. I am an advocate for building them up slow and steady and I really took my time with her education. Yet despite my best efforts, things quickly fell apart. And just four years after she arrived, I found myself reading her autopsy report.

My name is Katrin Kuenstler. I live in the Perth Hills of Western Australia, and I am a dressage rider, equestrian coach, trainer and pilates instructor.

Overall, in the three years I had Soxy under saddle, she only advanced very slowly and I kept feeling I was treading water, rather than moving forward.

I also kept wondering why she didn’t seem to develop more musculature in the topline, her back and neck, especially given that I did all the things every vet or physio recommended: hill work, pole work, in-hand training, lots of long and low stretching, etc.

I put it down to her being young (mind you, she was a 7-year-old by then), and her being a Warmblood, and thus, taking longer to mature than others.

By 2017, her once very nice athletic movement appeared to have gradually deteriorated, rather than improved! And alongside it, her behaviour got worse.

The stress signs whilst tacking up and under saddle increased slowly but surely, the jaw clenching, ear pinning, tail swishing, etc., became more pronounced.

She was very grumpy in the paddock and although she never actually did bite or kick, she threatened to do so whilst being caught and rugged, brushed and saddled.

She was very reluctant to go forward and dragged her hind legs over the ground either with or without a rider on.

All this despite arranging regular saddle fits, therapeutic massages and feeding her all the right supplements. Soxy was always very sore over her whole back and down her glutes. But despite this, she was never lame and so, in the eyes of many vets and body workers, she was passed as fine – just weak.

But despite the lack of a diagnosis, I could not rid myself of the feeling deep down in my gut that something was not right with my mare, I just couldn’t pin it down.

One of the many things, I have learnt as a result of this trying process, is that we have to give our horses the benefit of the doubt. We have to listen when they try to tell us they are unhappy, in discomfort or pain.

I had her ‘looked at’ by many different experts in different fields – vets, physiotherapists, chiropractors, energy workers… no one seemed able to pick the problem. I became progressively more frustrated, and since there didn’t seem to be a physical cause for her behaviour, I decided Soxy was just being ‘difficult’ and didn’t want to ‘play’ or ‘perform’.

I drew upon the ‘problem horse’ expertise of my good friend and horse trainer Shelley Appleton. Shelley loves a good challenge when it comes to unpicking a horse’s mind and emotions, and got right into working with Sox.

After about four weeks of training, which progressed at a snail’s pace, Shelley’s verdict was that Sox actually did try, but was somehow limited, probably due to an underlying physical cause.

After much research, Shelley suggested that Soxy might be suffering from Wobbler’s Syndrome, a condition where the spinal cord becomes compressed because of a narrowing or instability affecting one or more vertebrae.

With that in mind, I took Sox to the vet and asked for a thorough assessment with neck x-rays, and discovered an irregularity in the two lowest cervical (neck) vertebrae – C6 and C7.

This area of the neck is difficult to x-ray in the horse, so an ultrasound was performed which detected a mild deformation of the C6 vertebra and inflammation in the C6/C7 joint.

The C6/C7 joint was injected with steroids typically used in the treatment of orthopaedic disease such as osteoarthritis, in the hope that this would reduce the inflammation.

After her treatment and a bit of rest, things looked quite promising. Sox seemed pain free, ‘happier in her own skin’ and overall more contented than she had been for a long time.

When I started to work her again, a week or so after she had been injected, she seemed much more willing to give things a go and her movement had reverted to her natural athletic, floating gaits.

I spent a few weeks working her from the ground, doing a lot of lungeing and in-hand work, and progressed to light work under saddle which also seemed to go much better – at first…

Because after just a few months, things started to fall apart again.

Sox started to show strong signs of discomfort again and although it still seemed as if she was doing well physically, she could just not cope with being ridden. Her anxiety levels rose and she just shut down.

This had been going on for too long. Sox was telling me loud and clear that she just could not cope. The pain in her neck started to re-appear and to top it off, possibly as a result of pain and stress, she developed gastric ulcers.

I had hoped that I would be able to work through the issue and build up her musculature correctly to support the damaged joint, however, I could not help her feel well. So, I made the very difficult decision to let Sox go and put her to sleep.

I had learned that Sharon May-Davies would to be in WA for one of her very sought after Whole Horse Dissection courses and I made Sox available to use for the autopsy.

Sadly, in the two months leading to the dissection, Soxy’s physical and mental state deteriorated in front of my eyes. I could not ride her anymore; in fact, on the last bush ride I took her on, she was so unstable and unbalanced on her feet that I felt very unsafe! She hardly moved around in the paddock, lied down a lot and was very anxious to be touched, groomed or rugged.

The extent and significance of Sharon’s dissection findings are incomprehensible.

It turned out that Sox’s C6/C7 malformation, a condition now known as Equine Complex Vertebral Malformation (ECVM) was only the tip of the iceberg. I decided I would not attend the dissection myself, but received descriptions and a comprehensive written report.

While some of the issues that Sox suffered from would have been subsequent conditions or possibly caused by trauma, most of them had to be hereditary.

Sharon has dissected hundreds of horses and to that date had not come across anything of Soxy’s scope yet.

She told me that, had Sox not been euthanised, she would have most likely suffered a very painful death from organ failure caused by dysfunction – she found her spleen and kidneys underdeveloped in size. She said she was glad I had not suffered a catastrophic accident. Horses with this type of cervical malformation are very likely to feel very unsteady on their feet at all times, so they will try to rebalance their body constantly and this might lead to them falling over.

This, in turn, might lead to strains in the soft tissues or more serious damage can be caused if the horse collapses from losing balance.

In addition to the ECVM, Sharon identified kissing spines, orteochondritis (OCD) lesions, bone spurs, muscle tears and nerve impingements, to only mention a few.

All of those fancy medical terms simply mean that this beautiful, well-bred mare would have been in chronic pain from the moment of birth, she never had a chance.

The reason why I share Sox’s story is to raise awareness of ECVM – a condition that is affecting many more horses than we think!

Not only is it painful for the horse, but the neurological dysfunction makes it very dangerous for the rider!

So my message is that, when in doubt of your horse’s behaviour, always assume a physical component, and I would go further and suggest to investigate the cervical spine – even if as an exercise that rules out that your beautiful horse is suffering form this condition.

Furtunately, ECVM awareness has been rising thanks to Sharon and other researchers investigating and publishing scientific studies around the world, showing that the occurrence of cervical malformation is on the rise.

As a result, radiographing the neck is now suggested as part of the pre-purchase vet check. Since this condition is congenital (with evidence shown on both maternal and paternal sides), horses with this condition should be identified and not be bred from.

One of the many things I have learnt as a result of this trying process is that we have to give our horses the benefit of the doubt. We have to listen when they try to tell us they are unhappy, in discomfort or pain.

We are all too quick to label them ‘stubborn’, ‘lazy’, ‘arrogant’; I myself have called my horse every name under the sun. But a horse can only express distress by displaying bevaviour which we consider disobedient or ‘naughty’.

They simply have no other way to communicate their plight to us… they don’t speak human!

So, please trust your intuition. No one knows your horse as well as you do. You live with them; they are part of your family. Learn to listen and observe, and even if it takes some time and, provided you don’t stop asking questions, you will find the answers. We owe it to these extraordinary creatures!

I miss Soxy a lot. The only source of comfort left for me is that I kept questioning and searching. That I did listen to Sox and that she is now in a better place and finally free of pain.

Soxy’s case will be included in Sharon’s future lectures and I am glad that she is able to educate people around the world.

The participants of Sharon’s dissection put together a lovely book with words of thanks and empathy and I would like to quote one of the messages:

“May the ripple of her legacy continue forever.”

Sharon May-Davis BAppSc (Equine), MAppSc, has published a study on The Occurrence of a Congenital Malformation in the Sixth and Seventh Cervical Vertebrae Predominantly Obseverd in Thoroughbred Horses. You can read the abstract here.

Equine Complex Vertebral Malformation (also known as C6/C7 Malformation or ECVM)

The C6/C7 Malformation is a skeletal malformation and cannot be corrected. It is congenital, i.e., inherited, as it has been noted in utero and so is present from birth.

The horse’s skeleton is designed to build a steady framework on which muscles, tendons and ligaments can attach to and hence provide the utmost stability yet wide range of motion. This is what enables the horse to not only carry a rider on his back, but also to perform in various Equestrian sports.

Horses that suffer from a malformation in their cervical spine will be limited in the flexion of their neck and develop muscles very slowly and irregularly. They are lacking stability as well as flexibility and will therefore, be limited in their performance as well as their every day life. Furthermore, they might suffer from chronic pain.

In severe cases, horses can display symptoms associated with Wobbler’s syndrome due to the deformity of the spinal canal which might cause pinching of the nerves that form the spinal cord.

This can result in problems with the horse’s proprioception, meaning they can find it difficult to be aware of where they place their feet – comparable to a person who is drunk. These horses might become very unsteady on their feet; stagger; stumble; sometimes even fall.

You can see how dangerous that would be for you when you are on their back!

For a horse that suffers from ECVM, their body is in a constant state of imbalance trying to adjust to likely spinal compression.

Straining some soft tissue in the legs is common or tearing muscles when the horse is falling over.

Some symptoms which Soxy displayed and which are commonly known to be related to Wobbler disease are: flicking her front feet; dragging her hind legs; swaying when walking; she was feeling very insecure on her feet under saddle; she had difficulties going down hill; backing up and scrambled while floating. She was also not able to bend her neck laterally and had trouble picking up her hind feet.

This article was published in Horses and People November-December 2019 magazine.