ROB JACKSON BVetMed, MRCVS qualified from the Royal Veterinary College, London in 1996 with a final year elective project in the pharmacology of equine acute laminitis. Whilst a student he competed for both the University of London Riding team and the Polo team, was a member of the Royal Veterinary College Riding Team for a record five consecutive wins at the Association of Veterinary Students annual Riding competition, and competed overseas with the International Association of Student Riders.
His first veterinary role was in a mixed practice in Surrey where he set up a new equine intensive care facility and learned the rudiments of equine physical manipulation. After 18 months he moved to the equine department of a large practice in Somerset and was a founder member of the South West Equine Medicine Discussion Group. He later trained in equine arthroscopic joint surgery and fracture repair and became both the chief surgeon at his own practice, and a British Equestrian Team vet attending multiple international championships including the World Equestrian Games in Kentucky, 2010.
Over the years he has competed in eventing, dressage, show jumping and showing; he has also jousted at several castles, holds the British Driving Society stage 4 professional coachman qualification and is an associate lecturer in Equine Sports Medicine for the University of Chichester. He is Equine Veterinary Advisor to the National Trust. Since 2015 Rob has been a director of The Horseback Vet, an international equine skeletal mobilisation service, geared towards promoting freedom of skeletal movement.
Horses are horses. Barring breed discrepancies (and, in the grand scheme of things, all of those are pretty minor – even the Arabian ones), all of our horses and ponies have exactly the same basic structure and functions. Their skeletons are all virtually identical, with the same muscles and tendons exerting movement forces on the same joints, which in turn are stabilised by exactly the same ligaments. The blood supplies feeding all the living tissues are all essentially the same in every animal as, basically, are all the nerves.
The uses we put our horses to are, of course, very varied; as too are the situations in which we keep them; and their level of fitness is one of the greatest – and yet tragically least recognised – variable of all.
And so to the movement of healthy, uninjured horses: breed (and breeding), size, conformation, skeletal maturity, training, foot balance, shoeing, saddle and tack/harness, the level of physical therapy support, nutrition, rider’s weight/balance/skill level, weight and balance of carriage/ cart/implement being drawn, etc, etc, etc all come to the fore and can produce huge variations in the way horses move. If you add ill-health or injuries into this mix then movement can be massively impacted – or, sometimes, very subtly.
As vets we are taught to recognise, diagnose and treat illnesses and injuries. Some of these are very straightforward, whilst others are complicated, multi-factorial, and difficult to diagnose and/or successfully address. In between these two extremes is a whole spectrum of pathologies that can cause any given horse, any given problem in any given situation.
But let us leave pathology to one side for the moment and concentrate instead on the movement of the healthy, non-injured horse. Picture an adult horse with established form in whichever discipline you choose; the horse is as fit as it ever has been, it is ridden by the same (reasonably skilled, competent and balanced) rider of unremarkable body weight. The yard is managed well, with sensible nutrition choices and enjoys a good support team in terms of foot care, physical therapy, saddle-fitting, dentistry, veterinary care, etc. The combination has regular good-quality training and the horse is worked on a variety of surfaces and even does little bits of cross-training exercise, outside of whatever its discipline would usually be concentrating upon. Essentially, we’re talking about a really pretty good situation.
And yet the horse has started doing something abnormal. Perhaps it has developed a one-sidedness that has not been experienced before; perhaps jumping is causing problems in a way that hasn’t previously been seen.
All of the obvious things have been checked out: there’s no detectable lameness or anything else that suggests pathology. Saddle, girth, bit, teeth, feet, nutrition, etc all check-out fine. There may not even be anything of particular note regarding musculoskeletal palpation. Blood samples may have been taken and revealed no significant findings. Basically nothing has changed and everything we check appears to be fine. Perhaps it’s in the horse’s head? Certainly possible – it is, after all, a horse...
Having sensibly looked into all the most common likelihoods we do need to consider how the horse is actually moving. As mentioned, there’s no detectable lameness. Nothing that would prompt nerve-blocking. Conventional imaging, if performed, has yielded no significant findings.
But is the horse moving freely?
Horses share a lot in common with cats when it comes to their normal free movement. This isn’t crazy talk; to some extent a lot of free-moving dogs share some things in common with cats, too, but horses perhaps do so more. There some genuine anatomical reasons why this is the case.
If you watch the way their bodies move in walk horses and cats have a remarkably similar serpentine movement through their backs. Sure, it’s easier to see in a race-fit, clipped thoroughbred but that same sway of the horse’s hips as the hind limbs move produces a very similar snaking motion, transferred forward through lateral bending of the thorax and ending with a (very) mobile neck balancing the movement of all the limbs and torso. The fact that it is easier to see in the sleek racehorse does not mean it is not happening in any other free-moving horse or pony (or ass or donkey). You might just have to look more closely.
In trot and canter (and galloping) this movement changes dramatically, due obviously to what the limbs are doing but also, critically, the way the movement of the horse’s body shifts in order to produce each gait. This is the scenario of the free-moving horse: the body and limbs working together to produce the appropriate movement for each gait, direction change, stretch, jump or whatever it might be attempting to do.
So what happens when this synergy is disturbed?
Horses, as everyone knows, evolved as grazing herbivores and reasonably low down in the food chain. An individual’s survival depended on being able to continue grazing (which, by definition, involves constantly moving to find food) and on being able to run away from predators. It is unsurprising then that they’re generally pretty good at keeping moving even when things aren’t going well in terms of illness or injury. The great majority of today’s equines are masters of compensation – if something isn’t working as it should do, then they quickly find a way of moving differently in order not to rely on the bit that isn’t working. This is easy to see in the lame horse, that will shift its weight off the sore limb in order to keep grazing and be able to attempt to get away from danger. It might not look good – and, indeed, it may really not be good but it could allow the horse to basically keep going. Every vet, farrier, physical therapist, etc will have seen the compensatory issues which can arise from these “coping” behaviours. Horses with pathology affecting their spines, or horses with pain from a poorly fitting saddle, etc have to similarly adapt their movement to one degree or another in order to “keep moving”. Those adaptations may involve a change in back movement, but may also involve changes in limb movement.
There are also far more subtle reasons why horses might stop using their backs in the way they were intended to. It stands to reason that free moving backs are a product of a large collection of free-moving spinal joints; anything that affects even one of those joints has to be accounted for by the rest of the horse. Now obviously an inflamed, osteoarthritic joint would fall resoundingly into this category, as would a number of other articular or peri-articular pathologies – and we would always want to rule those out at the earliest opportunity. However, horses, like people, can suffer from transient nonpathological disturbances to free-joint movement that can require just the same adaptive changes in the rest of the horse’s movement. However you choose to describe the joint that, without any imageable lesion or any other pathological process, has temporarily ceased to move freely, it still has to be adapted to by the rest of the horse’s functional anatomy in order that the horse can attempt to “keep moving”. What is apparent is that, by degrees, horses with areas of dysfunctional spine become, by degrees, more and more leg-movers.
The horse world is becoming increasingly aware that “leg movers” are not able to perform to their maximal ability. Horses need to be able to use their bodies and limbs synergistically in order to deliver the full free-moving action that they are supposed to achieve. Thus the desired opposite of a “leg mover” is not a “body mover” (that would imply that, by degrees, the legs didn’t work properly and the horse was having to use its body to compensate: a reasonable definition of lameness!).
Instead, we want to convert “legmovers” to more cat-like free-movers.
In the absence of pathology, strengthening the rest of the horse’s musculoskeletal system, whilst supporting the soft tissues that take the lion’s share of the compensatory loading makes a lot of sense and is the mainstay of re-training horses towards better movement (and hopefully fewer secondary problems). Our techniques for doing this are becoming more refined, and frequently more and more successful. All those that are successful will be based (knowingly or not) on maximising the horse’s ability to approach free-movement.
Currently our movement analysis techniques are enjoying rapid advances in terms of both techniques and scientific interpretation and offer exciting glimpses of how we might be able to more effectively recognise both earlier onset pathology and also the non-pathological - yet nonetheless dysfunctional - equine musculoskeletal system.
The goal? Ultimately it has to be the quicker, objective recognition of deficiencies of free-movement. The quicker we can recognise, and do something about these, the quicker the horse can be returned to comfortable and effective normal movement, with the minimum of time for the horse to try to compensate. You can easily argue the welfare basis in terms of minimising discomfort. But it is also likely to lead to a reduction in secondary, compensatory pathologies from degrees of chronic over-loading.
Now that’s where the promotion of free-movement offers the potential for major equine welfare benefit.