Addressing a straightness issue means teasing out cause and effect, explains Dr Liz Barr MRCVS
Applying the term “crooked” to a horse may cover a number of conditions, from more obvious developmental and congenital abnormalities, through lameness issues, to subtle nuances of training and difficulties with achieving straightness in certain dressage movements.
In its most severe form, crookedness is recognised at birth or in the first few months of life, as either crooked limbs – known as angular or flexural limb deformities – or a spinal deformity.
Angular and flexural limb deformities normally affect the fetlocks, carpus (knee) and hocks and should be addressed early in the foal’s life – before six weeks of age for fetlocks and six months of age for knees and hocks. Treatment consists of changes in feeding and management along with appropriate farriery or foot trimming, or a medical approach such as casting or splinting of the limbs. In certain cases, surgery may be necessary.
A foal may also be born with a spinal deformity. Lordosis is the term for excessive downward curvature, or “sway back” conformation; kyphosis refers to excessive upward curvature, at times termed a “roach back”, while scoliosis means excessive sideways curvature of the neck or back.
Although severe deformities, particularly scoliosis of the neck, are often not compatible with life, mild conformational defects are common. There is a belief that lordosis, kyphosis and scoliosis can be caused by abnormal positioning of the foal in the womb, but there is no real way of proving this theory. Many horses in their twenties and thirties develop sway back conformation as a normal ageing change.
Natural bend
Some horses are crooked in that they have a “good” or “bad” rein and prefer to bend one way more than the other. This may be due to the current level of training or as a result of poor schooling.
An inclination to bend one way has also been put down to the position of the foal in the womb, or because horses are intrinsically left or right “handed” in the same way humans are. Again, this would be impossible to prove. It is also possible that foals start off straight but develop a preference for bending one way over the other as a result of early training and groundwork, which is performed traditionally and predominantly from the near (or left-hand) side.
A rider can have an impact on a horse’s crookedness and bend preference. Many riders are crooked to some extent, perhaps placing more weight through one hip or keeping an uneven rein contact, which inadvertently results in more bend one way.
Poor saddle fit and saddle slip can also make a horse move crookedly. Saddle slip, in turn, has been shown to be associated with hindlimb lameness, so this must also be considered as a possible underlying issue.
As well as moving crookedly through the spine with uneven bend when ridden, a horse may move crookedly through the limbs. A horse with hindlimb lameness will often compensate by moving on three tracks – meaning the hindlimbs do not follow in the same path as the forelimbs as they should, but instead move on a separate track. Forelimb lameness can also result in crookedness. Horses with foot pain tend not to bend correctly when lunged in a circle, for example, and may look to the outside.
In short, some sound horses will move crookedly or on the wrong bend as a result of problems with conformation, schooling, saddle fit or rider influence. Some lame horses will compensate for pain associated with the limbs by altering their way of going, such that they move on three tracks or only bend one way.
Complex cases
In order to tease out why a horse is moving crookedly, the usual, logical approach to lameness examination applies. The horse should be walked and trotted in a straight line, before flexion tests are performed. He should then be evaluated when lunged on soft and hard surfaces, on both reins and, unless severe lameness is evident, viewed under saddle.
A horse compensating for distal (lower) limb orthopaedic pain, which results in a crooked way of going, will have mild lameness in either both hindlimbs, both forelimbs or all four limbs. In addition, he may have secondary back or sacroiliac pain. These lamenesses can be complex, so performing diagnostic analgesia (commonly known as nerve and joint blocks) can be time consuming.
Despite their complexity, these cases are often very rewarding from a veterinary surgeon’s point of view. The transformation in the horse’s way of going after successful blocking can be impressive. After pinpointing the areas of pain and imaging the relevant regions, a diagnosis can be reached with the aim of treating the problem.
There may be no obvious lameness or evidence of primary back pain or sacroiliac pain upon musculoskeletal examination, so other causes of crookedness should be considered, such as a poorly fitting saddle or rider influence.
The use of a mechanical horse or dressage simulator can pinpoint any asymmetries or balance problems in rider position. It is also worth assessing the horse’s level of training and ascertaining whether this is a schooling issue that will improve with exercise. Seeing the horse ridden by someone else may be revealing.
After being ridden in a crooked fashion for some time, there will be changes in a horse’s muscles and ligaments. Physiotherapy can be extremely beneficial. The soft tissues on the inside of the preferred bend are likely to be tighter and shorter than the muscles on the outside, so appropriate straightening exercises, along with stretches and massage, can help enormously.
Where a horse is crooked as a result of bony spinal deformity, the bone cannot be straightened. Physiotherapy to ease any secondary soft tissue pain may still help.
Mild spinal deformities do not necessarily impact on a horse’s athletic potential, depending on the discipline and the level at which he competes. Attempting to “straighten out” an otherwise sound and successful older showjumper, who has always preferred to bend one way, may even result in more problems in the long run.
However, dressage horses are encouraged to work as straight as possible from the very outset of training. If a dressage horse who has previously worked in a correct fashion suddenly appears crooked, then the reasons must obviously be sought and corrected.
A sideways look
We habitually handle and mount our horses from the left-hand side, but is there more to this than merely tradition?
Studies suggest that horses may be happier with this arrangement. Research shows that foals and their dams prefer looking at each other with their left eye and, in most situations, will choose to keep each other in their left field of vision. Adult horses, when studied, tended to favour keeping people in their left line of sight in many situations – regardless of the side from which they’d been trained.
While there is more to be learnt about equine “laterality” (the dominance of one side of the body or brain), we do know that straightness is best for soundness. By establishing good handling and schooling habits at the earliest opportunity – working evenly on both reins and the rider ironing out their own physical issues – a horse is less likely to become one-sided.
Where injury does cause crookedness or when a horse’s conformation creates extra challenges, a multi-pronged approach involving the vet, farrier and physio is often most effective in setting him on the right track.
Ref Horse & Hound; 16 July 2020
