From lameness to winning performance

CASE STUDY: by Andrew Poynton FWCF

This case involves an 18-year-old, 17hh skewbald dressage horse.

Condition poor foot balance, intermittent lameness

Symptoms This case, like many others, did not initially have a clear diagnosis at the time of lameness onset. The horse’s performance was inconsistent and varying degrees of lameness blighted him. He was carrying some excess weight. Some lost shoes did not help matters.
This was a veterinary referral; the feet were x-rayed and AP was invited to investigate; what he found was conformation predisposing poor mediolateral foot balance. The horse was low medially with flat feet and with visible chronic laminitic changes in the feet. The x-rays were revealing and invaluable. Subsequently, the horse was diagnosed with equine metabolic syndrome (EMS). As he had not displayed full blown acute laminitic symptoms and had other contributory issues to his inconsistent performance, it was much less obvious until the evidence and magnitude became visible in the hooves.

Stoic nature of this horse masked the severity of his condition
The stoic nature of this horse masked the severity of his condition.

Notably, the soles of the front feet were flat to bulging, with visible sole bruising. It would have been legitimate to treat the horse for flat feet had not the additional laminal white line stretching been evident in the fore and hind feet and, of course, on the x-ray images. The stoic nature of the horse masked the severity of the condition, tempting one to allow more exercise than was healthy. Many other horses in the same condition would have displayed much greater signs of lameness.
In the author’s experience, fitting pads to these feet can restore a level of soundness for a time, but the feet can become even more dependent on them as the soles tend to soften due to the condensation accumulation between pad and sole. Even more pertinently, in this case, being laminitic,
the horse required a greater level of mechanical support than a pad would afford and the sole definitely would not benefit from softening!
If a horse is treated for laminitis but is misdiagnosed and is not suffering from this condition, then no harm comes from the treatment, but if the horse is laminitic and the notion is dismissed or overlooked, and no early support treatment initiated, then much harm can ensue. If in doubt, check it out.

Imprint First front shoes (low temperature melt thermoplastic first aid shoes) Imprint Ultra-Fast Adhesive MMA, Imprint Shoe Freezer, Imprint Hoof Repair (low temperature melt thermoplastic with similar flex as hoof) Imprint Sport front shoes (composite mould on work shoes) steel hind shoes, No 6 nails. Surgical spirit.

All feet were x-rayed prior to AP’s first visit. Both lateromedial (LM) and dorsopalmer (DP) perspectives were taken. Only the LM images are illustrated here as the DP images added little to the narrative, although they were useful for trimming reference.
The LF LM radiograph (Fig 1) revealed no phalangeal rotation but did show capsular flaring and laminal stretching towards the distal border of the hoof. The sole was flat with the pedal bone (P3) low in the foot. In effect, this was vertical displacement, although relatively mild, likely to be so due to the shallow conformation of the feet. Provided the horse was provided with something firm beneath his feet, further sinking was likely to be limited.

Front left lateromedial x-ray.
Fig 1. Left front lateromedial image

Bearing in mind that this horse is 17hh, this may have been his saving grace. As is usually the case, in the early stages of laminitis, external evidence of laminal trauma was minimal other than some historical staining of the sole and wall, but the level of lameness was at its height. At a later date, the magnitude of the condition would be graphically displayed.

Clinically the foot appeared to be out of balance on all planes; the lateral toe flaring while the medial wall was low and crumbling on the quarter. The toe was dumped and squared off. The hooves being non-pigmented revealed bruising to the quarters on all feet. The RF foot was in a similar condition

Right front lateromedial x-ray.
Fig 2. Right front (RF) lateromedial image.
Left hind  lateromedial x-ray.
Fig 3. Left hind (LH) lateromedial image.

The RF radiograph (Fig 2) was clinically similar to the LF. So, when it came to treatment there was no priority as to which foot needed attention first. As always, points of reference were marked on the sole prior to any trimming, marking how far to trim. The x-ray defines bony tissue and horn, but does not highlight vascularity, so when trimming such cases, it is astute to trim with caution as the mark is approached. Gut feelings – experience – should be taken notice of. The integrity of the lower hoof needs to be respected in the early stages of laminitis; it is a fine line to walk, but heeding this may save the patient from unnecessary suffering. Comfort takes priority in these cases.

Radiographs of all four feet showed the left hind (LH) was in the best condition (Fig 3), there was no rotation or sinking of P3 only excess toe both vertically and horizontally, with a mediolateral discrepancy. The feet were due for re-shoeing, so all this foot needed was a decent trim, taking more off the toe and setting the shoe back under the toe to resolve the broken back hoof pastern axis (HPA) and restore more ideal functionality.

Right hind lateromedial x-ray.
Fig 4. Right hind (RH) lateromedial image

Right hind (RH) radiograph (Fig 4). This foot had really run away, an over long toe, divergent laminal wedge and broken back HPA were creating multiple unwanted forces, leverage at the toe and serious overload at the heels as well as increased flexor tension, which in turn creates unhelpful pressure in the navicular region. Drop a line from the centre of articulation of the distal interphalangeal articulation and see the great disparity of ground bearing surface forward of that point relative to what was behind it.

In the vast majority of cases, in an attempt to treat most pathologies, farriers aim to trim the hoof around the orientation of P3 as much as is practically possible, to attain ideal foot balance on all planes, centralised ground bearing and a straight HPA. This is such a case that could get complicated due to the imbalance and complication of laminitis. There will always be exceptions, but the KIS – keep it simple – principle is operative here and proved to be true in this case. The use of reference points such as nails and clips are helpful when deciding how far to trim. The stretched white line at the toe externally was a further indicator of excess needing removal. As with the LH, the RH needed similar treatment only more radical trimming to achieve the same end.

Farriery treatment
The main focus in this case study was the feet, their trimming balancing and recovery, patient management and the materials used to achieve this. Hopefully the reader will find this refreshingly straightforward and simple. Only once the x-rays were taken was laminitis confirmed. The horse was immediately confined to box rest.

First visit, 13 April 2022
Front feet The front shoes had been removed the day before for x-ray purposes. The horse was tender on his feet but stood relatively normally. He was apprehensive and a little sharp, so he was sedated for everyone’s wellbeing.

• The front feet were trimmed and shod taking reference from the x-rays as described above. In addition to the Imprint First Shoe, Imprint Hoof Repair plastic was added to the medial hoof walls to make up for the deficit of natural hoof thereby reattaining lateromedial foot balance.
• The all-important frogplate was augmented extended more toward the apex of the frog, well past the centre of articulation, three-dimensionally moulded to create a ‘frog cradle’.
• The point of breakover was reduced via the rolled toe and the web of the shoe bridging the sole, protecting it from direct impact.
• The shoe can be set under the toe as far as is required, which is apparently a welcome surprise to a number of farriers and vets.
• By maintaining open and clear access to the sole helps keep it dry and hard. In cases where the sole has prolapsed and there is an open wound then access for treatment is there. A snap fit hospital plate can quickly be made if required. • The Imprint First (Aid) shoe is the hospital shoe specifically designed for this purpose, completely adaptable, but not for work, the Imprint Sport shoe, which is durable can and did follow the First shoe as the patient was allowed more freedom.

As is often the case, once a shoe was fitted, then the horse began to relax finding comfort and relief from sole elevation and frog support. So the second shoe is usually easier to fit in such situations. Both feet were treated similarly, bearing the subtleties of trimming relative to the x-rays.

Hind feet As the patient was to be confined to box rest until next visit six weeks later and he had good healthy frogs, the hind shoes were removed and the feet trimmed with reference to the x-rays. Much excess toe can safely be removed, provided there is adequate horn to stand on in the toe quarters.

Initial result
As the patient had been sedated for the treatment he was still partially under the influence of the drugs but coming out enough to be happy to take a walk about; he was surprisingly mobile even when turning in a tight circle, certainly a marked initial improvement. Being a 17hh horse in this condition one would expect a much more fragile patient. Stoic or a high pain threshold, who knows?
When advising owners of aftercare, the author often describes the feet as being delicate like cracked eggs in an attempt to impress on them the fragility of the situation. Unfortunately, many people only take notice of external visual signs until the horse takes a turn for the worse.

Second visit
The patient was moving well and looked comfortable in the Imprint First shoes. In fact, as he looked so well, the owner wanted to get on and begin some light work to help him burn some calories. The front feet were shod with the Imprint Sport shoes and steel hind shoes were nailed on.

Third visit (27 June 2022)
The horse was going so well that on the third visit the possibility of entering a dressage competition was discussed. The previous laminal trauma and sole bruising had then reached the surface in the fore feet appearing quite graphic along with somewhat bulging soles. With this in view the competition aspirations were reined back. The horse was reshod as before and, despite the delicate condition of his feet, he remained completely comfortable.

Fourth visit (25 July 2022)
Shoeing went well, until 6 August when the horse showed lameness in the RF. This was monitored, work eased off and lameness faded out.
Subsequent shoeing’s went fine while the horse was in light work. In January 2023, he was intermittently lame on the RF when turning, although level in a straight line. In February evidence of an historical small infection in the medial heel of the RF was found. Lameness evaporated. As the feet were naturally low medially, to counter this the Imprint sport shoes were rasped around the lateral branch, similar as to a sidebone shoe to compliment footfall and balance. In the earlier days’ extra material was added to the medial branch but as the feet improved it seemed good to reduce the lateral side instead.

As it takes approximately a year to grow a new hoof, to bring the case up to date, the horse was shod last on 9 May 2023 and has entered two dressage competitions and one combined training, in which he won all three! Patience has paid off.
This is clearly good news for a horse of this size and age who has navigated a tricky path and emerged a winning athlete. In the experience of the author this is not an isolated instance. As with many horses dogged by lameness there are commonly a number of issues that need addressing to effect a complete remedy.

This article is from a case study which first appeared in Forge Magazine July 2023. © Andrew Poynton FWCF