Treating arthritis in your horse

It's one of the most common causes of lameness affecting many horses as they age. Vet Matthew Tong explains the latest on this debilitating disease.

New arthritis pic.jpg

The best way to prevent and manage arthritis is to ensure your horse's body is working as efficiently as it can. 

Regular farrier visits to balance the feet and help prevent uneven loading on the joints, keeping your horse at his ideal weight, and a regular, sensible exercise plan will all go a long way to helping your horse's joints work as nature intended. 

It's also a good idea to make sure your horse is always well warmed up before strenuous exercise and well cooled down after to help protect his joints from excess wear and tear.

A good quality joint supplement that boosts your horse's levels of glucosamine and chondroitin (both help to build healthy cartilage) is recommended, and your vet will be able to advise you as to which product to invest in. 

While many people reach for this kind of supplement only when stiffness becomes an issue, it may be more beneficial to give it long-term, from a younger age, especially if your horse is conformationally challenged. For example, if he's pigeon-toed. 

Arthritis: The key facts

  • Arthritis is one of the leading causes of lameness in the UK, and is believed to be responsible for 60% of all cases. 
  • Today's more sophisticated diagnosis tools include nuclear scintigraphy (better known as a bone scan) a radioactive substance that is injected that 'binds' to areas of active bony change within a joint. 
  • These can then be picked up hot spots by a scanner. An MRI scan - which can also be used on the horse's lower leg - can also be used to detect changes in the joint and it's surrounding soft tissue.
  • Riding too fast or hard over poor terrain - be it hard, soft or boggy - can increase the chances of joint trauma and in turn predispose the joint to arthritis. So it's vital you ride with care. 

Kissing spines explained

Kissing spines is a painful condition for those suffering from it. Here, vet David Rutherford from Fellowes Farm Equine Clinic explains more about the condition and the different treatment options available.

The term ‘Kissing spines’ is a term used to describe a condition where the pieces of bone that project upwards from a horse’s back bone (the dorsal spinous processes, or DSPs) become too close together and start to grate on each other, causing pain.

It’s most commonly found in the middle of a horse’s back under the saddle region, but can occur anywhere along the spine. It’s a progressive condition that usually affects horses aged between seven and 14 and is quite common in larger breeds, particularly Thoroughbreds, but rare in ponies.

Bucking can be an early indicator of a problem in your horse's back

Bucking can be an early indicator of a problem in your horse's back

Horses with kissing spines will struggle to perform well under saddle, and show signs of pain in their back – though this discomfort can present itself in different ways. The first thing you may notice is a lack of forward movement, especially in canter. Bucking, refusing jumps or reacting when the girth is tightened or the rider mounts are other signs.

To diagnose kissing spines, the first step is usually to take radiographs of the DSPs. Kissing spines is suspected when the gap between the DSPs narrows and, in some cases, the bones are touching. Often the bony margins will have areas of increased density (which shows as white on an x-ray) and areas where the bone has partly dissolved (black on an x-ray).

In very severe cases the diagnosis may be based on x-rays alone, but this can be problematic as some horses with quite nasty radiographic abnormalities can in fact be completely pain-free in this area. Therefore either bone scanning, or nerve blocking the area and observing an improvement in ridden performance, is usually necessary to confirm the problem.

Can you prevent it?
As kissing spines is a naturally occurring, progressive condition, prevention isn’t possible. There are, however, some things that can be done to help reduce the risk. Experts believe there’s likely to be a genetic component to kissing spines, so breeding from known sufferers should be considered very carefully. In addition, it’s wise to avoid any ridden exercise until a horse is approaching his or her skeletal maturity at three to four years of age. This will give his bones the best chance to develop as they should.

Before you buy a horse, ask your vet to take survey radiographs of his back as part of the pre-purchase exam. Sadly, if a defect is found, this won’t mean the horse will avoid developing kissing spines in the future, but it will at least minimise your risk as a potential buyer.

Finally, bear in mind that the condition is worsened by the action of riding your horse, so symptoms will develop quicker the more work you do with him.

How is it treated?
Once a diagnosis of kissing spines has been confirmed one of three routes can be taken:

1. Medical
While it won’t cure the problem, medical treatment will allow the horse to continue working. Treatment consists of a combination of oral painkillers, anti-inflammatory cortisone injections into the affected part of the back, physiotherapy and altered training methods. This will improve the situation, but rarely resolves it and, as the condition worsens, it becomes less effective.

Surgery can be used to create a larger gap between the impinging bones in cases of Kissing Spines

Surgery can be used to create a larger gap between the impinging bones in cases of Kissing Spines

 2. Surgical treatment
Surgery can be used to create a larger gap between the impinging bones. In some situations wedges of bone are removed, and in others splitting the ligament between the bones is sufficient. Often the procedure is carried out under standing sedation with local anaesthetic, rather than under full general anaesthesia. The exact method of treatment will depend on how severe the impingement is, and on the preferences of surgeon and owner.

3. No treatment
No treatment will ultimately result in retirement or euthanasia. 

To learn more about Fellowes Farm Equine Clinic visit


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Spot the signs of Gastric Ulcers

Zoetis image of ulcer

Equine Gastric Ulceration Syndrome (EGUS) can affect any type of horse or foal in any environment. If your horse is displaying any unusual signs such as poor appetite, body condition and performance, changes in attitude or acute, recurrent colic it’s important to speak to your vet immediately, advises Zoetis vet Dr Wendy Talbot.

Equine Gastric Ulceration Syndrome (EGUS) is a serious and common condition,1,2 with approximately 93%of racehorses, 65% of performance horses, 54% of leisure horses and 50% of foals shown to be affected.2,3,4 The condition is associated with injury to the inner lining of the oesophagus, stomach and upper part of the intestine.2

Horses produce a steady flow of stomach acid to help digestion.1 As a protective mechanism their naturally acidic stomach contents are buffered by alkaline saliva produced in response to regular eating and by the food itself.2 Our domestication of horses, particularly stabling and restriction of grazing, has reduced the time our horses spend eating, resulting in prolonged periods when the stomach is empty, causing reduced production of saliva. In addition feeding grain (rather than fibre) can produce types of acid which contribute to the already acidic environment of the stomach.1

The usual signs of EGUS may include poor appetite, poor body condition, poor performance, changes in attitude and acute and recurrent colic.  In adult horses clinical signs may appear or progress as training intensity, speed and workload increase.2 However, in some horses the signs may be vague. In foals the signs may be very subtle and progress rapidly so it is important to contact your vet immediately if you have any concerns.2

There are many risk factors that may cause your horse or foal to suffer from gastric ulcers. These include stress, intense exercise, a high-grain diet, intermittent feeding, inappropriate management and other illnesses.1,2,4 The only accurate way to definitively diagnose or monitor EGUS is by gastroscopy,1 which involves a vet examining your horse’s oesophagus, stomach and upper part of the intestine using a gastroscope.

Wendy Talbot, vet at Zoetis, said: “EGUS is a serious condition but once diagnosed it can usually be treated very effectively with management changes and orally administered therapy to help the ulcers heal. If you think your horse could be suffering from EGUS you must contact your vet immediately.”

References
1 Bell RJ, et al. Equine gastric ulcer syndrome in adult horses: a review. NZ Vet J 2007; 55 (1): 1-12. 2 Picavet M-Th. EQUINE GASTRIC ULCER SYNDROME. Proceedings of the First European Equine Nutrition & Health Congress. February 9 2002. Antwerp Zoo, Belgium.. 3. Murray MJ, et al. Prevalence of gastric lesions in foals without signs of gastric disease: an endoscopic survey. Equine Vet J 1990; 22(1): 6-8. 4. Sykes BW, et al. European College of Equine Internal Medicine Consensus Statement—Equine Gastric Ulcer Syndrome in Adult Horses. J Vet Intern Med 2015;29:1288–1299

About Zoetis
Zoetis is the leading animal health company, dedicated to supporting its customers and their businesses. Building on more than 60 years of experience in animal health, Zoetis discovers, develops, manufactures and markets veterinary vaccines and medicines, complemented by diagnostic products and genetic tests and supported by a range of services. In 2014, the company generated annual revenue of $4.8 billion. With approximately 10,000 employees worldwide at the beginning of 2015, Zoetis serves veterinarians, livestock producers and people who raise and care for farm and companion animals with sales of its products in 120 countries. For more information, visit www.zoetis.com.

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Common Leg Problems: Tendonitis

See a swelling on your horse’s leg and your first reaction might be to panic - will it take ages to mend, cost me a fortune and potentially affect his future? But don’t panic. With good management, most leg problems can be prevented and early intervention from your vet will more often than not lead to successful treatment.

What is it? 

This is a broad term referring to the inflammation of a tendon. Tendon injuries are one of the most common musculoskeletal problems. The superficial digital flexor tendon (SDFT) is the most frequently affected tendon, with the injury usually occurring at the mid-canon level. Tendonitis can be caused by both intrinsic (strain or displacement) and extrinsic (bruising, penetration, laceration) factors. Intrinsic problems are common in equine athletes, but rare in ponies.


Diagnosis and treatment

In most cases, heat, pain and swelling of the SDFT can be felt over the back of the canon bone. Severe cases will have a ‘bowed’ appearance and may also show over-extension of the fetlock joint when the horse puts his weight on the leg. The degree of lameness is related to the degree of inflammation and not necessarily the extent of the actual tendon damage, so investigation is important. Ultrasonographic examination of the tendons is the best way to confirm the type and extent of the injury. The best time for the first ultrasound scan is between four and seven days after the injury.

The leg should then be scanned at regular intervals to monitor healing. Numerous treatments have been described for tendonitis. During the acute stage (up to three days after injury), cold therapy, support bandages, rest and anti-inflammatories are recommended. There are also a variety of medications for direct administration into the tendon.

Recently, the use of stem cells has received particular interest. These cells are the precursors to all the cells in the body. The benefit of their use in tendon injuries is related to the method of tendon repair. Tendons are unable to regenerate new fibres following injury and instead heal through the formation of scar tissue. Stem cells are stimulated to become new tendon cells (tenocytes), which means the tendon heals through regeneration of normal fibres instead of scar tissue. Scar tissue is prone to injury again, so the use of stem cells could help the horse stay sound. However, the mainstay of treatment for tendonitis remains the controlled return to exercise. The timing and intensity of this should be dictated by the ultrasonographic appearance of the affected tendon.


Prevention

Appropriate early conditioning of young horses will improve the quality of the growing tendon tissue, making them more resistant to subsequent injury. Careful attention should also be paid to speed, ground surface, fatigue, shoeing and weight of rider. Protective boots will help prevent extrinsic causes of tendonitis.

Navicular Syndrome

An MRI image - Magnetic resonance imaging (MRI) allow vets to take a closer, detailed look at all the structures in the foot - bone, cartilage, tendons and ligaments.  

An MRI image - Magnetic resonance imaging (MRI) allow vets to take a closer, detailed look at all the structures in the foot - bone, cartilage, tendons and ligaments.  

Navicular syndrome is a debilitating condition responsible for over a third of chronic lameness in horses. If your horse is diagnosed with the condition it must feel like a crushing blow, but do not despair! Nowadays there’s so much you can do to manage a horse with navicular syndrome and research into this troublesome condition is progressing at a rate of knots. 

The more we understand about the underlying processes, the more able we will be to treat navicular successfully, giving afflicted horses the best quality of life possible.  Here is all the information you need to fight the battle, along with some encouraging advice from owners with first-hand knowledge of the condition.

Here our expert, vet Charlie Tomlison breaks the condition down.

What is navicular syndrome?

Navicular is not a single disease per se, but more of a “syndrome” where multiple structures may be implicated. The navicular bone is a small boat-shaped bone, sitting at the back of the foot and tucked behind the larger pedal bone.  It’s held in place by a number of ligaments. The navicular bursa is a sac filled with lubricating synovial fluid positioned at the back of the bone to cushion the deep digital flexor tendon as it passes over the navicular bone. Pain associated with navicular syndrome can come from damage to any of these structures supporting the navicular bone, as well as direct damage to the bone itself. Historically, navicular disease was attributed to interruption to the blood supply to the navicular bone, “the vascular theory”.  This has gone out of favour as a major factor in navicular syndrome but treatments geared towards restoring the blood flow do have some effect, so opinion is still divided. The navicular bone takes a lot of biomechanical strain when the horse moves.  As the deep digital flexor muscle contracts, the tendon tightens and pushes on the navicular bone.  To help prevent damage to the tendon or navicular bone, a thick layer of fibrous cartilage protects the bone, and this is may be worn down in cases of navicular syndrome.

To make some generalisations, it’s more commonly found in horses with a certain foot conformation - overlong toes and collapsed heels.  There is believed to be a genetic component as navicular syndrome is more common in certain breeds such as warmbloods, thoroughbreds and quarter horses.  It rarely affects ponies.   A susceptible conformation subjected to repetitive concussion can lead to a degenerative processs within the foot.

The average age for a horse to develop signs of navicular disease is 7-11 years, and this perhaps reflects the degenerative nature of the problem caused by wear and tear.  However, it can be seen in horses as young as 3 years old occasionally.

Symptoms

Navicular syndrome can creep up on owners unawares.  It may start as an intermittent low-level lameness that resolves quickly with a couple of days off.  In the early stages, some horses may “warm out” of the lameness, appearing stiff as they leave the stable, then improving with a bit of exercise. 

The lameness is most commonly seen in the front feet.  Usually both front feet are affected, which can sometimes make it difficult for the owner to identify.   This is because, if both feet are affected equally, there will be no obvious head-nod when the horse is trotted up in a straight line.  The stride may look short and choppy.  Lameness may be more noticeable if lunged on a circle, however, as the inside leg takes a greater strain. In some cases, the horse may stumble frequently or point one foot.

A keen eye may notice that the horse subtly puts its toe to the ground slightly before the heel lands when walked on a flat surface and viewed from the side.   This “toe-heel” action occurs because horses with navicular syndrome feel pain in their heel region.

Precise diagnosis is based on the characteristic signs, together with a lameness work-up by your vet.  Your vet may employ a number of techniques in locating the source of pain, including injecting local anaesthetic around nerves supplying the foot or into joints within the foot.  These nerve blocks can narrow down the region the pain is coming from, but recent research has shown that they must be interpreted with care as the anaesthetic can diffuse and affect areas other than those it was intended for.

If navicular syndrome is suspected, X-rays can be taken of the foot.  These focus on two things: 

The shape and balance of the foot,  i.e. how the external appearance of the hoof relates to the internal positioning of the bones within the hoof.  Here vets look at the angles of various structures in the foot to determine what biomechanical forces are applied to the hoof. 
Secondly, the appearance of the navicular bone itself is evaluated.  A number of changes seen on the bone, such as new bone formation, or loss of bone density, can indicate potential navicular syndrome.  It is worth noting, however, that some horses have x-ray changes on their navicular bones and aren’t lame, whilst others have proven navicular syndrome with no evidence of this on x-ray.

Diagnosis

Diagnostic techniques taken from human medicine have been adapted for horses.  This has taken the diagnosis of navicular syndrome to a new dimension. Magnetic resonance imaging (MRI) and Computed Tomography (CT) allow the vet to take a closer, detailed look at ALL the structures in the foot - bone, cartilage, tendons and ligaments.  This has enabled vets to diagnose soft-tissue injuries previously unseen on X-ray. 

MRI scanning is restricted to referral hospitals.  Conditions that may once have been put down to navicular disease can now be more accurately diagnosed, such as fraying of the deep digital flexor tendon within the hoof or damage to the supporting ligaments of the navicular bone. 

These ways of viewing the foot are very useful but also expensive.  Some insurance companies don’t cover their cost fully, so it’s worth bearing this in mind beforehand.

Prevention

In many cases it can be hard to see how you prevent a condition from developing when so many factors contribute to it!   However, some simple rules do apply.  Good, regular routine farriery every 4-6 weeks will help reduce the load on the heels and over the navicular bone.  

If your horse historically “feels” the ground, it is common sense to avoid riding at speed or jumping on hard ground. The repetitive concussion of riding on hard ground is inflicted on the heels and navicular region and can be enough to encourage the onset of this degenerative condition.  Avoid tight circle work unless on a soft, level surface.

Be sensible if the ground is unsuitable.  If you turn up at a competition and the going is too hard, be wise enough to put your horse back in the lorry, no matter how far you’ve driven, and curse the good weather on the way home!

Treatment

Treatment options for navicular sydrome have come a long way.  Firstly, the treatment should be geared towards the actual structures identified as involved in each individual case.   For example, a soft tissue injury may require an extended period of box rest  (over 6 months in some cases).

Corrective farriery is a vital part of, if not the main piece, in the treatment jigsaw!  Teamwork between you, your vet and your farrier can assist in keeping your horse sound and comfortable. 

The aim is to re-establish the best foot shape possible to cope with the demands of work and to fine-tune the forces placed on the foot to avoid over-loading the vulnerable areas, namely the rear third of the hoof. The feet should never be allowed to grow overlong and so make a date in your diary for shoeing every 4-6 weeks, The foot should be balanced from side to side, the toes shortened and good heel support provided.  This may take the form of a rolled toe or four point shoe, bar shoes or 10° heel wedges.  Some farriers like to use silicon pads for their anti-concussive effects.

Careful use of oral anti-inflammatories may help, such as phenylbutazone (bute).  It’s important not to make the horse so comfortable that it worsens an existing injury.

Vets often inject an anti-inflammatory, such as steroid, directly into either the coffin joint or the navicular bursa.  Injecting into the navicular bursa is the trickier but more effective option. In one study, 60% of horses were still sound after 2 months following bursa injection, compared to 34% that had their coffin joints medicated.

A newer treatment to the UK is the anti-arthritic drug, tiludronate, (Tildren™). It helps to switch off cells involved in arthritic processes.  It is given as an intravenous drip and has been quite effective in treating some forms of navicular disease where bony remodelling is a feature.  

In some cases, the vasodilator, isoxuprine has been used successfully on the basis of the restoring good blood flow to the feet, part of the vascular theory of navicular disease.

As a last resort, some owners opt for neurectomy (de-nerving operation).  This is a surgical procedure to numb the foot by cutting the nerves that supply it.  It is often used as a last resort as there are many risky consequences associated with de-nerving, such as dangerous stumbling or development of severe foot abscesses.  Sometimes the nerve grows back or forms a painful lump called a neuroma.  Many governing bodies, such as the FEI, do not allow de-nerved horses to compete.  Despite this, for some horses and owners it proves to be a valid option and they continue a happy, pain-free life for many years. 

 

More about our expert

Charlie Tomlinson (Briggs) is an equine vet working for Hale Equine Vets in Wiltshire.  She’s worked at various large equine referral centres and is a keen horse woman having owned and competed horses all her life. Her main areas of interest are equine orthopaedics and breeding. Find out more at www.haleveterinaryhospital.co.uk/equine