Arthritis

Horses Common Treatments

What is arthritis?

Arthritis literally means inflammation of a joint. It can be traumatic in origin affecting one joint or most commonly develops slowly over time due to wear and tear and affects multiple joints. There is a scale of disease from inflammation of the synovial fluid and joint capsule only known as synovitis, through to involving cartilage damage and then progressing to involving the bone then termed osteoarthritis. Arthritis is most commonly bilateral and symmetrical e.g. involving both hocks. There is a condition in young horses called juvenile arthritis which may have an inherited genetic component, but the most common form is in adult horses and is due to wear and tear. Arthritis is one of the most common conditions seen in equine veterinary practice and is responsible for a large amount of loss of use in ridden horses.

Symptoms

Horses may demonstrate one or more of the following symptoms:

Lameness
Poor performance
Back and/or neck pain
Difficulty in canter – disunited, incorrect strike off
Swollen joints
Fidgety or struggling for the farrier when limbs flexed or when nailing on
Stiff coming out of the stable
Limb filling when stabled
Takes time to warm up when ridden

Diagnosis

A thorough history taking and physical examination is a key starting point. The vet will then observe the horse in walk and trot in a straight line and perform flexion tests to test various joints further. Observing the horse on the lunge on both hard and soft surfaces also reveals more information. If there is a suspicion of joint pain then further diagnostics will likely be indicated. This can involve nerve blocks where different regions of the limb are made numb to localise the source of discomfort and will also include x-rays with or without ultrasound scans. In some circumstances referral for higher level diagnostics is needed such as for MRI scans or nuclear scintigraphy scans.

Treatment Options

There is a wealth of treatment options available for arthritis in horses and the right choice is individual for each owner and horse.

Joint injections

Injecting medication directly into the affected joints provides targeted pain relief and positive effects on the joints themselves and is often the most reliable way of achieving soundness. We have options of what product to inject as follows:

Steroids

Steroids are potent anti-inflammatory drugs which reduce pain and inflammation due to joint disease. When injected directly where they are needed, they have maximum effect and there is minimal systemic absorption reducing side effects around the body. Steroids start acting very quickly (within days) however their duration of action is variable. On average a horse who responds well would remain sound for 3-6 months.

Side effects with steroid joint injections include infection and laminitis. Infection is uncommon and the risk of this is reduced by the strict sterile approach to the procedure and careful aftercare. Laminitis from steroid joint injections is very rare and is usually only seen in high-risk horses. A risk assessment can be made prior to this treatment involving a physical assessment and possibly blood tests for cushings and/or equine metabolic syndrome.

Steroids are prohibited under FEI competition rules therefore please discuss if this is applicable to you and your horse and we can advise on appropriate withdrawal periods prior to future competition.

Hyaluronic acid (HA)

HA can be injected into joints alongside steroid or on its own. It provides anti-inflammatory effects and lubricates the joints whilst topping up the body’s natural HA levels which are used to support healthy synovial fluid, cartilage and joint capsule. There can be a joint flare reaction if used without steroid so it is common for a short course of anti-inflammatories to be given at the time of injection.

Arthramid

Arthramid is a polyacrylamide hydrogel which when injected into a joint adheres to the synovial lining reducing the effects of inflammation and forming a cushion in the joint. It forms its cushion and begins to take its effects over the 14 days following injection and the full effect is seen within 4 weeks after injection in most cases. Due to its nature of action it shows potential as a long-term solution to joint disease and is thought to elicit positive effects for multiple years in the joint.

As with any joint injection there is a risk of infection which is minimised by strict sterile injection technique and careful aftercare. There have been no reports of systemic side effects or allergic reaction however mild self-resolving swelling or joint flare at injection site is occasionally reported.

Stem Cells

A mesenchymal stem cell product made from umbilical cord tissue is now available as a ready to inject preparation making stem cells more readily available. Stem cells elicit positive effects in the joint via a natural anti-inflammatory effect, inhibition of cartilage breakdown and providing a basis for repair of damage. The clinical effect is seen approximately 4 -5 weeks post injection, and it has potential to have longstanding benefits.

Systemic Treatments

Anti-inflammatory Medications

Either a course or long-term use of systemic pain relief medications can be highly effective in managing arthritic horses. The benefits include effective reduction in pain and inflammation, a horse-wide effect which is helpful if multiple joints and multiple limbs are affected, and it is non-invasive as the medication is given in feed. Examples of drugs used for this include phenylbutazone (Equipalazone/Chanazone), suxibuzone (Danilon), meloxicam (Metacam/Inflacam/Rheumocam) and firocoxib (EquiOxx).

Cartrophen/Osteopen

A course of intramuscular injections containing pentosan polysulphate which provides pain relief and supports repair of damaged cartilage.

Tildren/Osphos

A type of medication called bisphosphonate administered via a drip in the case of tildren or intramuscular injection if using osphos. This drug slows down resorption of bone and is particularly useful in the long-term treatment of hock arthritis and navicular disease as bone resorption is a feature of these conditions.

Rehabilitation

A whole horse approach is essential in managing arthritis.

Farriery

Make sure your farrier is always kept updated if a diagnosis of arthritis is made (your vet can do this). Optimal foot balance is essential for ensuring the forces through the joints are kept equal and do not predispose to further joint inflammation and your farrier may choose to alter the shoeing cycle or use a different shoe for supporting certain conditions.

Physiotherapy

Regular physiotherapy will keep the secondary muscular compensation maintained, relieve any muscular discomfort and provide targeted exercises to help support the horse moving forward.

Acupuncture

An additional therapy which can provide pain relief and relieve secondary muscle tension.

Exercise

Arthritic horses often benefit from regular low intensity exercise to keep them supple, improve synovial fluid quality and prevent stiffness. Often after treatment we aim to return horses to their previous level of work although sometimes in more severe cases the workload may need to be altered. For example, a horse may be better to only be jumped on a surface opposed to firm ground or may happily hack for years without medication but would struggle to do more. In the short-term post treatment rehabilitation, there should also be a focus on building muscular strength to support the inflamed joints and reduce recurrence of lameness. This will often involve pole work, hacking, hill work and possibly water treadmill.

Saddle fitting

Optimal saddle fit is essential and regular checks are required to accommodate for any changes through the horse’s body which may be more likely in arthritic horses.

Turnout

Horses with arthritis tend to do better with more turnout opposed to more stabling. Offering as much turnout as possible and considering 24/7 turnout can be helpful in managing these horses.