Prevention and Management of Arthritis

It’s a cold winter morning. The kind where every breath comes out like a small cloud as the water vapor crystallizes in the frosty air. You tromp off to the barn, searching for your old friend to kick off an early ride through the fields. You unlatch his door, lead rope in hand as you bring him into the grooming stall to tack up, but today his steps are a little unsteady and as you look down you see his legs are swollen. Too sore to ride today, and your dreams of a winter morning ride melt away like the icicles dripping off the eaves of your stable.

Arthritis is a common villain for riders and horses everywhere; stealing the best riding years of your equine companion’s life. But it doesn’t have to be this way.

If you know what to look for you can prevent arthritis from being a permanent part of your horse’s life, and if it’s already too late for that, you can take steps to reduce the number of days they spend in pain.

To do that, first we must understand what it is we’re up against.

What is Arthritis?

There are two definitions worth knowing. One because it is the correct definition and the second because it is the commonly misconstrued definition. Let’s first start with the true definition.

Arthritis is inflammation of one or more joints.

Simple enough. So where does the confusion lie?

In popular discussion, arthritis has come to be known as the skeletal condition that can be recognized via x-ray as bone changes within the joint. However, once these changes can be seen in x-rays, it’s already too late. The condition has become permanent (or chronic as we say clinically), and can no longer be cured, only managed.

Before these bone changes occur, arthritis is initially a disease of the joint soft tissues. This is followed by cartilages damage before finally, bone deterioration.

Earlier recognition of joint inflammation and its causes can prevent the development of bone changes leading to chronic arthritis.

Arthritis in the Body

The horse’s skeleton has 205 bones that are connected by joints.

These bones are held together by ligaments and tendons.

Ligaments hold bones to bones.

Tendons hold bones to muscles.

Within these joints are capsules that contain synovial fluids which act as lubricants for the joints.

As a whole, the skeletal system is its own type of organic machine; requiring a delicate balance to run safely and effectively. Each of these parts works together for the functionality of the whole. When one or more components fall out of balance, it can cause pain or in critical cases, cascading failures across the system like broken bones, ruptured tendons, torn ligaments, and other injuries.

Arthritis is a form of imbalance within the system. So how do we recognize it early before it becomes more painful or more dangerous?

Arthritis symptoms include:

• Lameness

• Swollen joints

• Pain on flexion

Recognizing these symptoms is the first part of preventing a chronic condition. Let’s deepen our understanding as we learn what can be done after recognition.

Mechanisms of Arthritis

1. Synovial lining secretes inflammatory products and excess fluid.

2. Excess fluid stretches joint, causing pain.

3. Inflammatory products damage cartilage causing more pain.

4. Bone spurs or osteophytes form to try and stabilize the joint.

Prevention of Arthritis

There are 4 things to consider in the prevention of arthritis.

1. Conformation

2. Shoeing

3. Exercise

4. Supplements

Conformation

There are certain attributes that can determine a horse’s athletic potential beyond their own individual spirit. These lie in the design of its physical form, what we refer to as conformation. Rather than aesthetic preference, conformation can be a critical determinant of a horse’s future soundness and is something all riders should be aware of when purchasing or searching for a new equine partner.

Specifically, we are going to focus on 4 major faults that should be considered when purchasing an equine athlete.

1. Toed In or Toed Out

2. Back At The Knee

3. Straight Hind Limb

4. Long Back

Starting from the front of the horse and moving to the rear.

Forelimbs

The horse’s forelimbs absorb the majority of the concussion and tension in motion as 65% of the horse’s weight is on the forelimbs. Conformational flaws in the forelimbs are under the pressure of considerable forces throughout the horse’s career.

Toed in conformation adds compression on the inside of the limb and tension on the outside. This deviation can usually be observed starting from the fetlock. Over time, athletic use and added forces over-stress the supporting ligaments, overloading both bone and cartilage.

Back at the knee adds tension to the flexor tendons and ligaments and compression to the front of the carpus and fetlock. The excess forces can lead to soft tissue injury and arthritic joint changes over time.

Hindlimbs

Straight hind limb adds load to the hip, stifle, hock, hind suspensory ligament, and fetlock. This can lead to hock arthritis and other soft tissue injuries like that of the suspensory ligament.

Long back increases flexion and extension of the spine. Think of what happens with a common lever when you increase its length. You gain additional leverage and are able to exert more force on the object you’re affecting. The same thing happens here, where all of the forces exerted on this horse’s spine are magnified, requiring more mass to stabilize, which is often not present. A ligament injury often precedes an arthritic spine.

Conformational Truths

There is no horse with perfect conformation. Taking that in mind, what do we do to help prevent arthritis in horses who have these faults?

We are mindful, and pay extra attention to their weak spots with some basic care and prevention principles that apply to all equine athletes.

Shoeing to Prevent Arthritis

The farrier is a good place to start when taking steps to prevent arthritis. These are principles that should be followed regardless of the risk of arthritis and given additional attention when the risk of arthritis is present.

Provide good toe and heel support.

Exercise to Prevent Arthritis

For more in-depth information about exercise fatigue, I explore the topic a bit deeper in my article, Prevention of Tendon and Ligament Injuries.

When exercising, it is critical to consider the factors of fatigue and overuse. Once you’ve crossed the threshold of exhaustion, you have already put your horse at risk for the conditions that lead to arthritis.

This is especially common for the weekend warrior; the rider who works a full-time job during the week and tries to make up for it with more strenuous riding during the weekend.

Muscle fatigue decreases joint support by soft tissues and all it takes is a small misstep to cause an injury.

Difficult cross-training — where the horse is worked harder than necessary for its competitive goals — is another source of these risks. This can also come in the form of drilling a task repetitively, causing the same continuous strain on your horse’s legs without relief. Suddenly schooling the same dressage test or reining exercise five or six times in a row doesn’t seem so innocent.

Make each training session count, and know that expanding your horse’s capacity doesn’t necessarily require pushing their limits every day.

Best Practices

• Exercise should be regular, consisting of 4-5 days each week.

• Consider your horse’s age, athletic goals, and fitness level.

• Trot work is the key component to safely increasing baseline fitness.

• Always utilize the walk warm-up. Take 15-20 minutes walking before each session to lubricate the joints and stretch the tendons and ligaments.

Specific Exercises

To increase your horse’s overall neck and back strength you can incorporate these exercises into your program.

• Walk to canter transitions

• Collection and extension at all gaits

• Bending exercises

  • Spiral downs

  • Serpentines

Supplements to Prevent Arthritis

There is an increasing amount of evidence showing that glucosamine, when given at a dose of at least 10,000mgs for a 1,000lb horse, helps to protect cartilage from inflammatory products and provides building blocks for the repair of micro-trauma. More on that later.

If your horse has a warm, painful and/or swollen joint:

• Recognize that injury to the supporting structures may be the cause.

• Even if radiographs are normal, tendons, ligaments and joint capsule may be affected.

Treatment of Equine Arthritis

Treatment of equine arthritis is better-called management of equine arthritis because it is an ongoing task that if not undertaken early enough in the process will become a lifelong part of your horse’s care. Catching it early requires thinking beyond the x-ray as we need to examine the soft tissue before any bone changes occur.

Ultrasound Examination

This is how we prevent arthritis from becoming lifelong.

While x-ray is best for examining skeletal structures, it falls short in the examination of soft tissues. This is where the value of ultrasound examinations really shines.

An ultrasound will detect any damage to the soft tissues, providing a diagnostic path towards the treatment of arthritis before it becomes a chronic condition.

Equine Arthritis Management Goals

Arthritis — an inflammation of one or more joints — causes pain at first, then begins to deteriorate both the cartilage and surrounding bone. The management of arthritis follows a parallel route in its treatment.

Before we talk through approach, let’s define the two types of drugs that will be discussed.

SMOAD noun

Symptom-Modifying Osteoarthritis Drug

(1) A drug that relieves the symptoms of osteoarthritis.

DMOAD noun

Disease-Modifying Osteoarthritis Drug.

(1) A drug that inhibits or reverses the progression of osteoarthritis.

Definitions in hand, here are the two major phases of equine arthritis management.

1. Reduce pain (SMOAD)

2. Minimize and slow further deterioration of cartilage and bone. (DMOAD)

Optimum Treatment

When evaluating the treatment options, we consider four factors.

1. Safety

2. Effectiveness

3. Invasiveness (least is best)

4. Cost

Let’s review our options.

Non-Steroidal Anti-Inflammatory Drugs

In humans, this is the classification that Aspirin and Ibuprofen fall under. For horses, here are some of the common medications. These would all be considered SMOADs.

• Phenylbutazone [oral]

• Banamine [injectable]

• Ketoprofen

• Carprofen (Rimadyl)

• Equioxx

• Surpass Cream [topical]

Surpass Cream

Safety: A 
Effectiveness: A+
Invasiveness: A+
Cost: C 

Surpass is a unique contender among this list as it is applied topically. It’s relatively safe, non-invasive, and there is minimal systemic effect, which means that it only works on the area that it is applied to. This is best when there is only one joint involved. It is effective as both a SMOAD and DMOAD, so it has the potential to be a complete solution. The only downside is that it is somewhat expensive.

Steroid

Safety: D 
Effectiveness: A+
Invasiveness: C 
Cost: (TBD)

Steroids are given intra-articular (IA) and are the ultimate anti-inflammatory agent. This doesn’t come without strings attached, as they have substantial side effects. Most notably, they decrease cartilage metabolism; thinning or directly abrading cartilage. This is detrimental to long-term healing.

Adequan

Safety: ??
Effectiveness: ??
Invasiveness: ??
Cost: ??

Need more info from Carol.

Laser Therapy

Safety: ??
Effectiveness: ??
Invasiveness: A+
Cost: ??

Laser therapy is good for acute soft tissue inflammation, but as of today little is known about healing effects or long-term use. Additionally, an analysis in 2015 did not support the use of laser to treat arthritis.*

*Reference: Effectiveness of low-level laser therapy in patients with knee osteoarthritis…

Extra Corporeal Shock Wave (ECSW)

Safety: ??
Effectiveness: ??
Invasiveness: ??
Cost: ??

In laymen’s terms, this is basically super ultrasound. More clinically, it’s called modified lithotripsy.

How It Works
It uses a sequence of single sonic pulses characterized by high peak pressure (100 MPa), a fast rise in pressure (<10ns) and a short lifecycle (10 micros) that are conveyed by an appropriate generator to a specific target area at an energy density ranging from 0.03 to 0.11 mJ/mm².

ECSW can be effective for pain relief for approximately 4+ days.

An important consideration for equine athletes is that this process will disrupt collagen for 6 weeks. The disruption occurs in both injured and normal tendons and ligaments. This means during the 6-week period the joint is particularly vulnerable to stress and exercise will need to be limited until the end of the 6 weeks. After that period, repair begins to be up-regulated (rapidly improves).

The FEI and Racing Jurisdiction of the United States have both implemented regulations regarding specific withdrawal times before competition to protect equine athletes who have undergone ECSW.

Regenerative Therapy

There are some modalities that utilize regenerative approaches to treatment. In certain circumstances, these may greatly enhance the rate or quality of healing of some tissues. These all have areas of concern to go with their narrow, but effective, scope of benefits.

IRAP

Safety: ??
Effectiveness: ??
Invasiveness: ??
Cost: ??

This modality uses a specific protein (IL1-RA) which then blocks IL-1 (interleukin) from binding to the surface of the joint. IL-1 is a part of a horse’s natural response to joint damage, but can actually be counterproductive during the healing process as it causes additional inflammation. By preventing IL-1 from activating, inflammation is reduced, alleviating pain and lameness.

The process involves drawing blood from the horse, where it then goes to a lab where it is used to create a conditioned autologous serum (containing the IL1-RA protein) before being injected back into the horse intra-articular.

PRP

Safety: ??
Effectiveness: ??
Invasiveness: ??
Cost: ??

PRP stands for Platelet-Rich Plasma. Similar to IRAP, during this treatment process, blood is withdrawn and conditioned in a lab to concentrate the platelets containing multiple growth factors. This is then reinjected back into the horse intra-articular, where those platelets go to work releasing all their growth factors and overall stimulate regenerative healing within the joint.

Stem Cell Therapy

Safety: ??
Effectiveness: ??
Invasiveness: ??
Cost: ??

Stem cell therapy holds a lot of promise for cartilage repair, yet leaves many basic questions unanswered about its use. These cells can be derived from a number of different areas. Within the horse in question are bone marrow and fat-derived stem cells, yet these can also be derived from other horses.

The stem cells, wherever they are derived from, are injected directly into the site of the joint damage. Once inside, the stem cells go to work coordinating the other nearby cells to do the work of regenerative repair. The cells live for 7 days while performing their work.

Scientific trials have shown variable results for arthritis therapy.

It is also concerning that all current equine research into stem cells is being performed by shareholders in stem cell production companies.

Limitations of Intra-Articular Injections

In general, all of these therapies that are supplied via IA injection have the limitation of only affecting the area of injection, when most horses have more than one affected joint. A systemic approach that can treat all of the joints affected simultaneously is preferable. This brings us back to oral joint supplements.

Supplements to Treat Equine Arthritis

Choosing a supplement that is based on research is the best way to make sure that you are giving your horse the best possible product and also making a responsible investment of your horse-care budget. The two most researched and clinically proven supplements are:

• Glucosamine

• Hyaluronic acid

We will also discuss another common supplement that is less clinically proven, but still in popular use today:

• Chondroitin sulfate

How Glucosamine Works

Glucosamine performs multiple roles in the protection of joint health.

• Blocks IL1 (Interleukin) inflammatory products in cartilage and synovium.

Remember that arthritis is caused by inflammation. Blocking the causes of inflammation is one way to prevent and treat arthritis in your horse.

• Provides both material and stimulation for proteoglycan synthesis.

This means that glucosamine is the building block for some important things that go into a healthy joint. Proteoglycans help the cartilage in your joints to stay strong. When inflammation occurs in the joint, the proteoglycans get degraded, which can lead to a feedback loop spinning straight towards arthritis.

Not only do proteoglycans get degraded by inflammation, but they are also reduced by steroids. Steroids are often given to reduce inflammation in the first place, but without something to reinforce the proteoglycans, they can lead to further inflammation down the road.

• Protects cartilage from a decrease of proteoglycans production caused by steroids.

With glucosamine in the system, steroids can be safely administered without fear of degrading cartilage.

• Increases bone metabolism to counteract bone resorption similarly to bisphosphonates like OSPhos or Tildren.

Bone resorption is this nasty effect where your horse’s bones break down into their bloodstream, weakening their skeletal system. Glucosamine is shown to prevent that by helping the bones get the resources they need from the body to stay strong and healthy.

Why Glucosamine is an Effective Choice

Glucosamine has been shown to be effective at an oral dosage of 1000mgs per 100lbs horse weight daily. This means that the lovely thoroughbred on your farm only needs about 11-12 grams per day.

The side effects have been shown to be similar to placebo in all clinical trials. This is a scientific way of saying nearly non-existent side effects.

It’s very cost-effective.

How Hyaluronic Acid Works

Joint fluid is largely crafted from hyaluronic acid and is what provides that critical lubrication to keep joints functioning efficiently. This goes a long way to prevent joint pain in your horse.

It also has a self-generated rapid anti-inflammatory response. This means it is one more preventative measure against inflammation and arthritis.

In veterinary operations, it has been shown to be effective at reducing post-operative stifle effusion (swelling) in 24 hours at 10mgs per 100lbs horse weight via oral dose.

Issues with Chondroitin Sulfate

While an important component of joint health, it has not been shown to be effective independent of glucosamine in clinical trials. More studies are showing that glucosamine is proving to be the real active ingredient in these trials.

Chondroitin sulfate is also quite expensive.

Be An Educated Customer

• Check labels for content and concentration

Need to have 10,000mgs glucosamine daily for a 1,000lb horse. A lower dose is not effective.

• Watch out for scoop switch

When 2 scoops are needed for an effective dose, but the cost is calculated on 1 scoop daily.

• Don’t pay for fillers

Flax and soy are common examples, but in general don’t pay for ingredients that don’t have research backed results.

Supreme Top Form

This joint supplement created by Pan Am Vet Corp and based on my own research is one of the most affordable and effective supplements available.

In each dosage unit are two proven ingredients:

• Glucosamine 10,000mgs

• Hyaluronic acid 100mgs

To find out more and try it out for yourself, please visit Pan Am Vet Corp.