Equine OA: Early Interventions

Tackling osteoarthritis in its early stages can help keep your horse sound, comfortable, and happy in his job

Your 12-year-old sport horse has been coming out of the stall stiff, tracking up a bit short in the warmup, and just doesn’t feel like he’s giving his usual 100%. Before you simply shrug off these anomalies as age- or even weather-related, consider the real cause—they might be early indicators of osteoarthritis (OA). Detecting and managing osteoarthritis in its early stages can go a long way toward keeping your horse sound, comfortable, and happy in his job for years to come.

Suzan Oakley, DVM, Dipl. ACVSMR, ABVP, and Anne Moretta, VMD, MS, CVA, CVSMT, who work in private practice together at Wellington Equine Sports Medicine, in Florida, share their tips for keeping this ever-so-common wear and tear at bay.

What Is Osteoarthritis?

Arthritis is, simply, inflammation of the joint. “Osteoarthritis is a chronic, progressive disease,” says Oakley. “It can initially begin as synovitis, or inflammation of the synovial membrane which lines the joint surface. Eventually, synovitis results in changes to or degradation of the articular cartilage and can progress to include bony changes in the subchondral bone (the layer just below the cartilage surface) in chronic, long-term cases. Subtle pain is an important early clue that may indicate a joint-related problem.”

In sport horses osteoarthritis can develop in a variety of joints, says Moretta. “The majority of cases occur in limb joints that are used for propulsion or are subjected to more concussive weight-bearing,” she says. “The horse’s occupation (dressage, jumping, etc.) plays a role in the location and type of biomechanical loading and repeated stress the joints will have over time.” 

Recognizing Subtle Signs

To pick up on OA early, make sure you’re tuned in to any changes your horse might display in his overall movement and well-being. Prompt identification and intervention are critical to slowing the disease’s progression and keeping the horse agile.

“In private practice we have the opportunity to see and treat horses in the very early stages of the disease,” says Oakley. “Often, changes in movement patterns and (uneven) muscle development are evident before the horse is actually lame. It’s important to be aware of early signs of pain and to evaluate the whole horse.”

Other subtle indicators she says owners should be aware of include:

  • Stiffness that might improve with work;
  • Reduced range of motion of joints;
  • Heat and swelling;
  • Behavioral changes; and
  • Changes in posture.

It is important to give the horse the benefit of the doubt if he’s having behavioral problems, says Moretta. Difficult or “naughty” behavior might be a sign of physical discomfort. Also, “often, limitations in the horse’s athletic ability are labeled as poor performance and may not be recognized as early lameness,” she says. “While not specific to osteoarthritis, these behavioral signs may indicate subtle pain issues.”

Equine Osteoarthritis: Early Interventions

Examining the Whole Horse

When performing a comprehensive evaluation of a horse that’s not quite right, Moretta first collects a complete history, including what issues the client has noticed, and discusses the horse’s occupation and the owner’s goals. From there, her complete assessment involves the axial skeleton (vertebral column), tendons, ligaments, joints, and associated muscles.

“Our approach is very much integrative, so we look at the whole horse,” says Moretta. “First, I’ll notice how the horse is standing and then evaluate movement at the walk from multiple angles and on differing surfaces. We want to analyze the horse’s preferred or ‘compensatory’ movement patterns. These include stride length, straightness, head/neck/back/hip movement, adduction or abduction (movement toward or away from the midline) of the limbs, and overall symmetry. I utilize motion palpation (part of the spinal manipulation exam) to evaluate all the joints in the body, focusing on the limbs and complete spine.”

The whole-horse exam is also good for determining which problems are primary and which are secondary, she says. In addition, checking diagnostic acupuncture points can be very helpful.

Oakley believes owners and veterinarians often overlook muscles, posture, and movement patterns when evaluating these horses. “We want to identify areas of decreased (restricted) or increased (hypermobile) joint motion,” she says. “It is important to treat these affected joints early to reduce inflammation and minimize joint damage. We need an accurate diagnosis to be able to manage pain and to prevent further injury.

“Generally, I’ll start my exam on the opposite ‘corner’ from the lame leg, going over the entire horse,” she continues. “We look at where the clues lead us. Is the horse painful on flexion tests? Is the movement exam abnormal? We let the exam guide our imaging. X rays are the first step, providing information about the bone. A combination of X ray and ultrasound can be extremely helpful in many cases, especially in the stifles and neck.”

For instance, ultrasound provides information about the soft tissue and bone surface interface, Oakley says, and is much more sensitive than X ray for detecting osteophytes (bone spurs).

Also, don’t limit soundness exams solely to when problems are brewing, says Moretta. “When we do periodic performance exams, we look for subclinical (not observable) changes,” she says. “We can use motion palpation to screen for very subtle lameness problems when doing periodic evaluations.”

She says she uses the diagnostic subtle movement or muscle changes to dictate treatment and help prevent long-term and potentially career-ending lameness down the road.

A Multimodal Treatment Approach

Early osteoarthritis treatment and management should include evaluating lifestyle factors that affect your horse’s way of going, our sources say. Veterinarians then have various tools they can recommend to address the condition. Depending on their clients’ goals and budgets, they might suggest:

Shoeing changes A balanced, stable, and supported foot can help reduce joint trauma.

Weight management Preventing horses from becoming overweight also reduces the load-bearing on their joints.

Turnout and light, consistent exercise Keeping horses moving helps reduce inflammation, maintain a healthy weight, decrease stiffness, and encourage slow, steady muscle development for overall strength. “Finding the type of activity that helps maintain tone but does not exacerbate the OA is the key,” says Moretta.

Science-backed nutraceuticals (oral supplements) “Remember, there are no FDA regulations on the equine supplement industry,” says Moretta, who recommends owners purchase from respected companies using ingredients supported by research. Supplements designed to support joint health might contain glucosamine, chondroitin sulfate, and hyaluronic acid, among other ingredients.

Non-steroidal anti-inflammatory drugs (NSAIDs) such as phenylbutazone, firocoxib, and diclofenac sodium topical cream These can be very helpful for long-term management of osteoarthritis, Oakley says, noting that firocoxib produces fewer gastrointestinal side effects than ­phenylbutazone.

Intravenous and intramuscular treatments formulated to minimize joint degeneration “Polysulfated glycosaminoglycan and hyaluronate sodium can be very helpful,” says Oakley, who finds that some horses respond better to one than the other, because the treatments work in different ways and can complement one another. “The hope with these products is that we reduce the need for or frequency of joint injections.”

Intra-articular (in the joint) injections, such as corticosteroids, hyaluronic acid, and regenerative products “Short-term use of corticosteroids is highly effective as an anti-inflammatory treatment, but repeated use in high-motion joints can have some side effects,” says Oakley. “We have also had success with regenerative treatments such as IRAP (interleukin-1 receptor antagonist protein), PRP (platelet-rich plasma), and APS (autologous protein solution). In our clinical experience, regenerative treatments are promising, although they don’t work quite as quickly as corticosteroids. We feel that regenerative treatments may last longer for certain joint problems and may help to decrease the frequency of joint injections that a horse may need during his career.”

Moretta and Oakley stress that in their practice, they don’t inject “by the calendar” (such as every six months) but, rather, based on a complete performance exam and appropriate diagnosis.

Laser, therapeutic ultrasound, and shock wave therapy “These are all effective tools for local control of pain and inflammation in the equine athlete,” says Oakley.

Acupuncture Used as a complementary treatment, acupuncture might help reduce pain and inflammation; relieve muscle spasms; and improve nerve function and range of motion, says Moretta.

Spinal manipulation Moretta says she likes to use acupuncture and spinal manipulation in combination to try to lessen pain and restore normal biomechanics. “If I can reduce inflammation and muscle spasm with acupuncture, I can then use spinal manipulation to increase range of motion and reduce restriction in the joints,” she says. “We need to restore motion to early osteoarthritic joints. By reducing inflammation quickly, you restore more normal nerve function and circulation to the joint so it can heal faster.”

Functional electrical stimulation (FES, using electrotherapy devices to stimulate sensory nerves and muscles) Oakley says this therapy can help restore normal movement to the spine and decrease muscle spasms that may arise because of OA-caused abnormal movement patterns.

Ask your veterinarian which therapies he or she typically performs and which ones might be suitable for your horse.

It Takes a Team

Oakley and Moretta’s approach to managing early OA cases is to explore every avenue. “Our bottom line … is to consider the whole horse,” says Oakley. “Often, when there is primary joint pain, the horse changes his movement pattern, and you may end up with tendon or ligament injuries somewhere else due to a compensatory gait pattern. First you treat the primary cause, then address ancillary issues.”

For instance, in the case of a horse whose movement has changed, Moretta says she and Oakley “figure out why it occurred, treat the pain, and utilize rehabilitation protocols with both Western and integrative approaches.”

Rehabilitation (recovering from injuries) and ‘prehabilitation’ (preventing injuries) are essential parts of keeping horses sound and happy. Regular work with adequate warmup and cool-down—our sources suggest 15 to 20 minutes of walking pre- and post-work—is also key.

“In general, lots of walking is both good ‘prehab’ and ‘rehab’ to stay sound,” says Oakley. “It is important that the horse is not a weekend warrior. Also, older athletes don’t need drilling or repetitive work every day. They need to stay loose. They already know their jobs, so they may benefit from strength work (this varies by horse but can include ground poles, light lateral work, and walking over varied terrain) every other day.”

Our sources agree that keeping horses sound—at any performance level—­involves a “best practices” team effort, including correct shoeing, regular turnout, appropriate weight management, and periodic soundness exams to screen for brewing subclinical issues.

“It’s the team approach that is so important: the client/rider, the farrier, the vet, traditional and complementary medicine,” says Moretta.