Osteoarthritis poses a threat to soundness and athletic longevity in any horse but especially senior horses. The condition can affect horses in obvious ways, such as lameness, but sometimes the signs of arthritis are subtle. Because horses are prey animals, they are adept at hiding pain, which can make it challenging to identify these more subtle signs of discomfort.

“Subtle signs of osteoarthritis in senior horses can include alterations in their everyday activities,” says Kara Brown, VMD, Dipl. ACVSMR, assistant professor of equine sports medicine and rehabilitation at the University of Pennsylvania’s New Bolton Center, in Kennett Square.  “For instance, a horse may be slower to come in from the field, have difficulty getting down to roll, or standing up from lying down. In rare cases, horses can even begin showing signs of sleep deprivation because they aren’t able to lie down and rest, resulting in periods of collapse due to exhaustion.” Under saddle, these horses might present with poor performance, such as being unable to complete a flying lead change, or lack of impulsion.

Noticing these early subtle signs of arthritis before they progress is crucial, says Kyla Ortved, DVM, PhD, Dipl. ACVS, Dipl. ACVSMR, associate professor of large animal surgery at New Bolton Center. “Our goal with osteoarthritis is early recognition of joint injuries and inflammation. That way, we can limit the progression of arthritis and keep the joint as healthy as possible as the horse ages.”

Working The Arthritic Horse

“Similar to humans, becoming sedentary is the kiss of the death for a horse with arthritis,” says Ortved. “Horses do better when they are allowed to, and encouraged to, move around and engage in controlled exercise.”

With regular maintenance, many horses continue working and competing into their senior years. “Regular exercise, a healthy diet that is not too high in protein (although each horse’s needs vary depending on their metabolic status) and making sure that the horse’s body condition remains as ideal as possible can make a huge difference in these senior horses,” says Jose Garcia-Lopez, VMD, Dipl. ACVS, Dipl. ACVSMR, associate professor of large animal surgery at New Bolton. “If a senior horse develops pain or unsoundness due to osteoarthritis, they will tend to move around less and begin using their bodies in an incorrect fashion which results in loss of muscle tone and conditioning.” 

Implementing regular carrot stretches for 10-15 minutes prior to exercise can help a senior horse’s body warm up to help combat loss of muscle and reduce stiffness. Some horses might benefit from 10 minutes of longe work (at the walk and trot) prior to working under saddle to allow them time to warm up without a rider. Walking and trotting over ground poles and cavaletti can also help senior horses maintain their muscle tone, said Garcia-Lopez. After exercise, topical therapies, such as liniment or ice boots can be used to reduce inflammation, pain, and stiffness.

Supplements, Medications, and Other Ways to Manage Arthritis in Horses

If your horse has been diagnosed with osteoarthritis, feed-through supplements might be used to slow its progression or reduce pain levels.

“There are numerous studies being performed and published evaluating the effects of other supplements, such as omega-3 fatty acids, glucosamine, chondroitin sulfate, and others,” says Brown. “Unfortunately, some label claims for supplements are not supported by good-quality clinical trials, and I would encourage anyone considering oral supplements to evaluate the evidence behind their use and consult your veterinarian about any potential risks with use in your horse.”

Instead, veterinarians agree that managing body weight has a more significant effect on senior horses with arthritis, especially in those that are overweight. “Increased weight and fatty tissue can not only increase the amount of load on the limbs but also result in more pain and lameness in horses with osteoarthritis,” says Brown. Osteoarthritis can make weight management challenging for horse owners because it can lead to reduced movement, lack of calorie output, and, therefore, more weight gain. Be sure to monitor your senior horse’s weight and body condition score regularly to prevent him from losing muscle condition and gaining weight.

Veterinarians might prescribe oral medications for pain management in senior horses with osteoarthritis, including phenylbutazone, firocoxib, acetaminophen, and pregabalin. Most practitioners recommend monitoring your horse periodically using blood work to ensure he’s maintaining normal organ function on these medications.

Our sources agree that intra-articular therapies can help decrease inflammation within the joint. Veterinarians base their injectable joint therapy selections primarily on your horse’s specific needs, such as which joint is affected, the severity of the arthritis, and potential side effects of the medication. 

While there is currently no injectable medication that completely regenerates damaged cartilage, treating joints with osteoarthritis early in the disease process—based on clinical signs—can decrease inflammation, slow the disease’s progression, and reduce clinical signs. “I prefer to use joint injections on an as-needed basis rather than just keeping horses on a specific maintenance schedule,” says Ortved.

In addition to the interventions described, work closely with your farrier and veterinarian team to ensure the biomechanics of the hoof are optimized to improve your horse’s comfort. “Many horses can be managed very well barefoot with timely trimming; however, some horses do seem more comfortable with the additional support of shoes,” Ortved adds.

Take-Home Message

If your senior horse has been diagnosed with osteoarthritis, watch for subtle signs of pain, continually monitor your horse’s comfort levels, and maintain a good working relationship with your veterinarian so you can be ready to make changes to your horse’s treatments and management strategies when needed. Warming your horse up well before exercise and maintaining them at a healthy weight can also help reduce the stress placed on their joints.