Osteoarthritis (OA) is an incurable joint condition that affects horses of all ages and is thought to have a hand in up to 60% of all lameness cases. According to Janny C. de Grauw, DVM, PhD, from the Department of Equine Sciences at Utrecht University in The Netherlands, who recently co-authored a paper on pain in horses with OA, management of the disease requires balanced exercise regimens, medical intervention, and realistic expectations about what the horse can do.
Osteoarthritis results in the progressive degradation and destruction of articular cartilage (the very thin layer of highly specialized connective tissue lining the ends of the long bones where they join). Low-grade inflammation often contributes to the pain, lameness, joint swelling and/or end-stage joint capsule scarring and stiffening. A horse with mild or early OA might experience intermittent bouts of lameness.
"Horses (with mild to moderate OA) can perform at a reasonable level up to quite a high age ... when the owner is aware of the implications of the disease and willing to adjust the workload accordingly," de Grauw said. "Always do a good warm-up, work the horse on a good level surface, and get the right shoes that work for the horse."
She also recommends working with a veterinarian to find a treatment plan to manage the arthritis that works for the individual horse.
When the arthritis flares up and results in lameness, de Grauw said, the horse should be put on stall rest supplemented with hand walking, physical therapy, hosing of the limb, and oral anti-inflammatories as needed. If clinical signs worsen or lameness recurs quickly, the horse's veterinarian might consider adding intra-articular treatment (such as joint injections) to the regimen, she adds.
Stretching might help loosen stiffened joints and maintain joint function, she added. She cautioned, however, that stretching exercises should be performed by a physical therapist or an owner who has been instructed by a professional how to perform them.
De Grauw stresses that masking the pain and continuing to work the horse during a period of lameness will likely facilitate joint deterioration.
Careful management can allow horses with OA to maintain a career under saddle, but once a horse has end-stage OA, he is likely to be permanently lame and should be retired, de Grauw said.
De Grauw cautions not to simply turn a horse with end-stage OA out in a field, however: "A horse in the field generally will not be as closely monitored as one that is ridden regularly. Welfare issues may even be more likely to arise if horses are turned out and pain or lameness no longer noticed and attended to."
She explained that owners managing horses with end-stage OA should focus on pain prevention and treatment using physical therapy, topical or systemic anti-inflammatories, and intra-articular treatment options.
Even with careful management, end-stage OA could become so severe that euthanasia is the most humane treatment option.
"The well-being of an arthritic horse should prevail over economical, practical, and even emotional considerations," she said.
Veterinarians and horse owners can use the suggestions and information put forward by de Grauw and her colleagues to ensure that their arthritic horses enjoy a long and pain-free career in nearly any discipline.
The review "Pain in osteoarthritis" appeared in the December 2010 Veterinary Clinics of North America. The abstract is available online at PubMed.
Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.