Joint health is important in our horses, considering most are kept for athletic purposes and because we want them to remain comfortable in older age. Unfortunately, horses – like us – can suffer from osteoarthritis and age-related stiffness and lack of mobility. There is no cure for osteoarthritis, and treatments aim to relieve pain and stiffness and improve mobility. Treatments include drugs, feed supplements, weight reduction (if necessary), muscle-strengthening work and maintenance of movement.
The problem with using drugs to treat osteoarthritis is that most of the drugs we currently have available – despite giving good short-term pain relief – will, used long term, accelerate the cartilage damage that typifies osteoarthritis. Non-steroidal anti-inflammatories commonly used in horses decrease proteoglycan synthesis when used for longer than a couple of weeks. Steroid injections into joints will dampen inflammation effectively, but may also have detrimental long-term effects on cartilage as well as carry risks such as laminitis. Vet Peter Clegg, from the University of Liverpool Teaching Hospital in the UK, outlined the risks of using corticosteroid joint injections, especially in horses without a clear joint pathology diagnosis. He believes they should be used as a last resort and only in carefully-selected cases.
Many owners use feed supplements containing a variety of nutraceutical ingredients including glucosamine, chondroitin and MSM, as well as herbs such as devil’s claw and boswellia (amongst many others) in order to treat problems and maintain joint health. There has not been enough good quality research carried out in horses into these compounds, so we cannot exclude their usefulness. Horse and Hound vet writer Peter Green recently noted that ‘exercise keeps old horses more supple than joint supplements’ based on one study with negative results. There is no doubt that exercise is key in maintaining joint health and probably the most important ‘treatment’ for affected horses. However, the quoted study used a product made from a combination of ingredients and could well have contained ineffective levels.
Authors of a Cochrane (an independent body who review health research) review of glucosamine for osteoarthritis in humans highlighted the problem with the variable amount of glucosamine used in commercial preparations and how that could contribute to the lack of effect in some trials. Some horse products contain around 1500 mg (1.5 g) of glucosamine, which is the recommended human dose. A more realistic horse dose would be 10,000 mg (10 g) daily.
If your horse has trouble with their joints, first keep them moving as much as possible, keep their muscles healthy and conditioned to support their joints, ensure they are slim and then reach for a joint supplement but make sure it supplies adequate levels of active ingredients.