Lameness is one of the top three areas of equine veterinary medicine, along with colic and reproduction. Joint disease is the most common cause of lameness and results from pain during movement. The onset of pain can be sudden or long-term, and may result in an obvious lameness or the horse ‘just not being right’. Osteoarthritis, commonly shortened to arthritis, can result from a range of factors, but all result in joint inflammation and degradation. We’ll take a look at how this happens and what we can do about it. Let’s get technical, technical!