Equine Osteochondrosis: a challenging enigma

Osteochondrosis (OC) is by for the most important equine developmental orthopaedic disease. Depending on the breed, the incidence may be as high as 25% and losses to the equine industry in economical terms and in terms of welfare are considerable. Osteochondrosis is a multi-factorial disorder in which both hereditary components and management aspects play key roles. Important management factors include nutrition and biomechanical loading of the joints. The concept of the disease has changed considerably over the post years and the condition is now seen as a dynamic process in which lesions may appear and disappear again (be repaired). The last possibility exists as long as the metabolic level of the extracellular matrix of the articular is still high enough to permit such repair. Current research focuses primarily on the molecular mechanisms leading to osteochondrosis and on the genetic background. The complex, multi-factorial character of clinical OC, that can be seen as the outcome of two different processes (pathogenesis and repair), and preliminary results pointing at the involvement of different gene sets for different joints, make it improbable that reliable, simple and decisive genetic tests will soon come onto the market.