[The horse as an athlete: an animal model of choice for sports medicine: sonographic studies of joint disorders].

Equine diagnostic sonography was initially used for the diagnosis and documentation of tendon injuries. Since 1990, this technique, along with radiography, has become an indispensable imaging procedure for the diagnosis of equine joint injuries. Sonography provides precise diagnostic information on the synovial membrane and fluid, the articular cartilage, subchondral bone and joint margins, the ligaments and menisci, and the anatomical structures involved in periarticular swelling or enlargement. Improvements in ultrasound machines and better superficial and deep image resolution allow us to examine every joint of the frontlimbs and hindlimbs, including the most proximal, as well as most of the joints of the equine vertebral column, pelvis and head. As a professional athlete, the horse is an excellent animal model of sport-related joint disorders in humans. The large size of its anatomical structures facilitates high-quality imaging. Sensitive and specific diagnostic sonography of joint injuries requires strict standardization of the technical approach to each joint structure and also a precise knowledge of equine joint anatomy.