Thursday September 12th, 09.20 – 09.45 Clinical aspects of subchondral bone pain in the fetlock in racehorses and sports horses

Subchondral bone pain is often the result of a stress-adaptation mismatch injury involving the condyles of the third metacarpal/metatarsal bones, frequently involving both forelimbs or both hindlimbs, or all four limbs. Therefore the presenting complaint is usually loss of action or decline in performance, rather than overt lameness. The horse may have a short scratchy trot and prefer to canter than to trot. However, if the hindlimbs are involved the canter may lack hindlimb impulsion, the horse tending to bunny hop behind. However, less commonly the horse may present with an overt unilateral lameness, but following diagnostic analgesia contralateral limb lameness may become apparent. Increased mineralisation of the trabecular bone may predispose to fracture resulting in acute-onset, severe lameness, but frequently poor action preceded this.