Bone spavin is most commonly seen in adult performance and pleasure horses, and sometimes young racehorses. It is one of the most common cause of hindlimb lameness in horses. Bone spavin is actually a more specific term used to describe horses with osteoarthritis of the lower joints within the hock (usually the distal intertarsal and tarsometatarsal joints).

Bone spavin is suspected to occur as a result of repeated compression and rotation of the small bones within the hock. Horses with sickle or cow hocks are more at risk of developing bone spavin.

Clinical Signs of Bone Spavin in Horses

Horses with bone spavin may or may not develop a swelling on the inside lower hock area. Most horses will usually develop various degrees of lameness in one or both of their hind legs, causing them to move with a shortened stride and choppy gait. The toes of their feet may also appear square-shaped, as a result of dragging of the toe on the affected side. There may also be some muscle wasting over the quarters on one or both sides of their body. When both of the horse's hocks are affected, it often causes a loss in the performance.