Osteoarthritis of one of the joints within the hock (the talocalcaneal joint) is a rare cause of acute onset of severe lameness, but clinical findings and diagnostic analgesia (such as blocking a joint) often fail to identify precisely the site of pain. Roger Smith, MA, VetMB, PhD, DEO, Dipl. ECVS, MRCVS, professor of equine orthopedics in the Department of Veterinary Clinical Science at the Royal Veterinary College published research in the March 2005 Equine Veterinary Journal supporting arthrodesis, or fusion of this joint with two or more screws to treat talocalcaneal osteoarthritis.

Case reports of horses with hind limb lameness and radiographic evidence of this form of arthritis were studied. Ten horses were treated conservatively with intraarticular injection of corticosteroids. Due to persistant lameness, six of these horses were later euthanatized, three were retired, and one was used for light work while being administered non-steroidal anti-inflammatory drugs.

Another six horses underwent arthrodesis to attempt to relieve lameness.

“Horses managed by surgical treatment of the talocalcaneal joint had consistent improvement in lameness, with four being able to perform light work despite the lameness,” said Smith. The two other horses were retired despite some improvement in their condition