While equine surgeons enjoy sharing the mantra “if in doubt, cut it out,” researchers recently reported that when it comes to some osteochondritis dissecans (OCD) lesions, letting nature run its course might be the better option.

Such lesions occur because of a loss of blood supply to the developing bone/cartilage junction in the joint.

“This leads to, effectively, a fracture of the cartilage, which forms a loose flap over the bone cartilage,” says Tom Russell, BVMS, Dipl. ECVS, from the Bendigo Equine Hospital, in Victoria, Australia. “In some cases the flap can fall off and become loose in the joint, causing swelling in the joint and lameness. Such cases are generally surgical candidates.”

In recent years, however, owing to the increased practice of taking X rays prior to Thoroughbred yearling sales, veterinarians commonly diagnose OCD in weanlings in the absence of clinical signs. This means that owners of weanling and yearling Thoroughbreds with OCD have the option of pursuing surgery before signs of disease occur, which is referred to as “preemptive” surgery