Standardbred yearlings that undergo surgical treatment for hock osteochondrosis (OC), a common form of developmental orthopedic disease, can be expected to perform as well as horses that do not suffer from the condition, researchers at the University of Minnesota and Rutgers University have concluded.

In their recent study, the team looked at the 2-year-old race performance records of 278 horses, 133 of which had hock OC lesions that were surgically removed prior their sale as yearlings. The other 145 horses were age-matched controls that were confirmed radiographically to be OC-free.

All the horses were born and raised on the same breeding farm before they went to yearling sales. “Because we know that there are important environmental or management-related risk factors for the development of OC, this gave us a more homogenous group to study,” said Annette McCoy, DVM, MS, PhD, Dipl. ACVS, of the Veterinary Population Medicine Department at the University of Minnesota.

“We also had a smaller group of 94 horses that we were able to follow through their 5-year-old racing season, so four consecutive race seasons," she continued. "Of those horses, 32 were surgically treated for hock OC as yearlings and 62 were unaffected age-matched controls.”

When considering both short and long-term performance, the results showed that horses that had OC lesions removed surgically performed similarly to their unaffected counterparts, said McCoy. “Globally, there were very few differences between the two groups.”

When looking at the OC-affected group specifically, however, the researchers found a couple of differ