Dr. Dean Richardson, chief surgeon for the Kentucky Derby presented by Yum! Brands (gr. I) champion, said in an update following the surgery that the biggest fear is that Barbaro could break his cannon bone.
"We attempted to manage the right hind foot in a cast and then in a custom fabricated brace but it was impossible to have access to the foot for treatment as well as acceptable stability and comfort," Richardson said in a statement released by the University of Pennsylvania's New Bolton Center. " We elected to place his right hind in an external skeletal fixation device in order to provide the foot a chance to heal. This means that two steel pins have been placed transversely through his right hind cannon bone. These pins are connected to external sidebars that in turn are connected to a lightweight alloy foot plate.
"This results in the horse eliminating all weight bearing from the foot; the horse's weight is borne through the pins across his cannon bone. There is significant risk in this approach but we believed it was our only option given the worsening of the right hind foot problem."
The procedure comes three days after Barbaro had two new casts applied to his hind legs. He received a custom-made plastic and steel brace on his right hind leg at that time. He also got a special orthotic brace on the right foot.
Richardson said Barbaro came through the surgery well.
"He had a perfect recovery from anesthesia and has been in and out of the sling since then," he said. "His left hind foot appears to be stable at this time. We remain concerned about both front feet. Remarkably, his attitude and appetite were excellent overnight.
"We will continue to treat Barbaro aggressively as long as he remains bright, alert and eating. This is another significant setback that exemplifies how complex his medical situation remains because both hind limbs have major problems."
Richardson explained that Barbaro had been uncomfortable on his right hind foot because of the development of a "deep subsolar abscess secondary to bruising when he went through a period of discomfort on the left hind foot.
"It is not laminitis but the undermining of the sole and part of the lateral heel region are potentially just as serious," Richardson said.
Co-owner Gretchen Jackson told The Philadelphia Inquirer earlier that Barbaro was again facing tough odds.
"He's got a lot of issues, and not any of them is bad enough to say goodbye. But put together it's not a good day for Barbaro," Jackson said in a story posted on the paper's Web site.
Roy Jackson said he visited Barbaro after the procedure and the colt was alert and ate his grass. Jackson also said there were no additional problems with the left hind and that it was "doing pretty well."
In July, after Barbaro developed laminitis in his left hoof due to uneven weight distribution in the limbs, 80% of that hoof was removed.
"It's nothing that we haven't been through," Roy Jackson said. "Dr. Richardson has said there would be problems along the road."