Virginia Kraft Payson's homebred Scipion is the latest casualty on the Kentucky Derby (gr. I) trail after X-rays revealed a condylar fracture of his right hind cannon bone.A son of A.P. Indy who has two victories from six starts, Scipion was being aimed toward the April 9 Santa Anita Derby (gr. I) when the fracture was detected following a workout Wednesday."He worked great," Biancone said Friday morning at Keeneland, where he was awaiting the arrival of horses for the upcoming spring meeting. In the work, Scipion was timed in 1:28 2/5 for seven furlongs on grass.Biancone said the colt appeared fine on his return to the barn but the injured area began to swell once he was cooled down. X-rays revealed the injury.Scipion was scheduled to undergo surgery Friday, March 25, by Dr. Paul Thorpe at Dr. Vince Baker's clinic in California.Biancone, who still has Lane's End Stakes (gr. II) morning-live favorite Spanish Chestnut on the Derby trail, said it is unknown how long Scipion will be sidelined.An impressive maiden winner at Saratoga last year, Scipion won the Risen Star Stakes (gr. III) at Fair Grounds in February.