Effects of Racing Surface and Turn Radius on Fatal Limb Fractures in Thoroughbred Racehorses

North American Thoroughbred racing is conducted on three types of surfaces—dirt, turf, and synthetic. The tracks are oval, races run counterclockwise. loading right left limbs expected to differ as a function turn radius, banking, surface, gait asymmetry. Hind forelimbs also have different functions related propulsion turning, respectively. This study uses the Equine Injury Database for race starts from 1 January 2009 through 31 December 2014, compare injury rates across participating racetracks. data limited catastrophic injuries in which horses died or were euthanized due fracture within 72 h start race. Overall lower turf synthetic surfaces pattern limb vs. fore hind different. Regardless more likely fracture. Dirt showed higher forelimb compared other surfaces, experience fatal than dirt. but only dirt surfaces.