Epidemiology of lameness and athletic performance in Thoroughbred pinhooked horses

This research had two main objectives. The first was to investigate associations between lameness and athletic performance in Thoroughbred pinhooked horses. Study results identified a high incidence of lameness during training, most injuries were diagnosed in joints, lameness was more frequent in hind than forelimbs, and speed was associated with sale price. Most study horses with a high purchase price had a reduced number of furlongs galloped and were classified as fast at the sales. Lameness alone was not associated with sale prices but lameness was associated with reduced exercise, which was more evident among lame horses with a high purchase price compared to lame horses with a low purchase price. These results support the conclusion that yearling pinhooked horses suffer a high incidence of lameness and that financial return was significantly different among horses classified as fast, average or slow at the sales and that yearling purchase price affects the trainers' management decision on the amount of training allocation prescribed to lame horses.;The second overall objective was to determine the prevalence of abnormal radiographic findings and their association with future racing performance. Study results determined prevalence of radiographic abnormalities in the fore and hind limbs, established the prevalence of presale arthroscopic surgery, and reported sale prices were higher in horses with a history of presale surgery than in horses without. Statistical modeling was conducted to adjust for gender, history of arthroscopic surgery, and purchase price. The odds of starting a race were lower in horses with forelimb proximal sesamoid osteophytes/enthesophytes and in horses with hind limb P1 OC fragments compared to horses that did not have these changes. Selected radiographic findings were not associated with outcome variables for starts placed, money earned, or money earned per start.