Date of Award


Degree Type


Degree Name

Master of Science (MS)


Basic Medical Sciences

First Advisor

Russell P. Main

Committee Chair

Russell P. Main

Committee Member 1

Timothy B. Lescun

Committee Member 2

Joseph M. Wallace


Catastrophic skeletal fractures in racehorses are devastating not only to the animals, owners and trainers, but also to the perception of the sport in the public eye. The majority of these fatal accidents are unlikely to be due to chance, but are rather an end result failure from stress fractures. Stress fractures are overuse injuries resulting from an accumulation of bone tissue damage over time. Because stress fractures are pathological, it is possible that overt fractures can be predicted and prevented. In this study, third metacarpals (MC3) from 33 thoroughbred racehorse comprised of 8 non-fractured controls and 25 horses that experienced fracture of some limb bone were evaluated for correlative factors for fracture using reference point indentation (RPI; Biodent, Osteoprobe), peripheral quantitative computed tomography (pQCT) and Raman spectroscopy. As measured by RPI, fractured racehorses had reduced indentation distance of the RPI probe on the dorsal surface of the MC3, compared to controls. pQCT analysis revealed that horses that fractured long bones had lower cortical bone mineral density in the distal metaphysis than sesamoid fractured or control horses. Also in the distal metaphysis, horses that fractured their MC3s had greater trabecular and total bone mineral content, as well as greater geometric properties compared to other fracture and control groups. Raman spectroscopy showed that the lateral aspect of horses with MC3 fractures had greater mineral:matrix, carbonate:phosphate and decreased bone remodeling ratios compared to the other fractured and control groups. Several parameters between the two RPI devices were also significantly negatively correlated. This study shows that there are likely correlative factors for fracture using these three types of tools, and that future studies could lead to the development of a predictive model for fracture.