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The role of catastrophic injury or sudden death of the horse in race-day jockey falls and injuries in California, 2007-2012.

REASONS FOR PERFORMING STUDY
If equine conditions with high likelihood of jockey injury can be determined and subsequently prevented, jockey safety can be enhanced.


OBJECTIVES
To identify racehorse injuries or conditions with greatest risk for jockey falls and injuries.


STUDY DESIGN
Retrospective correlation of race-day jockey fall and injury data with racehorse fatality data.


METHODS
Thoroughbred (TB) and Quarter Horse (QH) racehorse cause of death and jockey fall and injury data for California flat races were reviewed for a 6-year period. Race and jockey race ride population data were used to determine jockey fall and injury incidence rates relative to cause of racehorse death, and were assessed using Poisson regression. Differences in proportions were assessed using Fisher's exact, Pearson's χ(2), and Cochran-Mantel-Haenszel tests.


RESULTS
707 racehorses experienced race-related catastrophic injury or sudden death. 199 jockeys had 601 falls with 325 injuries. Jockeys were 162 times more likely to fall (95% confidence interval 137-192; P<0.001) and 171 times more likely to be injured (95% confidence interval 140-208; P<0.001) when they rode a horse that died in a race. We infer that jockeys were more likely to fall or be injured when riding in QH races than in TB races because of a higher incidence of horse fatalities in QH races. Jockey falls occurred with 24% of TB and 36% of QH race-related horse fatalities, and jockey injury occurred in 64% of falls. Jockey falls were most common with TB fetlock injuries and QH carpal, metacarpal and fetlock injuries; and with axial, bilateral and multiple injuries compared with appendicular, unilateral and singular injuries, respectively.


CONCLUSIONS
Prevention of the most common catastrophic injuries and conditions of the racehorse, e.g. fetlock injuries, may be most effective at decreasing rates of falls and injuries to horseracing jockeys during racing.