Epidemiology of race-day distal limb fracture in flat racing Thoroughbreds in Great Britain (2000-2013).

The research investigates risk factors for distal limb fractures in Thoroughbred racehorses in flat racecourses in Great Britain. It reports that factors like firmness of the track, increased race distance, and the horse’s first year of racing increased the risk of fractures, while the number of previous races the horse engaged in were protective.

Methodology

• The study used retrospective cohort methods, analyzing data from all flat racing starts in Great Britain from 2000 to 2013.
• Various sets of information were gathered which included horse, race, course, trainer, and jockey data for each start, and injury data from the race day as reported by on-site veterinarians.
• Mixed-effects logistic regression analyses were then used to find associations between these exposure variables and instances of distal limb fracture. The analyses were performed on data from all starts as well as only turf starts.

Results

• 806,764 starts and 624 instances of distal limb fractures were included in the study, with 548,571 of these starts and 379 fracture cases happening on turf surfaces.
• Three prominent factors that increased the likelihood of fracturing were identified: increased firmness of race tracks, increased racing distance, and the horses racing in their first year.
• The study also found that the more a horse had raced previously, the less likely they were to suffer a distal limb fracture, suggesting that previous race starts had a protective effect.
• Trainer performance also played a significant role in the likelihood of a horse sustaining a distal limb fracture. The study further revealed that with increasing age, the risk of fracture increased.
• Additionally, starting in selling or claiming races or Group 1, Group 3 or claiming races posed higher odds of a distal limb fracture.

Conclusion

• All types of distal limb fractures were considered as one outcome for the purposes of this research.
• Confirmed risk factors for this type of injury included the firmness of the track (going), length of the race, and number of races a horse had previously run.
• New risk factors were also identified in this study, related to horse and trainer performance and the type of race.
• The researchers believe that by highlighting these risk factors, preventive measures can be put in place to reduce the occurrence of distal limb fractures in flat racing horses.