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Home / Equine Research Bank / Animals (Basel) / The Risk Factors for Musculoskeletal Injuries in Thoroughbre...
Animals : an open access journal from MDPI2021; 11(2); doi: 10.3390/ani11020270

The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury.

Abstract: Musculoskeletal injuries (MSI) continue to affect Thoroughbred racehorses internationally. There is a strong interest in developing training and management strategies to reduce their impact, however, studies of risk factors report inconsistent findings. Furthermore, many injuries and fatalities occur during training rather than during racing, yet most studies report racing data only. By combining racing and training data a larger exposure to risk factors and a larger number of musculoskeletal injuries are captured and the true effect of risk factors may be more accurately represented. Furthermore, modifications to reduce the impact of MSI are more readily implemented at the training level. Our study aimed to: (1) determine the risk factors for musculoskeletal injuries and whether these are different for two-year-old and older horses and (2) determine whether risk factors vary with type of injury. This was performed by repeating analyses by age category and injury type. Data from 202 cases and 202 matched controls were collected through weekly interviews with trainers and analysed using conditional logistic regression. Increasing dam parity significantly reduced the odds of injury in horses of all age groups because of the effect in two-year-old horses (odds ratio (OR) 0.08; 95% confidence interval (CI) 0.02, 0.36; p < 0.001). Increasing total preparation length is associated with higher odds of injury in horses of all ages (OR 5.56; 95% CI 1.59, 19.46; p = 0.01), but particularly in two-year-old horses (OR 8.05; 95% CI 1.92, 33.76; p = 0.004). Increasing number of days exercised at a slow pace decreased the odds of injury in horses of all ages (OR 0.09; 95% CI 0.03, 0.28; p < 0.001). The distance travelled at three-quarter pace and above (faster than 13 m/s; 15 s/furlong; 800 m/min; 48 km/h) and the total distance travelled at a gallop (faster than 15 m/s; 13 s/furlong; 900 m/min; 55 km/h) in the past four weeks significantly affected the odds of injury. There was a non-linear association between high-speed exercise and injury whereby the odds of injury initially increased and subsequently decreased as accumulated high-speed exercise distance increased. None of the racing career and performance indices affected the odds of injury. We identified horses in this population that have particularly high odds of injury. Two-year-old horses from primiparous mares are at increased odds of injury, particularly dorsal metacarpal disease. Two-year-old horses that have had a total preparation length of between 10 and 14 weeks also have increased odds of injury. Horses of all ages that travelled a total distance of 2.4-3.8 km (12-19 furlongs) at a gallop in the last four weeks and horses three years and older that travelled 3.0-4.8 km (15-24 furlongs) at three-quarter pace and above also have increased odds of injury. We recommend that these horses should be monitored closely for impending signs of injury. Increasing the number of days worked at a slow pace may be more effective for preventing injury, if horses are perceived at a higher risk, than resting the horse altogether. Early identification of horses at increased risk and appropriate intervention could substantially reduce the impact of musculoskeletal injuries in Thoroughbred racehorses.
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Publication Date: 2021-01-21 PubMed ID: 33494508PubMed Central: PMC7910838DOI: 10.3390/ani11020270Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research aimed to identify the potential risk factors for musculoskeletal injuries in Thoroughbred racehorses, studying whether these factors vary with the horse’s age and type of injury.

Research Purpose

  • The researchers aimed to explore the different risk factors contributing to musculoskeletal injuries in racehorses and verify if these factors vary for horses of different ages, especially comparing two-year-old horses to older ones.
  • The study also examined whether these risk factors shift depending on the type of the injury.

Research Methodology

  • The researchers analysed data from 202 cases, and 202 corresponding controls. These were collected via weekly interviews with the horse trainers.
  • The data collected was analyzed using conditional logistic regression method.

Key Findings

  • Increasing the number of births a mare, or female horse, had significantly reduced the risk of injury in her offspring, especially for two-year-old horses.
  • Protracted preparation length was associated with heightened injury risk in all age groups of horses, but particularly in two-year-old animals.
  • The study found that horses of all ages that executed more days of slow-paced exercise had decreased risk of injury.
  • The distance the horses covered at three-quarter pace and galloping (above certain speeds) during the past four weeks significantly influenced their odds of getting injured.
  • The association between high-speed exercises and risk of injury was non-linear. Starting, the chances of injury rose with increasing distances covered at high speed; however, it subsequently decreased as the distance increased further.
  • Racing history and performance indices did not have any significant effect on the injury risk.

Enhanced Risk Sections

  • The research identified certain groups of horses with increased injury odds. Specifically, two-year-old horses from mares giving birth for the first time had a higher risk of injury, particularly dorsal metacarpal disease
  • Two-year-old horses that had gone through a total preparation period of between 10 and 14 weeks also generally had higher odds of injury.
  • Horses of all ages that had run a total distance of 2.4-3.8 km at a gallop in the last four weeks, and horses three years and older covering 3.0-4.8 km at three-quarter pace, were also found to have higher odds of injury.

Recommendations and Conclusions

  • The researchers recommended that these high-risk horses should be regularly monitored for any forthcoming injury signs.
  • They suggested that increasing the number of days of slow-paced work might be more effective in preventing injury, especially if the horses were identified as higher risk, than allowing the horse to rest entirely.
  • With early identification of horses at an elevated risk and implementing appropriate interventions, the impact of musculoskeletal injuries in Thoroughbred racehorses could be considerably reduced.

Cite This Article

APA
Crawford KL, Finnane A, Phillips CJC, Greer RM, Woldeyohannes SM, Perkins NR, Kidd LJ, Ahern BJ. (2021). The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury. Animals (Basel), 11(2). https://doi.org/10.3390/ani11020270

Publication

Animals : an open access journal from MDPI
ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 11
Issue: 2

Researcher Affiliations

Crawford, Kylie L
  • School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia.
  • School of Public Health, The University of Queensland, Herston, QLD 4006, Australia.
Finnane, Anna
  • School of Public Health, The University of Queensland, Herston, QLD 4006, Australia.
Phillips, Clive J C
  • Curtin University Sustainability Policy (CUSP) Institute, Curtin University, Perth, WA 6845, Australia.
Greer, Ristan M
  • Torus Research, Bridgeman Downs, QLD 4035, Australia.
  • School of Medicine, The University of Queensland, Herston, QLD 4006, Australia.
Woldeyohannes, Solomon M
  • School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia.
Perkins, Nigel R
  • School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia.
Kidd, Lisa J
  • School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia.
Ahern, Benjamin J
  • School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia.

Conflict of Interest Statement

The authors declare no conflict of interest.

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