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Equine veterinary journal2025; doi: 10.1111/evj.14493

Risk factors for superficial digital flexor tendinopathy in Thoroughbred racehorses in South Korea (2015-2019).

Abstract: Superficial digital flexor (SDF) tendinopathy is one of the most common musculoskeletal diseases in Thoroughbreds and a major cause of retirement from racing among racehorses in South Korea. However, there are no previous epidemiological studies on SDF tendinopathy-related risk factors for racehorses in South Korea. The interventions derived from such a study could reduce the occurrence of SDF tendinopathy and, therefore, extend horses' racing careers. Objective: To identify the risk factors associated with SDF tendinopathy for Thoroughbreds in South Korea. Methods: Retrospective case-control study (2015-2019). Methods: A total of 101 Thoroughbreds that were diagnosed with SDF tendinopathy following a recorded fast-exercise (training gallop, trial racing, racing) between 2015 and 2019 were included in the study. Additionally, 304 healthy Thoroughbreds (319 events) with at least one recorded fast-exercise between 2015 and 2019 were also included as controls. Multivariable logistic regression was used to identify risk factors for SDF tendinopathy. Results: SDF tendinopathy was significantly more likely to be diagnosed after racing or trial racing than after galloping. Horses with lower grades (6, ungraded) based on racing performance were associated with a higher risk of SDFT injuries. An increased risk of SDFT injury was observed with fewer gallop training days in the previous 60 days to the last fast-exercise, more canter training days in the previous 180 days, or having a period of no fast-exercise for over 90 days in the year prior to the event. Conclusions: Information on the distance and speed of gallop training was not available. Conclusions: The implementation of risk profiling and other preventive measures for horses with fewer gallop training days before racing could help minimise the number of horses sustaining SDF tendinopathy.
© 2025 The Author(s). Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
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Publication Date: 2025-03-19 PubMed ID: 40104935DOI: 10.1111/evj.14493Google Scholar: Lookup
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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.

This research study investigates the risk factors associated with superficial digital flexor (SDF) tendinopathy in Thoroughbred racehorses, a common health issue that often leads to retirement from racing. Over four years, the researchers studied both horses diagnosed with this condition and healthy control horses to identify significant risk factors.

Research Methodology

The study followed a retrospective case-control method over a period of five years from 2015 to 2019.

  • A total of 101 Thoroughbreds were studied that had been diagnosed with SDF tendinopathy. These horses had been documented as they exercised strenuously through training gallops, trial racing, and actual racing.
  • Additionally, 304 healthy Thoroughbreds were included as controls. These horses also had documented records of at least one form of strenuous exercise between 2015 and 2019.
  • The researchers used multivariable logistic regression to identify risk factors for SDF tendinopathy.

Key Findings

In evaluating the data collected, the researchers found several key factors that were significantly associated with SDF tendinopathy.

  • The data showed that SDF tendinopathy was more likely to be diagnosed following racing or trial racing compared to after training gallops.
  • Horses with lower performance grades (6, ungraded) had a higher risk of SDF tendinopathy.
  • An increased risk was noticed in horses having fewer gallop training days in the 60 days before their last strenuous exercise.
  • Similarly, horses having more canter training days in the 180 days before their last strenuous exercise also had an increased risk.
  • Horses that had not undergone any fast-exercise for over 90 days in the year prior to the event were at increased risk.

Limitations and Conclusion

One major limitation of the study was the unavailability of detailed information on the distance and speed of the gallop training sessions. This could have provided a more comprehensive understanding of the intensity of training sessions and their relation to the development of SDF tendinopathy.

Despite this, the study draws a meaningful conclusion — implementing risk profiling and preventive measures, particularly for horses with fewer gallop training days before racing, could help reduce the number of horses developing SDF tendinopathy. The knowledge of these risk factors may contribute to maintaining the health of racing Thoroughbreds, increasing their active racing careers, and improving the overall wellbeing of these horses

Cite This Article

APA
Choi Y, Parkin T. (2025). Risk factors for superficial digital flexor tendinopathy in Thoroughbred racehorses in South Korea (2015-2019). Equine Vet J. https://doi.org/10.1111/evj.14493

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English

Researcher Affiliations

Choi, Yungi
  • Veterinary Department, Korea Racing Authority, Gwacheon-si, South Korea.
Parkin, Tim
  • Bristol Veterinary School, University of Bristol, Langford, UK.

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Citations

This article has been cited 1 times.
  1. Yuan X, Yao X, Zeng Y, Wang J, Ren W, Wang T, Li X, Yang L, Yang X, Meng J. The Effect of Training on the Expression of Protein and Metabolites in the Plasma Exosomes of the Yili Horse. Animals (Basel) 2026 Jan 6;16(2).
    doi: 10.3390/ani16020158pubmed: 41594348google scholar: lookup
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