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Home / Equine Research Bank / Equine Vet J / Post-mortem computed tomography features associated with fra...
Equine veterinary journal2025; doi: 10.1111/evj.14465

Post-mortem computed tomography features associated with fracture of the fetlock joint in racing Thoroughbreds.

Abstract: Post-mortem studies have shown that fractures involving the metacarpophalangeal/metatarsophalangeal or fetlock joint are associated with focal areas of microdamage. Identification of computed tomography (CT) features consistent with microdamage and their association with fracture may aid in identification of horses at risk of fracture. Objective: To identify CT features associated with fracture of the metacarpophalangeal/metatarsophalangeal joint. Methods: Retrospective cohort study. Methods: Post-mortem CT images of 367 limbs from 157 Thoroughbred racehorses were graded for CT features. Multivariable logistic regression models were generated. Intraclass correlation coefficients of key CT features to assess intra and inter-rater reliability were calculated. Results: The presence of lysis within the subchondral/trabecular bone underlying the lateral and, or, medial parasagittal groove (PSG) of the distal third metacarpus/tarsus (odds ratio [OR] 9.6; 95% confidence interval [CI] 4.3-21.3; p < 0.001) and sclerosis of the palmar subchondral and trabecular bone underlying the lateral and medial PSG that projected proximoaxially (OR 4.6; 95% CI 1.1-19.02; p = 0.03) were associated with condylar fracture. The presence of a proximal sesamoid bone (PSB) lytic lesion (OR 5.3; 95% CI 1.2-23.6; p = 0.03) and increasing medial PSB density (OR 1.02; 95% CI 1.00-1.03; p < 0.001) were associated with PSB fracture. Palmar osteochondral disease grade was not associated with condylar (p = 0.8) or PSB fracture (p = 0.09). Inter rater reliability was moderate for the presence of PSG lysis (ICC 0.7; 95% CI 0.6-0.8) and shape of sclerosis in the lateral condyle (ICC 0.6; 95% CI 0.5-0.8). Conclusions: The extent of lysis within the PSG and the volume of the PSB could not be as accurately obtained in limbs with multiple fracture fragments. Conclusions: CT examination of fetlock joints post-mortem identified changes associated with both metacarpal condylar fracture and PSB fracture in racehorses. These findings show that pre-race CT screening has the potential to reduce fracture rates.
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Publication Date: 2025-02-10 PubMed ID: 39925247DOI: 10.1111/evj.14465Google 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.

The research article investigates the computed tomography (CT) features that are linked with fractures in the fetlock joint of Thoroughbred racehorses. The study concludes that pre-race CT screening could potentially help to decrease the instances of these fractures.

Study Objective and Methods

  • The primary motivated of the research was to discover the CT features which are related to the fracture of the metacarpophalangeal/metatarsophalangeal joint in racehorses.
  • Using a retrospective cohort study method, post-mortem CT images of 367 limbs from 157 Thoroughbred racehorses were evaluated for these features.
  • From the data collected, multivariable logistic regression models were produced and intraclass correlation coefficients of key CT features were computed to gauge intra and inter-rater reliability.

Results

  • The study found that lysis (decomposition) within the subchondral/trabecular bone underlying the lateral and, or, medial parasagittal groove of the distal third metacarpus/tarsus had a significant association with condylar fracture.
  • Furthermore, sclerosis of the palmar subchondral and trabecular bone underlying the side parts of parasagittal groove that projected proximoaxially also showed an association with condylar fracture.
  • The presence of a proximal sesamoid bone lytic lesion and increased medial proximal sesamoid bone density were found to be associated with proximal sesamoid bone fracture.
  • However, the grade of the palmar osteochondral disease was discovered to not have any significant association with either condylar or proximal sesamoid bone fracture.

Conclusions

  • The researchers concluded that the extent of lysis within the parasagittal groove and the volume of the proximal sesamoid bone could not be accurately obtained in limbs featuring multiple fracture fragments.
  • The CT examination of fetlock joints post-mortem identified changes associated with both metacarpal condylar fracture and proximal sesamoid bone fracture in racehorses.
  • The findings propose the potential benefits of pre-race CT screenings for Thoroughbred racehorses as a method to identify those at risk and possibly reduce fracture rates.

Cite This Article

APA
Beck C, Hitchens PL, Whitton RC. (2025). Post-mortem computed tomography features associated with fracture of the fetlock joint in racing Thoroughbreds. Equine Vet J. https://doi.org/10.1111/evj.14465

Publication

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

Researcher Affiliations

Beck, Catherine
  • Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.
Hitchens, Peta L
  • Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.
Whitton, R Christopher
  • Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Grant Funding

  • University of Melbourne
  • Racing Victoria Limited
  • Victorian Racing Industry Fund of the Victorian State Government

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Citations

This article has been cited 1 times.
  1. Beck C, Morrice-West AV, Muir P, Hitchens PL, Whitton RC. Quantification of the difference in hounsfield units of an electron density phantom between a conventional and standing computed tomography machine. Vet Res Commun 2025 Jun 17;49(4):228.
    doi: 10.1007/s11259-025-10789-7pubmed: 40526177google scholar: lookup
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