Letter to the Editor: Can quantitative computed tomography detect bone morphological changes associated with catastrophic proximal sesamoid bone fracture in Thoroughbred racehorses?

The research focuses on the potential use of computed tomography (CT) to detect changes in bone morphology that could be associated with catastrophic proximal sesamoid bone fractures in Thoroughbred racehorses. By analyzing horses that underwent necropsies after euthanasia or death on racetracks, the study identifies potential indicators for the fracture risk of equine athletes.

Overview of Research

• The research was based on a specific group of Thoroughbred racehorses which had gone through necropsy post death or euthanasia on racetracks. The study looked at eight horses that suffered from proximal sesamoid bone fracture. They were compared with eight other horses with unrelated diseases or injuries for control. Age and sex were matched between the two sets of horses.
• The study explored whether horses with these bone fractures had a significantly higher bone density than horses without these fractures.
• The secondary objective of the study was also to assess the potential of quantitative CT to detect characteristics linked to these bone fractures. However, the selected control group was argued to not be ideal, as it consisted of horses with pathologies related to the fetlock but did not contain sesamoid bone fractures. Addressing this issue remains a step for future research.

Data Collection and Analysis

• The data was collected using quantitative computed tomography (CT) to investigate any potential changes in bone morphology linked to fractures. The horses in the study were divided into two groups: horses with proximal sesamoid bone fractures, and control horses with no injuries related to the fetlock joint.
• The researchers then analyzed the CT results for indicators of higher bone density in the horses with fractures compared to those without fractures.
• Different diagnostic imaging studies were used as examples to highlight the complexity of selecting suitable controls for similar studies.

Results and Conclusions

• The results of the study show a potential for using CT as a clinical imaging technique to assess the risk of proximal sesamoid bone fracture in horses. However, there were issues with the control group selection that make these findings less than ideal.
• The researchers concluded that horses’ lameness is not an effective indicator of disease prevalence regarding these fractures, as many horses with significant microfractures can appear sound immediately prior to racing. This fact presents challenges in finding a suitable control group for these studies.
• They also noted the limitation of having to conduct studies post mortem and the need for approaches to enable live testing for practicality and better diagnostic accuracy. Here, the idea of a longitudinal study using advanced imaging is suggested, but the challenges and costs associated with such a study are also recognized.