Contribution of dynamic calibration to the measurement accuracy of a pressure plate system throughout the stance phase in sound horses.

This research aims to measure the accuracy of a pressure plate system for horses using dynamic calibration. The highlighting point of the study is the crucial need for optimizing calibration to improve measurement accuracy, something that is especially needed at high impact and breakover phases of a horse’s stance.

Objective and Methodology

• The study’s main goal was to examine the accuracy of a pressure plate (PP) system for assessing a horse’s stance by using dynamic calibration with a force plate (FP). This was done using six healthy Warmblood horses.
• The horses were made to walk and trot over a combined PP-FP system, sampled at a rate of 250 Hz. Five valid measurements were taken for each forelimb.
• The recalibration factor (RF), the ratio between the calibrated and raw PP data, was measured throughout the horse’s stance phase.

Findings and Importance of Dynamic Calibration

• The findings showed that the vertical force curve of the PP exhibited a biphasic pattern at the walk and typical spikes at the start and end of the stance at the trot after dynamic calibration.
• During both walk and trot phases, the RF was discovered to be higher and more variable at the onset (the impact phase) and the final part of the stance (the breakover phase).
• Between these phases – during the support phase – the RF was observed to be lower and relatively constant.
• The RF as a function of the vertical force and the RF in the loading part of the vertical force curve was lower than in the unloading part, further substantiating the findings.
• The research underlines the importance of dynamic calibration of the PP with an FP. Without it, the measurement accuracy of the PP, especially in the impact and breakover phases, was found to be suboptimal.
• Nevertheless, the study found out that the accuracy during the support phase was relatively high and constant. Thus, higher loading did not increase the deviation.

Implications and Conclusions

• The results of the study emphasize the importance of optimizing the calibration of the PP as this could potentially reduce systematic measuring errors.
• In a clinical setting, these errors can be neutralized by evaluating the left-right symmetry ratios when a stand-alone PP is used to quantify locomotor symmetry objectively.
• Therefore, this research gives significant insights into optimizing measurement strategies when using pressure plates for evaluating the stances of horses, which is crucial for determining their health and performance.