How accurate is a pressure plate as a clinical tool for equine gait evaluation?
MetadataShow full item record
Objective: The purpose of this project is to compare simultaneously recorded force plate (FP) and pressure plate (PP) measurements of sound horses at walk and trot to investigate whether limb-loading and timing data obtained from a stand-alone pressure plate system are highly correlated with force plate data. When parameters determined by a stand-alone pressure plate have an acceptable level of accuracy, they could be used interchangeable to force plate measurements and a possibility of using the pressure plate in a clinical setting would be created. Materials and Methods: Six healthy and clinically sound warm blood horses were walked and trotted over a running track, containing a build-in pressure plate, mounted on top of a force plate. For each horse five valid trails were recorded. A trail was considered valid if a complete print of one of the fore hooves was recorded and the velocity was within a preset range. For each set of 5 valid trials of both forelimbs, simultaneously collated FP and PP limb-loading and timing data (mean Peak Vertical Force (PVF), Vertical Impulse (VI), stance phase duration (ST), time on which the PVF occurs (tPVF) and forelimb symmetry ratios (SymPVF and SymVI)) are compared. Mixed Model Analysis of Variance and Bland-Altman plots were used to evaluate differences between FP and PP data for their statistical and clinical relevance. Results: Significant differences between FP and PP were seen for PVF, tPVF, VI, SymPVF and SymVI (P < 0,05), but not for ST. However, subsequent Bland-Altman analysis relativized the statistically significant differences for tPVF and for SymPVF and SymVI at trot as the Limits of Agreement were still within a range that might not be clinically relevant. Conclusion: A pressure plate can be useful for evaluating limb timing variables and symmetry ratios at trot in a clinical setting, although it cannot be used interchangeably to a force plate for measuring absolute values of limb loading. Nevertheless, it has important advantages in terms of practicality to unravel the load-distribution of the different portions of the hoof during a complete stance phase. With these advantages, it is tempting to explore the use of this equipment in the near future to quantify equine lameness in a clinical setting.