Pressure Plate Evaluation of Forelimb Toe‐Heel and Medio‐Lateral Hoof Balance on a Hard Versus a Soft Surface in Sound Ponies at the Walk and Trot

Abstract

IntroductionPressure plate analysis has been limited to measurements on a hard surface, whereas horses routinely perform on a soft substrate.MethodsFive sound unshod ponies were walked and trotted over a pressure plate under 2 different conditions: first, the plate was covered with a 5‐mm rubber mat, and then with an additional 50‐mm layer of sand/synthetic fibres. Peak vertical force (PVF), vertical impulse (VI), peak vertical pressure (PVP), contact area (CA) and stance duration (ST) were obtained. Toe‐heel and medio‐lateral hoof balance curves of the vertical force were calculated (126 Hz). Hard vs. soft surfaces were compared using ANOVA and Kruskall‐Wallis test with pairwise comparisons.ResultsPVF, VI, PVP and ST decreased on the soft substrate, while CA increased (P<0.001). At impact, there was more even load distribution between the toe and heel region on the soft vs. hard surface, both at walk (P<0.001) and trot (P = 0.039), and between the lateral and medial zone at walk (P = 0.006), but not at trot. At mid‐stance, there was more loading of the toe region on the soft vs. hard surface at walk (P = 0.044) and at trot (P = 0.005), while the medial and lateral zone were loaded equally.ConclusionsThe differences observed may be due to dampening effects, measurement errors or gait adaptations. Due to the lack of simultaneous force plate data this cannot be definitively identified, but the first option seems most likely. This study opens perspectives for evaluation of the effects of conformational deficits and therapeutic farriery on hoof loading in relation to arena composition.Ethical Animal ResearchAll ponies in the study are part of the faculty teaching herd, institutional guidelines were followed. Sources of funding: Ghent University. Competing interests: none.