Validation of a novel instrumented hoof boot with pressure sensors using force plate gait kinetics in horses at walk and trot

Abstract Background Force plates (FP) are considered the gold standard for quantitative equine gait evaluation but are limited to experimental use. An instrumented hoof boot (IHB) with pressure sensors and an inertial measurement unit would allow clinicians to objectively assess kinetic parameters and gait symmetry. Objectives To validate the IHB by comparing kinetic parameters with obtained FP data. Study Design In vivo experiments. Methods Twenty‐seven horses were measured with IHBs on FPs at walk and trot. Mean value kinetic parameters recorded were: (1) peak vertical force (PVF) [N/kg]/peak vertical pressure (PVP) [N/kg]; (2) vertical impulse (AUC) [Nms/kg]; (3) peak loading rate (PLR) [N/ms]; (4) stance duration (StD) [ms] and (5) time of peak vertical force (TPVF) [%stance]/time of peak vertical pressure (TPVP) [%stance]. Agreement and correlation were assessed using Bland–Altman analysis and Kendall's correlation coefficient τ . Significance level was set at α  = 5%. Results Bland–Altman plots showed an overall moderate to good agreement with following mean difference (bias) and 95% limits of agreement (95%LoA) for IHB and FP: PVF/PVP [N/kg] walk: bias −0.197 (95%LoA: −0.786 to 0.392), trot: bias 0.0516 (95%LoA: −1.01 to 1.11), AUC [Nms/kg] walk: bias −80 (95%LoA: −420 to 260), trot: bias −44.4 (95%LoA: −291 to 202), PLR [N/ms] walk: bias 0.467 (95%LoA: −0.582 to 1.52), trot: bias 6.24 (95%LoA: −0.675 to 13.2), StD [ms] walk: bias 60.4 (95%LoA: −6.36 to 127), trot: bias 28.7 (95%LoA: −1.47 to 58.8), TPVF/TPVP [%stance] walk: bias −1.72 (95%LoA: −8.28 to 4.83), trot: bias −2.8 (95%LoA: −6.43 to 0.832). Correlations were very strong to fair positive. Main Limitations Small, mixed‐breed population, pending repeatability study, ex vivo calibration on manufacturers' behalf. Conclusions The IHB is a portable, quick method for kinetic gait analysis that approximates the gold standard FP, offering a promising tool for future clinical use.