Accelerometer-based system for the detection of lameness in horses.

Video-based kinematic analysis of gait in horses is accurate for quantification of lameness and reliable for identification of the affected limb. Algorithms for the measurement of the vertical head and pelvic displacement and phase correlation with vertical displacement of one forelimb and hindlimb foot have been developed for this purpose. However, because of camera field-of-view limitations, video-based analysis of gait can only be reliably accomplished with the horse constrained to move on a treadmill. This paper describes the use of 2 single-axis accelerometers and 2 gyroscopic transducers as a measurement system for the identification and quantification of forelimb and hindlimb lameness in horses. Vertical head and pelvic acceleration are converted to displacement, lameness is quantified from previously developed algorithms, and affected limb is determined by correlation of head and pelvic signals with gyroscopic signals from the right forelimb and hindlimb feet. Signals from the 4 transducers are telemeterized at 200 Hz and collected to a receiver connected to a lap top computer, freeing the horse from the constraints of a treadmill laboratory setting. In this paper we describe the reliability of this new accelerometer-based system in horses with induced lameness while trotting on a treadmill and freely outside overground.