The use of a panning camera technique in equine kinematic analysis

Summary A method applicable for field studies of equine locomotion based on recordings by high-speed cinematography/videography with a panning camera is presented. A ground reference plane/line was defined by a number of ground reference plates at equidistant intervals along the filming range. One ground reference plate in the middle of the range was predefined and designated as Ref0. The camera position was determined in such a way that the camera axis was perpendicular to the reference line when aiming towards Ref0. The maximum error introduced by the experimental setup was less than 3% and the perspective errors at the end of the recording range less than 0.02 m in a single position determination. The method was applied to study some basic temporal and linear variables and the pastern, metacarpal segment and fetlock joint angles in 6 young Standardbred trotters at 10.2 ± 0.17 m/s. The mean stride and stance durations for the group of horses were 503 ± 15 ms and 131 ± 6 ms, respectively. Indications of laterality in individual horses were observed when diagonal and contralateral pairs of limbs were studied. Sudden angle changes were observed in the fetlock segment and fetlock joint at full support following braking of the fore-aft horizontal hoof movement.