Reasons for performing study: Equine ataxia is routinely evaluated subjectively by clinicians; however, objective measurements of the movement and coordination of ataxic horses have not been reported.
Objectives: To document the movement pattern of ataxic horses and compare the results to the movement of neurologically sound horses with, and without, sedation.
Methods: Seventeen ataxic horses were evaluated walking and trotting on a treadmill using a 3D high speed video system. From the horizontal movement of hoof markers the autocorrelation function (ACF) of the left forelimb and the cross correlation function (CCF) between the left forelimb and other 3 limbs (CCF foreleft/hindright [flhr], foreleft/hindleft [flhl], foreleft/foreright [flfr]) was calculated. This resulted in a value of motion cycle consistency. The results were compared to data of 17 neurologically normal horses with, and without, sedation with detomidine. For statistical analysis the t test for independent samples was used.
Results: Comparing normal (NO) and ataxic (AT) horses at the walk, highly significant differences for the ACF and for all the CCFs were documented. At the trot, ACF and CCFs flhr and flfr were significantly different in the NO and AT groups. Comparing sedated and ataxic horses, only the CCF flfr at walk and at trot were significantly different.
Conclusion and potential relevance: Ataxia is best documented and examined at the walk. At trot pendulum effect may make coordination easier for horses. The results of this study serve as basic data for evaluating questionably ataxic horses.