Quantitative assessment of gait parameters in horses: Useful for aiding clinical decision making?

Abstract

SummaryGait analysis in horses has moved from the laboratory into the outside world enabling researchers and clinicians to make use of quantitative measurements to provide evidence aiding clinical decision making. In this article we explain how the two major visual signs of lameness – head nod and hip hike –are linked to the mechanics of lameness. These parameters should be regarded as well suited for incorporation into clinical decision making being easily measurable e.g. with inertial sensors under nonlaboratory conditions and representative of the underlying mechanical changes. A brief overview of the results of validation studies of the use of inertial sensors for quantification of movement symmetry shows that accuracy, precision and repeatability with current sensor generations are in the order of 3–7 mm; this is below the reported detection threshold for movement symmetries ‘by eye’. Recent studies with inertial sensors have investigated conditions relevant to the clinical lameness examination: lungeing, flexion tests and diagnostic analgesia. Lungeing introduces kinematic adaptations rendering head and pelvic movement asymmetrical, even in sound horses. First guideline values are available for changes after flexion tests and diagnostic analgesia, and we understand which parameters show consistent changes. This is crucial for investigating the effects in horses with different orthopaedic deficits. In conclusion, the current inertial sensor systems, while not quantifying all the gait adaptations seen in lame horses, characterise the major mechanical changes affecting fore‐ and hindlimb lame horses. In order to avoid misinterpretation of the generated data, users should have a thorough understanding of the gait parameters and be aware of sensor limitations in terms of accuracy, precision and repeatability.