Repeatability of gait pattern variables measured by use of extremity-mounted inertial measurement units in nonlame horses during trotting.

This study validates the use of extremity-mounted inertial measurement units (IMUs) in measuring the repeatability of gait variables in non-lame horses trotting on a treadmill. The results demonstrate a high degree of consistency over time, suggesting that this method could be a reliable tool for gait analysis in horses.

Research Design and Procedure

• The study was conducted on 10 non-lame horses, using six extremity-mounted IMUs attached to specific parts (metacarpal, metatarsal, and distal tibial regions) of each horse.
• Data were gathered in a standard fashion over a three-week period, making three measurements per day, three days per week, while the horses were trotted on a treadmill.
• Each measurement session comprised a minimum of 20 strides, from which at least 10 were chosen for the analysis. The assessment pooled spatial and temporal variables acquired from the IMUs.

Analytical Approach

• Repeatability coefficients, calculated based on the within-subject standard deviation, were computed for each gait analysis variable each week.
• The paper reports that the majority of temporal and spatial variables showed high repeatability (repeatability coefficients less than 10) across the three weeks of data collection.
• A small number of spatial variables, specifically symmetry variables (which were calculated from other variables), demonstrated marginally higher repeatability coefficients (i.e., lower repeatability) only in the concluding week.

Results and Conclusion

• Apart from some symmetry variables, the gait data collected using the extremity-mounted IMUs showed high repeatability for the horses trotting under controlled treadmill exercise conditions.
• The paper concludes that such IMUs provide a consistent measure of both the spatial relationship between two adjoining segments (joint angles) and the temporal relationship among all segments (limb phasing).
• This level of repeatability suggests that extremity-mounted IMUs may offer a viable method for detailed gait analysis in horses.

Clinical Relevance

• The study has important clinical implications, as gait analysis is a critical component in diagnosing and treating lameness issues in horses.
• The consistent and reliable data obtained via extremity-mounted IMUs could enhance the precision and efficiency of these diagnoses.
• Moreover, this technique may lead to better treatment outcomes, by yielding a more accurate understanding of a non-lame horse’s gait under controlled conditions.