Comparison of an inertial sensor system with a stationary force plate for evaluation of horses with bilateral forelimb lameness.

The study compares an inertial sensor system with a stationary force plate for assessing lameness in horses. It finds the inertial sensor system to be a highly sensitive method for detecting differences in the severity of lameness in the forelimb, affirming its usefulness for clinical use and suggesting the need for further studies to evaluate its specificity.

Methods

• This study involved 18 adult horses exhibiting bilateral forelimb lameness.
• These horses were fitted with inertial sensors and assessed for lameness as they trotted in a straight line over a stationary force plate.
• The researchers took measurements for vertical head movement asymmetry (HMA) and the vector sum (VS) of maximum and minimum head height differences during both halves of the horse’s stride.
• These measurements were used to predict differences in peak vertical force (PVF), a measure of lameness, as a percentage of the horse’s body weight between the right and left forelimbs. The repeatability of each of these variables was also compared using the intraclass correlation coefficient (ICC).
• The findings from the inertial sensor system were validated using a stationary force plate, considered the gold standard in such assessments.

Results

• The study found that the standard errors in predicting the difference in PVF between the right and left forelimbs using HMA and VS measurements were only 6.1% and 5.2%, respectively, indicating a high level of accuracy.
• Repeatability was strong for PVF (ICC, 0.86) and VS (ICC, 0.84), though less so for HMA (ICC, 0.72).
• There were significant positive correlations between HMA (R(2) = 0.73) and VS (R(2) = 0.81) and the difference in PVF between the right and left forelimbs, indicating that as either HMA or VS increase, so does the PVF, hence the severity of lameness.
• The success rate in correctly classifying which forelimb was more severely affected based on HMA and VS was 83.3% and 77.8% respectively.

Conclusions

• The study found the inertial sensor system to be a highly sensitive tool for detecting and assessing the severity of forelimb lameness in horses.
• This suggests that the system has strong clinical potential for use in equine veterinary settings.
• However, the authors also suggest that further studies are required to assess the specificity of the system or how accurately it can identify non-lameness.