The influence of lameness on equine stride length consistency.

This study investigates how lameness in horses affects the consistency of their stride length. It found that horses with orthopaedic pain tend to maintain lower stride variability, likely as a compensation technique to minimise pain in the affected limb.

Objective and Methodology

• The main objective of this study was to examine the effect of orthopaedic pain on the variation of stride length in horses suffering from forelimb lameness.
• A total of 21 horses with forelimb lameness were used in the study.
• Data was collected when the horses were trotting on a treadmill for at least 12 motion cycles, before and after the administration of intra-articular or perineural anaesthesia.
• Stride length was measured for each motion cycle, and the average and standard deviation were determined for each condition.

Findings

• Lameness in the forelimb was quantified as the percentage of asymmetry in vertical head movement.
• The researchers observed that the application of regional anaesthesia resulted in a significant reduction of forelimb lameness. In parallel with this decrease in lameness, there was a significant increase in the standard deviation of stride length (+0.35%, P< 0.05).

Interpretation

• The results indicate that horses experiencing orthopaedic pain maintain a relatively low variability in their stride length.
• This could be because the lame horse adopts an optimal compensatory mechanism to ease the pain in the affected limb, and any deviation from this pattern potentially amplifies the pain.
• The findings suggest that stride variability in horses could serve as a valuable diagnostic tool to assess pain or discomfort due to lameness. However, further research is required to validate this hypothesis.