Functional Electrical Stimulation (FES) and the Effect on Equine Multifidi Asymmetry.

This study indicates that Functional Electrical Stimulation (FES) has a significant impact on improving the symmetry of equine thoracolumbar multifidi – a factor linked to back pain in horses. This treatment could help improve spinal function and reduce back pain in horses.

Understanding the Research

• The research’s main objective was to identify whether FES influences the symmetry of equine thoracolumbar multifidi. This was motivated by previous studies that linked multifidi asymmetry to back pain in horses and humans.
• The research team conducted a study with 12 horses who received FES treatment for 8 weeks. Another 12 horses were kept as control subjects and did not receive any FES treatments. The researchers measured the cross-sectional area (CSA) of the multifidi in the treated horses at seven different thoracolumbar levels and then compared the left-to-right asymmetry before and after FES treatment.
• The same measurements were taken over the same period in the control group. To avoid bias, all evaluations were done blindly, i.e., without knowing whether the horse received FES treatment or not.
• They used statistical tests to evaluate the data, including the two-sided, matched-pairs t-tests, and Welch’s t-test (for assessing differences in groups with unequal variances). The Sidak correction method was also applied to account for multiple comparisons.

Findings

• The study found a significant improvement in the symmetry of multifidi in horses after FES treatment at all seven thoracolumbar levels.
• No improvement was found in the control group, further enforcing the positive impact of FES treatment.
• The mean difference in improvements between the treatment and control groups was found to be statistically significant, confirming the efficacy of FES in improving equine multifidi symmetry.
• The change in symmetry was due to combinations of increases, decreases, and maintenance of the CSA of the left and right multifidi. This suggests complex mechanisms of action involved in the FES treatment’s effectiveness.
• The study underscores the potential of the applied FES protocol in improving spinal function and hence, possibly aiding in relieving back pain in horses.