Evaluation of the Effects of Chiropractic on Static and Dynamic Muscle Variables in Sport Horses

Abstract

The objective of this prospective controlled experimental study was to assess the effect of chiropractic on static bioimpedance (BI) and dynamic acoustic myography (AMG) of paired muscle groups in healthy sport horses. BI measures the passage of current through muscle and gives information relating to the degree of contraction, whereas AMG records and analyzes low-frequency sounds created during muscular activity. Bioimpedance and AMG recordings, in addition to subjective and objective gait analysis, were taken from 6 horses before and at 24, 48 and 72 hours after chiropractic treatment. Signs of gait asymmetry were detected objectively in all horses throughout the course of the study. BI: Bioimpedance scores for the left trapezius muscle were significantly altered at 24 and 72 hours. AMG: The balance score of the GM muscle at walk was significantly affected by time, as was its efficiency at the trot. This small pilot study reveals that some objective measurements of muscle function are altered following chiropractic, lasting for at least 72 hours after treatment. This warrants further investigations in a larger number of subjects and in additional muscle groups.