Correlation Between Acupuncture Point LI-18 and PC-1 Sensitivity and Front Hoof Surface Temperature in Horses Using Infrared Thermography

Abstract

The objective of this study was to determine whether acupuncture point sensitivity to palpation at LI-18 and PC-1 acupoints in horses was correlated with a difference in surface temperature between front hooves measured by highresolution infrared camera. Client-owned horses (n=41) presenting for traditional Chinese veterinary medicine (TCVM) exams for a variety of medical issues were recruited for convenience sampling. After 20 minutes of stall rest, bilateral front hoof thermography was performed in a designated stall. This was followed by bilateral acupoint scan (APS), where the outcome was considered positive (APS+) when an acupoint palpation, performed with an acupuncture needle guide tube (28 gauge, 2 inch), elicited a flinch response, or negative (APS-) when the palpation equaled no reaction. Based on the APS results, horses were grouped into 1) bilateral APS- outcome (bi-APS-) or 2) unilateral APS+ outcome (uni-APS+). Within each of the 2 groups mean temperature difference between front hoof surfaces was compared. The results showed that the bi-APS- group thermographic readings were not significantly different (p=0.551) between front hooves; however, the hoof temperatures were significantly different from each other in the uni-APS+ group (p=0.039). Study findings suggest that a horse’s APS sensitivity at LI-18 and/or PC-1 are correlated with thermographic imaging temperature of the front hooves. Further investigation and confirmation of these findings is needed along with further studies associating this temperature difference with hoof disorders for diagnostic investigations.