Electroacupuncture as a treatment for suspected trigeminal nerve-mediated head-shaking in 42 horses

Abstract

Background: Electroacupuncture (EA) has been used successfully as a treatment for trigeminal nerve-mediated head-shaking (TMHS) in a small case series, but results from a larger number of cases are lacking. Objectives: To retrospectively investigate the effectiveness of EA as a treatment for horses with TMHS. Study Design: A multicentre retrospective case series of 42 horses (179 treatments). Methods: Data collected included signalment, history, duration and severity of TMHS (expressed as grades using a previously published scale from 0 to 3), diagnostic tests performed, number of EA treatments and effect of treatment as perceived by the owner or primary veterinarian. Information was retrieved from clinical records of horses treated for TMHS with EA between 2015 and 2024 by one of the participating veterinarians. The owners or primary veterinarian was contacted for follow-up information, and the grades of head-shaking before the first and after the last treatment were compared. Results: The procedure was well tolerated by all horses, and EA caused a significant improvement in head-shaking grades when comparing grades before (median grade 3; range: 1–3) and after treatment (median grade 1; range: 3–0; p < 0.001). Sixty-four per cent (n = 27) of cases showed an improvement of TMHS after their final treatment, with complete resolution of signs seen in 14 horses (33%). No improvement was seen in 31% (n = 12) of cases, and two horses (4.8%) experienced worsening of clinical signs post-treatment, with one being temporary and the other remaining at a higher grade. No other complications were noted. Main Limitations: Retrospective study with a small number of cases and no placebo or control group relying on owner assessment. Strict, uniform diagnostic criteria for TMHS were not specified. Conclusions: EA was well-tolerated with minimal complications arising, and improvement was seen in 64% of horses. Refinement of the EA technique over time might lead to a higher success rate and longer remission periods.