Research Paper
A pilot study of the effects of acupuncture treatment on objective and subjective gait parameters in horses

https://doi.org/10.1111/vaa.12373Get rights and content

Abstract

Objectives

To investigate whether acupuncture can alter gait in horses as assessed by objective and subjective parameters.

Study design

Prospective, randomized, singleblinded, crossover study.

Animals

Eight adult horses.

Methods

Horses were randomly assigned to a treatment (three acupuncture treatments in 8 days) or control group. Subjective and objective gait analyses were performed before and after each treatment and at 1, 3 and 7 days after the last treatment (time-points 1–9, respectively). Horses were assessed at the trot in a straight line on a hard surface and on the lunge on the left and right reins on a soft surface (conditions 1–3, respectively). After 12 weeks, groups were reversed. Objective gait analysis was performed using inertial sensors and subjective analysis by two board- certified surgeons who reviewed video-recordings. Each limb was assessed for lameness before and after treatment. Lameness and global scores were assigned using 4-point scales. Assessors were blinded to treatment status. The effects of treatment (yes/no), time (1–9) and horse under conditions 1 –3 were compared using a linear mixed-effects model and a generalized estimating equation.

Results

Treatment decreased hip hike difference under all conditions [condition 1: control, 6.3 ± 6.4 mm versus treatment, –0.2 ± 6.4 mm (p = 0.007); condition 2: control, 9.7 ± 7.8 mm versus treatment, 2.8 ± 7.8 mm (p = 0.032); condition 3: control, 7.3 ± 6.3 mm versus treatment, –2.7 ± 6.4 mm (p = 0.003)]. Other parameters also improved significantly under conditions 1 and 3. Based on subjective gait analysis, treatment decreased lameness [odds ratio (OR) 0.51, 95% confidence interval (CI) 0.34–0.78; p = 0.002] but not global (OR 0.53, 95% CI 0.24–1.10; p = 0.12) scores.

Conclusions and clinical relevance

Acupuncture can change horses' gaits to a degree appreciable by objective and subjective analyses.

Introduction

Acupuncture, which is part of traditional Chinese medicine, is increasingly incorporated into human and veterinary medicine. Traditional techniques have been adopted worldwide and numerous variations of acupuncture therapy have been developed. The mechanisms of action are still not fully understood. However, the use of modern investigation tools, including sophisticated imaging techniques, has suggested that acupuncture triggers a sequence of events involving the release of endogenous opioid- like substances, such as enkephalin, endorphin and endomorphin, which are measurable in plasma and cerebrospinal fluid, and which modulate pain signals (Wang et al., 2008, Kawakita and Okada, 2014). The limbic system has also been shown to play an important role in acupuncture-induced analgesia (Wang et al. 2008).

Although acupuncture is used in the treatment of a wide variety of diseases in people and veterinary species (Mittleman and Gaynor, 2000, Schofield, 2008, Yin and Chen, 2010, de Fourmestraux et al., 2014, Pfab et al., 2014), one of its most common applications is in the management of chronic pain, often arising from the musculoskeletal system. Large-scale clinical trials in people have demonstrated the efficacy of acupuncture in the treatment of lower back pain compared with standard care or patients not currently being treated (Brinkhaus et al., 2006, Haake et al., 2007). Over the last decades, acupuncture has been increasingly incorporated into equine medicine, but controlled clinical trials investigating its efficacy remain sparse. Anecdotally, acupuncture has been reported to be successful in alleviating a variety of painful orthopaedic conditions, particularly back pain. However, the assessment of treatment failure or success is often subjective and influenced by the owner's and the attending veterinarian's expectations. The lack of controlled studies in which objective assessments are made has led to continued scepticism about whether acupuncture has any effects at all in horses (Ramey 2005). This pilot study tested the hypothesis that acupuncture treatment would result in alterations in gait in horses and that these would be appreciable by objective and subjective gait analyses.

Section snippets

Materials and methods

Authorization was granted by the Ethics and Welfare Committee of the Royal Veterinary College, London (URN approval no. 2013 1244). Eight systemically healthy horses, as determined by physical examination (performed by BD) that belonged to the Royal Veterinary College Equine Referral Hospital teaching and blood donor herd were used. The number of horses was based on those in similar studies that demonstrated treatment effects with four to eight animals per group (Xie et al., 2001, Xie et al.,

Data analyses

Data were analysed using IBM spss for Windows Version 19.0 (IBM Corp., NY, USA). Normality of the data was assessed by the inspection of histograms. Objective gait assessments are presented as the mean ± standard error. Comparisons between subjective lameness scores are expressed as odds ratios (ORs) and 95% confidence intervals (CIs). Data for each of the three conditions were analysed separately. Baseline objective and subjective gait analyses data (T1) from the treatment and control groups

Results

Two Irish Sports horses, two ponies and four trotters (two geldings and six mares) with a mean ± standard deviation age of 14.8 ± 5.3 years were included in the study. Acupuncture treatment was well tolerated by all horses except that in one horse the insertion of the needle at one specific point resulted in violent shaking and foot stamping. This point was left untreated during all treatment sessions. One horse developed a foot abscess between T8 and T9 while serving as a control and was not

Discussion

To the authors' knowledge, this is the first prospective, single-blinded, crossover study to evaluate the effects of acupuncture treatment on movement parameters in horses. The study was conducted as a pilot study to address the basic question of whether or not acupuncture treatment has any appreciable effect on gait in horses. Encouragingly, treatment effects were demonstrated for at least one objectively assessed pelvic limb parameter under all conditions and for all pelvic limb parameters

Acknowledgements

The authors would like to thank Amy Martin, Clinical Science and Services, The Royal Veterinary College for her help with the objective gait analysis.

References (27)

  • C. de Fourmestraux et al.

    Multimodal therapy including electroacupuncture for the treatment of facial paralysis in a horse

    Equine Vet Educ

    (2014)
  • B. Gerdle et al.

    Chronic musculoskeletal pain: review of mechanisms and biochemical biomarkers as assessed by the microdialysis technique

    J Pain Res

    (2014)
  • M. Haake et al.

    German Acupuncture Trials (GERAC) for chronic low back pain: randomized, multicenter, blinded, parallel- group trial with 3 groups

    Arch Intern Med

    (2007)
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