Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
PLoS One. 2024 Jul 30;19(7):e0308061. doi: 10.1371/journal.pone.0308061. eCollection 2024.
A high proportion of horses in training, perceived as free from lameness by their owner, exhibit vertical movement asymmetries. These types of asymmetries are sensitive measures of lameness, but their specificity as indicators of orthopaedic pathology or locomotor function remains unclear. Equine athletes performing at a high level could be assumed to exhibit a higher degree of movement symmetry compared with the general horse population, but this has not been confirmed. This study investigated the prevalence of movement asymmetries in horses performing at a high level in three equestrian disciplines; show jumping, dressage and eventing, as well as the association between riders' perception of horse sidedness and said movement asymmetries. Using an inertial measurement unit-based system (Equinosis), gait analysis was performed on 123 high-performing horses. The mean difference between the two vertical minimum and between the two maximum values of each stride was recorded for the head (HDmin, HDmax) and pelvis (PDmin, PDmax). The horses were defined as asymmetric if one or multiple asymmetry parameters exceeded an absolute trial mean of: >6mm for HDmin or HDmax, and >3mm for PDmin or PDmax, with standard deviation less than the respective mean value. Based on the results, 70% of the horses were classified as asymmetric, which is similar to previous findings for young riding horses and horses competing at a lower level. More than one-third of these high-performing horses had asymmetry values of similar magnitude to those seen in clinically lame horses. No clear associations were observed between rider-perceived sidedness and the vertical movement asymmetry values, indicating that the perceived unevenness between sides is not a determinant of vertical movement asymmetry. Longitudinal studies on movement asymmetries in relation to training intensity and full clinical examinations with local or systemic analgesic testing are desired as further research to determine whether these movement asymmetries indicate a welfare problem.
训练有素的马匹中，相当一部分尽管其主人认为它们没有跛行，但仍表现出垂直运动的不对称性。这些类型的不对称性是跛行的敏感指标，但它们作为骨科病理或运动功能的指标的特异性尚不清楚。与一般马群相比，高水平运动的赛马可以假设表现出更高程度的运动对称性，但这尚未得到证实。本研究调查了在三项马术运动（障碍赛、盛装舞步和三项赛）中表现出色的马匹的运动不对称性的流行率，以及骑手对马的偏向感知与这种运动不对称性之间的关系。使用基于惯性测量单元的系统（Equinosis），对 123 匹表现出色的马进行了步态分析。记录了每个步幅的头部（HDmin、HDmax）和骨盆（PDmin、PDmax）的两个垂直最小值和两个最大值之间的平均值差异。如果一个或多个不对称性参数超过绝对试验平均值：HDmin 或 HDmax 超过 6mm，PDmin 或 PDmax 超过 3mm，且标准差小于相应的平均值，则将马匹定义为不对称。基于这些结果，70%的马匹被归类为不对称，这与之前对年轻骑乘马和低级别比赛的马的研究结果相似。这些表现出色的马中有超过三分之一的马的不对称值与临床上跛行的马相似。骑手感知的偏向与垂直运动不对称值之间没有明显的关联，表明感知到的两侧不均匀性不是垂直运动不对称的决定因素。需要进行关于运动不对称性与训练强度的纵向研究以及全面的临床检查，包括局部或全身镇痛测试，作为进一步的研究，以确定这些运动不对称性是否表明存在福利问题。
