Back W, Schamhardt H C, Barneveld A
Department of General and Large Animal Surgery, Utrecht University, The Netherlands.
Equine Vet J Suppl. 1997 May(23):80-3. doi: 10.1111/j.2042-3306.1997.tb05060.x.
The canter is a 3 beat asymmetrical gait with a difference in timing between left and right limbs. To evaluate intralimb asymmetry at the canter, a group of 24 Dutch Warmbloods was evaluated on a treadmill (7 m/s) using a modified CODA-3 optoelectronic gait analysis system. Thirteen horses cantered in the left lead ('leading limb' group) and 11 in the right lead ('trailing limb' group) during left forelimb recordings, while 11 horses were at the left and 13 were at the right lead during left hindlimb recordings. Kinematic differences between horses from the 'leading limb' and 'trailing limb' group were statistically evaluated at a significance level of P<0.05. Stride, stance and swing duration were similar between the 2 groups. The pelvis rotation, angle of maximal protraction and total range of maximal pro- and retraction were larger in the 'leading limb' group, while the scapula rotation, and the angle of maximal retraction were larger in the 'trailing limb' group. The elbow and hip joints were more flexed at impact, at maximal extension and at maximal flexion of the leading limb, whereas the stifle joint was more extended at impact. Furthermore, the leading tarsal joint was more maximally flexed in stance and swing phase, whereas the carpal joint was more flexed only in the swing phase of the leading limb. However, during the stance phase the maximal fetlock extension of the trailing fore- and hindlimbs were significantly larger. Apparently, horses move at the canter with a more protracted leading limb by more flexing the elbow, carpal, hip and tarsal joints. In the trailing limb, however, the scapula is more rotated, and the tarsal and fetlock joints are more loaded. In conclusion, the difference in interlimb timing between left and right limbs at canter also leads to an asymmetry in intralimb coordination of these limbs.
跑步是一种三拍不对称步态，左右肢体的时间存在差异。为了评估跑步时肢体内部的不对称性，使用改良的CODA-3光电步态分析系统在跑步机上（7米/秒）对一组24匹荷兰温血马进行了评估。在左前肢记录期间，13匹马以左前肢领先跑步（“领先肢体”组），11匹马以右前肢领先跑步（“跟随肢体”组）；而在左后肢记录期间，11匹马以左前肢领先，13匹马以右前肢领先。对“领先肢体”组和“跟随肢体”组马匹之间的运动学差异进行了统计学评估，显著性水平为P<0.05。两组之间的步幅、站立和摆动持续时间相似。“领先肢体”组的骨盆旋转、最大前伸角度以及最大前伸和后缩的总范围更大，而“跟随肢体”组的肩胛骨旋转以及最大后缩角度更大。在领先肢体的着地、最大伸展和最大屈曲时，肘关节和髋关节更屈曲，而膝关节在着地时更伸展。此外，领先跗关节在站立和摆动阶段最大程度地屈曲，而腕关节仅在领先肢体的摆动阶段更屈曲。然而，在站立阶段，跟随前肢和后肢的最大球节伸展明显更大。显然，马匹在跑步时通过更多地屈曲肘关节、腕关节、髋关节和跗关节，使领先肢体更加伸展。然而，在跟随肢体中，肩胛骨旋转更多，跗关节和球节承受的负荷更大。总之，跑步时左右肢体间时间的差异也导致了这些肢体内部协调的不对称。
