Clayton H M, Lanovaz J L, Schamhardt H C, Willemen M A, Colborne G R
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824-1314, USA.
Equine Vet J. 1998 Sep;30(5):384-9. doi: 10.1111/j.2042-3306.1998.tb04505.x.
The objective of this study was to provide normative data describing the net joint moments and joint powers for the stance phase of the forelimb in trotting horses. Kinematic and force plate data, synchronised in time and space, were collected for the right forelimb of 6 Warmblood horses moving at a trot. The 3-D kinematic data were collapsed onto a sagittal plane, and were combined with the vertical and longitudinal ground reaction forces and with segment morphometric data to calculate net joint moments in the sagittal plane across the distal interphalangeal (coffin), metacarpophalangeal (fetlock), carpal, elbow and shoulder joints. The joint mechanical power was calculated as the product of the joint moment and the joint's angular velocity. Major peaks on the moment and power curves were identified. Each joint showed consistent and repeatable patterns in the net joint moments and joint powers. During most of stance the net joint moment was on the caudal/palmar side of all joints except the shoulder. At the coffin joint the power profile indicated an energy absorbing function that peaked at 74% stance, which coincided with the maximal longitudinal propulsive force. The fetlock joint behaved as an elastic spring; energy was absorbed in the first half of stance as the flexor tendons and SL stored elastic energy, which was released in the second half of stance as a result of elastic recoil. The carpus did not appear to play an important role in energy absorption or propulsion. Both the elbow and shoulder joints showed what appeared to be phases of elastic energy storage and release in the middle part of the stance phase, followed by a propulsive function at the shoulder in the later part of stance. The fetlock, carpus and elbow showed virtually no net generation or absorption of energy. The net energy generation at the shoulder joint was approximately equal to the energy absorption at the coffin joint. In human subjects specific gait pathologies produce characteristic alterations in the shape of the power profile as well as changes in the amount of energy absorbed and generated at the joints. In horses evaluation of net joint moments and joint powers will further our understanding of the mechanics and energetics of lameness, and may prove to be a useful diagnostic tool. An understanding of the function and dysfunction of different anatomical structures will facilitate the interpretation of clinical findings in terms of mechanical deficits.
本研究的目的是提供规范性数据，描述小跑马前肢站立期的净关节力矩和关节功率。对6匹温血马右前肢在小跑时的运动学和测力板数据进行了时空同步采集。将三维运动学数据投影到矢状面上，并与垂直和纵向地面反作用力以及节段形态测量数据相结合，以计算跨远侧指间关节（蹄关节）、掌指关节（系关节）、腕关节、肘关节和肩关节矢状面的净关节力矩。关节机械功率计算为关节力矩与关节角速度的乘积。确定了力矩和功率曲线的主要峰值。每个关节在净关节力矩和关节功率方面均呈现出一致且可重复的模式。在站立期的大部分时间里，除肩部外，所有关节的净关节力矩均位于尾侧/掌侧。在蹄关节处，功率曲线表明其具有能量吸收功能，在站立期74%时达到峰值，这与最大纵向推进力相吻合。系关节表现为一个弹性弹簧；在站立期的前半段，随着屈肌腱和悬韧带储存弹性能量，能量被吸收，而在站立期的后半段，由于弹性回弹，能量被释放。腕关节在能量吸收或推进方面似乎未发挥重要作用。肘关节和肩关节在站立期的中部均呈现出弹性能量储存和释放的阶段，随后在站立期后期，肩部发挥推进功能。系关节、腕关节和肘关节几乎没有净能量产生或吸收。肩关节的净能量产生大致等于蹄关节的能量吸收。在人类受试者中，特定的步态病理会导致功率曲线形状的特征性改变以及关节处吸收和产生的能量量的变化。在马匹中，评估净关节力矩和关节功率将有助于我们进一步了解跛行的力学和能量学原理，并且可能被证明是一种有用的诊断工具。了解不同解剖结构的功能和功能障碍将有助于根据机械缺陷来解释临床发现。
