Willemen M A, Jacobs M W, Schamhardt H C
Equine Biomechanics Research Group, Utrecht University, The Netherlands.
Equine Vet J Suppl. 1999 Jul(30):245-8. doi: 10.1111/j.2042-3306.1999.tb05227.x.
An in vitro model was developed and validated in vivo to quantify the attenuation of impact vibrations, transmitted through the lower equine forelimb and to assess the effects of horseshoeing on this attenuation. The transsected forelimbs of 13 horses were equipped with custom-made hollow bone screws in the 4 distal bones, on each of which a tri-axial accelerometer could be mounted. The limbs were then preloaded while the impact was simulated by dropping a weight on the steel plate on which the hoof was resting. At the hoof wall, the distal, middle and proximal phalanx and at the metacarpal bone, the shock waves resulting from this impact were quantified. To assess the damping effects of shoeing, measurements were performed with unshod hooves, hooves shod with a normal flat shoe and hooves shod with an equisoft pad and a silicone packing between hoof and pad. The in vitro model was validated by performing in vivo measurements using one horse, and subjecting the limb of this horse to the same in vitro measurements after death. Approximately 67% of the damping of impact vibrations took place at the interface between the hoof wall and the distal phalanx. The attenuation of impact vibrations at the distal and proximal interphalangeal joints was considerably less (both 6%), while at the metacarpophalangeal joint 9% of the amplitude of that at the hoof wall was absorbed, leaving approximately 13% of the initial amplitude at the hoof wall detectable at the metacarpus. Compared to unshod hooves the amplitude at the hoof wall is 15% higher in shod hooves. No differences could be observed between shoe types. At the level of the first phalanx and metacarpus the difference between shod and unshod vanished; it was therefore concluded that, although shoeing might influence the amplitude of impact vibrations at the hoof wall, the effect of shoeing on the amplitude at the level of the metacarpophalangeal joint is minimal.
开发了一种体外模型并在体内进行了验证，以量化通过马的前肢下部传递的冲击振动的衰减，并评估钉蹄对这种衰减的影响。13匹马的断肢在4块远端骨骼中安装了定制的空心骨螺钉，每根螺钉上都可以安装一个三轴加速度计。然后对肢体进行预加载，同时通过将重物落在蹄子所放置的钢板上来模拟冲击。在蹄壁、远节指骨、中节指骨和近节指骨以及掌骨处，对这种冲击产生的冲击波进行了量化。为了评估钉蹄的减震效果，分别对未钉蹄、钉普通平底蹄铁的蹄子以及钉有Equisoft垫且蹄子与垫子之间有硅胶填充物的蹄子进行了测量。通过对一匹马进行体内测量并在其死后对该马的肢体进行相同的体外测量，验证了该体外模型。大约67%的冲击振动衰减发生在蹄壁与远节指骨之间的界面处。远节指间关节和近节指间关节处的冲击振动衰减要小得多（均为6%），而掌指关节处吸收了蹄壁处振幅的9%，在掌骨处可检测到的初始振幅约为蹄壁处的13%。与未钉蹄相比，钉蹄的蹄壁处振幅高15%。不同蹄铁类型之间未观察到差异。在第一指骨和掌骨水平，钉蹄和未钉蹄之间的差异消失；因此得出结论，尽管钉蹄可能会影响蹄壁处冲击振动的振幅，但钉蹄对掌指关节水平振幅的影响很小。
