Bergmann G, Graichen F, Rohlmann A
Oskar-Helene-Heim, Department of Orthopaedics, Free University of Berlin, Germany.
J Biomech. 1999 Aug;32(8):769-77. doi: 10.1016/s0021-9290(99)00068-8.
Testing orthopaedic implants at the proximal femur of sheep requires knowledge of the contact forces acting on this joint. Telemeterized implants were used for long-term measurements of these forces in four sheep, mostly during treadmill walking. Joint forces in the same sheep varied widely from day to day and interindividual differences were also pronounced. Forces during walking were mostly higher than in previous short-term measurements. At medium walking speed, loads in the range of 65-140% of the body weight were typical. Fast walking increased the forces by only 20%, compared to slow speed. Stomping on the ground at the beginning of the stance phase and starting to run freely led to very high forces. The highest values observed were nearly four times the body weight. As in humans, the directions of high forces varied only slightly in the frontal plane throughout the whole stance phase but much more in the transverse plane. With regard to the force magnitudes and their directions, sheep seem to be a good model for testing human implant at the proximal femur.
在绵羊股骨近端测试骨科植入物需要了解作用于该关节的接触力。遥测植入物用于对四只绵羊的这些力进行长期测量,主要是在跑步机行走期间。同一只绵羊的关节力每天变化很大,个体间差异也很明显。行走时的力大多高于之前的短期测量值。在中等步行速度下,典型的负荷范围为体重的65%-140%。与慢速行走相比,快速行走时力仅增加20%。在站立阶段开始时跺脚并开始自由奔跑会导致非常高的力。观察到的最高值几乎是体重的四倍。与人类一样,在整个站立阶段,高力的方向在额平面上变化很小,但在横平面上变化更大。就力的大小及其方向而言,绵羊似乎是测试人类股骨近端植入物的良好模型。