Olmstead T G, Wevers H W, Bryant J T, Gouw G J
J Biomech. 1986;19(8):565-77. doi: 10.1016/0021-9290(86)90162-4.
Quantitative changes in valgus/varus knee stability with different levels of muscular activity were determined for five subjects. A specially designed machine was used to measure resistance to angulation in the frontal plane. This device held the thigh stationary, the knee straight, an cycled the leg from side to side at a constant rate between present moment limits. Resistance to this forced valgus/varus motion was measured simultaneously with torque about the knee in the sagittal plane. Muscle activity was monitored by electromyography (EMG). Direct comparison of moment-rotation characteristics allowed changes in stability to be quantified as a function of extension and flexion torque. Extension torques less than 20% of the maximum increased varus stability more than valgus stability. Flexion torques of the same relative magnitude increased valgus stability more than varus stability. Comparison with the literature suggested that prevention of opening of the lateral side of the joint under varus loading was responsible for increased varus stability with increasing torque, both with extension and flexion torques.
针对五名受试者，测定了不同肌肉活动水平下膝内翻/外翻稳定性的定量变化。使用一台专门设计的机器来测量额状面内的抗角度变化阻力。该装置固定大腿，保持膝关节伸直，并以恒定速率在当前时刻限制之间使腿部左右循环摆动。同时测量对这种强制内翻/外翻运动的阻力以及矢状面内围绕膝关节的扭矩。通过肌电图（EMG）监测肌肉活动。力矩-旋转特性的直接比较使得稳定性的变化能够被量化为伸展和屈曲扭矩的函数。小于最大扭矩20%的伸展扭矩增加内翻稳定性的程度大于外翻稳定性。相同相对大小的屈曲扭矩增加外翻稳定性的程度大于内翻稳定性。与文献的比较表明，在内翻负荷下防止关节外侧张开是随着扭矩增加（无论是伸展扭矩还是屈曲扭矩）内翻稳定性增加的原因。
