Rack P M, Ross H F
J Physiol. 1984 Jun;351:99-110. doi: 10.1113/jphysiol.1984.sp015235.
Human flexor pollicis longus tendons obtained at autopsy were subjected to repeated sinusoidal stretching movements. The associated force changes were almost in phase with the movement (force led position by less than 4 degrees), and alterations in the frequency of movement between 2 and 16 Hz had little effect on them. Examination of the thumbs of formalin-fixed cadavers demonstrated that the tendon exerts its force 7.4-8.0 mm in front of the axis of movement of the interphalangeal joint. From a knowledge of the tendon properties and the joint anatomy, one can calculate the changes in tendon length that would accompany any force change at the joint. Equipped with this information one can re-examine the responses to sinusoidal movements of the thumb interphalangeal joints of normal subjects. When the subject exerts a steady flexing force in which stretch reflexes play no important part, measurements of joint stiffness indicate that only a portion of the imposed movement reaches the muscle fibres. The extension of those (visco-elastic) muscle fibres lags behind the extension of the (elastic) tendon. Stretch reflexes contribute to the mechanical resistance of muscle fibres to low frequency (3-5 Hz) displacements, but in the presence of a compliant tendon the length of the muscle fibres does not determine the angle of the joint in any positive way. It is suggested that the compliant tendons of many thumb and finger muscles simplify the neuromuscular control of forces during gripping and handling movements.
对尸检时获取的人类拇长屈肌腱进行反复的正弦拉伸运动。相关的力变化几乎与运动同相（力超前位置小于4度），并且在2至16赫兹之间的运动频率变化对其影响很小。对福尔马林固定尸体的拇指检查表明，肌腱在指间关节运动轴前方7.4 - 8.0毫米处施加力。根据肌腱特性和关节解剖知识，可以计算出关节处任何力变化所伴随的肌腱长度变化。有了这些信息，就可以重新审视正常受试者拇指指间关节对正弦运动的反应。当受试者施加稳定的屈曲力且牵张反射不起重要作用时，关节刚度测量表明，施加的运动中只有一部分能传递到肌肉纤维。那些（粘弹性）肌肉纤维的伸展滞后于（弹性）肌腱的伸展。牵张反射有助于肌肉纤维对低频（3 - 5赫兹）位移产生机械阻力，但在存在顺应性肌腱的情况下，肌肉纤维的长度并不能以任何积极方式决定关节角度。有人提出，许多拇指和手指肌肉的顺应性肌腱简化了抓握和操作运动过程中力的神经肌肉控制。
