Ranney D, Wells R
Department of Kinesiology, University of Waterloo, Ontario, Canada.
Anat Rec. 1988 Sep;222(1):110-4. doi: 10.1002/ar.1092220116.
The lumbrical muscle is clearly one of several possible extensors of the interphalangeal joints. With an origin on the flexor digitorum profundus tendon it is credited with unloading the elastic tension across the interphalangeal joints and thereby facilitating their extension. Its role at the metacarpophalangeal joint is not a matter of universal agreement. Attempts to simulate its action with weights over pulleys have not clarified this role, since true simulation would require the development of a means of applying force along the course of the lumbrical without pre-determining which end would move. Such a system is herein described; it uses a Bowden cable, which is commonly used to activate the brakes of a bicycle. After constructing length-tension curves of the profundus muscle in four fresh cadavers prior to the onset of rigor mortis, the interaction of realistic lumbrical loads with profundus elastic tension was studied. By contraction a lumbrical muscle adds a small but significant flexor force at the metacarpophalangeal joint, and thereby it is also capable of contributing to radial deviation and possibly rotation. As it runs from a flexor tendon to an extensor tendon and is endowed with a great many muscle spindles, the lumbrical could play a part in the control of finger movement by monitoring the rate of hand closing during grasp.
蚓状肌显然是指间关节几种可能的伸肌之一。它起于指深屈肌腱，被认为可减轻指间关节的弹性张力，从而促进其伸展。其在掌指关节的作用尚无定论。用滑轮上的重物模拟其动作并未阐明这一作用，因为真正的模拟需要开发一种沿蚓状肌行程施加力的方法，而不预先确定哪一端会移动。本文描述了这样一种系统；它使用一种常用于激活自行车刹车的鲍登缆线。在四具新鲜尸体出现尸僵之前构建了指深屈肌的长度 - 张力曲线后，研究了实际蚓状肌负荷与指深屈肌弹性张力的相互作用。通过收缩，蚓状肌在掌指关节处增加了一个小但显著的屈肌力量，因此它也能够导致桡侧偏斜并可能引起旋转。由于它从屈肌腱延伸到伸肌腱并拥有大量肌梭，蚓状肌可能通过在抓握过程中监测手闭合的速度来参与手指运动的控制。
