Cooney W P, An K N, Daube J R, Askew L J
J Hand Surg Am. 1985 Mar;10(2):202-10. doi: 10.1016/s0363-5023(85)80106-4.
An electromyographic study of thumb muscles was performed on eight subjects by means of integrated polyelectromyography and simultaneous recordings of isometric flexion-extension, abduction-adduction, and prehensile pinch and grasp of the thumb. The integrated electromyographic signal proved to be an excellent index of thumb muscle activity, with a linear relationship found at low to middle levels of muscle strength. To facilitate understanding of thumb function, thumb muscles can be classified as primary or secondary on the basis of electrical potential activity. In isometric flexion, the flexor pollicis longus (FPL) was primary, whereas in extension, the extensor pollicis longus (EPL) and abductor pollicis longus were primary. In adduction, the adductor pollicis and EPL were primary and the FPL was secondary. In abduction, the abductor pollicis brevis and opponens pollicis were primary. The adductor pollicis, and FPL were nearly equal during pinch and grasp, with significant electrical activity increasing with greater force requirements. The first dorsal interosseous and EPL contributed secondarily in both pinch and grasp. When surgeons consider tendon transfers for nonfunctioning thumb muscles, the primary muscles should be replaced first to best restore pinch and grasp strength.
通过积分多通道肌电图以及同时记录拇指的等长屈伸、内收外展和对掌捏握动作，对8名受试者的拇指肌肉进行了肌电图研究。积分肌电信号被证明是拇指肌肉活动的一个极佳指标，在低至中等肌肉力量水平下发现其呈线性关系。为便于理解拇指功能，可根据电位活动将拇指肌肉分为主要肌肉或次要肌肉。在等长屈曲时，拇长屈肌（FPL）是主要肌肉，而在伸展时，拇长伸肌（EPL）和拇长展肌是主要肌肉。在内收时，拇收肌和EPL是主要肌肉，FPL是次要肌肉。在外展时，拇短展肌和对掌拇肌是主要肌肉。在捏握和抓握过程中，拇收肌和FPL几乎相等，随着力量需求的增加，显著的电活动也会增加。第一掌背侧骨间肌和EPL在捏握和抓握中起次要作用。当外科医生考虑对无功能的拇指肌肉进行肌腱转移时，应首先替换主要肌肉，以最佳恢复捏握和抓握力量。
