Hammond M C, Kraft G H, Fitts S S
Department of Rehabilitation Medicine, University of Washington, Seattle 98195.
Arch Phys Med Rehabil. 1988 Feb;69(2):106-10.
Motor unit control measured by timed recruitment and termination of intramuscular electromyographic (EMG) activity provides muscle-specific quantification of deficits of the arm in chronic hemiparesis. Latencies to recruitment and termination of EMG activity of flexor carpi radialis and extensor carpi radialis longus were recorded from nine stroke patients and five age- and sex-matched control subjects, in response to buzzer signals, during maximal isometric wrist flexion and extension. Both agonist and antagonist recruitment times were slower in paretic than in control forearms (p less than .01). Termination of EMG activity occurred earlier in paretic forearms, primarily because of inability to maintain a prolonged muscular contraction. The effects of the variable lengths of testing trials reinforced these conclusions. The paretic extensor carpi radialis longus showed the greatest impairment with a very long latency to contract, and frequent failure to maintain a contraction. This study presents a new method of quantifying a common clinical problem in rehabilitation medicine.
通过对肌内肌电图（EMG）活动进行定时募集和终止来测量运动单位控制，可为慢性偏瘫患者手臂的缺陷提供肌肉特异性量化指标。在最大等长腕关节屈伸过程中，记录了9名中风患者以及5名年龄和性别匹配的对照受试者对蜂鸣信号做出反应时桡侧腕屈肌和桡侧腕长伸肌EMG活动的募集和终止潜伏期。患侧前臂的主动肌和拮抗肌募集时间均比对照前臂慢（p<0.01）。EMG活动在患侧前臂更早终止，主要是因为无法维持长时间的肌肉收缩。不同测试时长的影响强化了这些结论。患侧桡侧腕长伸肌受损最严重，收缩潜伏期极长，且频繁无法维持收缩。本研究提出了一种量化康复医学中常见临床问题的新方法。
