本研究目的為利用可攜式牽張系統結合肌電訊號來追蹤觀察施打肉毒桿菌素後中風患者肘屈肌的痙攣情形。有十位慢性中風患者的主要肘屈肌，即肘二頭肌，接受肉毒桿菌素的治療。以修正版阿敘俄斯量表作為痙攣的臨床評估。在施打肉毒桿菌素之後，對病人進行追蹤評估；將在一定的活動範圍內（六十度）以不同的牽張頻率（1/3、1/2、1 和 3/2 赫茲）牽張肘關節，並同時記錄肘關節肌群的反應阻力及肌電訊號。於施打肉毒桿菌之前跟施打之後第二、第六和第九週，用速度相依之黏性元素（Bω）和黏性，以及反射肌電訊號閾值來作為評估痙攣程度的參數。我們可以發現修正版阿敘俄斯量表分數、黏性元素及黏性等參數在施打肉毒桿菌素之後均呈現下降；而在較高牽張頻率所量到的肌電訊號閾值則為增加（p<0.05）。從時間進程來看，我們結果顯示黏性元素以及黏性在施打肉毒桿菌素後六週內會隨時間慢慢下降，但是這個下降趨勢會在六週到九週時反轉。相似的結果也可發現在反射肌電訊號閾值上升趨勢反轉在施打肉毒桿菌素後超過六週。總結來說，我們可攜式痙攣評估系統可以用來做為臨床量測在施打肉毒桿菌素之後肌肉張力亢進下降的變化。黏性參數和反射肌電訊號閾值可用在臨床上來量化痙攣肌肉施打肉毒桿菌素後的張力變化。

　　The aim of this study is to utilize the portable stretching device combined with surface electromyography (EMG) for investigating the spasticity on the elbow flexors of stroke patients following BOTOX® injection. Ten chronic post-stroke spastic patients were injected BOTOX® in the main elbow flexor (i.e. biceps brachii). Spasticity was clinically evaluated with the Modified Ashworth Scale (MAS). The reactive resistance and reactive EMG of elbow joint induced at different stretching frequencies (1/3, 1/2, 1 and 3/2 Hz) through a 60 degrees range of motion were recorded following BOTOX® treatment. The velocity-dependent viscous component (Bω) and the viscosity (B) as well as the the reflex EMG threshold were used for evaluating the severity of spasticity at pre-injection as well as 2, 6, and 9 weeks after injection. In addition to decrease in clinical MAS scale, the viscous components and the viscosity of spastic elbow flexors were decreased and the EMG thresholds during higher stretching frequencies were increased after BOTOX® intervention (p<0.05). From the time-course changes, our results indicated that viscous components and viscosity slowly decrease with time around 6 weeks after BOTOX® injection in the most subjects but this decreasing trend is reversed from 6 weeks to 9 weeks after injection. Similarly results can be found in the reflex EMG thresholds which reversed the increasing trend at over 6 weeks after this treatment. In conclusion, our portable spasticity assessment device has been used for clinical evaluation of BOTOX® injection in reducing the muscle hypertonia. The viscous parameters as well as reflex EMG threshold can be used for clinical quantification of the changes in muscle tone after the BOTOX® injection of the spastic muscle.

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