斜方肌反射：一個雙側動作調控的新反射

The Trapezius Reflex: A New Reflex for Bilateral Motor Control

顏威彰(Wei-Jang Yen) ； 褚自芳(Tzy-Fang Chu) ； 官大紳(Ta-Shen Kuan) ； 陳佳慧(Chia-Hui Chen) ； 洪章仁(Chang-Zern Hong)

《台灣復健醫學雜誌》 33卷2期 (2005/06) Pp. 79-85

https://doi.org/10.6315/2005.33(2)03

摘要

雙側斜方肌要緊密協調連結才能維持姿勢動作的穩定與平衡，但是一直缺乏解釋此種雙側調控(bilateral motor control)的直接神經生理證據，本實驗是第一個使用電學診斷的方法，證實雙側斜方肌於收縮動作上有密切的關連。本研究收集10位健康成年男性自願者的資料，我們發現電刺激單側副神經時，可使用肌電圖在同側的上斜方肌記錄到一個複合肌肉動作電位稱之為M型波（潛期平均為2.09±0.12 ms、振幅平均為11.56±3.79 mV及間期平均為33.64±2.47 ms)，同時在對側的上斜方肌記錄到一個反應較小的複合肌肉動作電位稱之為T型波（潛期平均為13.67±1.56 ms、振幅平均為346.50±169.59μV及間期平均為32.60±2.96 ms)，用sign test來分析左右兩側之間參數的差異，結果並無左右之間的區別（P值大於0.05），我們將此現象稱為「斜方肌反射(trapezius reflex)」。
我們所提出的斜方肌反射是一個簡單易行的電學檢查，可以作為評估斜方肌雙側調控功能的客觀工具，我們的實驗證明在一般正常人的身上，斜方肌反射皆可穩定的出現。斜方肌反射應該可以應用在中樞受損，或是副神經與斜方肌異常的診斷與評估之上，相信斜方肌反射將來在基礎及臨床上應該會有廣泛的應用。

關鍵字

雙側調控 ； 肌電圖 ； 斜方肌反射

並列摘要

Close links between the bilateral trapezii are essential for the stability and coordination of neck and shoulder movements. However, there is no direct neurophysiological evidence to support such a bilateral motor control mechanism. Our study is the first to use an electrodiagnostic method to prove the existence of this reflex. In this study, we have identified a new uniform or standardized technique, named the trapezius reflex (TR), which is able to evaluate proximal shoulder motor function. The TR is defined as an electrically elicited reflex that originates from the synchronized activation of both trapezii by electric stimulation of the accessory nerve on just one side.
To confirm the existence of TR, ten healthy male volunteers (all right-handed) with a mean age of 24.8±4.1 (19-31) years old were investigated. Electrical stimulation of the accessory nerve on one side should evoke a motor response, namely a compound muscle action potential (CMAP), on ipsilateral upper trapezius muscle called the M wave. In addition, another CMAP, named the T wave, should occur simultaneously and be picked up on the contralateral side. The accessory nerve was stimulated just above the midpoint of the posterior border of the sternocleidomastoid muscle. An active electrode was placed on the upper trapezius at the midpoint between the acromion and the spinous process of the seventh cervical vertebra together with a reference electrode on the acromion. The ground electrode was placed beside these two. The electrodes were arranged as a symmetric array on both sides of the shoulders. Bilateral CMAPs were simultaneously recorded using a two channel EMG apparatus. The sum of the electrophysiological data suggests there was no left-right difference in the bilateral M and T waves. Thus, we combined the data of the right and left sides to obtain values for the mean onset latency, amplitude and duration of the M wave as 2.09± 0.12 ms, 11.56±3.79 mV and 33.64±2.47 ms, respectively and the T wave as 13.67±1.56 ms, 346.50±169.59 μV and 32.60±2.96 ms, respectively. Consequently, the TR is a very stable motor response and is regularly obtained in healthy male volunteers.
The trapezius reflex is an easily applied electrodiagnostic technique and it could play an objective role in the electrophysiological diagnosis and assessment of bilateral trapezii control. The components of the TR should be able to provide a measure than can assess the functional integrity of central nerve system in terms of possible lesions, as well as detecting lesions within the peripheral accessory nerve and trapezius muscles. The importance of this study is that it presents the characteristics of the TR. Further work to correlate TR with possible clinical applications is obviously necessary, and is currently underway.

並列關鍵字

bilateral motor control ； electromyography ； trapezius reflex