電気的記録法による上肢緊張反応の観察

抄録

An electrical recording method for arm tonus reaction (ATR) was devised, and analyses of the graphs of spontaneous and post-rotatory ATR's were conducted on 34 normal subjects and 54 vertigo patients. The patterns of spontaneous ATR's were categoried as normal (Type 1) or abnormal types (Types IIa, IIb, III).
Type I showed few differences in the height of the reaction between patients' left and right arms, and the normal limit of this difference was within 25mm. The abnormal types of spontaneous ATR showed a progressive downward curve of the diseased-side arm, and the so-called reversion phenomenon such as observed in the normal type curve was not detected.
Although only 25% of patients with vestibular lesions showed abnormal differences of more than 25mm, the incidence of abnormality rose to 52.5% when no-reversible curves of the spontaneous ATR were detected. Moreover, the incidence of abnormality rose even more highly when the curve of post-rotatory ATR was observed.
On the other hand, 75% of the cases with tumors of the posterior cranial fossa showed abnormal types of spontaneous ATR. This incidence of abnormality did not change even when observing the post-rotatorv ATR.
The result of observation using electromyograms (EMG) suggested that the appearance of spontaneous ATR was caused by hypotonus of the m. triceps brachii of the diseased side.
It was concluded from this investigation that ATR testing was valuable for diagnosis of the diseased side in patients with vertigo and that the electrical recording of ATR was useful in raising the detection rate of abnormalities in patients with peripheral vestibular disorders.