[New electromyographic test for orthopedic diagnosis. Part II]

This study deals with mathematical assessment of physiologic and pathologic EMG frequency distribution by means of ranging. Material consisted of 161 pathologic EMG (63 myogenic cases, 98 neurogenic cases). In physiologic EMG power density distribution shows the highest values between 50 and 100 Hz, the lowest between 200 and 250 Hz. From 0 to 50 Hz power density increases, from 100 to 250 Hz-decreases. In patients with muscular diseases of different etiology the EMG power density spectrum is markedly different. The highest values appear more frequently between 0 and 50 Hz, sometimes also between 100 and 150 Hz. The frequency distribution allows mainly for assessing intensity of EMG pathology; is less useful for determination of its type.