A BASICAL STUDY ON EVOKED ELECTROMYOGRAM / 体力科学

ABSTRACT

EVOKED EMG which had been initiated by Hoff man and Magladery was applied with central nervous disorders in attempting to determine the level of lesions.<BR>Also there were not many reports on basical studies without clinical reports. The purpose of this study was attempting to research the variability in normal healthy individuals (aged 18 to 34yr., six men) on (1) relationship between stimulus intensity and amplitude, (2) thresholds, (3) amplitudes in repetitive stimulations and (4) H-wave recovery curve.<BR>All stimulating durations were lmsec. and each stimulating intervals were 3 sec. One of the subjects wes stimulated by two electrodes-needle (inside) and rod (surface) electrode-for getting a thorough going over the dependence on both methods at the beg-inning of this study. As this results, there was no significants once without the differences on stimulating intensity by skin impedance. Therefore, there was no doubtfulness using the surface electrode, and it was used for all this studies.<BR>Thresholds of H-wave were 36 to 68V on six subjects and the maximum H-wave amplitudes (1.2 to 2.3mV) were found at 55 to 100V.<BR>On the variaiton of H-wave amplitudes with repetitive stimulations (stimulating intensity 50 to 95V), average amplitudes were 1.18 to 2.33mV (S.D. ; 0.19 to 0.3mV) and the coefficient of variation was 11 to 16.<BR>Refractory periods on H-wave recovery curves were 60 to 90msec. and a few ones was shown the pattern like as the patient's with thyrotoxicosis and cerebellar tumor.<BR>Although H-wave recovery rates were constant over 300 msec. (65.01±10.14% on 300 msec., 66.20±10.21% on 400msec., 67.29-9.9% on 500msec. average ± S.D.), variation was twice on 150msec. (53.82±26.08%) like as many reports. So, there may be some factors on this period.