Hj. Indergand et Bj. Morgan, EFFECT OF INTERFERENCE CURRENT ON FOREARM VASCULAR-RESISTANCE IN ASYMPTOMATIC HUMANS, Physical therapy, 75(4), 1995, pp. 306-312
Background and Purpose. Several case reports suggest that transcutaneo
us application of interference current (IC) produces physical blockade
of sympathetic vasoconstrictor fibers in peripheral nerves. To test t
his theory we studied the effects of IC on forearm vascular resistance
in asymptomatic humans. Subjects. One man and four women, aged 21 to
44 years ((X) over bar= 33, SD= 12), served as subjects. Methods. We m
easured forearm blood flow during IC applications over the left stella
te ganglion. Forearm vascular resistance was calculated by dividing me
an arterial pressure by forearm blood flow. Results. Interference curr
ent did not alter flow ((X) over bar= 5.6 [SD= 1.0] versus 6.2 [SD= 1.
1] mL/100 mL/min min) or resistance ((X) over bar= 15.4 [SD= 3.1] vers
us 13.8 [SD= 2.4] units). When sym pathetic outflow was augmented usin
g lower-body suction, IC again failed to alter flow or resistance. Con
clusion and Discussion. interference current applied over the stellate
ganglion does not alter forearm hemodynamics in asymptomatic individu
als. These findings challenge the concept that IC can block sympatheti
c vasoconstrictor impulses in peripheral, nerves. [Indergand HJ, Morga
n BJ. Effect of interference current on forearm vascular resistance in
asymptomatic humans. Phys Ther. 1995;75:306-312.]