Therapy 



Pradieal 



High Frequency Apparatus 



THE production of a highly concen- 

 trated heat in certain areas of the 

 body is desirable at times in the practice 

 of electro-therapeutics, and to make pos- 

 sible this localized application a special 

 form of current is supplied by the mod- 

 ern apparatus. 



THE THERM O-FARADIC CURRENT 



The thermo-faradic current is in ef- 

 fect a true D'Arsonval current of com- 

 paratively low potential but very high 

 frequency and comparatively large vol- 

 ume. The name thermo-faradic is sug- 

 gested by the pronounced thermal effects 

 together with a slight sensation of mus- 

 cular contraction, particularly when the 

 frequency is lowered slightly by an ad- 

 justment of the frequency regulator on 

 the coil. So effective is the current in 

 the production of local heat that the 

 hands grasping the electrodes may be- 

 come covered with perspiration and the 

 wrists acquire a sensation of warmth, 

 which increases to a degree where it 

 may become unpleasant if treatment is 

 prolonged. Incidentally, an interesting 

 experiment that illustrates the heating 

 effects in a graphic manner may be per- 

 formed by placing a piece of metal on 

 either side of a beefsteak and connecting 

 the thermo-faradic terminals to the 

 metal plates. The application of the cur- 

 rent full force will shortly serve to actu- 

 ally cook the steak. Notwithstanding 

 this evidence of the potential possibilities 

 of this form of current, it is probably 

 the safest of all the high-frequency 

 modalities to apply. The danger of shock 



* This article is the sixth of a series on high fre- 

 quency apparatus. The first article appeared in the 

 March issue of Modern Mechanics. 



is quite absent, and the discomfort of the 

 patient would soon manifest itself if the 

 heat were to become too great. This 

 symptom would be merely an indication 

 that the electrodes should be moved or 

 the current reduced. 



The thermo-faradic current is best ap- 

 plied through the agency of large metallic 

 electrodes which may either be placed 

 in direct contact with the area to be 

 treated, or, what is perhaps better, the 

 electrodes may be wrapped with ban- 

 dage and padded with cotton in order 

 that the application may be made 

 through a saline solution with which the 

 bandage is saturated. Another approved 

 method is to apply sheets of heavy tin- 

 foil to the desired area, bending the metal 

 so that it may conform with the shape of 

 the part under treatment. The movable 

 moist electrodes are probably the better, 

 however, as their positions may be 

 changed at will when the heat becomes 

 too great in one spot. In the application 

 of the current the operator should use 

 great care to see that the electrodes are 

 in absolute contact with the patient at 

 all times when the current is passing; 

 the separation of the electrode from the 

 body for even a fraction of an inch would 

 give rise to a spark which would be 

 rather painful and startling to the pa- 

 tient, although beyond this it would have 

 no serious consequences whatever. If 

 the precaution is taken to see that the 

 contact is good when the current is 

 turned on and continued good until the 

 switch is opened, there will not be the 

 slightest cause for concern. 



The use of the thermo-faradic current 

 is particularly indicated in cases of 

 sprains and chronic arthritis. 



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