ELECTRODIAGNOSIS BY MEANS OF PROGRESSIVE CURRENTS OF LONG DURATION

Abstract

In his description of the reaction of degeneration, Erb¹ included as a part of the changes the increase in galvanic excitability. This was a subject of dispute between Vulpian and Erb and Biedermann and Erb. Erb stated that there was an invariable increase in galvanic excitability, beginning in the second week and lasting as long as two months. Roberts,² in experiments on rabbits in which the bare muscle was stimulated, found this to be a constant sign; "about three weeks after nerve section the increased response to the galvanic current... is indeed very striking." In his experience in clinical work the results obtained were less constant. Employing percutaneous bipolar stimulation, we have found that two weeks after section of the sciatic nerve in the cat the liminal amount of current is small, usually below 1 milliampere —at times of the order necessary to stimulate the normal muscle but