THE HIGH HOPES raised in World War I that electrodiagnosis would afford positive means of evaluating the degree of injury and amount of recovery of injured peripheral nerves unfortunately were not realized. For the most part, the examination consisted in determining the response of faradic and galvanic currents. In a few instances, the chronaxia was studied; in an isolated case, discontinuities in strengthduration curves were observed. Among the French and German workers, changes in the galvanic tetanus ratio were found to be so valuable that they were included with the other changes of the reaction of degeneration.
Since World War I, no new or additional methods of stimulating nerve or the nerve-muscle complex have been discovered. However, there has been developed apparatus by means of which accurate measurement of the amperage and duration of currents which are passed through muscles may be made, and, in fact, predetermined; the wave form