[Volume conduction in the electroneurographic study of arm and leg nerves]

Two arm and two leg nerves in each of a group of healthy subjects were stimulated electrically and the muscle action potentials were taken from the corresponding regions by surface electrodes. Volumetrically conducted potentials appeared in almost all cases, and other nerves were stimulated at the same time in many cases. The resultant errors in the calculation of the speed of pulse transmission are considerable. The use of a concentric needle electrode is recommended for recording evoked muscle action potentials.