Abstract
Two types of multipolar electrode A and B, specially designed by the author were employed in order to investigate the spatial distribution of synchronous potentials of paretic muscles in poliomyelitis. Electromyograms were taken from the anterior tibial muscle of the patients mostly 3 years or more after the onset of the disease. With A type electrode consisting of 18 leads linearly located over a distance of 1.07mm in an injection needle, it was found that in paretic muscle synchronous potentials were detected in a larger area and their spike heights were larger than normal on the average. By using B type electrode which consists of 16, leads sparsely located over 14mm, it was found that synchronous potentials of relatively high amplitudes were apt to be detected from a larger area than normal. There was a considerable variety, however, in the patterns of distribution of synchronous action potentials and their spike heights from case to case. The possibilities of synchronization of the anterior horn cells, collateral sprouting of nerve fibers and ultra-terminal branching at the periphery were discussed on the basis of the present results.
