The BEST established feature of the neuropathology of poliomyelitis is the destruction of anterior horn cells of the spinal cord, this being generally recognized as the injury responsible for the enduring paralysis and atrophy of muscles of the trunk and extremities which may occur in this disease. Similarly, when present, paralysis of the cranial musculature or that of the oropharynx has been attributed to involvement of the analogous motor nuclei of the cranial nerves in the brain stem. As a consequence, and in spite of much evidence opposing such a view (Howe and Bodian1), there appears to be at least the popular impression that the only symptomatically important injury to the nervous system associated with poliomyelitis is the decrease in motor neuron collections.
This concept was recently challenged by Kabat and Knapp,2 who called attention to the frequent involvement of interneurons in the gray matter of the spinal