The term "myelitis" is too frequently loosely employed to designate cases of diffuse nonsystemic disease of the spinal cord in which the pathologic process bears no relation to infection but is due to toxins, avitaminosis, vascular disease, trauma, compression and similar causes. This naturally gives rise to great confusion in regard to the classification and diagnosis of these conditions. In order to clarify this subject we reviewed the clinical histories and studied histopathologically forty-three cases of nonsystemic disease of the spinal cord (excepting multiple sclerosis) in which the cases came to necropsy. The chief aim of this study was an attempt to establish definite pathologic criteria for the classification of these cases according to the pathologic observations and to correlate them with the clinical picture and the etiologic factor at the basis of each case.
As a result of this investigation we were enabled to classify our material as follows: