BY J. J. PUTNAM, M.D.
DEFINITION.—It is customary to describe as neuralgic those pains for which no adequate cause can be assigned in any irritation of the sensory nerves from outside, which recur paroxysmally, are unattended by fever, and are distributed along the course of one or more nerves or nerve-branches.
The general use of the term neuralgia further implies the common belief that there is a disease or neurosis, not covered by any other designation, of which these pains are the characteristic symptom. Of the pathological anatomy of such a disease, however, nothing is known; and if it could be shown for any given group of cases that the symptoms which they present could be explained by referring them to pathological conditions with which we are already familiar, these cases would no longer properly be classified under the head of neuralgia.
The attempt has frequently been made, and on good grounds, in obedience to this reasoning, to cut down the list of the neuralgias, strictly so called, and to account for many of the groups of symptoms usually classified under that head by referring them to anæmia or congestion of the sensory nerves, to neuritis, etc.
One of the best and most recent statements of this view is that of Hallopeau,1 who, although he does not wholly deny the existence of a neurosis which may manifest itself as neuralgia, goes so far as to maintain that the gradual onset and decline and more or less protracted course so common in the superficial neuralgias, such as sciatica, suggest rather the phases of an inflammatory process than the transitions of a functional neurotic outbreak, and that, in general terms, a number of distinct affections are often included under the name of neuralgia which are really of different origin, one from the other, and resemble each other only superficially. This subject will be discussed in the section on Pathology, and until then we shall, for convenience' sake, treat of the various neuralgic attacks as if they were modifications of one and the same disease.
1 Nouveau Dict. de Méd. et de Chir. pratiques, art. “Névalgies.”
GENERAL SYMPTOMATOLOGY.—The neuralgias may be conveniently divided into—1, external or superficial; 2, visceral; 3, migraine and the migrainoid headaches.
Superficial Neuralgia.
The most prominent symptom of a neuralgic attack of the superficial nerves is of course the pain, and sometimes, from first to last, no other sign of disease is present. In an acute attack the pain is usually ushered in by a sense of discomfort, which the patient vainly tries to shake off, or by a feeling of weight and pressure or of numbness and prickling, or of itching. Sometimes, though far less often than in the case of migraine, there are prodromal signs of a more general character, such as a feeling of thirst2 or of mental depression or drowsiness.