But slight allusion need be made to the symptomatology of neuralgia minor—the conditions are more or less familiar to every one. The pain, though usually most intense in that particular branch of the nerve which is most intimately related to the source of the neuralgia, is often referred to other branches of the same nerve-trunk, and sometimes to an entirely different nerve. Thus, in the case of an epithelioma of the tongue, the pain, though perhaps most acute in the region supplied by the lingual nerve, is nevertheless frequently referred to the ear along the course and distribution of the chorda tympani.
The pain is more or less continuous, often associated with exacerbations, but seldom paroxysmal. The patient frequently complains of heat and tenderness over the areas supplied by the nerve in question and, in almost every instance, there are points of special tenderness corresponding as a rule to the emergence of the nerve-trunk through some osseous foramen. Again, some relief may be obtained by the application of pressure over the site of that foramen. For example, neuralgia dependent on antral empyema is most acute in the region of the infra-orbital foramen, and relief may be experienced by pressure applied over that foramen.
In the event of failure to discover an exciting cause, some difficulty may be experienced in coming to a correct conclusion as to whether the case belongs to the minor types of neuralgia, or should be relegated to the more serious group of neuralgia major (tic doloreux). In general, however, the neuralgias minor may be distinguished from the major variety by the following features:—
(1) The presence of some detectable forms of nerve-irritation. In the neuralgias major there may be no such cause.
(2) The relief of symptoms on the successful treatment of the cause.
(3) The relative absence of those paroxysmal attacks which are so typical of neuralgia major.
(4) The infrequence of severe vaso-motor, trophic, and sensory changes in the regions supplied by the nerve affected. Such changes are more or less constant in neuralgia major.
(5) The wide distribution of the pain and its reference to other nerves, with no clear line of demarcation from neighbouring areas supplied by totally different nerves. In neuralgia major the pain, though often involving both second and third divisions of the fifth nerve, is referred to the areas supplied by those nerves only, with a clear line of demarcation from neighbouring regions.
In cases of neuralgia of doubtful origin one can only observe the effect of treatment and be guided by the results obtained.