NEURALGIA. 317 



painful of diseases, and may wear the patient out by the loss of sleep 

 and restlessness induced by the pain. 



TREATMENT. We can never cause resolution of neuroma. The 

 only true and trustworthy remedy is removal by the knife. 



CHAPTER III. 



NEURALGIA. 



As we have thus far made use of the anatomical changes lying at 

 the root of the disease as grounds of distinction, it is inconsistent to 

 treat of neuralgia as a disease, and to class it with neuritis and neu- 

 roma. Neuralgia is a combination of symptoms, which does not de- 

 pend on constant anatomical changes. Since no anatomical changes 

 can be discovered in many cases of neuralgia, and since, in many cases, 

 where changes have occurred, they alone are not enough to explain 

 the neuralgia, we seem driven to the above-mentioned inconsistency, 

 and we shall be unable to escape it in other morbid processes of the 

 nervous system, which are not due to certain anatomical causes. 



ETIOLOGY. The sensation of pain depends on the conduction to 

 the brain of the excitement of a sensory nerve by an abnormal irrita- 

 tion. Those sensations of pain, also, that are called neuralgic, depend 

 on a propagation of this excitement to the brain. If neuralgic pains 

 be distinguished from others, it is because they are due to the excite- 

 ment of the sensory nerves by different irritations, or by the action of 

 irritants at different places, from those causing ordinary pain. If a 

 blow, heat, cold, or other cause acting on the termination of the nerves, 

 induce pain, or if this be due to inflammation or other structural change 

 of the skin, mucous membrane, or of the parenchyma of different or- 

 gans, we do not call it neuralgia. But if we can discover no irritation 

 of the peripheral termination of a nerve as the cause of the pain, or 

 if it be probable that the irritation has affected the trunk of the nerve, 

 the pain felt in the distribution of the nerve is called neuralgia. We 

 may mention neuralgia of the supra-orbital branch of the trigeminus 

 which is not unfrequently induced by malarial infection, as the type of 

 the form where the pain occurs in the distribution of a nerve, without 

 the perceptible action of an irritant on the nerve itself, or on its termi- 

 nations. As a type of the second form, where the pain in the parts 

 supplied by a nerve is unmistakably due to an irritation of the nerve- 

 trunk, we may mention the very temporary neuralgia induced by 

 bruising the ulnar nerve near the elbow, at the part known as " the 

 crazy-bone." It is most probable that, in those cases, also, where the 

 injurious influence acting on the nerve escapes observation (as in neu- 



