92 PRACTICAL ANATOMY. 



Two CASES OF REFLEX PAIN. 



A Patient has Pain in tJic Auditory Canal On examination you find no 

 local objective symptoms. Where may the real seat of the trouble be located ? 

 The auditory canal is supplied by the auriculo-temporal branch of the fifth 

 cranial nerve. The irritation may be sought for anywhere in the distribution of 

 this nerve, but, logically, those parts of the fifth nerve which experience has 

 proved are most liable to disease and injury should be interrogated first. We 

 may venture the assertion that the teeth, nose, eye, tongue, and antruin of High- 

 more represent about the order, in point of frequency. Here, then, is the 

 specialist invoked, since a carious tooth, an irritated gum, a septal spur, eye 

 strain, a lingual ulcer, or pus in the antrum of Highmore may be the immediate 

 exciting cause of the pain in the auditory canal. Conversely, a patient may have 

 a violent toothache, and examination may reveal neither exposed pulp nor irri- 

 tated gum. Conservative dentistry in this case would refer a patient to other 

 specialists, whose field of usefulness lies in the distribution of the fifth pair of 

 cranial nerves, primarily or secondarily, since reflex pain may be primary and 

 secondary. 



What is meant by primary and secondary reflex pain f 



The expression is a coinage, explained as follows : Where a carious tooth 

 manifests pain in the ear, eye, nose, anywhere in organs supplied by the same 

 nerve direct, this is called primary ; where, however, a carious tooth manifests 

 pain in distant regions, not supplied by the fifth nerve, but connected therewith 

 by communicating branches, this is called secondary. Let the following cases 

 illustrate the point and apologize for the coinage : 



1. A patient consulted a prominent dentist in this city for intractable pain in 

 a molar tooth. Examination revealed no objective symptoms of disease. The 

 patient was advised to consult other specialists in the primary radius of the fifth 

 pair of nerves viz., the eye, nose, ear, or throat man. The patient disregarded 

 the specific character of the advice, and consulted a specialist in the secondary 

 radius of the fifth nerve, the gynaecologist, who removed an ovarian tumor. The 

 pain in the molar did not return. 



2. Hilton reports a case from Romberg of cough and vomiting which ceased 

 only after a pruritus of the external auditory meatus was cured. The nerves 

 concerned in this case were the vagus and the trigeminus. 



The general practitioner of medicine who facetiously disclaims confidence in 

 reports of " toothache in the ear, and earache in an ovary," as he is wont to call 

 such cases, is placing himself on record with those who a few years ago hooted 

 at asepsis. Pain is a projectile, and specialists in medicine to-day are doing more 

 than any one else to harmonize physiological speculations and anatomical nerve- 

 distributions and nerve-communications, by furnishing clinical evidence of that line 

 of least resistance which pain, as a projectile, must follow. The student of prac- 

 tical anatomy is urged to give special attention to those parts of nerve-trunks 

 recorded in the text-books as communicating branches, for upon these depends 

 the rationale of reflexes, on which so much is said and written. 



The Glosso-pharyngeal Nerve (Fig. 54). You will find this nerve between 

 the jugular vein and internal carotid artery. It lies above the superior laryngeal 

 nerve, on the stylo-pharyngeus muscle and superior constrictor of the pharynx. 

 It is distributed to the back of the tongue and to the pharynx. This nerve is 

 deeply located. It can not be mistaken. It is the ninth cranial nerve. It 

 leaves the base of the cranium by the jugular foramen with the tenth and eleventh 

 nerves and the jugular vein. 



