Neuralgia and the Diseases that Resemble it

The tendency of cervico-occipital neuralgias is to spread toward the lower portions of the face, as observed by Valleix; in this case they become, sometimes, undistinguishable from neuralgias of the third division of the trigeminus. In the early stages of the disease, if the physician had been lucky enough to witness them, the true place of the origin of the pain would have been easily recognizable; at a later date it sometimes needs great care, and a very strict interrogation of the patient, to discover the true history of the disease. Sometimes, even, a cervico-occipital neuralgia which spreads in this way causes great irritation and swelling of the submaxillary and cervical glands; and I have known a case of this kind mistaken for commencing glandular abscess. The pain and tension were so great in this case, and the constitutional disturbance was so considerable, that the presence of deep-seated pus was strongly suspected, and the propriety of an incision (which would have been a hazardous proceeding) was seriously canvassed.

Experience is too limited, to judge by what I have personally seen, and the recorded cases with which I am acquainted, to enable us to say anything with confidence of the conditions, as to age and general nutrition of the body, which specially favor the occurrence of cervico-occipital neuralgia. Apparently, however, there is much reason for thinking that the immediately exciting cause of it is most frequently external cold. I have known it produced several times in the same person, by sitting in a draught which blew strongly on the back of the neck. And I am inclined to think that it is seldom the first form of neuralgia which attacks a patient, but usually occurs in those who have previously suffered from neuralgic pains either of the trigeminus or of some other superficial nerve. I have known it once to occur in a person, thus predisposed to neuralgic affections, in consequence of reflex irritation from a carious tooth, as was proved by its cessation on the extraction of the latter, although there was no facial pain.

(c) Cervico-brachial Neuralgia.– This group includes all the neuralgias which occur in nerves originating from the brachial plexus, or from the posterior branches of the four lower cervical nerves. The most important characteristic of the neuralgias of the upper extremity is the frequency, indeed almost constancy, with which they invade, simultaneously or successively, several of the nerves which are derived from the lower cervical pairs. The neuralgic affections of the small posterior branches (distributed to the skin of the lower and back part of the neck) are comparatively of small importance. But the "solidarite," which Valleix so well remarked, between the various branches of the brachial plexus, causes the neuralgias of the shoulder, arm, forearm, and hand to be extremely troublesome and severe, owing to the numerous foci of pain which usually exist. Perhaps Valleix's description of these foci is somewhat over-fanciful and minute; but the following among them which he mentions I have repeatedly identified; (1) An axillary point, corresponding to the brachial plexus itself; (2) a scapular point, corresponding to the angle of the scapula. (It is difficult to identify the peccant nerve here; the one to which it apparently corresponds, and to which Valleix refers it, is the subscapular; but we are accustomed to think of this as a motor nerve. Still, it is certain that pressure on a painful point existing here will often cause acute pain in the nerves of the arm and forearm.); (3) A shoulder point, which corresponds to the emergence, through the deltoid muscle, of the cutaneous filets of the circumflex; (4) a median-cephalic point, at the bend of the elbow, where a branch of the musculo-cutaneous nerve lies immediately behind the median-cephalic vein; (5) an external humeral point, about three inches above the elbow, on the outer side, corresponding to the emergence of the cutaneous branches which the musculo-spiral nerve gives off as it lies in the groove of the humerus; (6) a superior ulnar point, corresponding to the course of the ulnar nerve between the olecranon and the epitrochlea; (7) an inferior ulnar point, where the ulnar nerve passes in front of the annular ligament of the wrist; (8) a radial point, marking the place where the radial nerve becomes superficial, at the lower and external aspect of the forearm. Besides these foci, there are sometimes, but more rarely, painful points developed by the side of the lower cervical vertebræ, corresponding to the posterior branches of the lower cervical pairs.

The most common seat of cervico-brachial neuralgia has been, in my experience, the ulnar nerve, the superior and inferior points above mentioned being the foci of greatest intensity; an axillary point has also been developed in one or two cases which I have seen. Rarely, however, does the neuralgia remain limited to the ulnar nerve; in the majority of cases it soon spreads to other nerves which emanate from the brachial plexus. A very common seat of neuralgia is also the shoulder, the affected nerves being the cutaneous branches of the circumflex. I am inclined to think, also, that affections of the musculo-spiral, and of the radial near the wrist, are rather common, and have found them very obstinate and difficult to deal with. One case has recently been under my care in which the foci of greatest intensity of the pain were an external humeral and a radial point; but besides these there was an exquisitely painful scapular point. In another case the pain commenced in an external humeral and a radial point, but subsequently the shoulder branches of the circumflex became involved. A most plentiful crop of herpes was an intercurrent phenomenon in this case, or rather, was plainly dependent on the same cause which produced the neuralgia.

Median cephalic neuralgia is an affection which used to be comparatively common in the days when phlebotomy was in fashion, the nerves being occasionally wounded in the operation. I have only seen it in connection with this cause, that is to say, as an independent affection. One such case has been under my care. But a slight degree of it is not uncommon, as a secondary symptom, in neuralgia affecting other nerves. The traumatic form is excessively obstinate and intractable.

In the neuralgias of the arm we begin to recognize the etiological characteristic which distinguishes most of the neuralgic affections of the limbs, namely, the frequency with which they are aggravated, and especially with which they are kept up and revived when apparently dying out, the muscular movements. In the case above referred to, of neuralgia of the subscapular, musculo-spiral (cutaneous branches), and radial, the act of playing on the piano for half an hour immediately revived the pains, in their fullest force, when convalescence had apparently been almost established.

There is a special cause of cervico-brachial neuralgias which is of more importance than, till quite lately, has ever been recognized, namely, reflex irritation from diseased teeth. The subject of these reflex affections from carious teeth has been specially brought forward by Mr. James Salter, in a very able and interesting paper in the "Guy's Hospital Reports" for 1867; and Mr. Salter informs me that he has been surprised by the number of cases of reflex affections, both paralytic and neuralgic, of the cervico-brachial nerves, produced by this kind of irritation, and that he agrees with me in thinking that a peculiar organization or disposition of the spinal centres of these nerves must be assumed in order to account for the fact.

The liability of particular nerves in the upper extremity to neuralgia from external injuries requires a few words. The nerve which is probably most exposed to this is the ulnar. Blows on what is vulgarly called the funny-bone are not uncommon exciting causes of neuralgia in predisposed persons, and cutting wounds of the ulnar a little above the wrist are rather frequent causes. The deltoid branches of the circumflex and the humeral cutaneous branches of the musculo-spiral are much exposed to bruises and to cutting wounds. So far as I know, it is only when a nerve trunk of some size has been wounded that neuralgia is a probable result. Wounds of the small nervous branches in the fingers, for instance, are very seldom followed by neuralgia. I have no statistics to guide me as to the effect of long-continued irritation applied to one of these small peripheral branches, but it is probable that that might be more capable of inducing neuralgia. As far as my own experience goes, however, it would appear that a more common result is convulsion of some kind, from reflex irritation of the cord.

(d) Dorso-intercostal Neuralgia.– This is one of the commonest varieties of neuralgia, and yet it is very likely to be confounded with other affections not neuralgic in their nature. The disorder with which it is especially liable to be confounded is myalgia, which will be fully described in another chapter, and which, when developed in the region of the body to which we are now referring, is commonly spoken of as pleurodynia, or lumbago (according as it affects the muscles of the back or of the side), or muscular rheumatism. It must be owned that the severer forms of this affection can scarcely be distinguished from true intercostal neuralgia by anything in the character or situation of the pains. It will be seen, hereafter, however, that myalgia has its own specific history, which is very characteristic; at present, it is sufficient to remember that it is often extremely like neuralgia when situated in the dorso-intercostal region.

Dorso-intercostal neuralgia is an affection of certain of the dorsal nerves. These nerves divide, immediately after their emergence from the intervertebral foramina, into an interior and a posterior branch. The latter sends filaments which pierce the muscles to be distributed to the skin of the back; the former, which are the intercostal nerves, follow the intercostal spaces. Immediately after their commencement they communicate with the corresponding ganglia of the sympathetic. Proceeding outward, they at first lie between two layers of intercostal muscles, and, after giving off branches to the latter, give off their large superficial branch. In the case of the seventh, eighth and ninth intercostal nerves, which are those most liable to intercostal neuralgia, the superficial branch is given off about midway between the spine and the sternum. The final point of division, at which superficial filets come off, in all the eight lower intercostal nerves, is nearer to the sternum; and is progressively nearer to the latter in each successive space downward. There are thus, as Valleix observes, three points of division: (1) At the intervertebral foramen; (2) midway in the intercostal space; (3) near to the sternum. And there are three sets of branches (reckoning the posterior division) which respectively make their way to the surface near to these points.

In one of its forms, intercostal neuralgia is one of the commonest of all neuralgic affections. I refer to the pain beneath the left mamma, which women with neuralgic tendencies so often experience, chiefly in consequence of over-suckling, but also from exhaustion caused by menorrhagia or leucorrhœa, and especially from the concurrence of one of the latter affections with excessive lactation. It is especially necessary, however, to guard against mistaking for this affection a mere myalgic state of the intercostal or pectoral muscles, which often arises in similar circumstances with the addition of excessive or too long continued exertions of these muscles. "Hysteric" tenderness also sometimes bears a considerable resemblance, superficially, to true intercostal neuralgia, in cases where the genuine disease does not exist.

A less common but very remarkable variety of intercostal neuralgia than that just mentioned, is the kind of pain which attends a good many cases of herpes zoster, or shingles. It is only of recent years that any essential connection between zoster and neuralgia has been suspected. The occurrence of neuralgia as a sequel to zoster had indeed been mentioned by Rayer, Recamier, and Piorry, but the essential nature of the connection between the two diseases was evidently not suspected by Lecadre, when, as late as 1855, he published his valuable essay on intercostal neuralgia. M. Notta was one of the first to present connected observations on the subject. But it was much more fully discussed in a paper published by M. Barensprung, in 1861. [Ann. der Charite-Krakenhauser zer Berlin, ix., 2, p. 40. Brit. and For. Med. Rev., January, 1862.] This author showed the absolute universality with which unilateral herpes, wherever developed, closely followed the course of some superficial sensory nerve, and gave reasons, which will be discussed hereafter, for supposing that the disease originates in the ganglia of the posterior roots, and that the irritation spreads thence to the posterior roots in the cord, causing reflex neuralgia. We shall have more to say on this matter. Meantime, it seems to be established, by multiplied researches, that, though unilateral herpes may and often does occur without neuralgia, and neuralgia without herpes, the concurrence of the two is due to a mere extension of the original disease, which is a nervous one.

In young persons, zoster is not attended with severe neuralgia, but a curious half-paretic condition of the skin, in which numbness is mixed with formication, or with a sensation as of boiling water under the skin, precedes the outbreak of the eruption by some hours, or by a day or two. Painless herpes is commonest in youth. I remember, for instance, that, in an attack of shingles which I suffered about the age of eleven, there was at no stage any acute pain; only, in the pre-eruptive period, for a short time, I had the curious sensations referred to above: and the same thing has occurred in all the patients below puberty that I have seen, if they complained at all. From the age of puberty to the end of life, the tendency of herpes to be complicated with neuralgia becomes progressively stronger. The course of events varies much in different cases, however. In adult and later life the symptoms usually commence with a more or less violent attack of neuralgic pain, which is succeeded, and generally, though not always, displaced by the herpetic eruption. The latter runs its course, and after its disappearance the neuralgia may return, or not. In old people it almost always does return, and often with distressing severity and pertinacity. Six weeks or two months is a very common period for it to last, and in some aged persons it has been known to fix itself permanently, and cease only with life. In these subjects a further complication sometimes occurs. The herpetic vesicles leave obstinate and painful ulcers behind them, which refuse to heal, and which worry the patient frightfully, the merest breath of air upon them sufficing to produce agonizing darts of neuralgic pain. I have known one patient, a woman over seventy years of age, absolutely killed by the exhaustion produced by protracted suffering of this kind.

The foci of pain in intercostal neuralgia are always found in one or more of the points, already enumerated, at which sensory nerves become superficial. In long-standing cases acutely tender points are developed in one or more of these situations; not unfrequently the most decided of these spots is where it gets overlooked, namely, opposite the intervertebral foramen. H. G., a young woman aged twenty-six, who applied to me at Westminster Hospital, had suffered for twelve months from an irregularly intermitting but very severe neuralgia at the level of the seventh intercostal space of the left side. The violence of the pain was sometimes excessive, and when the paroxysm lasted longer than usual it generally produced faintness and vomiting. This patient had no sign of tenderness anywhere in the anterior or lateral regions, though the pain seemed to gird round the left half of the chest as with an iron chain, but an exquisitely tender spot, as large as a shilling, was found close to the spine; pressure on this always induced a strong feeling of nausea.

As an illustration of the herpetic variety of dorso-intercostal neuralgia, running a severe but not protracted course, I may relate the case of a medical man whom I formerly attended. This gentleman was about thirty-two years of age, and a highly neurotic subject: inter alia, he had already suffered from a severe and protracted sciatica; and, very shortly before the herpetic attack, had been jaundiced from purely nervous causes. His nervous maladies were undoubtedly caused by over-brain-work. In this case the neuralgia developed itself during the latter half of the eruptive period, which was rather unusually lengthened. It occupied the seventh, eighth, and ninth intercostal spaces of the side affected with herpes, and was very violent and acute, so that the patient expressed himself as almost "cut in two" with it. The pain ceased even before the vesicles had perfectly healed; a rather unusual occurrence in my experience. I shall refer to this case hereafter, as an example of what I believe to be the effect of a particular method of treatment in lessening the tendency to after-neuralgia. The result of my experience is certainly this – that if a case of herpes in an adult, or still more in an aged person, be left to itself, the amount of after-neuralgia will very closely correspond with the severity of the eruptive symptoms.

There is a variety of intercostal neuralgia which is of more importance than the commoner kinds. Occurring mostly in persons who have passed the middle age, it possesses the characters of obstinacy and severity which belong to the neuralgias of the period of bodily decay. It is at first unattended with any special cardiac disturbance. By-and-by, however, it begins to attract more careful attention from the fact that the severer paroxysms extend into the nerves of the brachial plexus of the affected side, so that pain is felt down the arm. In the midst of a paroxysm of intercostal and brachial pain, it may happen that the patient is suddenly seized with an inexpressible and deadly feeling of cardiac oppression, and, in fact, the symptoms of angina pectoris, such as they will be described in a future chapter, become developed. A case of this kind is at present under my care at the Westminster Hospital. The patient is a man only fifty-six years of age, but whose extreme intemperance has produced an amount of general degeneration of his tissues such as is rarely seen except in the very aged; he has the most rigid radial arteries, and the largest arcus senilis, I think, that I ever saw. This man has long been subject to attacks of violent intercostal neuralgia, and a recent access assumed the type of unmistakable angina. It is very probable that his coronary arteries have now become involved in the degenerative process. In this case, before the development of any marked anginal symptoms, the paroxysmal pain, from being merely intercostal, had come to extend itself into the left shoulder and arm.

Intercostal neuralgia not unfrequently accompanies, and is sometimes a valuable indication of, phthisis. I do not mean to say that the vague pains in the chest-walls, which are so very common in phthisis, are to be indiscriminately accounted neuralgia; on the contrary, they are, in the large majority of instances, merely myalgic, and arise from the participation of the pectorals, or intercostals, or both, in the mal-nutrition which prevails in the organism generally. But it happens, sometimes that a distinctly intermitting neuralgia occurs as an early symptom of phthisis; in fact, where there is a predisposition to neurotic affections, I believe that this is not very uncommon. The subjects are generally women; they are mostly of that class of phthisical patients who have a quick intelligence, fine soft hair, and a sanguine temperament. I have had one male patient under my care: this was a young gentleman aged eighteen, in whom a neuralgic access came on with so much severity, and caused so much constitutional disturbance, that the idea of pleurisy was strongly suggested. The paroxysms returned at irregular intervals for a considerable period: they were quite unlike myalgic pains, not only in their character, but more especially with respect to the circumstances which were found to provoke their recurrence. They were the first symptoms which lead to any careful examination of the chest; it was then found that there were prolonged expiration and slight dulness, at one apex. At this period, wasting had not seriously commenced; but, on the other hand, there was an extraordinary degree of debility for so early a stage of phthisis. I am inclined to think that self-abuse was the principal cause both of the phthisis and the neuralgia, acting doubtless on a predisposed organism, for his family was rather specially beset with tendencies to consumption. I may add here, that it has appeared to me that young persons with phthisical tendencies are specially liable to neuralgic affections as a consequence of self-abuse.

A special variety of intercostal neuralgia is that which attacks the female breast. The nerves of the mammæ are the anterior and middle cutaneous branches of the intercostals; and they are not unfrequently affected with neuralgia, which is sometimes very severe and intractable. Dr. Inman has very properly pointed out that a large number of the cases of so-called "hysterical breast" are really myalgic, and are directly traceable to the specific causes of myalgia; but there is no question in my mind that true neuralgia of the breast does occur, and indeed is frequent, relatively to the frequency of neuralgias generally. There are several kinds of circumstances under which it is apt to occur. In highly-neurotic patients it may come on with the first development of the breasts at puberty; and it may be added that this is especially apt to occur where puberty has been previously induced by the unfortunate and mischievous influences to which we had occasion to refer in speaking of certain other neuralgiæ. A neuralgia of the left breast occurred in a patient of mine, who attended the Westminster Hospital. She was only twelve years of age, and small of stature, but the mammæ were considerably developed. The face was haggard, there was an almost choreic fidgetiness about the child, and a very unprepossessing expression of countenance; the result of inquiries left no doubt that the patient was much addicted to self-abuse; and it seemed probable that to this was due the fact that menstruation had come on, and was actually menorrhagic in amount.

A very painful kind of mammary neuralgia is experienced by some women during pregnancy; but more commonly the mammary pains felt at this period are mere throbbings, not markedly intermittent in character, and plainly dependent on mechanical distention of the breast: such affections are not to be reckoned among true neuralgiæ. A true neuralgia of a very severe character is sometimes provoked by the irritation of cracked nipples. I have seen a delicate lady, of highly-neurotic temperament, and liable to facial neuralgia, most violently affected in this way. Vain attempts had been made for several consecutive days to suckle the infant from the chapped breast; when suddenly the most severe dorso-intercostal neuralgia set in. The attacks lasted only a few seconds each, but they recurred almost regularly every hour, and were attended with intense prostration, and sometimes with vomiting. Discontinuance of suckling was found necessary, for even the application of the child to the sound breast now sufficed to arouse a paroxysm of pain. Complete rest, protection of the breast from air and friction, and the hypodermic injection of morphia, rapidly relieved the sufferer.

(e) Dorso-lumbar Neuralgia.– The superficial branches of the spinal nerves emanating from the lumbar plexus are considerably less liable to be affected with severe and well-marked neuralgia than are the dorso-intercostal nerves. Pains in the abdominal walls, which are a good deal like neuralgia, are not uncommon; but the majority of them will be found, on careful observation, to be myalgia. At least, this has been the case in my own experience.

When true neuralgia of the superficial branches of the lumbo-abdominal nerves occurs, it develops itself in one or more of the following foci: (1) Vertebral points, corresponding to the posterior branches of the respective nerves; (2) an iliac point, about the middle of the crista ilii; (3) an abdominal point, in the hypogastric region; (4) an inguinal point, in the groin, near the issue of the spermatic cord, whence the pain radiates along the latter; (5) a scrotal or labial point, situated in the scrotum or in the labium majus.