SYNONYMS.—Myalgia rheumatica or myopathia; Fr. Rheumatisme musculaire; Ger. Muskelrheumatismus.
DEFINITION.—The affections included under this term are certain painful disorders of fibro-muscular structures. They are commonly found in persons the subjects of the rheumatic diathesis, and are characterized by pain and often spasm, and sometimes a slight degree of fever. No doubt as our knowledge increases so many attacks connected with painful states of muscles and fasciæ are eliminated from the somewhat uncertain group of muscular rheumatism. True inflammation is not believed to exist, and pathological investigation has rarely shown any morbid changes in the affected parts. The symptoms, therefore, have been attributed to some temporary hyperæmia, slight serous exudation, or neuralgic state of the sensory nerve-filaments. The strongest support is given to this statement from the absence of any marked tenderness in such affected muscles as can be sufficiently examined. In certain cases, undistinguishable clinically, it is quite probable that a periarthritis is in reality the principal factor in the case. In others, again, a subacute rheumatism affecting a joint seems to spread to the adjoining tendinous sheaths, and thus secondarily to attack the muscles themselves, the affection of which may ultimately remain the only condition present.
ETIOLOGY.—Muscular rheumatism is a very common affection. All ages are liable to its occurrence, but the part affected varies with the time of life, children and young adults being much more subject to torticollis, and older persons to lumbago and general rheumatism of the limbs. Amongst hospital patients the disease prevails more amongst men than women, owing doubtless to the greater exposure of the former to the cold; but amongst other classes the same difference is not seen. It is observed in all countries, but according to some writers it is unusually frequent in tropical climates, although there acute rheumatism is very uncommon. The causes of muscular rheumatism are mainly exposure to cold and strain or fatigue of muscles. If these two conditions coexist—e.g. standing in a draught of cold air or lying on the ground when fatigued—the chances of the affection coming are greatly enhanced. Strain, a twist of the body, or a false step can actively start an attack of this kind, and by the sufferers themselves it is constantly attributed to this cause. The part played by this element is difficult to determine, a very slight strain being often followed by great pain and distress from the subsequent rheumatic affection. Some individuals are specially prone to attacks, the slightest current of air, change of clothing, etc. being sufficient to determine its occurrence. These persons are often found to have suffered from rheumatism in some other form, and thus in them we must consider that the rheumatic diathesis furnishes the reason for their unusual susceptibility. It only remains to mention the fact that a disposition to gout seems to favor the development of muscular rheumatism. In gouty families, therefore, it has been observed to be common.
SYMPTOMS.—In all cases pain is the prominent, and in many cases the only, symptom present. In all except the more aggravated attacks pain is felt only when the affected part is disturbed. In such when complete rest or fixed immobility is maintained there is comfort, or at most a somewhat dull, uneasy sensation, but when any contraction of the muscles in question is produced, whether voluntary or otherwise, severe often excruciating pain is at once experienced, often giving rise to a sudden cry or causing the features to be contracted in a grimace. The suffering ceases almost at once when the muscular contraction is relaxed. In more aggravated attacks the pain is more severe, and besides persists, though to a less degree, even when there is no contraction. In rare cases when the maximum degree has been attained there is continuous pain, but the affected muscles are persistently maintained in a relaxed condition by means of true spasm in the surrounding muscles. Slow passive movement affects the subject of muscular rheumatism, and may often be accomplished with a little management without causing pain. If, at the same time, these muscles be handled by pinching and slight pressure, it will be found that they are very sensitive to the touch. When some tenderness does exist, it is slight and is not located in the district of the lower nerve-trunks. Pressure even sometimes allays pain. The constant effort to avoid pain gives rise to a feeling and appearance of stiffness, and thus characteristic attitudes and positions of the head, trunk, or limbs are voluntarily and persistently maintained. There is no spasm of the affected muscles; the distortion is the result of stiff contraction of the associated muscles, which thus forcibly fix the faulty one and hold it in a state of relaxation. Cramp or spasmodic contraction of a single muscle of a painful character does, however, sometimes occur in rheumatic subjects, and much resembles the condition above described. In the same persons also muscular rheumatism may occur in a much more fugitive or erratic form, frequently being nothing more than a slightly painful condition of some group of muscles which have in some way been exposed to cold. This may last but a short time, and either spontaneously disappear or be readily removed by exercise or friction. Muscular rheumatism is generally confined to one muscle or a single group of muscles. Those most liable to it are the very superficial and those easily exposed to cold (e.g. the deltoid and trapezius), powerful muscles often subjected to violent strain (e.g. the lumbar muscles), and those aiding in the formation of the parietes of the great cavities.
This affection very commonly exists without any constitutional disturbances, but sometimes there are present the symptoms of pyrexia—slight elevation of temperature and temporary disorder of the digestive organs—loss of appetite, constipation, and general malaise.
The acute forms generally last but a few days, terminating by gradual subsidence and final disappearance of the pain. The fugitive kind, already alluded to, may, however, be present more or less during several weeks.
DIAGNOSIS.—Errors of diagnosis between muscular rheumatism and a variety of other disorders are common. Laymen especially are only too apt to attribute pain felt in muscles at once to rheumatism of these muscles—a term which is badly abused. Some of these errors are of no great interest, but others are of the highest importance, for they may cause the onset of a serious disease to be overlooked. The principal affections to be borne in mind with reference to diagnosis are the following: organic diseases of the spinal cord (notably tabes dorsalis), causing peripheral pains as an early symptom; functional disorder of the same part, as hysteria or spinal irritation; intra-thoracic inflammation; the onset of an exanthem; the pains produced by the chronic poisoning of lead and mercury; neuralgia; painful spasm of muscle from deep-seated inflammation or suppuration. It is sufficient to indicate these various sources of fallacy, which, if remembered, can generally be guarded against by a consideration of the special features characteristic of each one.
TREATMENT.—The indications for the treatment are mainly two—viz. to relieve the pain and to counteract the diathetic condition generally present. The relief of the pain is accomplished in various ways, according to the seat of the trouble. In severe cases it is proper to resort to the hypodermic use of morphia, to which may be advantageously added some atropia. When the pain is seated in large muscles, the injection will produce better results if thrown not merely under the skin, but into the substance of the muscle. Sometimes perfect rest in bed is necessary to secure the required immobility; in other cases this can better be secured by plaster or firm bandages. Soothing anodynes are extremely useful locally, and counter-irritants also may be used with benefit. Liniments give us a convenient form of application. The best are those containing a considerable proportion of chloroform with either aconite or belladonna, or both. The repeated application of tincture of iodine often gives great relief. Galvanism sometimes proves a rapid cure. Continuous heat is nearly always grateful, and may be applied either in the dry form or by means of soft warm linseed poultices with or without a percentage of mustard. When these are discontinued, care should be taken to protect the affected muscles from cold by keeping them enveloped in flannel or woollen coverings.
Whilst these local measures are being adopted the constitutional disorder should also receive attention. A diaphoretic action should be set up. For this purpose the hot-air or Turkish bath at the outset would seem to be sometimes really abortive. Of medicinal means amongst the most reliable are liquor ammonii acetatis and Dover's powder. Pilocarpine occasionally proves useful. The fixed alkaline salts are also sometimes beneficial, such as the acetate and citrate of potassium and, at a later stage, the iodide of potassium. In a certain number of cases of muscular rheumatism the sodium salicylate acts promptly and well. This drug will succeed well in proportion as the evidence of the rheumatic constitution is well marked, as shown by the tendency on other occasions to attacks of acute articular rheumatism.
Persons who are subject to muscular rheumatism should be made to wear warm clothing, avoid draughts, guard against strains and twists, and in other respects to be careful of their general hygiene. Obstinately recurring cases will very often receive benefit from a visit to some of the natural springs known to possess antirheumatic qualities.
The chief varieties of muscular rheumatism, divided according to the locality affected, require some separate description.
1. Lumbago, or myalgia lumbalis, is that common form which attacks the lumbar muscles and the strong aponeurotic structures in connection with these. It is more frequently than any other form attributed to some effort of lifting or sudden twist of the trunk, but in many cases it owes its origin directly to exposure to cold. The pain comes on suddenly and renders the person helpless, the body, if he is able to go about, being held stiffly to prevent any movement or bending; if severe, he is absolutely compelled to observe complete rest in bed. The muscles, when handled, appear slightly sore, but no local point of acute tenderness can be found. This fact, with the characteristic shrinking from any movement, distinguishes lumbago from neuralgia and from abscess. Pain in the loins, more or less severe, is such a frequent accompaniment of disorder of several organs and parts that careful examination should always be instituted lest some serious organic disease with lumbar pain as a symptom be mistaken for a simple lumbago. The most important of these are perinephritis, lumbar abscess, spinal disease, abdominal abscess, and disease of the rectum and uterus.
2. Pleurodynia, myalgia pectoralis or intercostalis. Here the affected muscles are the intercostals, and in some cases the pectorals as well. Spasmodic pain is felt in one or other side of the chest, and is especially aggravated by the movements of respiration; it is rendered intense by the efforts of coughing or sneezing. Pleurodynia may be confounded with pleurisy, the distinguishing features being the absence of fever and the friction sound of pleurisy. Intercostal neuralgia is sometimes with difficulty known from pleurodynia, but in the former the pain is more circumscribed, more paroxysmal, and more easily aggravated by pressure than in pleurodynia, and when severe there are tender points in the course of the nerve a little outside of the middle line posteriorly (dorsal point) and anteriorly (sternal point). Now and then the hyperæsthetic areas become anæsthetic, and even patches of herpes may form in the course of the nerve, when doubt can no longer remain. From periostitis of a rib pleurodynia may be known by the fact that in the one the tenderness is marked in the intercostal space, and in the other in the rib itself. Pleurodynia is a frequent accompaniment of thoracic affections, causing cough, the frequent paroxysms of coughing tending to induce a painful state of the overworked muscles. The pain, which may be very great, can often be controlled by fixing the chest with imbricated plaster or a firm bandage. Dry cups sometimes answer very well; if more active measures are necessary, then hypodermic injections of morphia must be resorted to.
3. Torticollis, myalgia cervicalis, stiff neck or wry neck, caput obstipum. This term includes those cases of rheumatic idiopathic affection of one or more of the muscles of the side and nape of the neck, which fixes the head firmly in the median line or else in a twisted fashion, with the face turned toward the sound side. The disease can be recognized at a glance by the peculiar manner in which a person will turn his whole body round instead of rotating his head alone. It is much more common in children than in adults. The sterno-mastoid is the muscle chiefly affected, but any of the muscles of the neck may become rheumatic in the same way, and frequently several of them suffer at the same time. The most important point at the outset of an attack of wry neck is to determine whether we have to do with a true rheumatic (idiopathic) disorder, or whether the muscular stiffness is secondary to some spinal or vertebral lesion. The diagnosis is usually founded upon the suddenness of the onset, the absence of other symptoms of nerve disease, and the rapid course of the case, terminating in a cure in a few days. There is nothing special in the treatment of torticollis beyond what has been already said under the general heading.
Other forms of muscular rheumatism which have received special names and have been separately described are the following: myalgia scapularis or omalgia, when the surroundings of the shoulder are affected; myalgia cephalica or cephalodynia, an affection of the occipito-frontalis; and abdominal rheumatism, when the external muscles of the abdomen are involved.
SYNONYMS.—Nodosity of the joints (Haygarth); Chronic rheumatic arthritis, or rheumatic gout (Adams); Arthritis, rheumatismo superveniens (Musgrove); Goutte asthénique primitive; Arthritis pauperum; A. sicca; Usure des cartilages articulaires (Cruveilhier); Arthrite chronique (Lute); Progressive chronic articular rheumatism; General and partial chronic osteo-arthritis;216 Arthritis deformans.
216 Nomenclature of Diseases R. C. Physicians, London.
Neither my space nor time will permit of a history of this disease; it must suffice to say that Sydenham in 1766-69 appears to have first tersely described it and distinguished it from gout; that in 1800, Landré-Beauvais in his inaugural thesis made some observations upon the disease under the title of primary asthenic gout; that in 1804, Heberden, and more especially Haygarth, in 1805, pointed out some of the more striking clinical features of this disease, and distinguished it from both gout and chronic rheumatism under the title nodosity of the joints. The latter author, in the work mentioned, claims to have written a paper upon the subject twenty-six years previously, although it was not published; and to him belongs the merit of having so described the disease as to have given it a place in nosology. Incidental allusions were made to the affection in 1813 by Chomel, in 1818 by Brodie, and by Aston-Key in 1835; in 1833, Lobstein, and about the same time Cruveilhier, pointed out some of the more striking characters of the morbid anatomy of the affection. But it is to Adams of Dublin that we are indebted for the most complete account of the anatomy and of many of the clinical features of the disease—first in a paper read before the British Association in 1836, next in his article on "The Abnormal Conditions of the Elbow, Hand, Hip, etc.,"217 and finally in his able monogram "On Rheumatic Gout" in 1857. The contributions to this subject since that date have been very numerous as well as valuable from the leading countries of Europe, and I must not here attempt to assign to each investigator his proper portion of the work.
217 Todd's Cyclop. of Anat. and Phys. (1836-39).
It may be here remarked that Landré-Beauvais and Haygarth described more particularly that form of the disease which, beginning in the small joints of the extremities, tends to extend to the larger joints in a centripetal way, and to involve many of them—peculiarities which have given rise to the epithets progressive polyarticular chronic rheumatism, peripheral arthritis deformans, and which is the form of the disease usually described by physicians as rheumatic gout, rheumatoid arthritis, nodular rheumatism, and by the other names just mentioned. On the other hand, Key, Colles, Adams in his earlier paper, and R. W. Smith described the disease as it affects the larger joints, hip, shoulder, or knee, to one or two only of which it may be confined; and as this variety is frequently observed in elderly persons, and in them often involves the hip, it is often spoken of as senile arthritis, malum senile articulorum, morbus coxe senilis, mono-articular arthritis deformans, partial chronic rheumatism, and has been described by surgeons rather than by physicians. However, even when beginning in the hip or shoulder, the disease is apt to involve several of the intervertebral articulations, and not unfrequently to extend to other joints than the one first affected, and even to the peripheral joints. Its progressive and general nature is thus evidenced, whether it invade from the beginning a single large joint or several symmetrical small articulations. Finally, on this topic Charcot has insisted that Heberden's nodi digitorum contributes a special form of the disease under consideration, and proposes to call it Heberden's rheumatism or nodosities.218
218 Lectures on Senile Diseases, Syd. ed., 1881, p. 137.
Rheumatoid arthritis presents the clinical varieties or groupings of phenomena just mentioned, at times quite distinctly appreciable from one another, but sometimes more or less blended, yet even then manifesting in their periods of invasion and early stages an adhesion to all of these typical groupings. Charcot has especially dwelt upon these: 1st, the general or polyarticular and progressive form; 2d, the partial or oligo- or mono-articular form; 3d, Heberden's nodosities.
1st. The symptoms and clinical history of general or polyarticular and progressive rheumatoid arthritis. This is the most common form of so-called chronic rheumatic arthritis, the classical rheumatic gout, or rheumatisme noueux, and it may declare itself, as Garrod and Fuller pointed out, very rarely in an active or acute form, or, as it usually does, in a chronic and insidious form.
The acute form of rheumatoid arthritis closely resembles the milder varieties of acute articular rheumatism or the best marked examples of the subacute form of that disease. But it presents the following particulars, by which it may generally perhaps, but not always, be distinguished: while the temperature, the thirst, the furring of the tongue, the frequency of the pulse, the articular pains and tenderness, etc., are less developed than in acute articular rheumatism, there is wanting the profuse and continued perspiration, the early involvement of the endo- or pericardium in the inflammation, and the prompt prostration of the strength so commonly witnessed in that disease. On the other hand, while the rheumatoid affection may involve the larger joints—knees, ankles, elbows, and wrists—it almost certainly implicates the smaller joints of the fingers, and often of the toes. There is apt to be greater effusion into the synovial capsules (McLeod's capsular rheumatism) and into the synovial sheaths and bursæ about the affected joints than in ordinary acute or subacute rheumatism; further, the inflammation does not migrate from joint to joint, but obstinately persists in several of them, and more especially in the wrist and in the metacarpo-phalangeal joints of the index and middle finger, perhaps also in the ankles and in the metatarso-phalangeal articulation of the great toe. Instead of disappearing in four to six weeks, the articular inflammation continues, although the pain may abate very much, and the capsules of the joints continue swollen and rather tense. The muscles of the extremities waste, and are the seat of painful reflex spasms which interfere with the movements of the joints; and although the patient is capable of moving about, and is free from all febrile disturbance, one or several of his joints remain permanently swollen, painful, and crippled. Perfect restoration of all the affected joints seldom if ever occurs. In common with other observers, I have met with this acute form most frequently in young women twenty to thirty years of age—several times in connection with recent delivery or rapid child-bearing, or lactation; once after what was regarded by the medical attendant as an attack of acute rheumatism occurring not long after labor. It has been observed in children, and is not uncommon after forty. These patients usually suffer in their general health—become weak, pale, depressed in spirits, and lose flesh. In several cases of this form marked intervals of improvement have occurred; the local disease has ceased to progress, and tolerable comfort has been experienced, perhaps, till pregnancy, delivery, or lactation again determined a fresh outbreak of the disease. Sometimes, however, this acute form steadily advances, and in a year or two establishes changes in the cartilaginous and osseous structure of the affected joints. Such a case I met in a lady of twenty-one who had had a good deal of anxiety as a mathematical teacher, and whose illness set in during vacation while at the seaside. It proved obstinately progressive for several years, until several of the larger joints, as well as the smaller, were badly crippled.
The primary chronic form is much the more frequent, although between it and the acute variety there are many intermediate grades. For weeks or months the patient may experience numbness or formication and rheumatic pains in the limbs, perhaps with a sense of stiffness in the joints, especially felt after rest or the day after unusual fatigue. Then one or more joints—most frequently the metacarpo-phalangeal of the fingers—become painful, swollen, tender when touched, and inordinately hot; these symptoms may subside under rest or treatment, and after weeks or months recur, either without known cause or from exposure, fatigue, or some impairment of the health. Usually, the original joint is again affected, but frequently one or two more of the same on the other hand suffer likewise. More or less complete remissions of the pain and local inflammation now tend to take place from time to time and alternate with exacerbations or fresh attacks of the local disturbance, and the disease extends, as it were, centripetally and more or less symmetrically to the wrists, then to the elbows, and then to the shoulders, or from the toes to the ankles and thence to the knees—although there is no invariable sequence of this kind—and next to the hands; the knees are specially liable to invasion. Of Haygarth's 34 cases, in 2 the knees alone suffered, and "in all or nearly all the rest the hands, chiefly the fingers, were probably affected." In Charcot's 45 cases the début took place in the small joints of the hands and feet 29 times; in the hands, feet, and one large articulation, 7 times; in one large joint, and later in the fingers, 9 times. Even in this primary chronic form there is usually in the earlier stages some effusion into the joints; the soft parts of the articulation are thickened and swollen; obscure fluctuation in the smaller and very distinct fluctuation in the larger joints may be felt. The pain may be severe, especially at night, and during the exacerbations of the disease it varies greatly in its degree and persistency. The position and shape of the joints are altered, partly by spasmodic retraction of the muscles, and more or less by the effusion into the capsules and adjacent bursæ and sheaths, and the thickening of the soft parts covering the articulations. As the disease progresses further deformities ensue from the growth of new bone around the heads of the bones, the absorption of the articular cartilage, the development of masses of cartilage in the hypertrophied synovial processes and beneath the synovial membrane at the margin of the bones; the relaxation of the articular ligaments; and the displacements and subluxations of the unshapely bones composing the joint. The great wasting of the muscles of the member affected has some share in producing its unnatural appearance. In the advanced stage there is more or less abiding pain, soreness, and stiffness in the affected articulations, violent cramps are experienced in the course of the adjacent muscles, and pains either along the nerves or vaguely down the limbs. Crackings or creakings are to be heard, and grating is to be felt during the movements of the joints; these movements become more and more restricted, so that an immobility almost equal to that of true bony ankylosis is established, this result seldom occurring except amongst the carpal, tarsal, tibio-tarsal, and the vertebral articulations. Interlocking of the osteophites formed on and around the articular surfaces, and in other cases union of these surfaces by the interposition of newly-formed fibrous tissue, produce a spurious ankylosis destructive of the articular functions. In the very advanced stages the feet, ankles, and legs are often considerably enlarged and the integument thickened by a chronic oedematous infiltration, or the bones and soft parts are atrophied and the integument is pale, smooth, and attenuated, resembling parchment or the condition seen in certain stages of scleroderma and tightly drawn over the wasted rigid fingers. This primary chronic form is especially apt to progress steadily for many years, the joints earliest affected becoming gradually more distorted and crippled, and fresh joints becoming invaded until there may hardly remain a single sound articulation in the limbs, or even in the body; and at length the patient may be unable to feed himself or masticate or raise his chin from his sternum or rotate his head or stand.
The deformities of the several joints, being largely the result of muscular contraction, observe certain general types, which, however, are not peculiar to the disease, but occur in various affections of the nerve-centres, involving paralysis or spasm or both. Charcot has carefully described those met with in the hands, and I must refer to his masterly article upon chronic articular rheumatism for his account of them.
(1) It must suffice to say here that the predominant features of the hand in chronic rheumatoid arthritis are the following: The first phalanx of the fingers is either flexed upon the metacarpus or extended, and the terminal phalanx in like manner is either markedly flexed or extended upon the second, or these two phalanges are maintained in a straight line, while the first phalanx is, as usual, decidedly flexed upon the metacarpus.219 In all these varieties the hand is pronated; there is a great tendency to deviation of the fingers toward the ulnar border of the hand, although sometimes the deformed fingers stand out, not unlike a bunch of parsnips. The thumb escapes longer than the other fingers, and its metacarpo-phalangeal joint is usually flexed, rarely extended.
219 Lectures on Senile Diseases, Syd. ed., trans. 1881. Figs. 1 and 2, Pl. II., on the hand, give good illustrations of these deformities.
(2) The great toe, enlarged at the metacarpo-phalangeal articulation, is usually drawn to the outer border of the foot, across and above, but rarely below, the other toes, and the foot is usually abducted and flattened, the prominent internal border resting on the ground. The wrist, elbow, and knee-joints are generally flexed; the distal ends of the ulna and radius, more or less enlarged, project backward; the semi-flexed tibia is drawn backward on the femur and rotated outward, thus rendering the internal condyle of the femur prominent and displacing the patella toward the external condyle, and foreign bodies may frequently be felt in the enlarged knee- and elbow-joints. Finally, the extremities of the affected bones will, as a rule, be found enlarged and misshapen, and nodosities, rims, tips, ridges, and stalactiform growths of new bone may be felt on them.220
220 Figs. 12 to 18 and 22 in Adams's Treatise on Rheumatic Gout are nice illustrations of these deformities.
The general condition in this chronic form varies in different individuals, and there is no characteristic disturbance of the functions, such as obtains in chronic gout. There is no elevation of temperature, unless to a slight degree during an active crisis of the disease; the tongue may be clean, the pulse tranquil, the appetite and digestion satisfactory, and the urine normal or perhaps pale and of low density. Fuller, however, says that "more generally the complexion is sallow and the skin sluggish, and evidence of mischief is furnished by yellowishness of the conjunctivæ, constipation of the bowels, a pale and unhealthy character of the dejections, excessive flatulence after meals, turbidity of the urine, and fulness of the pulse." My own experience hardly harmonizes with this, and I have seen many persons suffering for years from the general and partial form in the enjoyment of excellent general health. Should, however, the disease develop in a person the subject of menorrhagia or other uterine disorder, or of repeated child-bearing, or after prolonged mental anxiety, some disturbance of the general health fairly referable to such disturbing conditions may be certainly looked for. In the advanced stages the prolonged suffering and confinement often induce anæmia, dyspepsia, and failing health.
More numerous and exhaustive analyses of the perspiration, urine, and blood in the disease are needed. There is no uniform condition of the skin; general perspirations, chiefly at night, often obtain, but I know of no authoritative report as to the chemical reaction of the sweat in this disease; Garrod221 and Charcot222 vouch for an absence of uric acid in the blood, while Marrot223 found both this acid and the urea below the normal quantity in the urine, although the acid increased notably under baths of high temperature.
221 Reynolds's Syst. Med., i. 918.
222 Loc. cit., p. 190.
223 Contribution à l'Étude des Rheum. Artic., Examen de l'Urine et du Sang, Paris, 1879, p. 42.
Certain affections other than the articular have been occasionally observed in persons suffering from rheumatoid arthritis, but many even of those authors who regard the disease as a form of rheumatism speak of these affections as coincidences, and not as essential manifestations of the disease. Charcot and Besnier, however, maintain the latter to be their true relation to the articular affection which they regard as chronic rheumatism. The two authors just named allege that all the visceral localizations that occur in acute articular rheumatism may obtain in the nodular form, but that such localizations are infinitely less frequent and serious than in the acute, subacute, or simple chronic forms of articular rheumatism—that endo- and pericarditis undoubtedly do occur in nodular rheumatism, and appear especially where there is an exacerbation of the disease and where there is some approach to the acute state.224 As Charcot has adduced these cardiac affections in proof of the rheumatic nature of rheumatoid arthritis, it is deserving of mention that he had personally met with but two instances of endocarditis and five of pericarditis, four of the latter having been discovered not during life, but in nine autopsies, and that he cites only eight other cases of endo- or pericarditis which had been either published or reported to him. He admits too that there had generally been in these cases, at some former period, an attack of acute rheumatism. Besnier, Homolle, Malherbe, Vidal, and Colombel, in their articles upon the disease under consideration, do not cite a single case in which they have seen cardiac disease in rheumatoid arthritis. On the other hand, McLeod, Garrod, Fuller, Flint, Senator, and Pye-Smith either deny or ignore the occurrence of cardiac disease as a manifestation or complication of this disease. My personal experience coincides with that of those authorities last cited, except in one instance, and that is open to the objection that the patient's father had had acute articular rheumatism, the mother was the subject of chronic deforming arthritis, and the patient had experienced during many winters an affection which began in the smaller joints and permanently damaged them; when first seen by me he had chronic disease of the aortic valves. He may have had true articular rheumatism as well as rheumatoid arthritis. His father had experienced the one, his mother the other. If those instances be excluded in which a former attack of acute rheumatism might be adduced in explanation of the supervention of cardiac disease, but few cases will remain to suggest that rheumatoid arthritis may develop endo- or pericarditis; and when it is borne in mind that in several ways the cardiac affections may have arisen as mere coincidences of the rheumatoid affection, it is well to wait for further evidence before accepting as proved the occurrence of cardiac affections as local manifestations of rheumatoid arthritis. Garrod's observation is still pertinent: "The form of the disease in which acute cardiac inflammation has occurred may be rather that of true articular rheumatism of a very subacute character."
224 Loc. cit., 172-175; Besnier, loc. cit., 699.
Nor is the evidence at all satisfactory in favor of any special tendency to the following affections, much less of their being local manifestations of rheumatoid arthritis: viz. pleuritis (McLeod, Fuller), asthma (Charcot), chronic laryngitis (Garrod), grave cerebral or spinal disturbances (McLeod, Fuller, Vidal), paralysis agitans, locomotor ataxia, sciatica, trifacial neuralgia, and albuminous nephritis.225
225 To mention only some of the many sources of cardiac disease other than rheumatism may be adduced scarlet and other fevers, extension of inflammation from the pleura or lung and other sources of local irritation, powerful or oft-repeated muscular efforts, Bright's disease, senile degeneration, etc.
Among the more frequent complications may be mentioned migraine, certain cutaneous affections, more especially psoriasis, prurigo, lichen, and some diseases of the eye, chiefly iritis, which is apt to be relapsing, and sometimes episcleritis. It is remarkable that iritis very seldom occurs as a complication of acute articular rheumatism.
The so-called rheumatic nodules occur also in chronic rheumatoid arthritis. It is not yet established that they are peculiar to rheumatism and to rheumatoid arthritis. Dr. Stephen Mackenzie has seen them in one instance in tertiary syphilis, the patient not having had arthritis, rheumatism, or chorea.
2d. The partial or oligo-articular form of rheumatoid arthritis, like the general or polyarticular variety, is usually a primarily chronic affection, insidious in its invasion and slow in its progress. It is chiefly observed in old persons, especially men (senile arthritis), affects frequently a single joint, and chiefly the hip, but occasionally the knee, shoulder, or spinal column, either as a consequence of special injury or of the wear and tear of life, or exposure to cold and wet, or even of what seemed to be simple acute or subacute articular rheumatism or gonorrhoeal rheumatism. When not the result of injury, two or three joints may suffer, both hips or knees, or hip and some of the vertebræ, hip, knee, and ankle of the same limb, and so on. Even in those cases in which the disease for a long time is confined to a single joint and may have been caused by an injury,226 other joints, finally, are apt to become affected, often in a symmetrical order. So that it may seem almost general, or at least polyarticular, just as the converse sometimes happens in the general rheumatoid arthritis of long standing, where the disease becomes greatly aggravated in one articulation and produces great deformity and destruction of it, the others remaining as they were.
226 See Ord's case, II., Brit. Med. Journal, i., 1880, 158.
The symptoms of this partial chronic form are very much those of the general form already described, but there is usually in the early stages less heat, tenderness, and swelling of the affected joint; the pain is less acute, but more abiding, and, with the exception of more or less stiffness or impeded movement in the joint, it may be the only sign of disease present, so that at this stage of the affection it may be taken for simple chronic articular rheumatism. But the disease persists; the voluntary movements become more painful and difficult; slight exercise of the joint is followed promptly by fatigue and aggravation of the pain, and yet the articular surfaces may be pressed together, and flexion and extension be practised, without causing much suffering. Slowly and continuously alterations take place in the affected articulation; with but little heat or redness it enlarges steadily, the soft parts becoming infiltrated and thickened, or effusion taking place into the capsule; the articular surfaces become irregularly depressed by the growth of osteo-cartilaginous rings, osseous nodosities, and stalactiform processes upon them, and these irregularities, together with one or several loose bodies, may be felt in the joint. The enlargement of the articulation becomes more apparent, owing to the wasting of the muscles of the limb; its movements become more and more restricted and difficult, although perhaps not more painful, and are attended with creakings and gratings perceptible to the ear and hand; and at last nearly all movement of the joint may be prevented by the alterations in the shape of the epiphyses, or by the interlocking of the osseous outgrowths, or in rare cases by actual union of the bones. This form constitutes, par excellence, arthritis deformans. In many instances there is little effusion throughout the process, notwithstanding the grave deformity in progress; hence the term dry arthritis. Even the partial form is sometimes more active in its invasion, as when it very rarely succeeds acute or subacute articular or gonorrhoeal rheumatism, or, more frequently, follows an injury.
The duration of the partial form is usually very protracted; it may be ten or twenty years. Exacerbations of the disease occur from time to time, in the intervals of which the patient may be free from pain, although the affected joints are seriously crippled.
The affection is not in itself fatal; the patient may attain an advanced age and die of some intercurrent disease, such as dysentery, pneumonia, cerebral hemorrhage, or other affection incident to old age.
A description of the features presented by partial rheumatoid arthritis affecting the hip (morbus coxa senilis), the shoulder, and other joints rather appertains to works on surgery, and only a glance at the evidences of the disease in the vertebral column (spondylitis deformans) will here be given. When the cervical vertebræ are implicated the power of rotating the head from side to side is usually preserved and is attended with a crackling noise, while the rest of the cervical region is stiff and the head cannot be bent forward; when the dorsal or lumbar vertebræ suffer the back becomes bent, the patient stoops greatly and cannot stand erect, and his body is shortened and more or less twisted. A careful examination will discover not only the great rigidity of the spine, and as it were fusion en masse of its joints, but in these persons the bony outgrowths may be felt. Occasionally the alteration in the vertebræ by compressing the cord or its membranes, or the spinal nerves and ganglia, may produce neuralgic pains in the cervical, dorsal, lumbar, or sciatic nerves, wasting of the muscles, more or less paralysis, and even vasomotor disturbances.
3d. Heberden's nodosities are certainly sometimes the effect of rheumatoid arthritis, implicating chiefly, often solely, the distal joints of the fingers, where it slowly forms two little hard nodules about the size of dried peas upon the side of the articulations. These are notably enlarged and their movements impaired, but pain is seldom experienced, and were it not for deviation of the end of the finger to one side or the knob-like excrescences upon the joints—appearances which much disfigure the hand—patients would not speak of the affection. In many cases these alterations likewise involve, but in a minimum degree, the first phalangeal articulations, and less frequently the metacarpo-phalangeal, and even some of the larger joints—the wrist, knee, or hip, etc. Like the other varieties of rheumatoid arthritis, this form occasionally has a more active invasion than is above mentioned, and may be attended by local pain, heat, and redness, or such symptoms may occur as exacerbations of the chronic disease.
Gout may precede these nodosities, or, as in the case of Charcot's,227 the latter may precede the former by several years. Finally, Charcot remarks that Heberden's nodosities are "often accompanied by asthma, migraine, neuralgia, especially of the sciatic nerve, and muscular rheumatism, and that these manifestations may alternate with the exacerbations of the disease."
227 Loc. cit., 198.
MORBID ANATOMY.—Every component tissue of the articulations exhibits signs of a chronic inflammatory process. In the chronic form affecting the larger joints the synovial membrane is found more or less congested, opaque, and thickened; at the point of its reflection upon the bones its fringes are thickened and injected and their villosities greatly increased in number, length, and thickness, and in extreme instances have been aptly compared to the wool on a sheep's back. The cartilage-cells normally existing in the synovial fringes likewise proliferate and develop into cartilaginous growths, many of which become infiltrated with lime salts, or even ossified, and in this way originate some of the foreign bodies, pedunculated or sessile, which are found in the joints. These may be attached to the synovial fringes, or imbedded in the membrane itself, or set free by rupture of their pedicles. In some examples these neoplasms resemble in size small melon-seeds; in others they form irregular masses, many of which are as large as hazel-nuts.
At the outset there is frequently an increase of synovial fluid, richer in mucine than natural, which lessens considerably in the later stages and becomes a turbid, viscid fluid of a dirty white or reddish-yellow color, containing no pus, but degenerating epithelium and fragments of villosities and cartilage. In many cases, more especially of the partial form, very little effusion into the articulations takes place (arthrite sèche).
The inflammatory irritation excites proliferating and degenerating processes in the cells and basis-substance of the cartilage covering the bones, and the changes described in connection with acute rheumatic arthritis ensue. Those parts of the cartilage covering the bones which suffer pressure in locomotion fibrillate on their surface, and either undergo mucous degeneration, resulting in ulceration and complete absorption, or are thinned and worn away by attrition. In either way the ends of the bones become laid bare. Those portions of the cartilage at the periphery of the joints which escape compression in the erect posture likewise proliferate, but, according to Cornil and Ranvier, in consequence of being covered by the synovial membrane the proliferating elements are retained in situ, instead of escaping into the articular cavity, and develop into actual cartilage, and may ultimately ossify. In this way irregular masses of cartilage (enchondromata) and bone (osteophytes) form around the heads of the bones, enlarging them considerably, altering their shape, encroaching upon the articular cavity as well as extending up the shafts of the bones, and displacing the capsules of the articulations. Similar productions of cartilage sometimes form in the thickened capsules and ligaments, especially in very protracted cases, or these parts become infiltrated with lime salts.
While these processes are going on at the periphery and the centre of the cartilages, in its deeper layers the proliferating cells are undergoing ossification and rendering the ends of the bones very dense and compact, so that under the attrition to which they are exposed by the articular movements they acquire the smoothness, polish, and white aspect of ivory (eburnated). It is probable that the articular ends of the bones participate in this proliferation and development of bone, which increases their compactness and is followed by eburnation. That the bone itself does sometimes play a part in the hyperostosis which is in progress is shown by an increase of an inch in the length of the right ramus of the maxilla over that of the left in Adams's first plate.228 Forster's229 and Ziegler's230 later investigations confirm this view. Nor is the periosteum exempted from the proliferating process which may have long existed in the several articular tissues, as is shown by the considerable enlargement of the diameter of the shaft of the long bones and by the osteophytes which form on the exterior of the vertebræ and often unite several of them together by a series of osseous splints, interfering with the mobility of the spine. Notwithstanding this development of cartilage and bone upon the exterior of the articular extremities, the interior, especially in old people or in very chronic examples of the general form of the disease, or rarely in the partial form, undergoes degeneration and atrophy. The spongy substance becomes rarefied, thinned, and friable (osteoporosis), so that it has been easily cut or crushed, and it is frequently loaded with fat. True ankylosis of the diseased joints is rare, except in the very small articulations when kept at rest; even under this condition fibrous ankylosis is not of frequent occurrence.
228 Illustrations of the Effects of Rheumatic Gout, London, 1857.
229 Forster, Handbuch der Path. Anat., p. 1000.
230 Virchow's Archiv, 1877.
Finally, the interarticular fibro-cartilages and ligaments and the long tendon of the biceps degenerate and are absorbed. The muscles in protracted cases suffer simple atrophy, but are sometimes the seat of an interstitial accumulation of fat. Thus far, no lesions of the nerves supplying the diseased joints nor of the spinal cord have been discovered.
ETIOLOGY.—The causation of rheumatoid arthritis is involved in much obscurity—in part, because sufficient attention has not been paid to its clinical varieties. We will examine first the general progressive form which is the more common.
In women it prevails during the child-bearing period. It is probably oftenest developed between twenty and thirty, and continues to occur frequently up to the period of the menopause, fifty, after which it develops comparatively seldom. Of Ord's 33 cases, 10 were between twenty and thirty years; 11 between thirty and forty; 9 between forty and fifty; and 3 between fifty and sixty.231 Children are not exempt. E. C. Seguin saw three children of the same family suffering from the disease at ages from two and a half to four years.232 Moncorvo233 met with an example at two years and a half, Laborde at four, and Charcot at ten. It occasionally begins in both sexes after sixty.
231 Brit. Med. Jour., 1880, 156.
232 The Med. Record, London, 1877, 797.
233 Du Rheumatisme Chronique Noueux des Enfans, Paris, 1880.
It is pre-eminently a disease of females up at least to fifty; after that it is not infrequent in men, and is then often only partial, at least at first. The most frequent progressive form, however, does often occur even in boys.
It is probably more frequently observed in cold and damp climates than in those of opposite qualities, for cold is regarded as its most common cause. However, it is met with in India and other hot climates. Besnier asserts it is almost unknown in the tropics, but new investigations are needed on this point.
Direct hereditary predisposition exercises but little influence, according to Garrod, and we certainly often see the disease confined to a single member of a large family, although Seguin saw three young children of one family affected with it, their parents being free from any disease. Trastour three times saw the children of women who were afflicted with nodular rheumatism already suffering from articular rheumatism; and Charcot once saw the grandmother, the mother, and the granddaughter successively attacked. At present I have a patient whose mother at fifty-five and maternal grandmother at sixty became subjects of a crippling polyarticular affection; another of my patients informed me that his mother and a young sister were like himself victims of the disease. This direct transmission appears to be rare, judging from my own experience and from the few instances of it mentioned by writers. But very many authorities maintain that simple acute and chronic rheumatism and gout in the parents predispose to rheumatoid arthritis in the offspring (Charcot, Trastour, Besnier). Now, the facts given in support of this opinion are not numerous. Trastour found that out of 45 cases of nodular rheumatism the father or mother were rheumatic in 10 instances, but the form of the rheumatic affection is not stated. Charcot, Besnier, and Homolle, although believers in the doctrine, do not cite an example in proof. However, in Pye-Smith's 27 cases of osteo-arthritis, five stated that rheumatism had occurred in their families. Thus, two fathers had had rheumatic fever, and one was rheumatic, and two sisters of different families had had rheumatic fever. Besides, the father of a sixth and the grandmother of a seventh had had gout.234
234 Guy's Hospital Reports, 3d Series, xix. 348.
The evidence in favor of the doctrine that true articular rheumatism transmits an hereditary tendency to rheumatoid arthritis does not appear to be conclusive, although it is highly thought of by those who regard the latter disease as a variety of rheumatism. Some considerations of an opposing character deserve mention. Acute articular rheumatism has very rarely passed continuously into rheumatoid arthritis, and very rarely has been followed at short interval by that disease; and in such exceptional cases the antecedent affection may have been really the acute form of rheumatoid arthritis, which closely resembles acute articular rheumatism. Trastour,235 Vidal,236 Charcot,237 and others admit that acute rheumatism can hardly be placed amongst the antecedents of the rheumatoid affection. Garrod238 with some others states that now and then acute rheumatism acts as an exciting cause of it, which appears to have been Fuller's view;239 he had repeatedly known it to commence apparently as a sequel of acute rheumatism. However, Ord met with a case in which the lesions of rheumatoid arthritis were present in a typical form in a patient who had mitral disease as a result of acute rheumatism, the arthritis having begun as a continuation of the acute attack.240
235 Thèse de Paris, 1853, p. 41.
236 Ibid., 1855, p. 9.
237 Leçons Cliniques, p. 214.
238 Reynolds's Syst. Med., 1870, i. 920.
239 Lib. cit., 333.
240 Brit. Med. Jour., 1880, i., 158.
That so common an affection as articular rheumatism should occur in the family or personal history of a patient the subject of the rheumatoid arthritis is not improbable; nasal catarrh and many other very common diseases must be frequent antecedents of the rheumatoid affection, yet are not causes of it. Much the same remarks apply to the view that gout in the parents may transmit a tendency to rheumatoid arthritis in the offspring. The experience of English physicians in this matter is hardly reliable, owing to the great prevalence of gout in England. In Canada and many parts of the United States, however, while gout is a rare disease, rheumatoid arthritis is a common one, and the writer has not found an intimate relationship to obtain between the two affections. It is not intended to deny that when the children of rheumatic or gouty parents fail in health owing to their inherited constitutional disease, they become liable to rheumatoid arthritis, for feeble health predisposes to that affection.
Finally, many of the difficulties connected with this subject are reasonably met by Hutchinson's241 doctrine that there exists a state of tissue-health which is transmissible by inheritance, which involves liability to inflammations of joints and fibrous structures, and upon this arthritic diathesis as a foundation may be built up, under the influence of special causes, a tendency to gout, rheumatism, or any one of their various modifications or combinations.
241 Trans. International Med. Congress, ii. 95; Guéneau de Mussy's chap., "De la Diathèse Arthritique," Clin. Méd., 1874, t. i. 317-338.
Hutchinson has demonstrated that gout is often followed by rheumatoid arthritis, the lesions characteristic of both affections coexisting in the same joint. Charcot and Cornil had previously observed the same thing.242 Acute and perhaps chronic rheumarthritis have sometimes preceded rheumatoid arthritis. If a predisposition, inherited or acquired, to rheumatoid arthritis exist, the occurrence of gouty or rheumatic irritation in the joints may suffice to induce the peculiar form of disturbance characteristic of the rheumatoid affection, just as injuries sometimes develop the partial form.
242 Mémoires de la Société de Biologie, 1864.
There is a group of conditions affecting the sexual functions and organs of women which appear to be specially connected with the general peripheral form of rheumatoid arthritis. The disease follows pregnancy, and specially frequent pregnancies, protracted lactation, and various disorders of menstruation. The latter influence obtained in ten out of eleven instances of the disease met with in girls under eighteen by Fuller.243 The frequency of the disease about the period of the menopause has been already mentioned. Todd noticed its coincidence with dysmenorrhoea. Ord in an able and original paper244 has lately dwelt upon ovario-uterine disorder or irritation as a frequent active cause of the disease, having in his opinion met with 33 instances of the kind. The relationship between these various conditions of the functions and organs of generation and rheumatoid arthritis cannot be regarded as settled. Garrod supposed that such conditions, by causing debility, predisposed to the articular disease. Todd, an ardent humoralist, held the nexus between the two to be unhealthy secretions of the uterus, leading to blood impurity; while Ord has ably defended Remak's view that a direct influence of the nervous system is the real link of relationship. It seems necessary to remark that mere coincidence may play a large rôle in the explanation of many of these cases. In 17 at least of Ord's 33 cases the conditions stated by that author cannot safely be adduced as anything more; and it is probable that they would be found present in much the same proportion in any other chronic painful disease of women.
243 Loc. cit., 335.
244 Brit. Med. Jour., i., 1880, 151-153.
Scrofula and phthisis are regarded by Charcot, Cornil, and Garrod as frequent antecedents of rheumatoid arthritis: the first had several times seen white swelling in youth, followed by nodular rheumatism in later life;245 and Fuller found that 23 out of 119 victims of rheumatic gout had lost a parent or one or more brothers and sisters by consumption.246 Chlorosis has several times preceded rheumatoid arthritis. When the prevalence of scrofula, phthisis, and chlorosis is borne in mind, it will not appear strange that they should frequently be found amongst the antecedents of rheumatoid arthritis, without inferring any other relationship between them. Gonorrhoeal rheumatism has also occasionally preceded rheumatoid arthritis, but Ord and Hutchinson are probably correct in regarding that affection as a variety of rheumatoid arthritis.247
245 Loc. cit., p. 208, foot-note.
246 Loc. cit., p. 334, foot-note.
247 Trans. International Med. Congress, vol. ii. p. 92; Brit. Med. Jour., 1881, p. 158.
Cold, especially when prolonged and associated with dampness, is commonly held to be the most common cause of general rheumatoid arthritis. A protracted residence in low, damp dwellings, deprived of the sun's rays and of a free circulation of air, is a condition thought most favorable to the provocation of this disease, perhaps years after the condition has been done away with.
Poverty and all that it implies are at least frequent antecedents of the disease (hence one of its epithets, arthritis pauperum), as are other debilitating influences, such as night-watching, insufficient food, mental worry, grief, anxiety, etc. Be it remembered, however, that the disease is frequently observed in the well-to-do, who live in dry climates and warm houses, are well fed, and want for nothing; so that the external conditions first mentioned are not essential causes of the disease, and many of them may act merely as adjuvants.
Direct injury of a joint from a blow, a fracture, a whitlow, etc. may sometimes induce a local rheumatoid arthritis, which may subsequently become multiple and involve several articulations more or less symmetrically.248
248 Vide Charcot's and Ord's cases, loc. cit.
The partial form presents some peculiarities of causation—thus: it occurs chiefly in advanced life (senile arthritis), much less frequently in middle life, very exceptionally in the very young. Men are much more liable to it than women. It is chiefly this variety which follows injuries, blows, dislocations, pressure, etc., and the disease may then be limited to the injured joint and be monoarticular, or it may extend and become polyarticular, or rarely, as in Ord's case, even general. This monoarticular form appears to be sometimes induced by other local irritations of the articular structures than those following traumatic influences; and as foreign growths in joints and gouty irritation may respectively induce the lesions indicative of rheumatoid arthritis, so, it is probable, may simple chronic rheumatism; and this may be the true relationship existing between these several affections. It is doubtful at present whether purely local irritation or injury of a joint can originate the alterations belonging to rheumatoid arthritis—that is, in the absence of all predisposition to that disease or of the arthritic diathesis. Cold and dampness are generally admitted to be causes of the partial form, but the evidence on this point is not altogether satisfactory. It may be that chronic articular rheumatism is induced by the prolonged operation of damp cold, and that the prolonged rheumatic irritation, aggravated by constant use of the joint and by occasional violence, ultimately superinduces the profounder alterations characteristic of arthritis deformans. It appears highly probable that if the predisposition exist, any long-abiding irritation of a joint, whether the result of violence or disease, may ultimately originate the alterations of the cartilages and bones which obtain in rheumatoid arthritis.
As regards the etiology of Heberden's nodosities, and their relation to other affections of the joints, the following summary must suffice: They obtain chiefly in advanced life, but do occur rarely in the young; they are probably somewhat more frequent in women than in men; although more frequently seen in the upper classes, the poor are not exempt from them, no doubt because they are specially exposed to slight but oft-recurring injuries of their digits, such traumatism being an exciting cause of the disease, especially when confined to a single joint. The affection is sometimes hereditary; both it and the general or the partial forms of rheumatoid arthritis may coexist in the same family and even in the same person. The alterations in the joints are identical with those found in the general variety of rheumatoid arthritis, and exist without deposits of urate of soda (Charcot). It resembles the general form of the disease just mentioned in its tendency to involve many symmetrical articulations at the same time, and the partial form in the rarity with which it extends beyond the joints first attacked. While Heberden's nodosities, as Haygarth taught, do occur independently of gout and the gouty habit, I believe with Begbie249 and Duckworth250 that in some persons they are evidences of gout or the gouty diathesis.
249 Contributions to Practical Med., 1802, p. 29.
250 "On Unequivocal Gouty Diseases," St. Bartholomew's Hospital Reports, vol. xvi., 1880, p. 190.
Quite recently a woman aged forty-eight consulted me with these nodosities beginning upon the last joint of the fingers, while she was the subject of vesico-renal irritation and was passing free uric acid in the urine. Hutchinson has twice seen them in combination with a peculiar insidious and painless inflammation of the iris and vitreous body, which occurs in the children of the gouty, yet such children have no deposits of lithates in their joints, nor any lithiasis, nor acute paroxysms of true gout, and he considers that "the last joint arthritis is to be regarded as in part gouty, and in part a kind of articular chilblain."251
251 Trans. International Med. Cong., ii. p. 96.
Lastly, in some instances they are no doubt the hybrid offspring of an inherited tendency to both gout and rheumatoid arthritis.
No more important principle in pathology exists than has been of late years insisted upon, especially by Jonathan Hutchinson and in his recent lecture by Sir James Paget252—to wit, that "by inherited dispositions, accumulating and combining or converging in definite proportions, new diseases may be developed and old ones be variously modified."
252 Lancet, ii., 1882, 1017-1021.
The pathogenesis of rheumatoid arthritis is the subject of differences of opinion very like those existing in regard to acute articular rheumatism. The weight of evidence is in favor of its diathetic relationship to rheumatism; and the doctrine of an arthritic diathesis and of the operation of the causes of the disease through the nervous system appears to be specially applicable to it, with less difficulty than to acute rheumatism, and the probability of a specific germ being its true cause is very remote. What seems to be necessary in addition to the preceding is, that the causes shall be more persisting and oft-recurring, so as to maintain a prolonged local irritation of the articular tissues, or that the neuro-arthritic diathesis shall be highly developed. Under these conditions the prolonged or oft-repeated application of cold and damp to the peripheral nerves, severe or oft-repeated slight injuries to joints, urethral or ovario-uterine irritation, chronic gout or rheumatism, or even, exceptionally, an attack of the acute form of these diseases, may originate rheumatoid arthritis; and all wearing influences, such as anæmia, excessive menstruation, prolonged lactation, innutrition, failing health, mental anxiety, or shock, etc., act as adjuvants in the development, aggravation, and maintenance of the articular disease.
DIAGNOSIS.—It is perhaps not possible to distinguish with certainty either the acute or the chronic form of rheumatoid arthritis from subacute or chronic rheumarthritis respectively before the characteristic deformities of the former affections have appeared. Acute rheumatoid arthritis, which is comparatively rare, may be said to exist, rather than subacute articular rheumatism, if the disease affect early and chiefly the smaller joints of the hands and feet alone or along with some of the larger articulations, especially the sterno-clavicular or the temporo-maxillary; if the effusion into the joints be abundant; if inflammation persist in the articulations first involved, notwithstanding the invasion of other joints; if the heart escape; if the patient be a female who is constitutionally delicate, or has borne children rapidly, or is the subject of disordered menstruation, or has been attacked soon after childbirth or during lactation;—finally, if, on cessation of the attack, one or more of the joints remain swollen and permanently enlarged and impaired in function. The coexistence of iritis, or a history of a previous attack of that disease not attributable to syphilis or gout, would strengthen the above view.