Chapter II: The Peculiarities of Certain Accidental Acute and Chronic Diseases (7)

In the great mass of cases it is not strictly medical attention which is necessary, medical treatment, but mere ordinary care, precaution, and cleanliness on the part of the patient herself, so as to assist the efforts of nature: a week's rest in bed with healthy nutritious diet should be accorded every woman who has aborted, and this must be followed by at least one more week of quiet and confinement to the room, and not until a month after the accident has occurred should the patient resume her ordinary vocations.

I will not enter into the details of the after-treatment, as it is identical with that after labor at term. No decided treatment is called for unless demanded by symptoms peculiar to individual cases, yet ergot, quinine, and tonics are in place, and the same antiseptic precautions must be observed which are so highly appreciated in the lying-in room.

The patient must be kept in a recumbent position, the room quiet, and visitors excluded; a bed-pan must be used; the food must be easily digestible and nutritious; prepared tow or salicylated or borated cotton should be used in preference to the old-fashioned cloth to receive the discharge, and this must be changed with sufficient frequency: the parts must be washed with a lukewarm antiseptic wash, and vaginal injections of the same given as cleanliness demands, at least once a day; these should be hot (110°-120°) to further contraction. Corrosive sublimate 1:2000, carbolic acid 2:100, or boracic acid or borate of soda, serves a good purpose; intra-uterine injections are called for only in case of putrid or offensive discharge.

After the third or fourth day it is well to add an astringent, such as alum or tannin, to the hot vaginal douche, a teaspoonful to the quart, beginning with less, as some are very sensitive to these remedies, and increasing the strength if desirable.

{525} Iron and chinine are serviceable in aiding the system to regain its tone and in guarding against zymotic and malarial influences, to which it is more subject in this weakened condition. Ergot is here in its proper place: a three-grain pill of the aqueous extract should be given, at least during the first week, three times a day; I prefer this to the fluid extract in common use, which is nauseating to many. This drug, so much abused during progressing abortion and in labor before the contents of the uterus are expelled, answers an excellent purpose at this stage, and, together with the hot, astringent douche, may be relied upon to prevent subinvolution.

I can but repeat that the after-treatment should be that of the lying-in room after labor at term, modified according to circumstances, but never to be neglected, not even after the most simple cases. We must remember that it is indifference under these circumstances, under-estimation of the accident, which leads to years of suffering, by which subinvolution so insidiously destroys a vigorous constitution.

Rest, peace of mind, and quiet of body should, together with antiseptic precautions and tonic treatment, follow every abortion, intensified according to the severity of the accident. The two most important, and at the same time most neglected, features in the after-treatment of abortion, both of which are called for in even the most ordinary cases, are rest and cleanliness--rest, quiet of body and mind, to afford the proper conditions for the efforts of nature toward restitution and involution; cleanliness, antisepsis, to prevent external interference with this process and to guard the lacerated cavity of the womb, which offers so ready a receptacle for septic elements, against the dangers which threaten from without and so frequently bring about the rapidly-fatal termination of an apparently simple abortion.

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{527}

DISEASES OF THE MUSCULAR SYSTEM.

MYALGIA.

PROGRESSIVE MUSCULAR ATROPHY.

PSEUDO-HYPERTROPHIC PARALYSIS.

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{529}

MYALGIA.

BY JAMES C. WILSON, M.D.

DEFINITION.--An affection of the voluntary muscles, of which the chief, and often the only, symptom is pain on movement.

SYNONYMS.--Myalgia as a general term has few synonyms. It is sometimes called myodynia. This affection has no essential relation to rheumatism or the rheumatic diathesis; therefore the common use of the term muscular rheumatism as a synonym for myalgia is an error. This error has occasioned much confusion of thought and mistaken medication, and tends to maintain the obscurity which overhangs the subject of the so-called and often miscalled rheumatic affections in general. That true rheumatic processes may extend from serous or fibrous structures to contiguous muscular masses has, in the absence of demonstration, been assumed by many writers of authority, but that acute or subacute rheumatism, with its recognized characters, ever manifests itself primarily or exclusively as an inflammation of muscle-substance is an assumption wholly without clinical or pathological support.

The term myo-rheumatism is as inapplicable as muscular rheumatism, and lacks the sanction of usage. Myositis is a term used to describe (1) an acute inflammation of muscle, often traumatic, and commonly attended by suppuration, and (2) a chronic indurating inflammatory process, not infrequently due to syphilis. Neither of these conditions resembles the affection under consideration in its clinical aspects, nor is allied to it pathologically.

As manifested in particular muscles or groups of muscles myalgia has been described under the terms cephalodynia, torticollis (myalgia cervicalis), pleurodynia (m. pectoralis seu intercostalis), lumbago (m. lumbalis), dorsodynia, omodynia, scapulodynia (m. dorsalis), etc.

This affection must, in the present state of our knowledge, be classified with the diseases of nutrition in the more narrow sense. It is not a diathetic disease.

HISTORICAL CONSIDERATIONS.--To Inman[1] of Liverpool is due the credit of having first pointed out the frequency of this malady and the ease with which it may be mistaken for other and much more serious diseases--an error in diagnosis which has been followed by serious results, especially in the case of nervous and self-centred females and other hypochondriacal persons. It cannot, however, be denied that this author, carried away by his enthusiasm, exaggerated the importance of this local {530} affection at the expense of undervaluing the frequency and significance of other painful disorders which have their origin in the nervous system. To Inman we also owe the term myalgia, which has the positive merit of embodying the idea of pain as the chief symptom of the disorder and the muscles as its seat, and the not inferior negative merit of implying no erroneous theory as to its nature and cause.

[Footnote 1: Thomas Inman, M.D., _Certain Painful Muscular Affections_, 1856; _Spinal Irritation Explained_, 1858; _On Myalgia, its Nature, Causes, and Treatment_, 1860.]

This affection is described in few even among the recent textbooks; in others it receives merely incidental mention; in the majority of them it is passed over in silence. Yet it is obvious that the descriptions of muscular rheumatism, which are rarely omitted, are based upon and refer to cases of various kinds which for the most part are not rheumatic at all, and very frequently are examples of true myalgia.

ETIOLOGY.--(_A_) Predisposing Influences.--Myalgia is "essentially pain produced in a muscle which is obliged to work when its structure is imperfectly nourished or impaired by disease." Hence all influences which unfavorably affect the nutrition of the muscles, all diseases which directly affect the integrity of their structure, predispose them to this affection. The defect in nutrition may be only relative to the amount of work the muscle is called upon to do, or there may be absolute malnutrition, implicating the whole body. The muscle may be impaired by a local disease which affects it alone, or it may share in morbid processes which also involve other and distant structures.

Sedentary occupations, leading as they do to poor nutrition of the muscular system from want of proper use and exercise; malnutrition from a diet deficient in amount or defective in kind, or in childhood from too rapid growth; the chronic wasting diseases; the state of convalescence from acute maladies; and, finally, degenerative diseases of the muscles themselves,--all favor the development of myalgia. Among the acute diseases which by their derangement of nutritive processes especially render those who have suffered from them liable to this painful affection of the muscles during convalescence, is acute articular rheumatism or rheumatic fever. It is this fact, taken together with the use of a misnomer, that has given rise to the view that the muscles share with the serous and fibrous structures in the lesions of that disease, and that myalgia is rheumatism of the muscles.

There is, however, over and above these defects in nutrition, an especial predisposition or idiosyncrasy, the nature of which is unknown, which renders certain individuals far more liable to suffer myalgic pain than others. This predisposition is encountered in those who have an inherited or acquired gouty habit and in those who are free from gout with perhaps equal frequency. It is not associated with a special liability to true rheumatism.

(_B_) Exciting Causes.--Myalgia is a local affection, and depends for its causation upon a derangement of the balance between the nutrition of the affected muscles and the work they have been called upon to do. Hence the most common exciting cause is (_a_) overwork pure and simple, especially overwork which brings into excessive and prolonged exercise unaccustomed muscles. Next in frequency is (_b_) exposure to cold, and especially to damp cold, when overheated or overfatigued. Finally (_c_), inevitable and incessant contractions, such as are physiological and are performed without consciousness or sensation in a healthy state of the {531} muscles, will, in muscles that are defectively nourished or have undergone fatty, granular, or fibroid degeneration, cause more or less distinct myalgia.

As examples of myalgia due to the first of this group of causes (_a_) I may cite the pain in the adductors of the thighs after a hard ride when out of practice; the epigastric pain in children suffering from measles or other acute affection attended with persistent cough; and the pain of spasm, in particular that which follows tonic spasm, such as occurs from reflex causes in the calves of the legs at night and in bathers. Many of the pains of childhood, which are classed in common parlance together under the name of growing pains, are myalgic in their nature.

Examples of the second form (_b_) may be instanced in the pains of wry neck or lumbago, such as often occur in those who, being very tired, but otherwise healthy, fall asleep in a draught of air, or in those who, coming home at evening in cold weather, find a leaking pipe in the cellar, and stooping over to stop it, or in some other emergency of every-day life, bring into excessive use unaccustomed muscles in an atmosphere that is at once cold and damp.

Examples of the third group (_c_) are common enough in the flying or fixed muscular pains and soreness that occur in wasting chronic diseases and in the convalescence from acute maladies when prolonged muscular effort is too early undertaken. Certain forms of præcordial pain that occur in degenerative lesions of the muscular substance of the heart are without doubt myalgic in character, and will, when the clinical data of such conditions come to be more fully understood, be recognized as having more or less diagnostic value.

SYMPTOMATOLOGY.--The chief symptom, the one symptom that is common to all the cases, is pain. It is sometimes, especially in acute cases, constant; more frequently it is very slight or wholly absent when the patient is at rest, with the affected muscles in full extension, but it is invariably present or aggravated when the muscles are called into action. It is experienced throughout the muscular mass, but is most intense at or near the point of tendinous insertion. Its character is usually stabbing or stitch-like, but prolonged; sometimes it is acutely dragging or tearing; in others it is like the soreness felt on moving a contused or inflamed part. It is frequently in acute cases, almost always in chronic cases, accompanied by a sensation of stiffness in the affected muscles. The pain is essentially the same in all cases, variations in its character and severity being determined by the opportunities afforded the muscle for physiological rest. It is in accordance with this statement that the most obstinate, and the most severe form of myalgia is that which occurs in the intercostal muscles and their fibrous aponeuroses--pleurodynia. Here the affected muscles are constantly concerned in the movements of respiration, and have no time for physiological rest except in the intervals of those movements. Scarcely less stubborn and severe are the myalgias of the great muscular masses, of which the principal function is to maintain by their nicely-balanced and ever-varying contractions the erect position of the head and trunk. Less painful and of shorter duration are the myalgias of the limbs--less painful because prolonged intervals of absolute rest may be voluntarily secured; of shorter duration, because it is by rest that the balance of the nutrition is most speedily restored.

{532} There is usually some degree of tenderness over the whole extent of the myalgic area, becoming more marked in the regions of tendinous insertion, to which it is, however, in many cases restricted. It is elicited upon moderately firm pressure, and is not associated with cutaneous hyperæsthesia.

Spasm is absent in the acute cases, except when the muscles are brought into use. Its occurrence has much to do with the intensity of the suffering then caused: in chronic cases a condition of tonic spasm or spastic rigidity, with more or less persistent painfulness, comes on, and finally in very chronic cases such tissue-changes take place as result in great impairment or absolute loss of contractile power, with or without atrophy.

Objective signs are absent, except that it is evident that the patient assumes by preference an attitude of repose, and that he keeps the involved structures as much at rest as possible. Pyrexia does not occur; the appetite and digestion are not impaired; acid sweats are not present; the urine shows no constant or characteristic alteration; there is no tendency to endo- or pericardial inflammation. If constitutional disturbance be present, it is trifling and due to prolonged local suffering and want of sleep. In by far the greater number of instances the patient remains in his usual health except the local malady.

Myalgia may affect the voluntary, and perhaps also the involuntary, muscles of any part of the body. Those most frequently involved are those subjected to continuous and excessive work, and at the same time liable to exposure to cold and damp. Single muscles or groups may be affected. The most common and important varieties are--

(1) Cephalodynia, manifested as a superficial headache, increased by movement of the scalp and attended by tenderness on pressure.

(2) Torticollis; wry neck, stiff neck--a very common form, involving the muscles of the neck, especially the sterno-cleido-mastoid. The affection is usually limited to one side, toward which the occiput is more or less firmly rotated and flexed. Great pain is experienced in attempting to turn the head in the opposite direction. The position is extremely constrained and awkward; the head cannot be moved in any direction without moving the whole body, and every effort at motion is accompanied by pain which calls forth involuntary grimaces.

(3) Omodynia, Scapulodynia, Dorsodynia--forms in which the muscles of the shoulders and upper part of the back are affected. They are very common, especially among laboring men.

(4) Pleurodynia, Myalgia of the Chest-walls.--The intercostals, pectorals, and serratus magnus may be involved. The pain is frequently referred to the region of the interdigitations of the serratus magnus with the external oblique. It is very often seated in the infra-axillary region, and is much more common on the left side. It is usually very severe, and is increased by all movements that bring the affected muscles into play. The focus of pain is sometimes a very limited spot, which is exquisitely tender upon pressure. Sometimes the pain alters its position from time to time. It is increased by deep inspiratory efforts and such acts as sneezing and coughing. Extreme flexion of the trunk from side to side also aggravates the pain. Pleurodynia sometimes comes on in consequence of severe and protracted cough, as in patients suffering with phthisis. It is then apt to affect both sides.

{533} This form of myalgia simulates pleurisy, from which it is to be distinguished only by careful physical examination.

(5) Myalgia of the abdominal walls usually affects the recti muscles, and often assumes the guise of an acute, agonizing pain in the epigastric or pubic regions--occasionally so severe as to be mistaken for peritonitis. It is sometimes due to cough, especially in measles, but is more commonly met with in overworked and underfed tailors and cobblers as a result of the excessive action of the recti muscles in maintaining the bent posture assumed by such craftsmen at their toil.

(6) Lumbago, myalgia lumbalis.--The great muscular mass occupying the lumbar region is peculiarly prone to attacks of myalgia. Lumbago is very common in the middle and later periods of life. The attack is usually sudden and severe. Both sides are, as a rule, affected, but not to the same extent. There is constant pain across the loins, dull and aching, rarely absent altogether, always sharply aggravated by such movements as bring the affected muscles into play, and then becoming stabbing in character and almost unbearable in intensity. The spine is held stiffly, and the body is often bent slightly forward. Efforts to stand erect, to rise from the sitting posture, or to recover from the stooping position, such as is assumed in lacing one's shoes and the like, greatly aggravate the pain. In the more severe cases the patient cannot stir in his bed. There is usually tenderness upon pressure, and palpation often discovers a distinct sense of abnormal tension and resistance in the muscles.

(7) The aching, dragging pain in the back of the neck common in poorly-nourished, nervous women and in other cases of neurasthenia, the so-called pain of nervous exhaustion, is myalgia. It is felt chiefly during fatigue, is present in the erect posture, and is almost always relieved when the patient lies down. It is referred sometimes to the base of the skull, sometimes to the whole of the back of the neck, but more commonly to the spinal region just above the level of the upper borders of the scapula, and constitutes a harassing symptom of the cases in which it occurs. In this connection it must be pointed out that many of the pains of that obscure condition to which the term spinal irritation has been vaguely applied are myalgic.

Myalgia manifests itself furthermore in the limbs, in the diaphragm, and occasionally in the muscles of the eyeballs.

The COURSE of the attack is in the simpler forms acute and transient; it frequently, however, becomes chronic, and not uncommonly presents the characters of the chronic form from the beginning. Again, it sometimes attacks in succession several muscles or groups of muscles, and in by far the greater number of individuals it shows a tendency to recur from time to time.

DURATION.--The duration of acute attacks is usually brief, lasting from a few hours to several days; that of the chronic form is indefinite, tending to last years, sometimes, under unfavorable circumstances, a lifetime, with varying periods of exacerbation and remission, which are, after the disease is fully established, much influenced by the phases of the weather.

The TERMINATION of acute myalgia is commonly in full recovery, but the tendency to subsequent attacks is to be borne in mind, and guarded {534} against by the exercise of wholesome precautions in the matter of hygiene. Neglected cases of chronic myalgia not rarely terminate in permanent alterations of the muscular structure, with loss of contractile power and rigidity, with or without atrophy.

COMPLICATIONS.--In the acute forms there are no complications, properly so called. In the more severe cases of the chronic form there is danger of nutritive changes in the tissues entering into the formation of joints, and loss of function from want of use.

SEQUELS.--There are no sequels other than those just pointed out.

PATHOLOGY AND MORBID ANATOMY.--As indicated by the various names by which myalgia has been known, the principal theories advanced to account for the morbid manifestations are three in number: (1) that the malady is a rheumatism of the muscles; (2) a form of neuralgia; (3) an inflammation.

(1) Muscular Rheumatism.--That this affection should be popularly associated with rheumatism is not surprising when the character of the pain is regarded, its aggravation on movement, and the temporary or permanent crippling which it occasions; especially when we call to mind the exceedingly vague and indefinite ideas which prevail in regard to rheumatism. But that it should be looked upon, far and wide, among physicians as a form of rheumatism, and described as such in the systematic works--that it should be regarded as due to the same causes as rheumatism and treated from that point of view--is certainly as remarkable as it is misleading.

Let us look at the facts. Nothing is easier: the two affections are under our daily observation side by side; in this climate and among working people few maladies are more common.

On the one hand we behold a constitutional disease with widespread manifestations--a special joint inflammation, which tends neither to the deposit of urate of soda nor to suppuration; a peculiar acid secretion from the skin; highly acid urine; a notable tendency to inflammatory heart complications; marked pyrexia. We observe also a marked disposition to recurrence and to the hereditary transmission of the diathesis.

The phenomena of rheumatism may be ill defined; that is to say, the attack may be subacute, but the features are the same; or they may linger and assume the chronic form, in which fever is replaced by a peculiar alteration in the fluids of the body, showing itself in a dull anæmic complexion and a greasy skin; but in all cases the seat of the disease-signs is in the joints; it is articular.

On the other hand, myalgia is not a general malady nor the expression of one. It is scarcely a disease at all. It is purely local. A muscle or a group of muscles, overworked, cry out, and this cry is interpreted by the sensation of pain. It is to be borne in mind that the overwork may be absolute, or merely relative to the healthfulness of the muscle at the time. In either case there is a derangement between the balance of work and nutrition in the muscle. The secretions are not altered; there is no sweating; the urine presents no abnormal conditions. Endo- and pericarditis never occur as complications; fever is absent.

The attack is often light, and quickly passes away. If it become chronic, further nutritive changes take place. The muscle becomes rigid, and often atrophies. According to Froriep and Virchow, as {535} quoted by Jaccoud[2] and Niemeyer,[3] the fasciculi are beset here and there with thickened connective tissue. Vogel observed in several chronic cases the neurilemma of the nerves supplying the part to be thickened, hardened, and adherent.

[Footnote 2: _Traité de Pathologie interne_, Paris, 1871.]

[Footnote 3: _Lehrbuch der Speciellen Pathologie und Therapie_, Berlin, 1871.]

In all cases the affection limits itself to the muscles. The joints remain free. When they undergo changes it is after a long time and as a result of want of use or of reflex disturbances of nutrition through the nervous system. Nothing is known of hereditary predisposition to myalgia. In the manifest tendency to recur in the same individual it and rheumatism are alike. In all essential points their clinical resemblance is of the most superficial kind. It is clear, then, that the processes which give rise to the phenomena of rheumatism do not directly affect the muscular system.

The credit of having first formulated this opinion, previously only vaguely recognized, is due to Roche and Cruveilhier,[4] but Valleix, Garrod, Flint, and other writers, who describe myalgia under the head of muscular rheumatism, coincide in this view. Even the statement that the two diseases are constantly associated is not borne out by the results of extended clinical inquiries. My own observation has not confirmed it. Of 7 cases[5] taken at random to illustrate a point of treatment, 1 had followed an attack of rheumatic fever; 1 occurred in an individual who had many years before suffered from rheumatism; and 5 gave no history whatever of that disease: 1 followed tonsillitis. DaCosta[6] details 2 cases of myalgia--1 in the loins (lumbago), associated with bronchitis or following it, the other occurring during an attack of rheumatic fever and having its seat in the muscles of the neck. In the latter case the constitutional disease yielded to treatment which had no effect upon the local malady. Even were the association much more frequent than it is found to be, the fact would by no means establish a common causation, seeing that myalgia follows other diseases which impair the nutrition of the body. It is worthy of note that the groups of muscles most frequently involved in cases which happen during or after acute diseases are those which must work perforce--those which maintain the equilibrium of the body or carry on respiration, etc. Hence we see wry neck, lumbago, pleurodynia associated with other diseases; affections of the muscles of the extremities after overwork pure and simple.

[Footnote 4: _Dict. de Méd. et de Chir. prat._, article "Arthrite."]

[Footnote 5: _Philada. Med. Times_, Nov. 7, 1874.]

[Footnote 6: _Penna. Hospital Reports_, vol. i.]

(2) Neuralgia.--Many observers have regarded myalgia as a neuralgia, having its seat in the muscles. Valleix[7] wrote as follows: "Muscular rheumatism and neuralgia have, in the correspondence of their symptoms, their course, their exacerbations, in the absence of appreciable anatomical lesions, the greatest resemblance to each other. These affections often pass the one into the other.... The pain, which is the capital symptom of neuralgia, expresses itself, according to our observation, in three ways: If it remain concentrated in the nerves, characteristic isolated painful points are found; here is neuralgia properly so called. If the pain is diffused among the muscles, muscular action is principally painful; we have muscular rheumatism. Finally, if it be spread out upon the skin, an excessive sensibility of the cutaneous surface results, and there exists {536} a dermalgia. These three forms of an affection which is the same may all be present at the same time, or two and two--neuralgia and dermalgia, neuralgia and rheumatism, rheumatism and dermalgia." No wonder he found nothing more difficult than to trace with exactitude the picture of this malady.

[Footnote 7: _Loc. cit._]

Flint[8] also regards myalgia as closely allied to neuralgia, and states that, "being one of the neuroses, it has no anatomical characters." It is not difficult to trace the results of this teaching in the widespread confusion prevalent in regard to some very common painful affections, as, for example, that painful form of stitch known as pleurodynia, and the still more distressing gastrodynia. Even those observers who refuse to class these affections as rheumatic are too often at a loss as to whether they are neuralgic or purely muscular. Anstie[9] has concisely contrasted the most important characters of neuralgia and myalgia in a way that strongly urges the clinical differences between them, as follows:

NEURALGIA. | MYALGIA.
Follows the distribution of a | Attacks a limited patch or patches
recognizable nerve or nerves. | that can be identified with the
| tendon or aponeurosis of a muscle,
| which, on inquiry, will be found to
| have been hardly worked.
|
Goes along with an inherited or | As often as not occurs in persons
acquired nervous temperament, | with no special tendency.
which is obvious. |
|
Is much less aggravated, | Is inevitably and very severely
usually, by movement than | aggravated by every movement of the
myalgia is. | part.
|
Is at first accompanied by no | Distinguished from the first by
local tenderness. | localized tenderness on pressure
| as well as on movement.
|
Points douloureux, when | Tender points correspond to
established at a later stage, | tendinous origins and insertions of
correspond to the emergence of | muscles.
nerves. |
|
Pain not materially relieved by | Pain usually completely, and always
any change of posture. | considerably, relieved by full
| extension of the painful muscle or
| muscles.

[Footnote 8: _Practice of Medicine_.]

[Footnote 9: _Neuralgia and Diseases that Resemble it_.]

(3) Inflammation.--That the muscular affection under consideration should have been referred to morbid processes of an inflammatory kind is very natural. The use of the term myositis embodies this view, which is held, among others, by Garrod. This author defines muscular rheumatism as "an affection of the voluntary muscles of an inflammatory nature (?), but unaccompanied with swelling, heat, redness, or febrile disturbance." He assigns the combined influence of cold and damp as a cause, especially when associated with over-use of the muscles.

Though some of the gross characters of inflammation are wanting, and the course of acute cases of myalgia is toward a speedy resolution, there are several features of the affection which strongly suggest its inflammatory origin. At all events, the view that the essential pathological conditions consist in a hyperæmia with slight serous exudation, or a partial paralysis of vaso-motor nerves with escape of serum into the intimate tissues of the muscles, has, from a clinical standpoint, much to support it. In the absence of knowledge derived from the actual investigation of the morbid tissue-changes in all the stages of the affection some {537} value is to be accorded to the following facts as confirmatory of this opinion:

It is a local affection; the onset is usually sudden; there is often, from the beginning, a slight but obvious fulness of the muscle; tenderness is present as well as pain; in chronic cases inflammatory increase of connective tissue occurs, with changes in the nerve-sheaths and fatty degeneration of muscle-substance. Moreover, the permanent contraction (contracture) which sometimes finally sets in is the same as that which follows true inflammation of muscles after injuries (traumatic myositis[10]).

[Footnote 10: Erb, _Ziemssen's Cyclopædia_, vol. ix.]

It is uncertain whether the nerves supplying the muscles are thrown into morbid action by changes in the muscular fibres and in their sarcolemma, or by simultaneous changes in their own neurilemma. However it arise, irritation of sensory nerve-twigs is present, giving rise to pain, along with irritation of motor filaments, which occasions spasm.

It is probable that the ultimate cause of the irritation within the muscular mass, whatever it is, is common to all cases, and that when myalgia occurs in a healthy man after extraordinary muscular effort or exposure to cold damp when fatigued, or in a delicate child who has played too long, or in a poorly-fed weaver working long hours over his loom, or in the consumptive whose cough gives him no rest, or in connection with any chronic disease or acute disease, whether tonsillitis or bronchitis or fever or rheumatism, it is the same thing--the expression of muscles or groups of muscles overworked. It is not a disease; it is not a symptom of disease. It is an accident of many diseases--of any disease that lowers nutrition. And it is not less an accident of health when such muscular effort is demanded as is beyond the capacity of health.

The essential pathology of myalgia is obscure. It is not an inflammation, as that term is generally understood, but there is ground for the opinion that the lesions are of the nature of a subinflammatory process within the muscle. The not uncommon instances in which an injury or contusion--in short, traumatism--has been followed shortly after the recovery by severe myalgia are of further value as illustrating this theory.

The obstacles in the way of precise histological investigation in cases of acute myalgia are so great that it seems probable that further knowledge is to be reached for the most part by way of clinical work.

DIAGNOSIS.--The fundamental question for consideration in this place is whether we are dealing in any given case with local manifestations of a constitutional disease or with purely local phenomena. That the latter is the correct view seems to the writer to admit of no further discussion in this article. This position being assumed, and due regard having already been paid to the differential diagnosis between myalgia and rheumatism, neuralgia and inflammatory myositis, it seems useless to enter upon the consideration of the diagnosis between this and other painful affections to which it bears but slight and superficial resemblances. Spinal irritation, hypochondriasis, locomotor ataxia, alcoholism, syphilis, gout, and lithiasis are on the one hand attended by pains which are clearly not myalgic in character, and on the other hand peculiarly predispose those subject to them to this affection of poorly-nourished and easily-overworked muscles. Each of these diseases, however, presents a complexus of {538} symptoms in which that which is essential and characteristic is readily to be distinguished from that which--as myalgia--is accidental.

A few words concerning the diagnosis of some of the varieties may not be amiss.

In pleurodynia the ordinary physical signs of pleural, pulmonary, and cardiac disease are absent, the painful points characteristic of intercostal neuralgia are not found, and there is little or no constitutional disturbance.

The diagnosis of myalgia lumbalis is, as a rule, unattended by difficulty. The muscular pain in the loins is characteristic. It is greatly increased by efforts to rise or to turn in bed, and is associated with diffused slight tenderness upon pressure, but never with the acute localized soreness of neuralgia or abscess. The practitioner must, however, guard against the danger of mistaking the back pains of more serious affections for lumbago by the careful examination, in all cases, of the back and abdomen, and by the investigation of the condition of the urine. The possibility that pain in this region may be caused by spinal meningitis, lumbar abscess from spinal caries, sciatica, inflammatory affections of the hip-joint, renal calculus, perinephritis, abdominal aneurism, diseases of the pelvic viscera, and the onset of certain of the acute infectious diseases must not be overlooked.

PROGNOSIS.--Under satisfactory conditions as regards hygiene and treatment the prognosis is always favorable. It becomes in chronic cases unfavorable as regards complete recovery when by reason of poverty, unhealthy occupations, unwholesome surroundings, or established wasting diseases the nutrition of the muscles and their physiological rest are permanently interfered with, and the balance between their power and work permanently deranged.

TREATMENT.--The indications are threefold: (_a_) relief of pain; (_b_) physiological rest for the affected muscles; (_c_) restoration of the balance between the nutrition of the muscle and the work it has to do.

(_a_) Relief of pain is often secured by rest in a posture that permits the complete relaxation of the muscles involved. In acute cases due to overwork pure and simple, and where complete rest is attainable, little other treatment is required. In the course of a few hours or days the function of the muscles is fully restored and their contractions are performed without pain. Where, however, complete muscular relaxation is impracticable or fails to afford relief, anodynes are necessary. Morphine hypodermically is very useful, but this altogether independently of any local action. Continuous dry or moist heat by means of flannels, flaxseed poultices, spongio-piline, etc. may be applied. Various anodyne lotions are useful. Liniments containing aconite, belladonna, chloroform, or chloral also afford relief. The compound belladonna liniment of the British Pharmacopoeia is especially to be recommended. So also are plasters of belladonna, conium, and mustard. Galvanism occasionally gives prompt relief. The same statement may be made of the use of static electricity. The pain sometimes disappears under gentle and long-continued massage.

(_b_) Rest is usually enforced by the intensity of the pain attending movement. In severe cases the bed is a necessity. In affections of the respiratory muscles, as pleurodynia, firm support of the side, by means of {539} overlapping strips of plaster drawn from the spine downward and forward in the direction of the ribs to the median line in front, is sometimes necessary and always comfortable.

(_c_) The balance of nutrition is restored by rest. Local means to further this end are such as relieve pain--heat, anodyne and stimulating frictions, massage, and galvanism. The parts must be protected from sudden changes in temperature by extra thicknesses of flannel or sheets of wool or cotton batting--if necessary covered with a piece of oiled silk or fine gum-cloth. In old cases prolonged massage with passive movements, shampooing, and the slowly interrupted galvanic current, alternating with rapid faradic currents, are followed by good results.

As a constitutional measure a Dover's powder at night, followed by mild purgation in the morning, is often indicated. Purgation is especially called for in plethoric or gouty persons, in whom also Turkish or vapor baths are of great service, while poorly-nourished, anæmic subjects demand quinine, iron, lime, and cod-liver oil. If the attack linger, full doses of ammonium chloride, and in old cases potassium iodide in moderate doses well diluted and long continued, are advocated; and in stubborn cases Anstie recommends deep acupuncture of the muscle near its tendinous attachment. In cases marked by a tendency to spastic rigidity the repeated hypodermic injection of atropine may often be relied upon as the speediest means of cure.

Where the general nutrition is poor the local trouble is apt to be obstinate, and often yields only to measures that restore the general health.

{540}

PROGRESSIVE MUSCULAR ATROPHY.[1]

BY JAMES TYSON, A.M., M.D.

[Footnote 1: From the view taken by the author as to the nature of the disease under consideration, it is evident that its proper position would be under affections of the nervous system. But as this view has not been established to the satisfaction of all who have studied the disease, it seems appropriate to place it in the intermediate position selected for it by the Editor, between muscular and nervous diseases.]

SYNONYMS.--Chronic anterior poliomyelitis; Spinal form of progressive muscular atrophy; Adult form of progressive muscular atrophy; Wasting palsy (Roberts); Cruveilhier's atrophy; Amyotrophia spinalis progressiva (Erb).

DEFINITION.--Progressive muscular atrophy is a gradually progressive wasting of a group or groups of voluntary muscles, independent of primary functional inactivity and of local lesion to nerve or muscle.

HISTORY.--We are indebted to William Roberts[2] for the best historical account of this disease up to the date of publication of his monograph. Van Swieten seems to have described the first case, in 1754, but without comment. Cooke in his work _On Palsy_,[3] published 1822, relates a case which had been under the care of Cline--that of an officer, first attacked in 1795. Caleb H. Parry[4] reported another case in 1825, and Sir Charles Bell[5] three cases in 1830. Abercrombie described a marked case in 1828,[6] Dorwall[7] three striking cases in 1831, and Herbert Mayo[8] two evident cases in 1836. In 1849, Duchenne presented to the Institute of France his memoir on _Atrophie musculaire avec Transformation graisseuse_. In the next year Aran published his essay entitled _Recherches sur une Maladie non encore décide du Système musculaire_ (_Atrophie musculaire progressive_),[9] in which he claimed priority in description. He reported in all eleven cases, and regarded it as a primary muscular affection. Aran's researches were very important, and have caused his name to be intimately associated with the disease along with that of Duchenne.

[Footnote 2: _An Essay on Wasting Palsy_, London, 1858.]

[Footnote 3: London, 1822, p 31.]

[Footnote 4: _Collected Works_, London, 1825, p. 523.]

[Footnote 5: _The Nervous System of the Human Body_, London, 1830.]

[Footnote 6: _On the Brain and Spinal Cord_, 1828, p. 419.]

[Footnote 7: _London Medical Gazette_, vol. vii., 1830-31, p. 201.]

[Footnote 8: _Outlines of Human Pathology_, London, 1836.]

[Footnote 9: _Archives générales de Méd._, t. xxiv., Sept. and Oct., 1850.]

Cruveilhier's studies were commenced as early as 1832, but his results were not published until March, 1853,[10] when he read his memoir before the Academy of Medicine of Paris. He seems to have made the first autopsy, and was much surprised at the absence of any apparent lesion of the {541} spinal cord. So enthusiastic and so exhaustive was his study of the disease that his name, too, has become almost inseparably associated with it, and the term Cruveilhier's atrophy is one of those by which it is known. He concluded from his earlier autopsies that the lesions were solely in the muscular system, which is progressively destroyed, while the brain and spinal cord may remain perfectly normal. In a later case (his third), terminating January, 1853, he found atrophy of the anterior roots of the spinal nerves, and then concluded that the disease resided "not in the muscles themselves, but in the anterior roots of the spinal nerves." But after the termination of his fourth case, in which an autopsy was also secured, he placed the primary lesion in the gray matter of the cord, whence he considered the anterior roots take their origin.

[Footnote 10: _Ibid._, May, 1853, p. 561.]

Thouvenet,[11] an interne of Cruveilhier's, published in 1851 a thesis based on some cases collected in the Charité, and was the first to claim that the disease resides primarily in the peripheral nerves, and that it must be classed among rheumatic affections.

[Footnote 11: _Gaz. des Hôp._, Nos. 143 and 145, 1851.]

In December, 1851, E. Meryon[12] read a paper before the Medico-Chirurgical Society of London entitled "Granular and Fatty Degeneration of the Voluntary Muscles." His observations appear to have been made quite independently of any preceding researches. He argues that the primary morbid change is a default of nutrition in the muscular fibres.

[Footnote 12: _Med.-Chir. Trans._, vol. xxxv. p. 73.]

Subsequently, cases were published in 1853 by Bouvier, Landry, Burg, and Niepce in France; in 1854 by Chambers in England, Guérin and Robin in France, Cohn, Virchow, and Betz in Germany, and by Schneevogt in Holland; in 1855 laborious essays were published by Oppenheimer, Wachsmuth, and Eisenmann, and cases by Hasse, Valentiner, Virchow, Meyer, and Diemer in Germany, and Gros in France. Duchenne's work on _Local Application of Electricity_, also published in 1855, contains much information on the subject.

Since 1855 the reports of cases and papers on the subject have been so numerous as to make it unprofitable to enumerate them. Among the most notable are those of Eisenmann, published in _Canstatt's Jahresbericht_ for 1856; Roberts's classic work on _Wasting Palsy_, in 1858; the papers of Lockhart Clarke in 1866 and 1867,[13] and of Swarzenski in 1867;[14] Kussmaul's clinical lecture[15] and Friedreich's treatise[16] in 1873; and Eulenburg's article on "Progressive Muscular Atrophy" in _Ziemssen's Cyclopædia of Practical Medicine_, published in German in 1875 and in English in 1877. An important case, in consequence of the careful post-mortem study of the nervous tissues, is one recently reported by Wood and Dercam.[17]

[Footnote 13: _Med.-Chir. Transactions_, xlix., 1866, p. 171, and l., 1867, p. 489.]

[Footnote 14: _Die Progressive Muskelatrophie_, Berlin.]

[Footnote 15: "Ueber die fortschreidende Bulbärparalyse und ihr Verhältniss zur progressiven Muskelatrophie." _Sammlung klinische Vorträge_, liv.]

[Footnote 16: _Ueber progressive Muskelatrophie, über wahre und falsche Muskelhypertrophie_, Berlin, 1873.]

[Footnote 17: _Therapeutic Gazette_, March 16, 1885.]

ETIOLOGY.--The cause of this affection in a large number of cases is quite unknown. That hereditation plays an important part seems well determined by numerous observations, among which may be mentioned those of Roberts, Friedreich, Hemptenmacher, Trousseau, Meryon, {542} Eulenburg, Sr. and Jr., Naunyn,[18] Hammond, and Osler.[19] In the Farr family, reported by Osler, 13 individuals in two generations have been affected, 6 females and 7 males--a larger proportion of the former than is common in this disease. Of these 9 had died at date of publication of paper. With the exception of two, all occurred or proved fatal after the age of forty. Of the 10 instances in the second generation, 5 are the offspring of males and 5 the offspring of females. The disease has not yet appeared in the third generation, which promises between forty and fifty individuals, several of whom are over thirty years of age.

[Footnote 18: _Berliner med. Wochenschrift_, Nos. 42 and 43, 1873.]

[Footnote 19: _Archives of Medicine_, vol. iv., No. 3, Dec., 1880.]

The over-use of the muscles involved seems to be a well-determined cause in certain cases of true muscular atrophy. The following interesting illustrations are given by Eulenburg:[20] Betz observed atrophy of the side three times in the cases of smiths and saddlers, who had to do heavy work with the right hand; Gull, in a tailor after excessive exertion; Hammond reports a case apparently due to excessive use of one thumb and finger in playing faro; Friedreich, one of a dragoon who may have exhausted his left hand in holding the bridle while riding; another in a morocco-leather worker, who used to press hard with his left hand; and a musician who played several hours a day on the bass viol. Schneevogt names two cases of primary atrophy of the shoulder-muscles, especially of the deltoid of the right side--one of a sailor who had to pump for days together on a leaking ship, and the other of the left side in a woman who always carried her child on the left arm while suckling it. Continued threshing and the handling of a musket have both been followed by it in the muscles called into play by these exercises. Roberts was able to trace the effects of over-muscular exertion in producing the disease in 35 out of 69 cases. As a determining cause, at least, therefore, we must admit the over-use of muscles.

[Footnote 20: _Op. cit._]

There is reason to believe, too, that this form of atrophy is one of the consequences of senility--that the tendency to connective-tissue overgrowth which characterizes old age operates to produce, in a way to be presently explained, an atrophy of groups of muscles. In a woman aged seventy, now under my care, the fingers of both hands are clawed--became so inappreciably almost, and the condition is still increasing.

In addition to the above-named causes, long-continued exposure to cold, and especially to the action of very cold water, has been named. Traumatic influences, such as injuries to nerve and muscle, have been called upon to account for localized and progressive atrophy, but these are excluded by our definition from the category of true progressive muscular atrophy.

Cases have also occurred in the course of convalescence. Typhoid fever, rheumatism, measles, scarlet fever, cold during salivation, vaccination, childbed, excessive venery, syphilis,--have all been held responsible for a certain number of cases.

AGE AND SEX.--In examining the literature of acute muscular atrophy it is found that cases are reported at all ages. Thus, Wachsmuth, quoted by Eulenburg, found among 49 cases 13 under the age of fifteen, 8 from fifteen to twenty, 22 from twenty to fifty, and only 6 over fifty years. On the other hand, Roberts--who, following Aran, divides the disease into the general form and partial form--says the latter very rarely falls on {543} individuals under adult age or over fifty, while the average age of the instances of the partial form studied by him was thirty-two years and four months. In 10 instances of the general form the patients were under twelve, and 2 more are reported as children; 1 was said to be sixty-nine and another fifty-four, the average being twenty-eight years and three months. Of Eulenburg's own cases, 7 acquired the disease before the age of ten, 6 before the twentieth year, 2 before the thirtieth, 8 before the fortieth, 5 before the fiftieth, and none later. The latter observer also finds that whenever the disease is hereditary it occurs earlier, usually before the close of the twentieth year. This was certainly not the case in the Farr family, reported by Osler.

I am inclined to believe, especially in the light of Charcot's[21] and of Erb's[22] recent studies, that the true spinal form of progressive muscular atrophy is a disease of adult life, and that the majority of cases reported as occurring in early life are instances either of what Erb calls the juvenile form of progressive muscular atrophy or of pseudo-hypertrophic paralysis.

[Footnote 21: "Revision nosographique des Atrophies musculaires progressive," _Le Progrès méd._, No. 10, 1885, i. 314-335.]

[Footnote 22: "Ueber die Juvenile Form der Progressive Muskelatrophie und ihre Beziehungen zur sogenannten Pseudohypertrophie," _Deutsches Archiv für klin. Med._, xxxiv. 1884, S. 467.]

As to sex, males predominate. Thus, according to Friedreich's statistics, out of 176 cases but 33 were females, or about 19 per cent. Of Roberts's collection of 99, 84 were males and 15 females. Of 28 cases noted by Eulenburg, 17 were in men and 11 women. This is doubtless owing to the fact that men are subjected to the causes of the disease more than women. For Roberts early noted that women who engage in needlework, washing, and household service are apparently not less liable than men similarly employed, and he found that of those whose labor did not press excessively on any particular sets of muscles females formed even a majority of cases.

Some singular freaks of selection have presented themselves in the matter of sex, particularly in the cases which have been ascribed to hereditation. Thus it will sometimes attack only the male members of a family. A remarkable instance of this was observed by Meryon, in which four sons were attacked and six daughters remained unaffected; and, again, two boys were attacked and two sisters escaped. This may occur also independent of hereditation. Occasionally the reverse takes place, the sisters only being attacked, while the brothers escape.

PATHOLOGICAL ANATOMY AND HISTOLOGY.--Two principal seats of change have been found to exist in connection with progressive muscular atrophy. The first and easiest recognized is, of course, the alteration in muscles; the second, that in the nervous system.

The muscular change is simple, and affords a typical instance of what is known as numerical atrophy. The muscular fasciculi one after another undergo fatty metamorphosis, succeeded by absorption of the resulting fat and substitution of connective tissue. The rate of atrophy varies, but sooner or later the muscle is more or less substituted by fibrous bands and cords, over which may be traced reddish lines which represent muscular tissue in a normal state.

The rationale of these changes has not been always the same. The {544} older observers regarded them as the result of a primary fatty metamorphosis of muscular fasciculi, followed by absorption of the resulting fat. Later it was asserted that the atrophy is secondary to a myositis or inflammation of muscle, beginning as a hyperplasia of the interstitial connective tissue in its finest ramifications between the single primitive fibrils. Along with this are seen the results of irritation in the primitive bundles themselves, shown by swelling and multiplication of the muscular corpuscles, proliferation of their nuclei, and sometimes cloudy swelling. Even hypertrophied muscular fasciculi and dichotomous and trichotomous subdivision have been noted by Friedreich.

It sometimes happens that the hyperplastic process in the intermuscular connective tissue is succeeded by a fatty infiltration of the cells of the connective tissue, and there results a lipomatosis which is invariably outside of the muscular fasciculi and between them. This gives rise to an appearance of hypertrophy which is only apparent, for the muscular fasciculi are themselves wasted, and proportionally paralytic. This is seen to occur particularly in the muscles of the calves of the legs, in which is produced an appearance identical with that in the disease known as pseudo-hypertrophic muscular paralysis, with which, indeed, the condition under consideration is considered by some identical. But although we must admit in certain cases a complication of a certain degree of lipomatosis with progressive muscular atrophy, the two diseases are essentially different; and it is quite likely that in some instances pseudo-hypertrophic muscular paralysis has been mistaken for progressive muscular atrophy.

The changes in the nervous system are not nearly so simple. They have been noted in the peripheral nerves, both in their trunks and in their intermuscular branches; in the anterior roots of the spinal nerves; and in different parts of the spinal cord, including the central gray matter, the antero-lateral and posterior columns; also in the sympathetic system. These nerve-changes are not simultaneous, nor have they been discovered in every case. It is a noteworthy fact, however, that as methods of examination have improved and the manipulative skill of observers has increased the number of negative cases has diminished.

First, as to alterations in peripheral nerves in their ultimate distribution: The character of these is of a kind usually described as irritative; that is, there is a hyperplastic process in the connective-tissue sheaths (neurilemmæ) and their internal prolongations, consisting in nuclear proliferation and thickening of the tubular membrane or sheath of Schwann. Varicose distortion of the medullary sheaths and their subsequent disappearance, together with destruction of the axis-cylinders, also occurs.

The changes in the peripheral nerve-trunks, as studied in the median, ulnar, radial, and musculo-spinal, are essentially the same, resulting in thinning of the diameters of the nerves. These changes, however, are by no means constant.