toms 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 disturb

ance.

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 mass

age.

ment.

(b) Rest is usually enforced by the intensity of the pain attending moveIn severe cases the bed is a necessity. In affections of the respiratory muscles, as pleurodynia, firm support of the side, by means of

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.

PROGRESSIVE MUSCULAR ATROPHY.'

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

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.

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HISTORY.-We are indebted to William Roberts2 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, published 1822, relates a case which had been under the care of Cline-that of an officer, first attacked in 1795. Caleb H. Parry reported another case in 1825, and Sir Charles Bell' three cases in 1830. Abercrombie described a marked case in 1828,6 Dorwall three striking cases in 1831, and Herbert Mayo 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), 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.

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

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. London, 1822, p. 31.

2 An Essay on Wasting Palsy, London, 1858.

Collected Works, London, 1825, p. 523.

The Nervous System of the Human Body, London, 1830.

On the Brain and Spinal Cord, 1828, p. 419.

London Medical Gazette, vol. vii., 1830-31, p. 201.

8 Outlines of Human Pathology, London, 1836.

Archives générales de Méd., t. xxiv., Sept. and Oct., 1850.

10 Ibid., May, 1853, p. 561.

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.

Thouvenet,' 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.

In December, 1851, E. Meryon2 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.

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 1867,3 and of Swarzenski in 1867; Kussmaul's clinical lecture and Friedreich's treatise 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."

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, 2 Med.-Chir. Trans., vol. xxxv. p. 73.

1 Gaz. des Hóp., Nos. 143 and 145, 1851.

Med.-Chir. Transactions, xlix., 1866, p. 171, and 1., 1867, p. 489.

Die Progressive Muskelatrophie, Berlin.

5"Ueber die fortschreidende Bulbärparalyse und ihr Verhältniss zur progressiven Muskelatrophie," Sammlung klinische Vorträge, liv.

Ueber progressive Muskelatrophie, über wahre und falsche Muskelhypertrophie, Berlin, 1873. Therapeutic Gazette, March 16, 1885.

Eulenburg, Sr. and Jr., Naunyn,' Hammond, and Osler.2 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. 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: 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 moroccoleather 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.

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 indi1 Berliner med. Wochenschrift, Nos. 42 and 43, 1873. Archives of Medicine, vol. iv., No. 3, Dec., 1880.

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Op. cit.