Still another myopathic condition, which in the light of modern knowledge has to be separated from progressive muscular atrophy, is Duchenne's hereditary infantile atrophy. This is characterized by onset at an early age and by its beginning in the facial muscles. Its clinical features are thus described by Charcot29 and his pupils Marie and Guénon.30 Although it mostly begins in infancy, it may not come on until adolescence, or even until middle or advanced age; it is often hereditary; the face-muscles are first involved, particularly the orbicularis oris, and there is a peculiar expression of the countenance; whistling is impossible, and the articulation of labials difficult; the eyes cannot be completely closed or the eyebrows raised. Subsequently other muscles become involved, particularly those of the shoulder girdle, except the deltoid, the muscles of the arm, the long supinators of the forearm, and in the lower extremities the muscles of the buttocks, thighs, and of the anterior external aspect of the leg. The muscles of the hands and fingers are spared. Fibrillar tremors are not present, and there is no reaction of degeneration. The distribution of the atrophy is almost identical with that of Erb's form, except that it begins in the face. It is likewise an hereditary or family disease.
29 Le Progrès médical, No. 10, 1885.
30 Revue de Médecine, October, 1885.
PROGNOSIS.—The course of progressive muscular atrophy is never rapid—essentially chronic. Recovery in a well-established case is not to be expected, although it is rare for any one to die of the direct effects of the disease. It is often arrested in its course, and remains at a standstill for years. The wider its distribution and the more numerous the foci of involvement, the more rapid is its course; and when the muscles of deglutition and respiration are involved, and the carrying back of food interfered with, death from asphyxia is liable to be produced by the entrance of food into the larynx or from the accumulation of mucus in what under ordinary circumstances would be a slight catarrh of the respiratory passages.
TREATMENT.—Treatment directed specifically to the cure of the disease is limited. Only where there is reason to believe that syphilis is responsible for it do we find an opportunity to strike at the fons et origo mali by mercurials and iodide of potassium. Yet in Cooke's case, quoted by Roberts,31 the disease after progressing continuously for five years, during which a variety of modes of treatment was tried, had its further progress stopped by a course of mercury, although no cause of the disease could be assigned.
31 Op. cit., p. 1; also Cooke On Palsy, Lond., 1822, p. 31; also quoted by Graves in his Clinical Lectures, L. lxxxiii.
In the majority of instances treatment must consist merely in efforts to maintain the general health and strength of the patient and to counteract the obstinate tendency of the spinal disease to produce wasting of the muscles by depressing their nutrition. The former is accomplished by an abundance of nutritious food, fresh air, and out-door life, by gymnastics, chalybeate and other tonics, including arsenic, strychnine, and quinine. The second is attained by electricity, frictions, and massage. Both forms of electricity are useful, the induced current with rapid interruption with a view to counter-irritate and to stimulate the circulation, or by slow interruptions to stimulate individual muscles to contraction, and thus maintain their nutrition. Duchenne recommended the application of currents of moderate intensity, with not too frequent interruptions, and for a few minutes only at a time, so as not to fatigue the fibres undestroyed. He urged particularly the treatment of important muscles like the diaphragm through the phrenic nerves, of the intercostals, and of the deltoids before they were actually invaded by the disease. He relates the case of a man named Bonnard who had lost many of his trunk-muscles, and who was beginning to suffer with dyspnoea, on whom faradization of the phrenic nerves, repeated three or four times a week, was of great service, enabling him to walk considerable distances and to go up stairs without fatigue. Another patient, whose arms were much wasted, was so far restored that at the end of six months he was again able to support his family.
The direct current—galvanism—is useful in advanced stages of the disease, where even the strongest faradic currents fail to produce response. Even where galvanic currents fail to exert contractions the treatment ought to be persevered in for a long time. It may be necessary to use very strong currents at the outset, which may be gradually weakened as contractility returns.
Remak, who especially advocated the use of the continuous current, advised to place the positive pole in front of one mastoid process and the negative pole on the opposite side of the neck near the spinous processes of the vertebræ, not higher than the fifth cervical, by which he produced the contractions already described as diplegic in the fingers and other paralyzed parts.
Galvanization of the sympathetic has been apparently useful in the hands of some—viz. Roberts, Benedikt, M. Meyer, Guthzeit, Erb, Neseman, and others, while the latter reports a case of complete cure by this treatment. Eulenburg tells us, however, that a relapse is said to have occurred in this case; also that neither he nor Rosenthal have had any results from it.