A form of degeneration of the structure of the muscles is recognized, which is nutritional in character and in which the nerves or the nervous system are not involved, being positively in the muscles themselves. These changes are apt to occur early in life, and seem to be due to inherent lack of vitality in the muscles or to an imperfect development of the muscles. They may follow direct injuries or result from protracted infectious fevers, but these causes are probably the inducing causes only when the predisposing condition is present.
The muscles waste away, become shortened and pigmented, or a deposit of fat cells within the sarcolemna takes place, or the fat may be also deposited between the sheaths. On the other hand there may be actual enlargement of structure with progressive loss of power. This is due to an actual hypertrophy of the fibrillae or to an overgrowth of connective tissue.
The form known as pseudo muscular hypertrophy is characterized by a peculiar enlargement of the muscles of the calves in children usually occurring before the age of eight years. With this enlargement the patient walks imperfectly and with much effort, stumbles and falls over trivial obstacles and is quickly tired from the effort. The muscles of the front of the thighs soon show enlargement out of proportion to the normal development of the muscular system of the child. With this, however, there is apt to be atrophy and weakness of the muscles of the back and of the gluteal muscles exhibiting itself in a protruding belly and more or less anterior spinal curvature. As the disease progresses it involves other groups of muscles. Sometimes the atrophy is apparent and sometimes fatty or albuminoid degeneration induces hypertrophy. The disease often induces permanent contractures of groups of muscles. There is no disturbance of the reflexes nor usually of the sensation.
That form of progressive muscular dystrophy known as Erbs juvenile dystrophy begins usually about the age of puberty and affects the muscles of the shoulders, including the pectoral and deltoid muscles, the trapezius muscles, the rhomboids and the latissimus dorsi. These become very weak as the hypertrophy progresses, permitting the shoulders to fall forward with perhaps, ultimately, spinal curvature. The shoulder blades are very conspicuous. The disease may progress until the gluteal muscles and the muscles of the thigh and calf may also become affected. This is not widely different from the pseudomuscular type, except that it occurs a little later in life.
There is still another type of dystrophy which is designated as the Landouzy-Dejerine type, in which degeneration involves the muscles of the face, arm and shoulder. It begins in the muscles of the eyelids and mouth, materially changing the facial expression and resulting in an expressionless or stupid appearance. It may affect the muscles of the eyeball, resulting in loss of control. Fortunately it does not readily attack the masseters, although there is difficulty in closing the lips, and as a result there is a dribbling of the saliva. It ultimately involves the muscles of the arms and shoulders and may finally progress until it includes the other dystrophies previously described. This condition is distinctly hereditary and shows itself in both males and females between the ages of six and sixteen years.
Prognosis:—The prognosis in all of the forms of atrophy and dystrophy is not good as to recovery, but while usually progressive there may be a stay in their progress and with more or less deformity the patient may live for years.
Treatment:—The treatment of all forms, either of atrophy or dystrophy, is by no means specific. In those cases which are undoubtedly hereditarily transmitted there will probably be but little benefit from the treatment. It would be much better for the members of these families not to marry, as the children are of more or less imperfect muscular development usually. If a systematic course of massage and muscular exercise, which should in no case be weakening, could be laid out for these patients from early infancy, there is no doubt that much benefit might be obtained.
The nutrition and general muscular and nervous tone of all of these patients must be encouraged. They must be built up until they are in the very best possible physical condition. For this purpose the digestive and appropriative organs must be kept in a normal condition and a systematic plan of diet must be laid out, from which condiments and pastries are excluded. Those in whom the disease develops from overwork should not necessarily adopt a life of inactivity, but a change of employment is necessary. They should follow some course which will involve other groups of muscles or the entire muscular system, except the wasting muscles.
They should spend their time largely out of doors and in the sunshine, in a mild climate. Those remedies which improve the muscular structure and muscular system should be selected. The calcium phosphate and the magnesium phosphate, or free phosphorus, when there are sufficient lime salts in the system, will be the first remedies that will be demanded. To arouse the muscular fibrillae, as well as to stimulate the central nervous system, hydrastin and strychnin will be demanded. In other cases the strychnin arsenate will be a most serviceable remedy. The zinc phosphid may be given for a considerable period with good results. The doses should be small with children and repeated every two or three hours. The cupric arsenate in one-hundredth grain doses three or four times daily will benefit some cases.
By all means the most serviceable measures will be massage, systematic muscular movements, vibration and the electrical current. In the application of this current each patient must be studied separately. In some of these the galvanic current will be of benefit, others may be treated with the spark, others with the electric shower, while still others will receive benefit from the faradic current. A very mild current persisted in for a long time has been more satisfactory with me than any other course, some marked acquired cases having been thus cured.