The facio-scapP?lo-homeeal type belongs in general also to childhood but has been known to develop in adolescence, adult life, and almost in old age. It is characterized by a primary symmetrical atrophy of the muscles of the face (orbicularis, palpebrals, and labials). This atrophy naturally produces a special facies, as a consequence of which the disease may readily be recognized by simple inspection alone. Landouzy and Dejerine have drawn a very accurate picture of the appearance presented by these patients. They have described the gaping hebetudiuous air, the immobility of the features, the incom plete closure of the eyes, the half-opened mouth, the projecting lips, and the widening of the buccal opening when laughing, so that the patient is said to laugh "all across his face." The atrophy may remain for a long time limited to the muscles of the face, and it is usually only after a long period that the muscles of the shoulder and arm are invaded. Later the muscles of the fore arm and hand, and finally those of the lower extremity, are seen in turn to become atrophied. The power of sensation persists, and the reflexes and electrical reactions remain as long as there is any mus cular tissue.
In the Leyden-.11obilts the atrophy may begin in the muscles of the lower extremity, mounting from the legs to the thighs, the lumbar region, and finally attacking the upper extremities. This form resembles in its course pseudo-hypertrophic paralysis, but it differs from it in that there is less apparent increase in volume of the affected muscles.
The Zimmeilin type: includes those cases in which atrophy is most marked iu the upper half of the trunk and in the upper extremities, not attacking the lower extremities until later.
The lemoro-tibial type of Eichhorst commences with atrophy of the lower extremities, principally of the interossei and the triceps cruris. As the disease advances the lesion invades the lower part of the trunk and finally the scapular region and arms.
The Brossard- type resembles the last, but is distinguished from it by the fact that there is retraction en griffe of the toes.
course of progressive atrophic myopathy is usu ally very slow, and we may say that the prognosis, at least in those forms in which the atrophy affects chiefly the upper parts of the body, is more favorable, or rather that the end is much further off, than in pseudo-hypertrophic paralysis. Indeed, as long as the lower extremities are not invaded the patients can walk about, take exer cise, are not confined to the bed or even the room, and are thus in much better hygienic conditions than those whose legs are paralyzed. It is thus easy to understand that they have a greater resisting power, and we may see persons affected with these forms of myo pathy surviving for thirty or forty years or even longer. In atrophic, as in pseudo-hypertrophic, myopathy death usually results from gen eral cachexia, organic disease, or frequently from tuberculosis.
The diagnosis of atrophic myopathy will rest not so much on the presence of atrophy as on the peculiar course of the disease. In the most common form, that belonging to the Landouzy-Dejerine type, the atrophy of the muscles of the face, and the peculiar appearance presented by the patient in consequence, will hardly permit of con founding the disease with progressive muscular atrophy or with in fantile paralysis. When the disease appears under one of the other forms which I have described, the diagnosis may be more difficult.
In the case of those whose lower extremities are first affected, and those presenting the scapula-humeral type (Erb), there may be some uncertainty. The first may be thought to be suffering from paralysis with atrophy of toxic origin (alcoholic) or from some form of mye litis; the second may suggest atrophy either of myelopathic origin or consecutive to an articular lesion. I have said that the muscles of the face are often affected in this type, and this may be of aid in arriving at a correct diagnosis. In all cases, whatever the form, we may generally make a diagnosis by studying the commencement and course of the disease and noting the absence of fihrillary contractions and of the reaction of degeneration.
As regards treatment, I have nothing to add to what has already been said in speaking of pseudo-hypertrophic paralysis.
After having passed in review the symptoms and course of pri mary myopathies we cannot help calling attention to the fact that there are still many obscure points about the disease. Thus all the organs have been investigated to determine the cause of these sym metrical lesions, and these researches have led to many interesting discoveries. The troubles have been referred among other cruses to malformations of the osseous structures. In addition to the antero posterior flattening of the thorax noted by Dejerine, to the great fre quency of fractures of the long bones to which attention has been called by Halleou, the occurrence of deformity of the cranium in the sub jects of myopathy has also been described. Marie especially has studied these cranial deformities. The existence of these malforma tions, the nervous system being intact, would justify the hypothesis that primary myopathies are hereditary diseases affecting the mus cular system; the muscles are, as it were, congenitally deformed ; there is something wanting in them, the lack of which gives occa sion later to the appearance and development of the disease. The general belief at the present time is that the affection is a purely muscular one, but certain writers, among them Erb and Lepine, would regard a muscular dystrophy as a disease of nervous origin— a trophoneurosis. As I have already intimated, this is the opinion which I personally hold, and I believe that the future will see many changes in the chapters on the pathological anatomy and patho genesis of these affections.
Before closing this chapter on the primary myopathies, I desire to say a word concerning the muscular atrophy of the type Churcot Marie, not because I regard it as a muscular disease, for it belongs distinctly to the atrophies of nervous origin, but because certain authors have considered it as a transition form between essential myopathies and the myopathies clue to nervous lesions. In its symptomatology and course this affection is certainly related to the myopathies which we have just been studying. The atrophy affects the lower extremities first and does not reach the upper parts until much later. It begins also during childhood, and often several chil dren of the same family will be attacked. alongside of these re semblances there are very wide differences. I have no intention to describe the symptomatology of this nervous affection here, and as re gards the pathology it will suffice to say that the autopsy shows un deniable evidences of medullary lesions.