Towards the end of the disease contraction and shortening may occur in certain muscles—usually in those the opponents of which are exces sively enfeebled. This is a phenomenon which is seen in other forms of paralysis, and its mechanism is discussed elsewhere (see page 375). There is, however, one form of contraction which has been said by Duchenne to be a constant symptom of pseudo-hypertrophic paralysis. This is seldom noticed before the end of the sixth year. It takes place at an earlier period than the ordinary paralytic contractions, and occurs as a conse quence of shortening in the length of the diseased gastrocnemii. These muscles draw up the heel so that the patient cannot press this part of his foot to the ground, and as the contraction increases a talipes equinus is developed. The deformity is usually symmetrical. When combined with the muscular weakness it makes walking very difficult. Consequently there is nothing to oppose further contraction, and the extension of the ankle soon becomes extreme.
The disease may be associated with idiocy and mental feebleness, as appears from some cases published by Dr. Langdon Down, and with epi lepsy and other forms of cerebral deficiency and disturbance. But these do not appear to be an essential part of the disease ; indeed, in most re corded cases the cerebral functions have been unimpaired.
The course of the disease is fairly constant, and the age at which the illness reaches its fatal termination varies, as a rule, according to the age when the symptoms first appeared. Thus, if the symptoms have occurred in infancy, the power of standing is lost about the tenth or twelfth, and death ensues between the fourteenth and eighteenth years. If the early symptoms have been delayed until the sixth or eighth year, the patient is less incapacitated by the time puberty is reached, and may live to the age of nineteen or twenty, or even longer. Still, sometimes the disease runs a shorter course, and it may happen that although late to appear the symp toms developc rapidly, and the patient quickly loses all power of support ing himself upright. Even in the fatal cases death is only indirectly the consequence of the hypertrophic disease. When the muscles of the chest become attacked, the inspiratory power is greatly enfeebled, and any acci dental lung complication soon assumes alarming proportions. In fact, it is usually to bronchitis or pneumonia that the fatal termination is to be directly attributed.
Diagnosis.—Inordinate size and firmness of muscle combined with ex treme weakness and unsteadiness, developing slowly, and becoming grad ually more and more marked, without cerebral symptoms, impairment of sensation, or weakness of the bladder or rectum, are the most characteristic features of the disease. The peculiarities of attitude and gait are also to be noted. The position of the child, as he stands with his feet widely apart, his abdomen protruded and his shoulders thrown back, his rolling gait in walking, and his method of helping to straighten the knees by pressing with his hands upon the femur just above the joint, must not be overlooked.
Hypertrophy of the muscles is not always present. Largeness and hardness, of the calves are very characteristic, but scarcely any less charac teristic are their contraction and wasting with drawing up of the heels.
Dr. Gowers attaches great importance in diagnosis to the increased size of the infra-spinatus muscle, with wasting of the latissimus dorsi and lower part of the pectoralis major.
There is little difficulty in distinguishing the disease from infantile spinal paralysis, which comes on quite suddenly, in which the paralysis, at first general, quickly limits itself to certain muscles, faradic contractility early disappears, and wasting is rapid and extreme ; nor from spasmodic spinal paralysis, in which spasm is a marked feature, with great rigidity of joints and exaggeration of the tendinous reflexes. It is more difficult to decide between this affection in its early stage and cerebellar tumour, or the indefinite beginning of intracranial disease in well-nourished children —cases where sometimes all that can be detected is that the child is giddy and falls about. Still, in pseudo-hypertrophic paralysis the attitude is un mistakable, and the way in which the child rises from the ground can scarcely be misinterpreted. Progressive muscular atrophy is so excessively rare in childhood that it may be left out of consideration. It differs mark edly from the disease we are considering by being never attended by muscular pseudo-hypertrophy, and by invariably beginning in the upper part of the body. In a child seen by Duchenne it began in the face.
Prognosis.—When the disease is confirmed we can scarcely hope by any remedial measures to stop the progress of the muscular change. If the patient be seen at an early period of the attack, before any enlargement of the muscles has been noticed, treatment is said to afford more hope of success. In estimating the chances of a lengthened course we must take into consideration the period at which the first symptoms were noticed, the rate at which the affection is advancing, and the age and sex of the patient. According to Dr. Gowers, the progress of the disease appears to be often related to the process of growth ; therefore the less the muscular change has advanced at a period when the growth of the body is com pleted, the greater the likelihood that the disease will become stationary. As a rule, when it appears late it advances slowly. Therefore in the most favourable cases the affection has appeared late, and has advanced but little at the time of full growth of the body. As these conditions are more often found united in girls than in boys, the female sex is in itself a favourable element in the prognosis.
Treatment.—There is little to be done in the way of treatment. Du chenne states that he has succeeded in arresting the disease in two cases by means of faradism, kneading and shampooing the muscles, and the use of baths. Benedikt recommends the continuous current. Arsenic and phos phorus given internally have been thought to be useful by some. Supports to the spine are of service when there is great weakness of the back, and in cases of marked contraction of the calf muscles the tend° Achillis has been divided with great temporary advantage.