This affection, which was very clearly described for the first time by Thomsen, a physician who was himself a victim, belongs to the class of primary diseases of the muscular system. Thomsen de scribed it as a tonic spasm of the voluntary muscles consequent upon an hereditary psychic disposition, but we have no facts which would authorize us to refer the symptoms to any anatomical lesions other than those of a muscular nature.
Although this disease had been referred to in previous works, it was not until 1876 that Thomsen, a physician of Kappelu iu Sleswig, gave us a complete description of it based upon an exhaustive study of his owu case. Since that time there have been many memoirs upon the disease, among others those of Erb, Ballet, and Marie. The two latter writers have defined the disease as consisting in muscular spasms occurring at the commencement of voluntary movements. This singular affection is referable to one essential etiological factor, viz., heredity. Dr. Thomsen had among his ascendants several per sons affected in the same way as himself. According to the statis tics, women would appear to be less liable to suffer from the disease than men. As indicated in the definitions given by Thomsen, Ballet, and Marie, the disease is a spasmodic one. Whenever the subject wishes to execute a movement, immediately the group of muscles whose action is necessary for the carrying out of his intention be comes stiff, and there is a momentary spasm which prevents all movement. Then gradually the rigidity disappears, the spasm relaxes, and the desired movement may be executed. The muscles of the lower extremities are as a rule more affected than those of other parts of the body, the greatest difficulty being experienced when the patient attempts to rise from a sitting posture or begins to walk. There is then a period of complete inability and the patient is forced to wait until the spasm relaxes before carrying out his design. After the spasm has relaxed and the movement is once begun there is noth ing abnormal to lie observed; but the whole trouble may be very easily caused to reappear, a mere change of direction, for example, being sometimes sufficient to excite another spasm. It is in military life that contractions of this kind have been most frequently observed. During drill the spasms are continually recurring, showing them selves each time a command is given to march or turn or make any other change in the order of movements. The condition is further aggravated by the mental disturbance caused by the knowledge that the orders of the commanding officer must be executed.
The muscles of the trunk, the neck, the jaws, the tongue, and the upper extremities may also in individual cases be implicated.
What do we discover here as regards the condition of the muscles? In the first place there is an hypertrophy, without, however, any in (Tease in strength, rather on the contrary a diminution. During the occurrence of the spasm the muscles stand out prominently under the skin and give an impression of hardness to the hand. It. is only the
voluntary muscles that are affected. The reflexes are as a rule nor meal. Examination to determine the condition of the mechanical and electrical excitability of the muscular tissue has given interesting re sults. Erb has shown the mechanical excitability is greatly increased, the least touch being sufficient to excite a muscular con traction. The electrical excitability, both galvanic and faradic, is also increased. But the excitability, galvanic, faradic, and mechanical, of the nerves is rather diminished than augmented. To these altera tions in muscular and nervous excitability Erb has given the name of myotouic reaction.
The diagnosis presents in general no difficulty if we bear in mind the clinical features which we have just sketched. In pseuclo-hyper trophic paralysis, in which there is an apparent increase in volume of the muscles, there are never any spasmodic contractions. Hys teria is easily recognized by the other symptoms accompanying this condition, and besides the spasms do not yield with the same rapid ity that they do in Thomsen's disease. The same applies to locomo tor ataxia, in which the spasms are continuous.
As I have said before, the affection is a congenital one, the first. manifestations of which appear usually in childhood or early youth. In many cases it seems to be associated with peculiar mental states, melancholia or hypochondria, and it was this that led Thomsen to look upon the affection as the consequence of an hereditary psychic disposition. The progress of the disease is very slow, but it may be accelerated by fatigue and overwork. Although an incurable disease it never compromises the life of the individual.
Up to the present time no lesions other than those of the muscles have been discovered, and in an account of an autopsy in a case of this disease which Dejerine and Sottas made to the Societe de Bio logie as late as June 21st, 1893, no mention is made of any changes in the central nervous system. Microscopical examination, according to Erb, Deleage, and Ouanoff, shows changes in the muscular fibre, but few in the interstitial connective tissue. The muscular fibres are hypertrophied, the striations are less distinct, and the normal proto plasm is gradually replaced by a granular material. If there is any change whatever in the interstitial connective tissue it is at most a slight hyperplasia.
disease is resistant to all therapeutic measures, and no remedy has been found that is of the slightest benefit. Nevertheless it will be well to advise the patients to submit to systematic gymnastic exercises and methodical massage, in the hope that some benefit may accrue at least to the general health. Some authors, Erb in particular, have recommended the employment of electricity, either galvanic or faradic. But whatever measures we take we shall seldom be able to relieve the distress caused the patient. by this spasmodic affection which deserves the name of infirmity rather than disease.