St. Vitus' Dance (Chorea) is a disease attended by irregular spasmodic movements of voluntary muscles. It occurs chiefly among children from the beginning of the second teething to the age of fifteen, and is more fre quent among girls than among boys. It may occur, though it is uncommon, iu adults. A curious relation exists between chorea, acute rheumatism, and heart-disease. Rheumatism is well known as a most common cause of heart-disease, and heart-disease is frequently associated with St. Vitus' Dance. Moreover, rheumatism seems to be able to descend from parents to children, and it has been found that the children of rheumatic parents, instead of rheumatism, may manifest chorea or heart-dis ease, or both combined. Fright is a frequently alleged cause.
The symptoms in the fully-developed case are remarkable. The patient has no proper control of muscular movements. He cannot keep himself still. The shoulder is hitched, the arm moved about, the fingers twitching. All sorts of grimaces and contortions are pro duced by spasmodic movements of the muscles of the face. The movements cease during sleep. When the person attempts to do some. thing, to grasp some object ,held out, or to carry anything to the mouth, the jerks be come excessively marked. One failure follows another. The hand is nearing the object when it is suddenly twitched away in one direction and then in another, and the case may be so bad that he is unable, after numerous attempts, to effect the desired purpose. Efforts, specially if anyone is watching, seem only to increase the difficulty. Similarly spasmodic movements of the leg produce in walking a jerky, un certain, jumping gait. Speaking is altered, becoming hesitating or drawling. In extreme cases chewing and swallowing are also seriously affected, and swallowing may become impos sible. The case under these circumstances is easily recognized. But the disease comes on slowly, and may at first manifest itself only by slight twitehings of the muscles of expression. Children may be supposed to be grimacing on purpose, and may be punished while they arc innocent. The child usually suffers in general health, becomes dull, and avoids companions, probably often because of the derision with which he is ignorantly treated. Fretfulness, timidity, restlessness, and clumsiness of gait and movement may be the ways in which the disease first shows itself.
The affection may be only one-sided ; but, if it be general, one side is usually worse.
Recovery may take place speedily in the course of a few weeks, or it may be prolonged for two or three months or even for years. The cases where swallowing becomes affected. and those in which the heart is involved, are very serious.
The treatment consists first of all of atten tion to the general health. Let the bowels be put in order ; let the food be light and nourish ing. Fresh air, early hours, gentle exercise, mild gymnastics if possible, tepid sponging, especially with salt water, sea air also, if pos sible, are invaluable. The child should not be subjected to the annoyance of rude compan ions. At the same time it must not be petted and spoiled at home. Notice must not be taken of its peculiarity. Of medicines, tonics are best, the chief being iron and arsenic ; but these should be used under the guidance of a medical man, especially arsenic, whose adminis tration, because of certain peculiarities in its action, requires great care. If such guidance cannot be obtained, the two drugs may be given together, one drop of Fowler's solution of arsenic, and three drops dialysed iron in water after meals four times a day. This may be slowly increased to two drops of the arseni cal solution and five of the iron. If sickness, pain in the stomach, irritation of the eyelids, and silvery-looking tongue are produced, these indicate that the dose must be reduced. The dose must be reduced slowly, never suddenly. For arsenic should always be administered in small doses, slowly increased, and when it is desired to atop its use the dose must be as slowly decreased till it can be gradually aban doned. A caution is necessary. Chorea some times spreads by imitation. Children may exhibit the spasmodic movements from watch ing another affected with the disease.
Tetanus (lock-jaw) is a disease of a spas modic character in which, however, the spasms do not yield and then recur as in convulsions, forming what has been described as the clonic spasm (p. 180), but in which the spasms con tinue, causing stiffness and rigidity of the affected muscles, forming the tonic spasm.
Its causes are usually injury, sometimes simple bruises or cuts, but more frequently injuries accompanied with great destruction or crushing of parts of the body. It is, moreover, injuries obtained under circumstances that prevent their proper treatment that are most liable to occasion the disease. Tetanus is thus found among the wounded in war, whose wounds have been contaminated by earth or dirt, and without speedy opportunity of being cleansed. The real cause, however, is an or ganism—a bacillus—which gains access to the wound and flourishes on it, producing a poi sonous substance or toxin (see Vol. I., pp. 416, 513). The organism does not spread beyond the wound ; but the poison it produces is ab sorbed by the blood and lymph channels, but mainly by the nerves, and acts specially on the spinal cord.