This twitching affection, so familiar that it need not be described particularly, is sometimes classed as a pure neurosis, sometimes as a nervous disease with perhaps some organic basis and sometimes is placed among the ailments related to rheumatism and attributed to some pathological condition of the circulation.

Etiology.—Two elements must be considered in the problem of the etiology {562} of the disease—the predisposition and the direct occasion. The affection occurs particularly in nervous children who are made to occupy their intellects too much while their muscular systems are kept quiet for long hours. Often a preceding running down in weight is noticed, though sometimes the child only fails to increase in weight as it should in proportion to its growth. It occurs quite frequently among chlorotic girls just before or about the time of puberty. Anemia generally seems to predispose to it, but the affection may occur among children who seem to be in excellent physical health, though usually a distinct nervous heredity is found.

Immediate Causation.—Fright is one of the most frequent immediate causes or occasions of the development of chorea. Mental worry of any kind may have the same effect. Scolding has produced it; a sudden grief has seemed to be the occasion; a slight injury, and still more, a severe injury, or a surgical operation, even a slight one, may be the forerunner of it.

Pathology.—No definite lesions have been found to which the disease can be attributed, though a careful search has been made for them. Endocarditis is an extremely common accompaniment. It is probably present in three-fourths of the cases that have come to autopsy. Osler found it in sixty-two out of seventy-three cases in the literature. The association of the affection with rheumatism is insisted on by the French and English particularly, and certainly in a considerable number of cases there is a history of preceding or coincident rheumatism, that is, an acute rheumatic arthritis. Often these attacks are concealed under such names as "growing pains" or "colds in the joints" but it is not hard to elicit a history of a red and swollen joint with some fever. In children mild cases may occur of genuine acute rheumatism with the involvement of but a single joint and that not severely. These mild forms are often found in the history of cases of chorea.

It seems likely that the heart affection is often responsible for the symptoms and it is probably through the endocarditis that whatever connection there is between chorea and rheumatism exists.

All the elements in the disease point to the influence of the mind over it. The predisposition is caused by over-use of the mind at a time when many claims are being made on the nervous system because of the growth of muscles. There must, as a rule, be a pathological basis, natural or acquired, that is, something that tends to produce a defect in the circulation, but even without this certain children suffer from the affection. If the patient is an object of solicitude or of curiosity at home or at school, the symptoms rapidly become worse. At any time the consciousness of observation makes them worse. The symptoms do not occur during sleep, or at times when the patient's mind is much occupied with some absorbing interest. They lessen just to the degree that the patient's own attention is not called to them or the consciousness not allowed to be concentrated on them. Chorea often occurs in bright, intelligent children and always seems worse in them.

Treatment.—The story of the therapeutics of chorea in recent years strongly confirms the idea of the place of mental influence in the cure of the disease. We have had a whole series of remedies, introduced with a promise of cure by distinguished authorities, used for a time with apparent success by many physicians, and then gradually falling into innocuous desuetude. It was recognized that any remedy would have to be used over a rather {563} prolonged period, at least from five to ten weeks. It was appreciated, also, that the patient must be kept quiet, both in mind and body, emotional disturbances especially being avoided, that all physical functions have to be set right and that the nutrition particularly must be corrected if in anything it is abnormal. Where all this is done patients recover without any remedy quite as promptly in most cases as with any of the supposed specifics. Expectant treatment, supplemented by symptomatic treatment, has proved in many institutions to give excellent results without the necessity of troubling the patients with more or less dubious drugs. It was important that the patient should be given certain medicine and impressed with the idea that this medicine was expected to do them good, a suggestion automatically emphasized at every dose, but it is probable that few men of considerable clinical experience now hold the notion that we have any genuinely curative remedy for chorea, though we have certain tonic, alterative remedies which, in conjunction with the setting of the mind at rest, help to put the patient in a condition where the affection is gradually overcome.

The most important object in the treatment of chorea must be its prevention or its early recognition, and its immediate treatment; then there is little likelihood of relapses and, above all, the condition does not last long. Children who have had an attack of acute articular rheumatism or who have suffered from growing pains or any other of the rheumatic simulants of childhood should be watched carefully during their growing period and at certain critical times in early life. They should be especially regarded immediately after being sent to school. The first sign of involuntary twitchings should be taken to mean that the children are overborne and a period of rest from anxiety and study and over-exercise should be afforded them. Of course, all this watchful care must be exercised without attracting the little patient's attention, or the very purpose of the care will be defeated and the mind disturbed.

Rest does not mean that patients should be kept absolutely in bed even after chorea has frankly developed, but that there should be hygienic rest. Long hours of sleep, interesting occupations without much exercise, a period of lying down in the afternoon, but, above all, such occupation of mind with simple pleasant things as keeps their attention from themselves. Visitors should not be allowed to see them; above all, they should not be conscious objects of over-solicitous care on the part of father and mother or the relief of symptoms will be delayed and the condition will be made worse. As a rule, children do not worry about themselves nor their physical ailments, but they can be made to do so by seeing the over-anxiety of others. A good nurse of sympathetic nature with power to interest the child, is better than its mother for a constant companion, though family life, the playing with brothers and sisters and the regular routine of home is the best possible mental solace and occupation. Grandmothers are useful adjuvants in the treatment late in the affection. At the beginning their over-solicitude nearly always does harm.

Habit Following Chorea.—In certain nervous children after the chorea itself has subsided there remains a habit of twitching that often is almost more intractable than the chorea itself. This is particularly likely to be manifest in children who have an unfortunate nervous heredity or in those whose {564} nervous systems have been impaired by preceding infections disease as anterior polio-myelitis, syphilis or one of the forms of meningitis. Occasionally it is seen in children without nervous heredity, but they are usually children surrounded by solicitous relatives, made the centre of pathological interest and constantly fussed about. The habit is not surprising and would remind the observant physician of the whoop that by habit sometimes clings to children in any cough that they may have for months after they have had whooping cough. Often it will be found that these children are capricious eaters, that they take tea and coffee, that their diet instead of being the simple nutritious food that they should have consists of many things that their mothers obtain to tempt their appetites and that the children can really have anything they crave for and get it much oftener than is good for them. To continue any form of presumedly specific treatment in these cases does no good. If arsenic is used over long periods, or any of the salicylates because of the supposed connection of chorea and an underlying rheumatic diathesis they will certainly do harm. The patients' diet can be regulated, nerve stimulants of all kinds must be denied them, and their appetites must be brought into order by the proper care of a nurse who will not yield too readily to their caprices, and then the solicitous environment must be changed. These cases represent a good many of the so-called prolonged choreas and are really habits or tics due to concentration of mind and a certain hysterical tendency to continue to attract attention which may be noted.