PARALYSIS AGITANS.
BY WHARTON SINKLER, M.D.
SYNONYMS.—Parkinson's disease; Shaking palsy; Trembling palsy; Senile chorea; Chorea festinans. The first name is due to the fact that the disease was first fully described by Parkinson in a book published in England in 1817.
Paralysis agitans is a neurosis, chronic in its forms and characterized by a tremor which gradually increases in extent and severity. The tremor is not increased by voluntary muscular movements. A peculiar manner of walking, known as festination, comes on later in the disease, and there are also alterations in the attitude of the head and trunk.
It is a disease which belongs to middle age, being rarely seen before forty years, although cases are quoted by Charcot as early as twelve and sixteen years. Constant and prolonged exposure to dampness and cold seems to bring on the disease, and it is sometimes caused by sudden emotion, like fear or distress. The following case is an instance of the latter:
Case I.—Mr. A. M——, æt. fifty-two years, consulted me Oct. 1, 1883. He is a bookbinder by occupation. His habits have been good. He had a chancre in 1861, but had no secondary troubles. He was in the army from 1861 until 1866. In 1866 he went into business for himself, and, although his business was large, he had no great anxiety or worry. His general health has been good, and he has had no illness except an attack of malarial fever about six years ago. In May, 1883, he was standing by an elevator door on the fourth floor of his place of business, and, seeing that the elevator was caught by something, released it. It immediately fell with a crash to the second floor, and as there were two or three persons on it, Mr. M—— thought they must have been killed or severely injured. He was greatly excited and alarmed, and soon after he had assured himself that none of the occupants of the elevator had been hurt, discovered a trembling of the right hand. The tremor has continued ever since, and has extended to the arm and leg.
On examination there is seen a coarse tremor of the right arm and leg while the limbs are at rest. A voluntary muscular movement stops the tremor, and it also ceases during sleep. When he makes an effort with the right hand, as, for instance, in squeezing the dynamometer, the tremor ceases in the arm, but becomes greatly exaggerated in the right leg. While occupied in doing anything he does not notice the tremor, and it stops when he is lying down.
The dynamometer shows, right hand 150°, left hand 120°. After two years have elapsed the disease has gradually progressed in severity.