792 Catalepsy. St. Yitus's Dance. 



word, ])iit it appears suitable to designate them as "cataleptic stififening 

 of the limbs." 



The attack occurs either only once or it is repeated, the animal sud- 

 denly stifiPening in the position and attitude which it assumed imme- 

 diately previously in walking or lying, and thereafter is unable to 

 execute any further movement. The muscles feel tense and firm, their 

 outlines are sharply defined, there is increased resistance to passive 

 movement, but the extremities, head or neck may be put in another 

 position without any great effort, and they will remain in these posi- 

 tions even if the equilibrium of the body is thereby endangered ; one 

 receives the impression of the moving of a plastic flexible mass (waxy 

 flexibility, flexibilitas cerea). 



Treatment depends upon the cause of the illness. 



Literature. Frohner, D. Z. f. Tm., 1883, IX, 119. 



7. St. Vitus 's Dance. Chorea. 



{Sydenham,' s Chorea; Chorea minor, s. Scfi Vifi.) 



As St. Vitus 's dance is designated a neurosis which is mostly transi- 

 tory and occurs chiefly in childhood, being characterized by involuntary 

 and arhythmic but irregularly distributed twitchings of muscles of 

 manifold combinations, fretiuently connected with psychic disturbances. 

 The abnormal movements are in themselves coordinated combination 

 movements (grasping, defensive, or movements of expression), yet at the 

 moment of their occurrence they are alwaj^s without purpose, and suffi- 

 cient to disturb other intended movements. During sleep the convulsions 

 usually disappear entirely. 



A more or less similar clinical picture is said also to occur in animals, 

 yet in most cases organic diseases of the nervous system or of other 

 organs of the body must be assumed as fundamental affections, and there- 

 fore they must not be classed with St. Vitus 's dance proper. Thus in 

 the course of distemper or after the cessation* of the acute symptoms of 

 the disease, which sometimes are not noticed at all, local spasms may 

 occur, which by French authors and recently also by Joest have been 

 designated chorea, but not justly so, and still less as a distinct disease as 

 Joest has proposed. Clinically there is a great difference between chorea 

 and the spasms in distemper. In distemper the twitchings are continued in 

 the same group of muscles or limited to the region of certain nerves in 

 which they originate ; they exhibit a more or less decided rhythmic char- 

 acter and are continued and lasting. The peculiarity of distemper spasms 

 has been sho"\Aai by repeated microscopic examinations to be due to dissem- 

 inated myelitis or encephalitis, that is an organic disease of the nerves. 

 Dexler had already explained spasms of distemper in this manner, and 

 recently this author has shown by myographic sketches that the muscle 

 convulsions are similar to those seen in the socalled "tic," which disappear 

 with consciousness, and are influenced by conditions which cause psychic 

 disturbance. 



Sometimes spasms are due to severe intestinal catarrh or inflamma- 

 tion, and occasionally to other diseases (in the case of Lienaux an ab- 

 scess in the neck) which spasms, however, cannot either ])e classed vnth 



