PARALYSIS, 399» 
region have disappeared, the atrophy of muscles is rapid, there is diminu-- 
tion of the electric excitability and reaction of degeneration partial or- 
complete in the paralyzed structures. 
Paralysis of peripheric nervous origin—the ones that we have particularly~ 
in view—are generally limited to a single nerve or to a group of nerves in 
the neighborhood, and rarely do they involve a great number of muscles.. 
At the same time that the paralysis of motion, anesthesia and trophical. 
disturbances are observed, ordinarily precocious, which little by little be- 
come more marked, reflex excitability is destroyed. Electric explora-. 
tion is not slow in giving the reaction of degeneration.’ 
To establish a rational treatment of akinesia, the nature of the lesion. 
and cause of it must be known. Ischemia and congestion, hemorrhage, 
softening, acute or chronic inflammation, tumors, various infections or: 
intoxications, are as many morbid processes liable to act on the nervous. 
system and promote paralysis very variable in their seat and in their march. 
Paralysis occurring rapidly are due to mechanical, toxic or infectious. 
causes, according to the cases: nervous compression, cerebral or medul- 
lary hemorrhage, intoxication by vegetal or mineral poisons, infection and 
intoxications by microbian poisons. faralysis progressing slowly announce* 
a chronic inflammation or a neoplasm. 
In the chapter Diseases of the Brain and Cord we will come back on 
the paralysis of cerebral and those of spinal origin. Several local paralysis: 
will be studied with other affections of the regions where they are met, 
We will here consider specially the akznesia of extremities. 
From what has been said above it is seen that oca/ paralysis are ordinarily 
determined ‘by various causes which abolish the functions of a nerve by~ 
destroying its continuity or altering its structure: by section, com- 
pression, distension, laceration of the nervous branches, neuritis and. 
neuromas. It is sometimes difficult to learn their precise nature. Some 
are of infectious or toxic origin. Often paralysis of unknown origin are 
attributed to rhexmatism, when most commonly they are the result of a. 
slip, a fall or perhaps of an infection or intoxication ; we hold that 
truly rheumatismal paralysis or 2 /rigore are very rare in all animals. Some: 
are peculiar to some species; we meet with diphteritic paralysis only in 
aviary species. 
According to their origin and the importance of the organs affected, 
1 The reaction called degeneration is partial or complete. Specially accused ir. 
traumatic paralysis consecutive to the section of a nerve, it has for principal characters ¢ 
diminution or loss of the excitability of the nervous trunk by faradic and galvanic cur-- 
rents; the persistency or even the exaltation of the galvanic contractility of muscles, im. 
contrast with the diminution or abolition of the faradic contractility; the slowness of: 
the muscular jerking. 
