Tetanies. 305 



in the early stages of tetanus. The spasms of strychnia are 

 general, while those of tetanus are often most intense in particular 

 groups of muscles often at first in the vicinity of the inoculation 

 wound. 



From rabies, tetanus is easily distinguished by the absence of 

 any history of a bite ; by the persistence of the tonic spasms 

 especially of the masseters and abdominal muscles during the 

 intervals between the more violent paroxysms (in rabies there is 

 temporary complete relaxation) ; by the absence of clonic spasms 

 which alone occur in rabies ; by the absence of the paralysis 

 which characterizes advanced rabies ; by the mental clearness 

 and the absence of hallucinations or mischievous disposition which 

 are marked features of rabies ; by the absence of the depraved 

 appetite of rabies ; and by the fact that the brain does not contain 

 the infecting germ as is the case in rabies. 



From rheumatism of the neck (torticollis) tetanus is easily dis- 

 tinguished by the permanent trismus which is not shown in rheu- 

 matism, and by the fact that spasms are easily roused by any 

 artificial excitement, indicating an extraordinary hypersesthesia 

 and excitability which are nearly absent in rheumatism. The 

 steady unmistakable progress of tetanus is in itself diagnostic. 



From meningitis tetanus is to be diagnosed by the presence of 

 trismus without impairment of the mental faculties or fever. In 

 meningitis the spasms are usually confined to particular groups of 

 muscles and do not become generalized under active excitement as 

 in tetanus. Even if the spasms of meningitis affect the jaws and 

 pharynx they are rarely paroxysmal or roused by excitement as 

 in tetanus. They may even be clonic. 



Tetany is more commonly localized in particular groups of 

 muscles, and shows longer and more irregular intervals between 

 paroxysms than does tetanus. It is improved by thyroid extract, 

 and may be roused at will to contraction by pressing on the nerve 

 going to the affected muscles. 



Laminitis in its most violent form and early stages, may be 

 confounded at first glance with tetanus, but the high fever, the 

 standing on the heels, the advance of the hind legs under the 

 body, the great heat and tenderness of the feet, the impossibility 

 of standing on one fore foot when the other is lifted and the 

 strong pulsation of the digital arteries, are sufficiently distinctive. 

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