THE MODERN HORSE DOCTOR. 187 



LOCKED- JAW. — (Trismus, Tetanus.*) 



Tetanus is a disease of nervous origin, affecting the muscles 

 of external relation, through the agency of perverted nervous 

 force ; it consists in a permanent spasm of some, and in the latter 

 stages all, of the voluntary muscles ; it is subject occasionally to 

 slight remissions, but no relaxation. 



In the human subject, we recognize three peculiar features: — 



1. The body is bent forwards — anticus. 



2. Body bent backwards — posticus. 



3. Body bent siclewise — lateralis. 



The horse, however, is most subject to that form of disease 

 known as trismus, which means painful, fixed, and rigid con- 

 traction of the jaws, mouth firmly closed ; and one or more of 

 the above features are generally blended with trismus. Yet, at 

 the onset, the locked-jaw may be the first symptom that arrests 

 our attention, and so long as this symptom remains unconnected 

 with spasm, or stretching of muscles of the trunk, (it seldom 

 affects those of the limbs,) the case is one of pure trismus — 

 locked-jaw. 



That form of the disorder which is most prevalent in this 

 country is termed traumatic, resulting from wounds — docking, 

 pricking, &c. ; from injury to sensitive tissues ; arising also 



* S. G. "Wilmot, member of the Royal College of Surgeons, who has great 

 experience in the treatment of tetanus, communicates for the Dublin Medical 

 Journal the following : — 



"1. Tetanus depends on irritation, directly or indirectly, of the excito- 

 motory system, or true spinal cord, by which it becomes surcharged with motor 

 influence ; and that inflammation in or about the cord, or any appreciable lesion, 

 is not an essential condition for the development of the disease. 



"2. That our grand object, in the treatment of tetanus, should be to sup- 

 port the patient's strength, by the administration of stimulants and strong 

 nourishment, with a view, as it were, to compensate the vital powers for their 

 great exhaustion, consequent upon the expenditure of force, by the violent 

 muscular contractions, which in some cases are excessive. 



" 3. That, as the removal of the exciting cause — when once the first evidence 

 that irritation has been propagated to the spinal cord becomes manifest — does 

 not in the least degree check the progress of tetanus, or abate the violence of 

 its symptoms, all operations in traumatic cases are generally not only unne- 

 cessary, but in'urious." 



