468 jPRtNCIPl.ES OF VETERINARY SURGERV 



The attitude of the animal varies with the severity of 

 the contractiotts. It is according to the attitude that the 

 varieties of the disease hav^e been estabhshed. If the Con- 

 tractions are in opposite groups of muscles, the patient is 

 rigid; the head, neck and trunk are on a horizontal line; 

 this is orthotonOs. Generally the head is elevated and thrown 

 backward, the dorso-lumbar column is concave and the tail 

 is raised: this is episthotonos, the most frequent attitude. It 

 occurs in various degrees of severity, and may be limited 

 to the cervical or to the dorsal region. 



ANNOTATION. 



There is no good argument in favor of preserving the words ''enipros- 

 thotonos" and "pleurosthotonos" in the nomenclature of tetanic attitudes of 

 veterinary patients. These conditions are remarkable chiefly for their scarcity 

 in the tetanus of domestic animals. The fact is, they never occur, in infec- 

 tious animal tetanus. Lateral and inferior incurvations are quite impossible 

 from generalized muscular contractions such as occur from the poison of 

 Nicolaier's bacillus. When the typical attitude of any given infection mani- 

 fests itself the contractions are already well distributed over the entire mus- 

 cular system. Although some particular part of the muscles may be more 

 rigid than others, it cannot be disputed that in animals tetanus is always pretty 

 well generalized in the strictest sense of the term. This being the case, 

 opisthotonos is the only tetanus possible. The attitude is due to the great 

 strength of the dorsal muscles as compared wilh the ventral ones. The jaw 

 i.s locked shut because the muscles that control the mouth are much more 

 forcible than their opponents, the head is extended because of the greater 

 power of the superior cervical muscles, and the spinal column is depressed 

 because of the enormous size of the longissimus dorsi and its assistants. 

 The hind legs are drawn backward owing to the strength of the gluteal 

 group, and outward on account of that of the abductor muscles of the thigh, 

 as compared with that of the muscles that draw the limb toward the medium 

 line. 



Furthermore, impressions that tetanic contractions vary in strict obedi- 

 ence to the location of the initial trauma, cannot be strengthened by obser- 

 vation. That the point of infection has any influence whatever on the degree 

 of contraction in any part of the body would not be seriously entertained by 

 any experienced veterinarian. The tetanus cases following nail punctures in 

 the hind feet, for example, are not uniformly severe in the posterior groups 

 of muscles. Neither can it be claimed that these muscles are always the 

 first to become contracted when the "entrance point" has been the hind foot. 

 Tetanic contractions are not always uniformly severe over the whqle body, 

 however. A slight trismus may accompany severe contraction of the pos- 

 terior groups and vice versa, but the diflference is seldom traceable to the lo- 

 cation of the trauma. — L. A. M. 



