216 PEINOIPLES OF TETEEINABX SUEGEEY 



becomes limited as the result of chronic inflammation of the 

 flexor pedis perforans and perforatus, the latter being fol- 

 lowed by adhesions and shortening of these tendons. 



W hat is a myogenous contracture ? 



In these, free mobility of the joint is interfered -with by a 

 shortening of muscles. 



Give an example of myogenous contractv/re. 



In the crooked tail as the result of contracture of the lat- 

 eral coccygeal muscles, in the so-called wry neck {caput 

 dbstipum), there exists a contracture of the mastoido humer- 

 alis. In the so-called sprung knee, where a contracture of the 

 external and oblique flexor of the metacarpus is found. 



What are neurogenous contractures ? 



In these the free mobility of the joint is limited, as the 

 result of faulty enervation of certain muscles. 



Give an example of neurogenous contracture. 



This condition is quite often seen in the newly born ani- 

 mal, especially colts, most likely due to a paralytic state of 

 the extensor muscles of the legs, as the result of which the 

 animal knuckles over. 



What is a cicatricial contractu/re ? 



In this form the mobility of the joint is handicapped by 

 the formation of a large amount of scar tissue in close prox- 

 imity to a joint, especially when involving the flexor surface 

 of a joint ; such cicatrices may be due to burns, wounds, and 

 are quite common in our country, especially where barbed 

 wire fences are used, the flexor surface of the hock and 

 fetlock being common sites of such cicatrical contractures. 



