353 



SUNDRY ADDITIONAL AFFECTIONS OF THE EXTREMITIES. 



Among these there are tliiee wliich will principally occui)y our 

 attention, and these may be considered as forming a single group. 

 In some parts of the legs may be found certain peculiar little struc- 

 tures, of a sac-like formation, containing an oily substance designed 

 for the lubrication of the parts uj)on which they are placed for the 

 purpose of facilitating the movements of the tendons which pass over 

 them. These little sacs or muco synovial capsules are liable under 

 peculiar conditions of traumatism to become subject to a diseased 

 process, which consists principally in a hyper-secretion of their con- 

 tents and an increase in dimensions, and the}'^ may undergo peculiar 

 pathological changes of a character to disable an animal, and in many 

 instances to cause serious blemishes which can not but depreciate his 

 value. These growths, which are known as hygromata, may result 

 from external violence, as blows or bruises, and may appear in the 

 form of small, soft tumors, painless and not inflammatorj- in charac- 

 ter, but, by a repetition of the cause or renewal of violence, likely to 

 acquire a new severity. Severe inflammation may supervene, with 

 suppuration, which, filling up the cavity, the walls will become thick- 

 ened and hai'd, and the formation of a tumor follow, which, resisting 

 all forms of treatment, can only be made to disappear by subjecting 

 tliem to the edge of the bistour3^ 



The elbow, the knee, and the hock are the principal i3arts of the 

 body where these lesions are ordinarily found, and on account of their 

 peculiar shape and the position they occupy they have received the 

 denomination of being capped. We shall consider them in their 

 peculiar aspect. 



Capped elboiv. — The shoe boil, commonly so called, is almost too 

 well known to require a definition from us. An enlargement at the 

 point of the elbow is the lesion, so called, which is simi)ly the result 

 of pressure of the heels of the shoe upon that part. There are, of 

 course, some conditions necessary for the development of the shoe 

 boil, and for the pressure of the heels uj)ou the spot where it occurs. 

 Excessive length in the shoe and a formation of the animal with a 

 cannon bone so long that the flexure of the knee brings the heel in 

 contact with the elbow may be termed the predisposing causes, but 

 to these must be added another necessary condition in the peculiar 

 mode of resting adopted by the affected animal, as exhibited in his 

 manner of lying down, which is that of the cow, b}^ resting upon the 

 breastbone with the legs flexed under the body — a most eligible and 

 natural posture for effecting the result which follows. 



The heel just pressing against the elbow, the hard iron of the shoe 

 in contact with the soft skin, with the weight of the body added, 

 forms a combination of causes which can not well fail to produce the 

 59(31— HOR 12 



