82 LAMENESS OP THE HORSE 



ference of temperature between the normal areas and the cool 

 anemic parts. When the subject is allowed to rest, circulation 

 is not taxed, and there is a return to the original and apparently 

 normal condition, only to recur again with exertion. This con- 

 dition characterizes thrombosis. 



Treatment. — In these cases, little if any good directly results 

 from any sort of treatment in the way of medication. Abso- 

 lute rest is thought to be helpful. Potassium iodid, alkaline 

 agents such as ammonium carbonate and potassium carbonate, 

 have been administered. Circulatory stimulants also have been 

 given, but it is doubtful if any good has come from medication. 



Fracture of Humerus. 



The shaft of the humerus, protected as it is by heavy muscles, 

 is not frequently fractured; and fractures of its less protected 

 parts, as for example, the head, are complicated in such manner 

 that resultant arthritis soon constitutes the more serious condi- 

 tion. 



As a result of falls on frozen ground, kicks or any other form 

 of heavy contusion, the humerus is occasionally broken. It is 

 rarely fractured otherwise. Because of the force of contusions 

 usually required to effect humeral fracture, the manner in which 

 the bone is broken, with respect to direction, is variable. Often 

 oblique fractures exist and occasionally there occurs multiple 

 fracture. In addition to the ordinarily serious nature of the 

 fracture itself, there is always much injury done the adjoining 

 structures. 



Sjrmptomatology. — Mixed lameness and manifestation of 

 severe pain characterize this affection. Considerable swelling 

 which increases, in some cases for a week or more, is to be ob- 

 served. Crepitation is readily detected, if pain and swelling is 

 not too great to prevent passive movement of the member. 

 Where intense pain is not manifested, because of manipulation, 

 one may abduct the extremity and thereby occasion distinct 

 crepitation; but when it is po-ssible to recognize crepitation by 

 liolding the hand in contact with the olecranon while tlie animal 

 is made to walk, this method is to be preferred, if the su])ject 



