570 DISEASES OF THE HEAD, NECK. VEINS, ETC, 



FISTULOUS WITHERS 



Fistulous withers resembles poll-evil in all particulars except 

 its seat. It is caused by bruises from ill-fitting saddles ; but 

 some horses, from the conformation of the withers, are more 

 prone to be thus injured thair otliers. Horses with high withers 

 are particularly liable to the injury. Sometimes the spines of 

 the dorsal vertebrae become affected with chronic inflammation 

 from repeated bruisings ; their extremities spread out, or some 

 portions of them become necrosed. These are complicationf, 

 which must be provided for in the treatment, which is to hie 

 conducted upon the same principles as that for poll-evil, namely, 

 to make a depending orifice for the discharge of purulent matter, 

 either by seton, incision, or by a counter-opening made at a point 

 below the bottom of the sinus. 



INFLAMMATION OF THE JUGULAK VEIN. 



Inflammation of the jugular vein occurs as a sequel to bleeding 

 (phlebotomy), and is due to a constitutional predisposition to 

 local inflammation — as in that condition co-existent with acuta 

 laminitis — accidental disturbance of the wound after the opera- 

 tion, or to carelessness on the part of the operator. 



In order to secure the healing of the puncture made by tlift 

 lancet or fleam, by immediate union, it is necessary to bring the 

 lips of the wdimd immediately and closely together. The blood, 

 if any, on its surface is thus pressed out, and the divided blood- 

 vessels and nerves are brought into perfect contact. Union 

 may thus be effected in a few hours. If this method of union 

 is not secured, the wound may heal by the adhesive inflamma- 

 tion ; but if suppuration occur, the inflammation will in aU 

 probability extend to the coats of the vein. 



The more immediate causes of phlebitis are said to bo, using 

 a rusty fleam, bungling in performing the operation, or from the 

 animal rubbing the pin against the stall or manger. 



Patliolocjij. — Inflammation of a vein is characterised by a 

 i-eddening of all its coats, owing to congestion of ita x'asa 

 vasoi'um ; an exudation is poured out from the coats of the 

 vein, wliich, along with its contents, forms a solid coagulum, 

 The experiments of Geudiiu go to prove that the clot is not. 



