TREPHINING. 283 



Gangrene and Tetanus have also been recorded as sequelae of 

 this operation. 



The rules we have given apply without change to the amputa- 

 tion of the tan in smaller animals, as sheep, dogs and cats. 



TREPHINING. 



The operation of trephining or trepanning consists in boring 

 into or through a bony or other hard structure, in order to form 

 an aperture for surgical purposes. Although the cranium is 

 usually the seat of the opening, it may be made ia any part of 

 the body where the indications demand it. 



The application of the trephine or of terehration, as it is called 

 when it is performed at the base of the horns of cattle, dates back 

 to antiquity, having a record antedating the time of Hippocrates, 

 and yet it was not until toward the year 1749 that it in fact entered 

 the domain of veterinary surgery. About that time Lafosse, Sr., 

 performed it to oj^en the frontal and maxillary sinuses in the 

 treatment of glanders and other diseases mistaken for it. It was 

 afterwards recommended by Greave and Haubner as the proper 

 treatment for the reHef of purulent collections in the sinuses of 

 the head, and it has been recommended by many others for 

 parasitic affections of the cranial cavity, as cases of coenurus 

 cerebraHs. 



Trephining is undoubtedly indicated in many pathological 

 conditions, and in fact ought to be more frequently practiced 

 by the veterinarian of to-day. Much has been lost, no doubt, by 

 its neglect and disuse. Its value is most fully demonstrated in 

 cases where it becomes necessary to remedy the effects of mechan- 

 ical lesions taking the form of bloody or purulent gatherings 

 within the cranium, like those which may result from the pressure 

 of fragments of fractured bones upon the brain. Fractures of the 

 cranial bones resulting in this manner are not common with our 

 domestic animals, but when they do occur they are always of a 

 serious nature, and too often are beyond remedy. In a case of 

 remediable character the removal of the pressure ujDon the men- 

 inges by trephining and cleansing the wound from the matters 

 which produce and continue it, whether bony fragments or bloody 

 extravasations, is the treatment indicated before any other. Yet 

 as experience has many times jn^oved that the brain is able to sus- 

 tain a very considerable amount of 2:»ressure without betraying 



