314 VETERINARY SURGICAL OPERATIONS 



the spinous processes are generally more or less affected. 

 These may need attention cr not, according to the amount 

 of disease found. Ordinarily a little curettage is sufficient. 

 Extensive resection of the spines is very seldom ever indi- 

 cated, and is always a dangerous procedure, in that fatalities 

 often follow and healing is more retarded than encouraged 

 thereby. Exfoliated parts must, of course, be removed and 

 the underlying roughness smoothed up with the curette, but 

 the sawing off of large parts of the spines still nourished 

 with circulation, is not recommended. 



To control bfeeding, which is always copious, the author 

 uses hot iron cauterization along the walls of the incision 

 before the resection proper begins. 



Third Step. — The Drainage.— The direction and the 

 course of the various tracts are now traced out from the 

 wound to their very depths. For this purpose probes and 

 sounds which can be bent at will may be required when the 

 tracts are deep ; in other instances the fingers may be long 

 enough to find the bottom. The aims here are to leave no 

 tract or sinus undiscovered, to find the most dependent part 

 of each, and to drain each to the surface of the body, if 

 possible at points where gravity will carry off the discharges. 

 This latter aim is often more easily said than done, owing 

 to the thickness an'd the disposition of the region through 

 which the openings must be made. The tracts may lead be- 

 neath the voluminous superior cervical muscles just above 

 the last cervical vertebra, downward along the long spinous 

 processes of the dorsal vertebras to the articulation of the 

 ribs, or across the spines to the opposite side of the body. 

 Superficial tracts may be found between the outer layers of 

 muscles or just beneath the skin. In rare cases pus has been 

 found to burrow along the dorsal spines and intercostal 

 spaces as far down as the sternum, but the chief point of 

 predilection is the space between the dorsal spines and the 

 cartilage of prolongation, where the sinus is found resting 

 upon the attachment of the serratus magnus, and whence it 

 frequently extends forward as far as the level of the first 

 cervical segment, resting between the lamellar portion of 

 the ligament nuchse and the cervical portion of the same 

 muscle. 



After the causative lesion, — the necrotic ligament and 

 bone, — has been removed, the cure will then depend upon 

 the ingenuity displayed in draining these depths, and main- 

 taining the drainage until cicatrization is complete. If the 

 first part of the operation has been sanguinary to a danger- 



