506 VETERINARY SURGICAL OPERATIONS 



but is probably always the result of attempts to gnaw upon 

 bones of large size or to seize large objects. The accident 

 is manifested by the absolute inability to close the mouth by 

 the use of force. The mouth stands open and the watery 

 saliva flows out of each side. The accident in human be- 

 ings is both unilateral and bilateral, and the same is usually 

 said of dogs. The author has never seen the unilateral form 

 in dogs, although its existence is not doubted. 



The displacement is backward ; the condyle slips behind 

 the glenoid, cavity. French describes the accident as a for- 

 ward dislocation, but an examination of canine skulls clearly 

 shows that such an occurrence is a phvsical impossibility. 



.TREATMENT.— The reduction "of this dislocation /is 

 effected by simply depressing the jaw posteriorly but as suf- 

 ficient force is difficult to apply at this point a special ap- 

 pliance must be used. The human surgeon simply depresses 

 the jaws with the thumbs after wrapping them with cloth to 

 provide against a bite as the jaw snaps shut. The length 

 of the jaw of dogs renders this procedure impossible. 



The operator first provides himself with a hardwood stick 

 two and a half feet long, wide enough to ride both posterior 

 molars of the lower jaw and thick enough to assure against 

 bending. After the dog is anaesthetized with ether the stick 

 is passed into the mouth so that its end rests upon the 

 posterior molars, where it is tied firmly to the jaw with wrap 

 after wrap of good strong tape or cord. The assistant now 

 supports the head with both hands and the operator takes 

 hold of the outer end of the stick with the left hand and the 

 part bound to the jaw with the right. By pressing down- 

 ward with the right (the fulcrum) and upward with the left 

 (the lever) the jaw (the weight) immediately falls into 

 place with the greatest ease. Feeding with easily masticated 

 food is the only after-care required. 



Brachial Paralysis. 



Brachial Paralysis is the name applied to a paralysis of 

 the nerves proceeding from the brachial plexus due to a di- 

 rect injury to the plexus itself. The injury may be a contu- 

 sion from falling or lying heavily upon the shoulder, from de- 

 cumbency during serious illness or surgical restraint, from 

 traction upon a fixed leg in surgical restraint, or from slip- 

 ping upon the street without falling. The nerves constitu- 

 ting the brachial plexus wind around the upper third of the 

 first rib, and when arranged into a plexus lie between the 



