504 VETERINARY SURGICAL OPERATIONS 



The coxo-femoral articulation, in exceptionally rare cases, 

 is dislocated in dogs and oxen; the scapulo-humeral in still 

 more exceptional instances may be dislocated in horses ; and 

 partial dislocation of the cervical vertebra have been re- 

 ported. But these occurrences are too rare to warrant any 

 special attention. The more common ones, and these are in- 

 deed rare enough, are.: — (i) Dislocation of the fetlock of 

 horses: (2) Dislocation of the patella from the femoral 

 trochlea in horses; and (3) Dislocation of the temporo-max- 

 illary articulation in dogs. 



1. Dislocation of the Fetlock of Horses. This accident 

 occurs to work horses, and is caused by catching the shoe 

 calk or the foot in a defective pavement, street-car rail, 

 bridge, etc., while walking fast enough to be thrown vio- 

 lently to the ground in a forward and lateral direction. The 

 foot is fixed and as the body topples from its momentum the 

 extremity is broken at a right angle at the fetlock. When re- 

 leased the phalanges dangle. There is no displacement re- 

 quiring forcible reposition; the joint falls into place auto- 

 matically, although it can be worked laterally like a hinge. 



The injury is serious in that' the lateral ligament and the 

 capsule are lacerated and the surrounding soft tissues are 

 more or less bruised from the tension to which they were 

 subjected. 



TREATMENT. — The patient is placed in the slings and 

 the leg bandaged in the manner recommended for fractures 

 of the phalanges (page 497) after the swelling has reached its 

 climax. During the first three days a good, firm and thick 

 muslin wrap is depended upon as a retaining bandage. The 

 permanent bandage of electrician's tape is removed and 

 readjusted after ten days to fit the decreasing size of the 

 leg, incident to the disappearance of the swelling. In four 

 weeks it can be safely dispensed with and substituted by an 

 ordinary muslin support. At the end of six weeks firing 

 and blistering is indicated to assist in curing the lameness 

 that usually sojourns stubbornly. A protracted rest at pas- 

 ture is helpful, but in almost every instance the joint is per- 

 manently enlarged, and not infrequently the lameness is 

 chronic. 



2. Traumatic Dislocation of the Patella from the 

 Trochlea must not be confounded with simple "pseudo-luxa- 

 tion of the patella" (stifle-cramp). This is both a rare,and a 

 serious injury. It usually occurs in some mysterious manner 

 by stall maneuvers at night, and is manifested at once by in- 

 ability to reach the floor with the foot of the affected leg. 



