DISEASES OP ABTICULATI0N3 207 



Mietacarpo-plialangeal articulation, occasionally seen in run- 

 ners. 



In the ox ; sacro-iliac articulation in cows dislocated dur- 

 ing severe labor or by empiric assistance, and hip joint. 



In the dog, hip, elbow, cervical vertebrae, inferior maxilla. 



Name some pathological processes which produce spontaneous 

 luxation ? 



In these dislocations one deals with a joint relaxed by 

 previous disease and thus predisposed to luxations. Such 

 may be a deforming arthritis or a chronic serous arthritis and 

 edema of the retaining ligaments, as a result of which they 

 easily yield to pressure, thus favoring dislocations. 



Describe congenital dislocations. 



In these cases the animal is born with a malformation of 

 a joint, as a result of which the bone cannot retain its normal 

 position. Those dislocations met with in the newly born and 

 occurring during delivery as the result of rough handling do 

 not belong here, but must be classified among traumatic dis- 

 locations. The elbow joint of the dog is subject to congenital 

 luxation. 

 What are the symptoms offered by a dislocation ? 



Generally speaking, they are : Simple dislocation, abnor- 

 mal rigidity in one direction and excessive mobility in another 

 direction. In joints not covered with a heavy layer of muscles 

 there is a visible change in the shape of the articulation. In 

 case the luxation affects an articulation of the leg, the normal 

 position of the bony columns is disturbed, the part may be 

 abnormally extended or flexed, abducted or adducted. The 

 leg appears longer in incomplete luxations, while it appears 

 shorter than normal in complete luxations. In luxations of 

 joiilts of the leg there is severe lameness and pain. 



