280 DISEASES OP CATTLE. 



sharp click, and the animal walks off as if nothing had happened. If 

 the animal resists this method of handling, it may suffice to manipu- 

 late the dislocated kneepan by shoving it inward and forward with 

 the heel of the hand while the affected leg is drawn well forward. 

 Unless some precaution is taken the accident is liable to recur, as the 

 ligaments have been stretched by the dislocation till they no longer 

 hold the bone with that firmness necessary to retain it. The animal 

 should be tied and the foot fastened forward, so that the patient can 

 just stand on it comfortably, by means of a rope or strap around the 

 fetlock carried forward between the front legs around the neck and 

 tied on the breast. 



Should this accident occur more than once it is a good practice to 

 apply a blister around the joint, as in the formula recommended for 

 sprain of shoulder, and observe the precautions as to restraint and subse- 

 quent treatment there recommended. With this one exception, disloca- 

 tions in the ox occurring independently of other complications are rare. 



Dislocation with fracture may occur in any of the joints, and where 

 one is suspected or discovered, examination should always be made 

 for the other before treatment is applied. When a fracture occurs in 

 the vicinity of a joint the force sufficient to rend the bone is likely to be 

 partly exerted on the immediate tissues, and when the bone gives way 

 the structures of the joints are likely to be seriously injured. It occa- 

 sionally happens that the injury to the joint becomes the most impor- 

 tant complication in the treatment of a fracture. In order clearly to 

 understand the reason for this a few words are necessary in relation 

 to the structure of joints. 



The different pieces constituting the skeleton of the animal body 

 are united in such a manner as to admit of more or less motion one 

 upon another. In some of the more simple joints the bones fitting 

 one into another are held together by the dense structures around 

 them, admitting of very little or no movement at all, as the bones of 

 the head. In other joints the bones are bound together by dense car- 

 tilaginous structures, admitting of only limited motion, such as the 

 union of the small bones at the back part of the knee and hock 

 (metacarpal and metatarsal). In the more perfect form of joint the 

 power of motion becomes complete and the structures are more com- 

 plex. The substance of the bone on its articular surface is not cov- 

 ered with periosteum, but is sheathed in a dense, thin layer of carti- 

 lage, shaped to fit the other surfaces with which it comes in contact 

 (articular). This layer is thickest toward its center when covering 

 bony eminences, and is elastic, of a pearly whiteness, and resisting, 

 though soft enough to be easily cut. The bones forming an articula- 

 tion are bound together by numerous ligaments attached to bony 

 prominences. The whole joint is sealed in by a band or ribbon-like 

 ligament (capsular ligament) extending around the joint and attached 

 at the outer edge of the articular surface, uniting the bones and her- 



