boxes: diseases and accidents. 289 



then drawn away from the body and forcibly pushed forward by 

 an assistant, while another person tightens up the slack in the rope 

 until the affected leg is off the ground in front of the supporting leg. 

 The rope is then drawn taut and the assistant grasps the tail and 

 pulls the cow toward the affected side. The animal makes a lurch 

 to keep from falling, contracts the muscles, and the patella slips 

 into place with a sharp click, and the animal walks off as if nothing 

 had happened. If the animal resists this method of handling, it 

 may suffice to manipulate the dislocated kneepan by shoving it in- 

 ward and forward with the heel of the hand while the affected leg 

 is drawn Avell forward. Unless some precaution is taken the acci- 

 dent is liable to recur, as the ligaments have been stretched by the 

 dislocation till they no longer hold the bone with that firmness neces- 

 sary 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 

 subsequent treatment there reconmiended. With this one exception, 

 dislocations in the ox occurring independently of other complications 

 are rare. 



Dislocation Avith fi-acture may occur in any of the joints, and where 

 one is susjjected 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 

 Avay the structures of the joints are likely to l^e seriously injured. It 

 occasionally happens that the injurj' to the joint becomes the most 

 important 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 sunple 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, admitiing 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 

 ])ower 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- 

 16923°— 12 19 



