ANCHYLOSIS 281 



Disease most commonly commences in the synovial membrane, and 

 next in the bones, but seldom in the articular cartilage and connecting 

 ligaments. 



This greater susceptibility to become primarily affected is no doubt due 

 to the greater vascularity of the two tissues referred to, and their higher 

 functional activity. 



Symptoms. — The general symptoms of joint disease are such as result 

 from an attack of inflammation in one or all of the structures entering into 

 the formation of the articulation. 



Lameness is more or less severe, according to the structure involved 

 and the stage of progress of the disease. Swelling of the part, with more 

 or less heat and pain under pressure, will also be observed. 



ANCHYLOSIS 



Anchylosis is that condition of a joint in which the bones forming it are 

 united in such a way as to restrict or altogether prevent their natural 

 movement taking place. The various means by wdiich this is effected has 

 given rise to a division of anchylosis into true and false. True anchy- 

 losis results when, as a consequence of disease, the two ends of the bones 

 within the capsular membrane become united. False anchylosis is induced 

 when inflammatory products surround and enclose the joint, and become 

 callous or ossified, or in other ways fix the ends of the bones and prevent 

 their movement. 



Anchylosis may be complete or incomplete. In the former the union 

 is effected by ossific new growth between or around the ends of the bones 

 forming the joint, and the movement is altogether arrested. In the latter 

 the bones are bound together by fibrous or fibro-cartilaginous tissue, which 

 allows a limited degree of movement to take place in the joint. The 

 uniting medium in this case may sooner or later become converted into 

 bone, by which complete anchylosis is effected. The incomplete form of 

 the disease therefore represents a stage in the development of the complete ; 

 in other words, when the fibrous tissue existing in the one becomes ossified, 

 it is converted into the other. 



Causes. — Anchylosis is the result of inflammation affecting the joint 

 or parts about it. External violence, in the form of blows, wounds, sprains, 

 and other injuries, is the exciting cause. 



In the matter of treatment, but little can be done to render an animal 

 of service for anything ])ut slow work, unless for breeding purposes. 



To break down the morbid development uniting the bones by physical 

 force is a practice sometimes adopted in man, but the ultimate success of 



