224 DISEASES OF THE JOINTS. 



of lymph ; coagulates upon the lips of the wound, and oozing 

 through this there will be a thin watery discharge. There is 

 exudation of a large quantity of lymph into the tissues surround- 

 ing the joint, which becomes partly organized, forming a hard, 

 firm swellinfT. The secretion from the wound is now unhealthy, 

 purulent, or tinged with blood, whilst abscesses begin to form 

 around the articulation. 



The fever and debility increase from day to day if the local 

 symptoms be not arrested ; and finally the animal dies from the 

 irritation. 



Condition of the Part. — From the admission of air into the 

 synovial cavity, inflammation of the synovial membrane is 

 excited ; this extends into the extremities of the bones con- 

 stituting the articulation; their cancelli become turgid, the 

 Haversian canals enlarged ; the tissues contained within them 

 form a disorganized mass, infiltrated with ichor ; absorption of 

 the termination of the vascular part of the bone immediately 

 contiguous to the non- vascular laminal layer ensues, by which 

 it is detached (along with the cartilage covering it) from the 

 extremity of the bone, and may be found floating in thin 

 masses in the synovia within the joint. This process goes on 

 simultaneously at the extremities of both the bones of the 

 articulation, thus exposing their vascular interiors, from which 

 loops or spongy granulations spring up luxuriantly. These 

 unite with each other, and form vascular communications from 

 the cancellated structure of one bone to that of the other, this 

 being the first step in the process of internal anchylosis. From 

 the blood-vessels of these new formations an exudate is formed, 

 which is finally converted into bony matter. 



These granulations easily bleed, and when blood is seen in 

 the synovial discharge, the veterinarian will understand that the 

 laminal extremities of the bones have been removed, that their 

 vascular interior is exposed, and that, if the joint affected be one 

 of extensive motion, it will be useless to keep the animal longer 

 in its misery. 



Treatment. — The treatment of open joint, to be successful, 

 must have two objects in view : — 1st. To promote the healing 

 of the wound by the first intention, or by the adhesive pro- 

 cess. 2d. To prevent inflammation. For these purposes, both 

 local and general measures are required, the local being the 



