DISEASES OF BONES. 293 



582. Anclujlosis or Stiff Joint. 



Anchylosis, or stiff joint, is a result of previous disease, rather than a 

 disease in itself. It is occasioned by the presence of deposits, which have 

 resulted from previous inflammation in the structure of, or in the neigh- 

 bourhood of the joint. It consists in more or less complete consolidation 

 of the parts within or around the articulation. 



Anchylosis may arise from thickening and induration of the fibrous 

 capsule, or from the formation of fibroid bands within the joint ; or it 

 may be caused by partial or complete erosion of the cartilages and 

 synovial membranes, the material exuded from the bones becoming 

 organised into osseous matter, and firmly cementing the bones of the 

 joint together. This is called true anchylosis. Or it may arise from 

 shortening, contraction, or wasting away of the muscles, which in health 

 would move the joint. 



Inflammation in a joint, or even in the neighbourhood of a joint, is 

 always a source of some danger. There is always some reason to fear, 

 lest the deposit resulting from the inflammation should interfere with the 

 free motion of the part, even if it does not produce partial or conqilete 

 anchylosis. 



583. Treatment. 



For confirmed Anchylosis, arising from permanent alterations, there is 

 no remedy. The previous disease, whatever it may have been, has caused 

 the mischief, and anchylosis is the result. The process of anchylosis may 

 in some cases be hastened by the application of the actujil cautery. This 

 is occasionally advisable in the treatment of diseased joints. 



For mere stiffness (as distinguished from anchylosis), arising from 

 recent thickenings or dei)osits in or about the neighbourhood of the joint, 

 the treatment consists in rest ; and in the application, as soon as the 

 active inflammation has left the part, of absorbents, such as iodine, or 

 biniodide of mercury. Though we cannot be certain of a favourable 

 result, yet there is reason to hope, that by the use of such means, so 

 much of the thickening or exostosis may be removed, as will at least pre- 

 vent its interfering with the motion of the joint. With the removal of 

 such interference, the pain and irritation will cease. 



In human surgery, oi)erations are sometimes undertaken for the re- 

 moval of such deposits ; but in the horse they do not answer, because 

 there are no means of placing him in such a position as will take the 

 weight off the limb for a sufficient length of time after the operation. 



