178 



Common Diseases of the Horse 



It occurs more frequently in the fore limb than the hind, and is 

 usually more serious in its nature there. 



The conformation of the pastern is a great predisposing cause 

 of the disease. A short pastern favours its production by allowing 

 undue weight to be placed upon the terminal bones of the leg; 

 and a too long pastern is also found to be a favourable site. In a 

 short -pasterned horse ringbone usually occurs in the fore limb; 

 m the long-pasterned animal it usually affects the hind. 



Symptoms. — The deposit of bone may be either large or small; 

 it may extend completely round the pastern — hence the term ring- 

 bone — and cause great disfiguration of the limb, 

 being evident to even the most casual observer; or 

 it may be of a very slight nature, and not easy to 

 detect even by the expert. 



Lameness is caused sooner or later. The de- 

 gree of lameness, however, does not depend upon 

 the size of the growth, but upon its position and 

 the parts affected. The deposits of bone that 

 cause lameness must interfere with the articula- 

 tion of a joint by either interfering with its action 

 mechanically and thus stiffening it, or else by 

 causing an inflammation of the inside of the joint 

 on either end of the bones. The latter condition 

 is, of course, a most serious and almost incurable 

 disease, which causes the animal to suffer great 

 pain. On the other hand, the ringbone which 

 causes lameness by uniting the bones together, and 

 thus stiffening the limb, is not a painful disease, 

 and only interferes with the mechanical action of 

 the limb. This state of affairs is, of course, the ter- 

 mination of the disease, and it may have been painful during its 

 production. A simple deposit of bone that is not connected in any 

 way with the joint is practically only a disfiguration, and the term 

 "ankle bone" is often applied to this condition. It is advisable, 

 however, to regard it with a considerable amount of suspicion, and 

 when occurring in a horse with badly-formed pasterns, one never 

 knows how soon other deposits will appear which will ultimately 

 involve the joint. 



Ringbone may occur on any part of the pastern ; it may be 

 in front or behind, or on either side, that on the side being usually 

 of a less-serious nature. 



Low ringbone, or that affecting the bones that are contained 

 in the hoof (it is also known as pyramidal disease), is the most 



"High" 

 Ringbone 



