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True ring-bone is the term applied to a deposit of bone‘in either of two 
situations. When the deposit of bone involves the pastern joint, that is the 
joint between the two pastern bones, it is termed high ring-bone. This is 
the variety most commonly met with. 
When the deposit affects the coffin-bone joint, that is’the joint between 
the small pastern and the coffin-bone, it is termed low ring-bone, 
Although this latter form is necessarily the more grave variety of 
ring-bone, yet it must be remembered that true ring-bone@in either situation 
always constitutes unsoundness, as it occasions very inveterate and often 
incurable lameness. In some instances, both high and low ring-bone 
coexist at the same time. 
In this figure X shows the position of low ring-bone. 
Speaking of the nature of side-bone, we showed that it is a disease of 
the side cartilages of the coffin-bone ; and it will therefore be?seen that it 
is of-a totally different character from true ring-bone, which fis}a‘fbony 
deposit around the ends of the bones forming the pastern and coffin joint. 
When the deposit involves the latter joint, which our readers will remember 
is within the upper part of the hoof, the lameness is ‘often very severe ; 
because the horn, although elastic, nevertheless, fitting closely, presses upon 
the new growing bone. 
Ring-bones vary greatly in size and shape. They are generally 
confined to the sides and front of the bones ; but sometimes they extend ta 
the back of the joints, forming a complete “ring.” Hence the name has. 
been derived. Sometimes only the sides of the bones are affected, fand. 
sometimes only the front parts of the joints are invaded by the bony growth.. 
When the front part of the bone is affected, the lameness is necessarily very 
severe. Yet it must not be thought that the degree of lameness depends. 
