122 LAMENESS OF THE HORSE 



it occupies a position on the dorsal (anterior) part of the articu- 

 lation and extends around the sides of the joint. 



Periarticular ringbone is characterized hy exostoses which 

 are situated on the sides of the phalanges and not extending 

 around to the anterior part of the joint. This type of ringbone 

 as well as the articular may occur "high" or "low." 



Fig-. 19 — Phalangeal exostoses in chronic ringbone. Museum specimen of 

 the Kansas City Veterinary College. 



With the trau malic form of ringbone, all consequences, as to 

 the size and form the exostosis is to assume, depend upon the 

 nature and extent of the injury. 



Rachitic ringbone is frequently observed in some sections of 

 tlie country and docs not oi-diiiarily cause much if any lameness. 

 It is a disease of colts and may affect one or all of the phalanges 

 at the same time. As the sul)jcct advances in age there is more 

 or less diminution in the size of the enlargements. 



