70 LAMENESS IN THE HORSE. 



there is crepitatiou about the os coronn,, and no fracture of 

 the OS suffraginis present, the diagnosis of " fracture of the 

 OS corona" is in all probability the correct one. 



8. — Fracture of the Os Pedis. 



History. — Same as in Sub. 6, but can also be the 

 consequence of a nail puncture. 



Inspection. — Excessive supportiug-leg lameness, with volar 

 flexion of the phalanges while at rest. 



Palpation. — Crepitation, in the majority of cases, is absent, 

 even on artificial rotation. Compression of the horny box, 

 usually, but not invariably, is painful. Within the first 

 twenty-four hours after the bone has been broken there are 

 no symptoms of acute inflammation of the flexor tendons or 

 hoof, but after that time increased pulsation of the digital 

 arteries sets in. A good deal of discretion therefore is 

 required to diagnose this trouble. If crepitation and marked 

 pain on compressing the hoof are absent, the history of the 

 case, the sudden seveie snpporling-leg lameness, with 

 excessive volar flexion of the phalanges and a careful general 

 examination, to detect another cause, with failure to do so, 

 make the diagnosis of "fracture of the os pedis" tolerably 

 certain. 



9.— Ringbone, 



History. — Severe or slight lameness; when slight, the 

 animal is apt to drive out of it, and the amount of lameness 

 is likely to diminish after prolonged rest. 



Inspection. — More or less severe supporting-leg lameness, 

 increased by short turns or moving the horse in a small 

 circle, especially in the peri-articular form. Lameness is 

 more decided on hard than on soft ground. In stepping, the 



