jLameness in the eegion of the hock joint. 113 



Palpation. — The swelling about the hock, which in the 

 earlier stages is of a doughy nature, is hot and painful upon 

 pressure. 



Differential Diagnoses. — 1. Subfacial cellulitis. lu cases 

 where wounds penetrate the joint, fever, swelling and 

 abscess-formation follow ; the differentiation between this 

 trouble and inflammation of the hock joint is at times 

 impossible, and some time has to pass before the exact 

 diagnosis can be arrived at. In either affection there is 

 severe mixed lameness, with swelling about the hock and of 

 the regional lymph glands, also deep-seated abscesses. If 

 the opening of the abscess is followed by lessened lameness, 

 it is reasonable to presume that the hock joint is not 

 punctured. 



2. Fracture of the bones of the tarsus. Differentiation 

 is rather difficult unless crepitation is present, which, of 

 course, would point to a fracture. 



3.— Fracture of the Bones of the Hock. 



History. — Severe sudden lameness following slipping, 

 falling, external violence and struggling when cast, with 

 inability to rise. 



FRACTUEE OF THE OS CALCIS. 



Inspection. — Severe supporting-leg lameness, with exces- 

 sive flexion of the hock joint especially, as well as the other 

 joints, and collapse of the entire leg when an attempt is 

 made to sustain weight. In compound fracture the wound 

 and bony splinters may be seen. When the animal walks, 

 the slackness of the tendo-Achilles is readily perceived, 

 while all that portion of the leg below the hock is dragged 

 over the ground. 



