1020 DISEASES OF THE HOCK. 



cases have been reported of this method being successfully employed. 

 It appears by no means impracticable. In men, hygroma has for a 

 long time been treated on the same principle. 



Wounds of the point of the hock may here receive consideration, 

 as t hey are often of importance in the treatment of capped hock. 

 Infectious processes in the skin and subcutaneous bursa almost always 

 take a favourable course, and, though liable to be followed by some 

 thickening, do not cause further trouble, even when the swelling is 

 of considerable size. The same is true of wounds. It is quite other- 

 wise in injuries of the serous bursa or the tendon of the flexor pedis 

 perforatus, and suppuration or septic infection at this point is highly 

 dangerous. Marked pain soon sets in, causing the leg to be con- 

 tinuously rested, and movement, as far as possible, avoided. The 

 swelling extends above the hock towards the tibia, fever sets in, 

 laminitis may attack the other foot, in consequence of the continued 

 weight on it, and the animal prove unable to stand. It then lies 

 continuously, and, if not destroyed, may die from the effects 

 (decubitus). 



Post-mortem examination shows the cartilaginous covering of 

 the tuber calcanei to be partly or entirely eroded and the flexor pedis 

 perforatus cap more or less abraded. The severe pain and dangerous 

 character of the disease are essentially due to movement of the tendon 

 over the surface of the tuber calcanei, now denuded of cartilage. 



Any injury of the perforatus tendon, or even of its bursa, may 

 provoke such results, and it is therefore scarcely needful to say that 

 in recent wounds every effort must be made to prevent infection. 



IX.— LUXATION OF THE FLEXOR PEDIS PERFORATUS TENDON. 



The flexor pedis perforatus tendon, at the spot where it plays 

 over the point of the hock, is expanded into a kind of cap. A short 

 but powerful prolongation of the tendon is inserted into the os calcis 

 on either side, just in front of the point of insertion of the tendo 

 Achillis, which prevents the tendon slipping off the summit of the os 

 calcis. Sometimes one of these ligaments is ruptured, allowing the 

 tendon to glide off the calcis towards the opposite side, and to lie 

 towards the lateral surface of the hock. Gunther describes a case of 

 dislocation towards the inner side ; others have seen it occur out- 

 wardly. The direction depends, of course, on which attachment is 

 ruptured. As the tendon passes over the hock from within outwards, 

 one would expect that the external attachment would most frequently 

 suffer, and that dislocation would be towards the inner side. On 



