366 CAPPED HOCK. 



the two layers of small bones within the hock the larger wedge -liko 

 bone e, above ; and the middle/, and the smaller one below, and it will be seen 

 that almost the whole of the weight of the horse, communicated by the tibia a, 

 is thrown upon these bones. The cube-bone d does little more than support the 

 point of the hock c. It is then easy to imagine that, in the concussion of hard 

 work or rapid travelling, these bones, or the delicate and sensible membranes 

 in which they are wrapped, may be severely injured. Repeated dissections of 

 horses that have been incurably lame behind, without anything external, during 

 life, to point out the place or cause of lameness, have shown that inflammation 

 of the membranes lining these joints, and secreting the fluid that lubricates them, 

 has taken place. 



Mr. Goodwin narrates a very interesting case in corroboration of this account 

 of hock lameness. The author of this work had the honour of being present when 

 the examination took place. " The patient was a harness horse of unusual perfec- 

 tion, both in shape and action, and was a great favourite with an illustrious per- 

 sonage. He suddenly became lame behind on the off-leg, but without the least 

 accident or alteration of structure to account for it. He was turned out for a short 

 time, and the lameness disappeared. He was then incautiously made to perform 

 his usual work, until perfectly incapacitated for it by returning and aggravated 

 lameness. Suspecting the seat of lameness to be in the hock, although the joint 

 was perfectly unaltered in form, he was, three months after the commencement of 

 the lameness, blistered and fired, and placed either in a loose place or paddock, as 

 circumstances seemed to require. Not the least amendment took place at the 

 end of six months, even in his quiescent state, and, after twelve months 

 from the time of his being given up for treatment, he was destroyed, his case 

 being naturally considered a hopeless one. Ulceration of the synovial membrane 

 was found, taking its origin between the two cuneiform bones. These bones had 

 become carious, and the disease had gradually extended itself to other parts of 

 the joint. Mr. Goodwin had no doubt that if the animal had been suffered 

 to work on for any greater length of time, necrosis, or anchylosis of every bone 

 concerned in the hock, would have been the result." (Veterinarian, iii. 158.) 



Much more depends, than they who are not well accustomed to horses 

 imagine, on the length of the os calcis, or projection of the hock. In propor- 

 tion to the length of this bone will two purposes be effected. The line of 

 direction will be more advantageous, for it will be nearer to a perpendicular, 

 and the arm of the lever to which the power is applied will be lengthened, and 

 thus mechanical advantage will be gained to an almost incredible extent. The 

 slightest lengthening of the point of the hock will wonderfully tell in the course 

 of a day's work, and therefore it is that the character of the os calcis is of such 

 immense importance. 



The point of the hock is sometimes swelled. A soft fluctuating tumour 

 appears on it. This is an enlargement of one of the mucous bags of which 

 mention has been made, and that surrounds the insertion of the tendons into 

 the point of the hock. It is termed, 



CAPPED HOCK. 



It is seldom accompanied by lameness, and yet it is a somewhat serious busi- 

 ness, for it is usually produced by blows and mostly by the injuries which the 

 horse inflicts upon himself in the act of kicking : therefore it is that a horse with 



* These opinions of the seat and nature of on the surface of these bones is effected. In 



obscure hock-lameness are now maintained by the 10th volume of the " Veterinarian,'' are 



the majority of veterinary surgeons, although some valuable observations on this subject by 



some of them differ a little "with regard to the Professor Dick, and Messrs. Pritchard and 



articulation that is generally affected, and the Spooner. 

 manner in which the depressions or excavations 



