138 THE SURGICAL ANATOMY OF THE HORSE 



flexor metatarsi does not bulge inwardly, on account of the conformation 

 of the tibia, the inner surface of which bone is immediately subcutaneous. 

 Careful manipulation is necessary to detect injury to the common 

 tendon of origin to which we have referred. In this connection, how- 

 ever, the inability on the part of the extensor pedis will prove of assistance. 

 When the lower tendons of insertion are involved the hock will be 

 swollen, and occasionally the detached or ruptured tendons may be felt. 



The animal does not appear to be subjected to great inconvenience. 

 The limb will readily bear weight, a fact which immediately dis- 

 misses any suspicion of fracture. Moreover, the patient feeds well, and 

 its condition is maintained. These points were particularly evident 

 in two typical cases which came under the writer's observation, one 

 at Baird's, in Edinburgh, in 1897, and the other at the private 

 hospital of Mullet in Paris in 1901. 



Regarding the cause of the rupture or sprain, it is usually due to 

 some violent action causing an abnormal degree of extension of the hock, 

 and thus throwing undue tension on the muscle. 



Violent kicking and struggling when in hobbles and struggling to 

 release a foot which has become fixed in railway points have been cited as 

 causes. In colliery ponies it has been observed to occur as a result of 

 the heel of the animal's shoe becoming fixed beneath an upraised rail. 

 Williams states that " should the horse be old or of a weak constitution, 

 the probabilities are that the rupture is a result of degenerative disease 

 of the muscular tissue, and not a mere accident." 



Treatment consists in providing rest. The animal should be placed 

 in a box with a level surface and with scanty bedding. It is unneces- 

 sary to sling the animal, and for anatomical reasons, which will be 

 gathered from what we have already stated, blistering the limb over the 

 area which presents the enlargements will have little effect on the 

 affected muscle. It is usual for repair to take place in from one to two 

 months. If the patient is put to work too soon there is a possibility of 

 repair taking place in such manner that the tendinous portion of the 



