982 



DISEASES OF THE LEG. 



and in draught -horses by efforts to avoid slipping. The tendon may 

 also be strained by falling from a height, or by the animal slipping 

 with the legs extended under it. In cows rupture sometimes follows 

 long periods of lying with the hind limbs flexed and violent efforts 

 to rise, as in post-partum paralysis. The injury may involve both 

 muscles or the entire tendon, or may remain confined to certain 

 portions ; the latter is, however, the exception, complete rupture 

 the rule. In small animals, like dogs, rupture may be produced by 

 the animal being caught in a door. In the horse the Achilles tendon 

 is sometimes cut through. Traumatic inflammation of the os calcis 

 or tendo Achillis, or suppuration in the tendon sheath, may also 



Fig. 532. — Rupture of the tendo Achillis (after Stockfleth). 



lead to rupture of the tendon. St. Cyr therefore distinguished 

 primary and secondary rupture. Uhlich saw rupture soon after 

 recovery from influenza. 



Symptoms. When the muscles named or the Achilles tendon are 

 completely torn away from their insertion, there is severe supporting- 

 leg lameness, inability to bear weight on the affected limb, and flexion 

 of all joints. 



The Achilles tendon extends to the point of origin of the gastroc- 

 nemii muscles, and when weight is placed on the limb serves the 

 purpose of fixing the joints, especially the hock and stifle joints. It 

 therefore fulfils an important part in supporting the body, and its 

 rupture is followed by collapse of the limb — the hock sometimes 

 descending sufficiently far to touch the ground (Fig. 532). The 

 excessive flexion of the hock increases the distance between the 



