RUPTURE OF THE TENDO ACHILLIS, ETC. 
709 
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 lead to rupture of the tendon. St. Cyr there- 
Fig. 262.—Rupture of the tendo Achillis. 
fore 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 
