714 
DISEASES OF THE HOCK, 
upper row of small hock bones in a cat which had fallen, hind legs first, 
from a height; the metatarsus was thrust outwards. The displacement was 
immediately reduced, a rubber bandage applied, and the animal recovered. 
In a rabbit, which had also fallen from a height, Stockfleth found displace- 
ment of the astragalus. In a horse, which had passed its left hind foot 
through a hole in a wooden bridge, Haubner discovered rupture of the 
ligaments connecting the metatarsus and lower row of hock bones. The 
limb was excessively movable, and showed, at the seat of curb, a 
depression. Frick saw incomplete outward displacement of the astragalus 
in a dog ; the lower, inwardly-projecting end of the tibia was supported 
by a new osseous growth covering the inner surface of the astragalus. 
Schiadei says that one of Havemann’s pupils cured a cow suffering 
fiom luxation of the metatarsus. Townshand reports a similar case: 
the metatarsus was displaced in a forward direction. The animal 
recovered, but always went lame. In Key’s case, above cited, the union 
between the hock bones was divided, but there was no displacement. 
Stockfleth speaks of a similar case in which the astragalus and calcis 
were torn away from the cuboid and scaphoid bones ; the horse was 
killed. Ihiffeit also saw a case in which the internal lateral ligament 
and portions of the interosseous ligaments were ruptured. Union 
appears to be strongest between the metatarsus and lower row of hock 
bones , Stockfleth only gives one case of dislocation at this point. It 
occuued in a dog; all the ligaments and flexor tendons were ruptured, 
and the lower part of the limb hung by the extensor tendons. Needless 
to say, m all these cases recovery is usually extremely protracted and 
difficult, for which reason it is usually best to advise slaughter. The 
strong ligamentous apparatus, together with the prominences on the 
aiticulai suifaces of the tibia and of the astragalus, produce - so firm and 
secuie a union of the two bones that luxation of the astragalo-tibial joint 
is exceedingly rare. 
III.—WOUNDS AND ACUTE INFLAMMATION OF THE 
HOCK-JOINT. 
Wounds are by far the most frequent cause of acute inflammation 
of the hock-joint. They may be caused by thrusts with forks, lances, or 
sabres, by kicks, by the animal being trodden on, and in dogs by bites, 
or they may be due to operation for spavin or for enlarged bursas. Point 
firing.sometimes causes suppuration in the liock-joint. Inflammation of 
the tendon sheath of the flexor pedis at the inner side of the hock or 
septic or purulent cellulitis near the joint may sometimes extend to it; 
01 , again, the capsule of the joint may be opened by gangrene consequent 
on lying long in one position. Acute inflammation of the tibio-tarsal 
joint also results from metastasis, and in horses is often seen after 
