248 
W. L. ZUILL. 
the sub-acute form, leaving all the structures of the hock thick¬ 
ened, indurated and inflamed, with marked impairment of its- 
function. The bones of the articulation are the seat of an active 
inflammatory process, which comprises the articular cartilage, 
and the synovial membrane, making it impossible for the animal 
to carry weight comfortably upon the injured extremity; and is 
of itself sufficient cause for lameness. The periosteum is thick¬ 
ened and inflamed, sore and sensitive; the ligaments and ten¬ 
dons attached to it functionally agravate the lesion and intensify 
the lameness. The Cunean tendon of the flexor metatarsi is also 
compromised in this lesion; it is found indurated and vascularized, 
often to such an extensive degree, that it loses its tendinous 
character; its white glistening appearance is changed, and a red 
vascular structure takes its place. Associated with this is an 
inflammatory transudation, into the tendinous synovial bursa 
with vascularization of its walls, and hypertrophy of its fringes. 
Either of these lesions are sufficient to produce an intense lame¬ 
ness with symptoms and history of acute spavin. These trau¬ 
matic complications of the hock joint can easily be diagnosed, 
because of the fact that they are always associated with a diffused 
induration of the entire articulation. 
Given a case of hock lameness, however, with symptoms and 
history of acute spavin without the diffused swelling and in¬ 
duration, and it will always be found to have arisen from other 
causes than traumatism. 
Lesions of tiie Tendon .—That form of acute spavin due to^ 
localized lesion of the cunean tendon can always be easily diag¬ 
nosed from other acute lameness of the hock. The lameness is 
very intense, the animal stands in the stall with the leg flexed 
well up to the belly, and it is difficult to make him carry any 
weight upon it; but after going some distance upon three legs he 
may lightly touch the toe to the ground. By elevating the front 
foot on the lame side the animal is compelled to place the lame 
leg upon the ground in order to maintain his balance, then a 
digital examination can *be made. The abnormal heat of the 
parts is limited to the region occupied by the tendon, which can 
