DISEASES OF THE TENDONS AND TENDON SHEATHS. 
757 
ovei-distended, forms an elastic swelling, varying from the size of a wal¬ 
nut to that of a man s fist. The condition is oftenest seen in riding- 
hoises, being caused when the animal is thrown on its haunches. As 
lameness is not a prominent symptom, the swelling is rarely treated, 
and only forms a blemish. 
If necessary, the parts may be blistered and fired in lines. Opera- 
1011 is not dangerous, though, when suppuration occurs, considerable 
Fig. 281.—Internal surface of the horse’s hock to show synovial sheaths, a, Tendon sheath, of 
flexor metatarsi muscle ; b, tendon sheath under inner terminal tendon of flexor metatarsi; 
c, tendon sheath of flexor accessorius ; cl, tendon sheath of flexor perforans ; e, e , tendon 
sheath of flexor perforates and gastrocnemius muscles ; /, f , distended synovial capsule 
of the true hock-joint. 
thickening always remains, and the remedy becomes worse than the 
disease, because everyone knows that the latter is of little importance. 
(c) Distension of the sheath of the flexor pedis perforatus. At the 
spot where the flexor pedis perforatus comes in contact with the posterior 
or upper surface of the tendo Achillis, and about eight inches above the 
point of the hock, a tendon sheath begins, which extends downwards, 
and sometimes becomes the seat of extensive swelling. In coarse-bred 
horses, it sometimes affects both limbs, and forms above the tuber 
calcanei a longish swelling as large as a child’s head, divided into two 
