248 LAMENESS OF THE HORSE 



thoroughbred liorses may be subjected to years of hard service 

 and still remain "clean limbed" and free from all blemishes. 

 Thus it seems that subjects of rather faulty conformation, ani- 

 mals having lymphatic temperaments and the coarse-bred types, 

 are prone to synovial disturbances such as thoroughpin, bog 

 spavin, etc., sometimes having both legs affected. 



Symptomatology. — Thoroughpin is characterized by a dis- 

 tended condition of the tarsal sheath which is manifested by 



Fig. 58 — Fibrosity of larsus as a complication in clironic thoroughpin. 



protrusions anterior to the tendo Achillis. However, where but 

 moderate distension of the sheath exists, there is little, if any, 

 bulging on the mesial side of the hock and but a small hem- 

 ispherical enlargement is presented on the outer side of the 

 tarsus, anterior to the summit of the os calcis. In some instances 

 the protruding parts assume large proportions, but always, be- 

 cause of the relationship between the fibular tarsal bone (cal- 

 caneum) and the tendon sheath, the larger protrusion is situated 

 mesially. 



