182 VETERINABY MEDICINE AND SURGERY. 



lesions. They seldom produce severe or permanent lameness. When 

 they do, or at least are supposed to do so, the cause of the lameness is 

 generally sprain of the ligaments or tendons or of their sheaths, and the 

 external enlargement is only a result. In some cases, however, the en- 

 largement becomes of so great a size as to be a serious blemish, or even 

 to incapacitate the horse for fast work. 



Occasionally in recent cases, arising from severe sprain, we find the 

 bursa or sheath evidently full of synovia, whilst its walls from distention 

 have become very thin. This is especially apt to be the case in the hock. 

 Such cases must be treated as sprains. 



BLOOD SPAVIN. 



Deflilition. — Blood spavin is a distention of the veins in the vicinity 

 of the hock. 



Etiology. — Pressure of the swelling in bog spavin impeding the flow 

 of the blood. 



Treatment. — There is no direct remedy, but any treatment which 

 lessens the bog spavin will decrease the tendency to retardation in the up- 

 ward flow of the blood. No great harm results from the dilatation of the 

 vein. The greater part of the swelling is always due to the bursal en- 

 largement, not to the vein. 



BROKEN KNEES. 



Defiaition. — Broken knees are injuries to the knees which may be a 

 simple scratch or cut or so serious as to include fracture of the bones. 



Etiology. — Always due to violence of some kind, usually a fall; bad 

 shoeing will sometimes create a tendency to stumble. 



Treatment. — If the shin is simpty l)ruised, the hair scraped off, and 

 a little blood oozing from the surface of the skin, a dressing of Kennedy's 

 Pin us canadensis or of white lotion: 



Sulphate of zinc. 



Acetate of lead .aa 3 ij. 



Water ,1 pint 



