special Injuries of Bones, Joints and Muscles. 361 



called blood spavin) wliich passes across this pari of the 

 joint. The bony swelling may be more to the front, or 

 more backward on the inner side of the hock, or it may 

 even show mainly on the outer side. It frequently im- 

 plicates the head of the shank-bone, and in bad cases may 

 extend up to the true hock-joint and even abolish its 

 movement. Lameness, which is usually present in re- 

 cent cases and is the only symptom in occult spavin, is 

 shown by moving stiffly on the toe, when the horse is 

 turned from side to side of the stall. The same stiff walk- 

 ing on the toe is seen for the first few steps in starting, 

 after which it disappears, but there remains a stiffness 

 and lack of bending in the hock and stifle joints which a 

 little practice will enable one to recognize. There is 

 sometimes, however, a jerking up of the limb as in string- 

 halt. If turned quickly in a narrow circle the animal dropa 

 on the limb, carries it stiffly or even rests on the toe only. 

 If the lameness is only moderate it will usually disappear 

 when the patient becomes warmed up at ^^■ork, hence the 

 propriety of placing him in a quiet stable for twenty 

 minutes before examination. 



Treatment. Eest ; a high-heeled shoe ; fomentations 

 and laxatives are appropriate to the early inflammatory 

 stages. Later, counter-irritants are demanded. Bhsters 

 of any kind will usually succeed. The hot iron is perhaps 

 even more efficient. Deep firing in points is especially 

 beneficial. Some cases will resist aU these modes of treat- 

 ment, but recover after section of the fiexor tendon which 

 passes over the swelling. Other methods are pursued 

 with variable success. All may do well in young horses with 

 no constitutional infirmity, and all will fail in some old 

 subjects. 



INFLAMMATION OF THE TRUE HOCK JOINT. BOG SPAVIN. 



Inflammation of the upper or principal joint of the hock, 

 where nearly all the movement takes place, occurs from 

 overwork, sprains, rheumatism, punctures, wounds, fi'act- 

 31 



