SPECIAL INJURIES OF BONES, 361 



of the lower part of the articulation, to be seen by standing 

 Kbout two feet from the fore limb and looking across the front 

 of the joint. It is hard and to be distinguished from the tense, 

 elastic swelling caused by sprain of the inner branch of the 

 flexor tendon, and from the soft distended vein (so-called blood 

 spavin) which passes across this part 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 implicates 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 recent 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 walking on the 

 toe is seen for the first few steps in starting, after which it dis- 

 appears, but there remains a stiffness and lack of bending in 

 the hock and stifle joints which a little practice will enable one 

 to recognise. There is sometimes, however, a jerking up of 

 the limb as in string-halt. If turned quickly in a narrow 

 circle the animal drops 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 

 work, hence the propriety of placing him in a quiet stable for 

 twenty minutes before examination. 



Treatmetit. — Rest ; a high-heeled shoe ; fomentations and 

 laxatives are appropriate to the early inflammatory stages. 

 Later, counter-irritants are demanded. Blisters 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 all these modes of treatment, but recover after section 

 of the flexor tendon which passes over the swelling. Other 

 methods are pursued with variable success. All may do well in 

 young horses with no constitutional infimiity, and all will fail in 

 gome old subjects, 



