126 CAUSES, SYMPTOMS AND TREATMENT OP 



cases of lameness in the hind extremity are in the hock. It is oftener 

 affected than any other articulation. 



Bog^ Spavin ia a soft, puffy tumour, situated at the anterior-inter- 

 nal part of the true hock joint, and is due to the distention of the 

 capsular ligament with synovia. It bulges out where it is not bound 

 down by tendons. It is called bog spavin because it is a soft, while 

 bone spavin is a hard, condition of the hock. It is very common and 

 serious, and attacks heavy horses niost frequently, and in such is not 

 so serious. It is comparatively rare in road horses. It is more serious 

 than wind galls, from its affecting the true hock joint. It is the result 

 of an extra secretion of synovia. Naturally there are about two or 

 three drachms of synovia in this sack, but in bog spavin it may be 

 two or three ounces. As well as distention, there may be more or less 

 irritation. The capsular ligament in some cases becomes thickened, 

 and if of long standing, or if the cause is kept up, the cartilages be- 

 come affected — perhaps destroyed — and a porcelaneous deposit is the 

 result. But in many cases it will remain in just the same distended 

 condition for some length of time, and then these changes take place, 

 and perhaps caries, anchylosis, etc. 



Causes are predisposing and exciting. Horses having round, fleshy 

 limbs, etc., are predisposed. Want of regular exercise, feeding colts 

 for show purposes, fast work, sprain of the articulation, etc., are excit- 

 ing causes. It may, like wind-galls, appear very quickly. 



Symptoms are very plain. A puffy tumour, as described, involving 

 the capsular ligament ; but there may be a puffy tumour, and not be 

 a bog spavin, but just a bursal enlargement. If there is much irrita- 

 tion, there will be heat and pain, and perhaps lameness, which will 

 continue as long as the irritation exists. It is even more troublesome 

 to treat than bone spavin. 



Treatment. — If in a young horse, and there is no lameness, and you 

 are informed it has been suddenly produced, if in an animal in good 

 condition, reduce the condition by limiting the food ; apply hot or cold 

 bandage judiciously ; and you may find benefit from a combined bog 

 spavin and thoroughpin truss, but it is difficult to get it upon a bog 

 spavin, and it is a little difficult to bandage the hock; and you must 

 always leave the os-calcis free. Use judicious counter-irritation, and 

 the fall of the year is the best time to treat, for cold has a good effect. 

 If those changes are going on which are the result of inflammation, 

 then blister. Puncturing is not attended with success, for the fluid 

 will soon form again. 



Thoroughpin is found in most all well marked cases of bog spavin. 

 This is a soft and compressible tumour in connection with the bursae 

 or pedis perforans tendon. It is so called because it runs through 

 from side to side. 



Pathology. — It consists in distention of the bursa in connection with 

 the flexor pedis perforans tendon, above and in front of the os-calcis. 

 It is generally caused by more or less irritation, causing extra secre- 

 tion of the fluid in the bursa, and may be due to irritation set up 

 through bog spavin ; and in a majority of cases of bog spavin you will 

 find thoroughpin exists, due to the capsular ligament being bulged 

 upward and pressing upon the bursa of said tendon ; but the same 

 cause might produce both. 



Causes. — It is most frequent in heavy horses. It may attain a con- 

 siderable size, and does not often produce lameness, unless irritation 

 is set up ; a long, straight hock, especially in a heavy horse, predis- 

 poses to it. It is comparatively rare, but is more common in light horses. 



