94: TEEATMENT OF DISEASES 



should know, that the joints of the hock are composed of several 

 bones, two of which form the joint proper, the remainder, eight in 

 number, are concerned in the articulation and composition of the 

 same. Between each bone is inserted a cartilaginous cushion for the 

 purpose of warding off concussion, and thus preventing injury to the 

 bones, which would otherwise occur. These bones have all their 

 proper capsular membranes, which separate one from the other, mak- 

 ing them distinctive points. A synovial membrane pervading the 

 whole, furnishes synoy/a, {'■^ joint oiV) which successfully guards 

 against friction. 



Spavin generally originates in inflammation of the periosteal tis- 

 sues, (membranes proper to all bones — their external covering,) or 

 else, in the ligamentary, or cartilaginous structures, contiguous, or 

 within the joints. A high grade of inflammatory action, pervading 

 for some time, causes absorption of the cartilages between the small 

 bones, they become consolidated and immovable. This cartilage 

 behig changed into bone, cannot possibly be restored, and is there- 

 fore incurable. 



Spavin having, in this manner, zninternal origin, is not percepti- 

 ble ; consequently, some persons are unwilling to admit its existence 

 until they can both see and feel it. If it shall commence externally^ 

 (on the inside of the hock) in the form of encrustation, termed exoS' 

 tosis, which is very often the case, all doubt is at an end. In plain lan- 

 guage, spavin consists in a loss of motion, between parts that were 

 once movable, and may exist with or without bony tumor. 



If a student were asked the question, What constitutes a spavin ? 

 he would answer, '■'■Anchylosis and exostosis of the tarsal (hock) 

 bones." Ask him if it can be cured, and he utters a decided "No." 

 He only mitigates the lameness. 



The malady is similar to that occurring among children, known as 

 hip disease, when the head of the thigh bone unites to the pelvis ; 

 and no one pretends, at least never succeeds, in effecting a radical 

 cure. But, as regards the horse, the disease is more complicated, 

 because a greater number of bones are involved ; yet in effect, the 

 disease is less serious, because it does not prevent flexion and exten- 

 sion of the joint proper. 



In a very brief manner I have now considered the pathology or 

 nature of spavin, much interesting matter (and really valuable to 

 students) is necessarily omitted, in order to render the article brief 

 as possible. 



Cause of Spavin. — Its pathology demonstrates inflammation of 

 one or more tissues proper to the point, which is produced by over- 

 work, sprain or concussion ; the tumor and transformation of the car- 

 tilages into bony substances, always being preceded by lameness, 

 indicates injuries of this character, yet they are not in all cases op- 

 erative ; for some of our truck horses, especially those used in shafts, 

 are often compelled to perform extraordinary feats of strength, that 

 would in ordinary horses induce ligamentary lameness, ultimately 

 resulting in spavin, yet they are remarkably free from it ; the reason 

 is, they are free from predisposition. 



It is a fact, well known to the profession, that many spavined 

 horses labor under either local or constitutional predisposition. 



