SPAVIN. 301 



CHAPTER 38. 

 SPAVIN. 



600. Definition of Spavin. 601. Of the Hock Joint. 602. Formation 

 of Spavin. 603. Liability to Spavin dependent on the conformation of the 

 Jlock. 604. Position of Spavin. 605. Importance of Spavin dependent 

 on its position. 606. Peculiarities of Lameness arising from Spavin. 

 607. Treatment. 608. Active treatment not to be adopted rashly. 609. 

 Of spavins which do not produce lameness. 610. Spavins cannot be re- 

 moved. 611. Unnerving. 612. Examination of the Hock. 613. Conclu- 

 sion. 



600. Definition of Spavin. 



By Spavin, when unaccompanied by any prefix, is always meant bone- 

 spavin. Bog spavin, though somewhat similar in name and also occur- 

 ring in the hock, has no connection with this disease. 



Spavin is an exostosis or bony enlargement in the region of the hock. 

 It is usually found to involve two or more of the weight-bearing bones. 

 The inner small metatarsal bone of the leg is sometimes, though but 

 seldom, involved. Plate 22. 



601. Of the Hock Joint. 



The conformation of the Hock generally has been dwelt upon in the 

 precedig Chapter. The true hock joint, it will be remembered, consists 

 in the articulation of the tibia and astragalus. The joint is never 

 primarily, and but seldom even ultimately, except as a result of open 

 joint, affected by exostosis. 



But besides the true hock joint, there are also joints with a limited 

 amount of motion between each of the other bones, which make up the 

 structure of the hock. Plate 22. The exostosis known as Spavin gene- 

 rally forms between two or more of these bones and interferes with their 

 gliding motion ; or it may form on the outside of the bones, or partly on 

 the outside and partly between the bones. As stated above, it very 



rarely extends to, or implicates the bones of the true hock joint. 







602. Formation of Spavin. 



When from undue concussion, pressure, sprain, or such like causes, 

 irritation is set up either in or in the neighbourhood of the above- 

 mentioned bones, it is probable that the irritation will be quickly 

 followed by inflammation, more or less severe according to circumstances, 

 of the periosteum and articular surfaces of the bones implicated. Inflam- 

 mation will, as usual, probably be followed by effusion from the over- 

 loaded blood-vessels of the part. In due time the watery parts of the 



