I 



SPAVIN. 801 



CHAPTER 3S. 

 SPAVIX. 



600. Definition of Spavin. 601. Of the Hod- Joint. 602. Formation 

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

 Hod-. 604. Position of Spavin. 605. Importance of Spavin dependent 

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

 (507. Treatment. 608. Active treatment not to he adopted rashly. 609. 

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

 moved. 611. Unnervinj. 612. Examination of tJie Hock. 613. Conclu- 

 sion. 



600. Definition of Sjyavin. 



By Spavin, when unaccompanied by any prefix, is alway.s meant bone- 

 spavin. IJog spavin, thouf^h somewhat simihir in name and also occur- 

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



Spavin is an exostosis or bony enhirgement 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 l)ut 

 seldom, involved. Plate 22. 



601. Of the Hock Joint. 



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

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

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

 primarily, and l)ut 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 

 amoimt 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 he followed by effusion from the over- 

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



