290 



appear on the surface of their structure, to whicli tlie general term 

 of ejcostosis is applied, have had their origin in an inflammation of 

 the periosteum, or enveloping membrane, and known as periostitis. 

 However this may be we have as a frequent result, sometimes on the 

 length of the bone, sometimes at the extremities, and sometimes 

 involving the articulation itself, certain bony growths, or exostoses, 

 known otherwise by the term splint, ringhone, and spainn, all of 

 which, in an important sense, may be finally referred to the j^erios- 

 teum as their nutrient source and support, at least after their forma- 

 tion, if not for their incipient existence. It is certain that inflamma- 

 tion of the x)eriosteum is frequently referable to wounds and bruises 

 caused by external agencies, and it is also true that it may jjossibly 

 result from the s^^reading inflammation of surrounding diseased tis- 

 sues, but in any case the result is uniformly seen in the deposit of a 

 bony growth, more or less diif use, sometimes of irregular outline, and 

 at others projecting distinctly from the surface from which it springs, 

 as so commonly presented in the ringbone and the spavin. This con- 

 dition of periostitis is often diiScult to determine. The signs of 

 inflammation are so obscure, the swelling of the parts so insignificant, 

 any increase of heat so imperceptible, and the soreness so slight, that 

 even the most acute observer may fail to locate the point of its 

 existence, and it is often long after the discovery of the disease itself 

 that its location is x^ositivelj'' revealed by the visible presence of the 

 exostosis. Yet the first question had been resolved, in discovering 

 the fact of the lameness, while the second and third remained unan- 

 swered, and the identification of the affected limb and the i^oint of 

 origin of the trouble remained unknown until their palpable revela- 

 tion to the senses. Wlien, by careful scrutiny, the ailment has been 

 located, a resort to treatment must be had at once, in order to prevent, 

 if possible, any further deposit of the calcareous structure and increase 

 of the exostotic grow^th. With this view the apjjlication of water, 

 either Avarm or cold, rendered astringent by the addition of alum or 

 sugar of lead, will be 1)eneficial. The tendency to the formation of 

 the bony growth, and the increase of its development after its actual 

 formation, may often be checked by the application of a severe blister 

 of Spanish fly. The failure of these means and the establishment of 

 the diseased x^i'ocess in the form of chronic periostitis cause various 

 clianges in the bone covered by the disordered membrane, and the 

 result may be softening, degeneration, or necrosis, but more usually it 

 is follow(Ml by the formation of the bony growths referred to, on the 

 cannon bone, the coronet, the hock, etc. . 



We first turn our attention to the si)lint, as certain bony enlarge- 

 ments which are developed on the cannon bone, between the knee or 

 the hock and the fetlock joint, are called. They arc found on the 



