DISEASES OF THE JOINTS 441 



rare, but which has been noticed by Loiset, and quoted by 

 Zundel — the animal is stiff behind, walks on his toes, and 

 gives one the impression that he is suffering from some 

 affection in the region of the loins. 



One such case is reported by an English veterinary 

 surgeon, and we quote it here : 



' A gray gelding, and a capital hunter, the property of 

 a gentleman in this neighbourhood, became lame in the 

 near fore-foot after the hunting season of 1859. The lame- 

 ness was believed to be due to navicular disease. The 

 operation of neurectomy was ultimately had recourse to. 

 The horse subsequently did his work as well as ever, and 

 was ridden to hounds regularly till the end of the year 

 1861, when he went lame of the off fore-foot. From this 

 date he also showed very peculiar action behind, and was 

 at times lame of both hind-limbs without any apparent 

 cause. 



' In the year 1862, from the groom's indiscreet use of 

 physic, superpurgation was brought on which caused the 

 animal's death. On a post-mortem examination being 

 made, the horse was found to have navicular disease of all 

 four feet. It is worthy of note that this horse had always 

 " extravagant " action behind, but was a remarkably quick 

 and good jumper.'* 



Differential Diagnosis. — Navicular disease may be mis- 

 taken for ordinary contracted foot. It will be remembered, 

 however, that in the early stages of navicular disease con- 

 traction is absent, and that it is only when the disease in 

 the bursa is of long standing that contraction comes on. 

 With ordinary contracted foot, too, careful paring and 

 suitable shoeing soon sees a diminution in the degree of 

 lameness, and a return to the normal in shape (see Treat- 

 ment of Contracted Foot, p. 125). With navicular disease, 

 however, such shoeing as is beneficial in the treatment of 

 contracted foot (notably the various methods of giving to 

 the frog counter-pressure with ground) soon brings on an 

 aggravation of the lameness. 



* F. Blakeway, M.R.C.Y.S., Veterinarian, vol. lii., p. 21. 



