340 DISEASES OF THE HORSE. 



sole, was formerly practised for It, but is now, I trust, com- 

 pletely discontinued. In short, every thing that human in- 

 genuity can devise has been tried, but nothing has ever been 

 found to cure this disorder. I believe, at this time, all vete- 

 rinarians agree in the opinion of its being absolutely incurable. 



A frequent cause of chronic lameness is a disease of the 

 lowest synovial cavity, that is, where the tendon moves upon 

 the navicular or nut bone. I have lately examined the feet of 

 two horses affected with this kind of lameness. In one, a car- 

 riage horse that had been lame two or three years, I found the 

 cavity quite dry and of a yellow colour, and on the surface of 

 the nut bone there were many minute bony excrescences, about 

 the size of millet seeds. In the second, a stage-coach horse that 

 had been working in a crippled state for some time, I found the 

 navicular synovial cavity in a similar state; but here the coffin 

 joint also was diseased. There was one part of the articulating 

 surface of the coffin bone, where the cartilage had been worn 

 away, and appeared as an ulcer, and on the lower articulating 

 surface of the small pastern there were three spots from which 

 the cartilage had been worn. 



[It has now been ascertained that the chronic disease here 

 spoken of, which used to be attributed to the contraction of the 

 foot, is almost invariably seated in the navicular joint, and that 

 contraction alone, although it may be both a cause and effect of 

 the other disease, does not, in itself, produce lameness. It is 

 therefox'e termed the navicular disease. — Ed.] 



The Navicular Joint Lameness. 



[The joint above mentioned is the seat of the greater number 

 of obscure lamenesses of the fore extremity. But although so 

 frequent, it was not till some years after the commencement of 

 the present century, that the nature and situation of the lame- 

 ness was discovered. liefore this, the shouklei's were invariably 

 pitched upon as the seat of the disease by farriers (and, indeed, 

 this is pretty much the practice with them at the present day), 

 whilst veterinary surgeons considered that when the foot was 

 contracted, that this contraction was the cause of the lameness, 

 and when it was not, that the seat of mischief was the coffin 

 joint. The great merit of pointing out the real nature and seat 

 of this before obscure disease is due to Air. James Turner, of 

 Regent Street, London, who has written various essays on the 

 subject. 



The symptoms are lameness, pointing or resting the affected 

 foot, and sometimes contraction of the foot. The lameness is 

 rarely perceptible in the walk, and is generally greatest at first, 

 diminishing or disappearing from exercise. Its degree depends 



