794 NORTH OF ENGLAND VETERINARY MEDICAL ASSOCIATION. 
class of horse that navicularthritis mostly prevails, partly owing to 
the nature of the work assigned to them, and also to their being 
condemned to the same after having previously contracted the affec¬ 
tion elsewhere. 
“ The seat of navicularthritis is the navicular joint or capsule, 
which is formed by the perforans tendon as it passes over the os 
navicularis. The structures entering into its composition, and sub¬ 
ject to the changes constituting the disease, are—bone, fibro-car- 
tilage, tendon, ligament, and synovial membrane. 
“ It may originate from a variety of causes, all, however, tending 
to the same result, viz., ulceration of one or more of the structures 
already named. Hereditary predisposition has a great deal to do 
with its production, less exciting causes being required for its com¬ 
plete development; conformation may also be classed among the 
predisposing causes, animals with short upright pasterns, stumpy 
low articulations, being more liable ; fibrous laceration of the tendon 
on its passage over the bone, forming a more acute angle in such 
states, also inevitable; or the bone itself is bruised, and undergoes 
the process of inflammation, which, if not relieved, results in 
ulceration of its cancellated structure, and gradually extends from 
within outwards, until the dense covering of bone and cartilage 
becomes involved in the same action. 
“ In animals of this formation there is greater probability of the 
disease assuming a chronic character, from the peculiar modifica¬ 
tions given rise to. 
“ Although I believe it to occur in animals of the formation 
alluded to, it is frequently met with in others of quite the opposite 
form—with good open feet, bulbous frogs, and in flat feet with low 
weak heels. In such cases I consider it to arise from a direct 
bruise from below, as by suddenly coming down upon a loose 
stone in progression. Animals that have been kept in a state of 
inactivity for some time and afterwards put to severe exertion, 
are rendered more prone to contract the disease, owing to the 
secretion of synovia being diminished from absence of the stimulus 
of movement. 
“The symptoms indicative of the disease are lameness in one or 
both fore feet; seldom in both to the same extent. Contraction is 
only associated with confirmed cases. If the foot be lightly struck 
with a hammer over the seat of disease the animal will wince. He 
goes on his toes, and, when standing in the stable, points with one or 
both feet. The temperature of the parts is variable. In progression 
he goes best up rising ground, the step being short and quick. The 
sole becomes concave, foot and pasterns more upright, and general 
action stilty or groggy. 
“The treatment required will depend greatly on the stage. In 
the primary condition antiphlogistic measures are called for— 
bleeding from the foot, hot fomentations and poultices, the sole 
having been well thinned previously with the drawing-knife. The 
animal should also be kept quiet, and cathartic and fever medicine ex¬ 
hibited. If the parts are not relieved thereby, counter-irritants should 
