NAVICUL ARTHRITIS. 
123 
expresses his doubts that it is not “ a complicated case” of lame- 
ness, saying,— “ When an injury has been sustained in the coffin 
joint*, happening from violent pitching of the limb on a pointed or 
hard substance, favouring of the foot occurs before any contraction 
is observable.” “ Your case has features in it which from your 
statement appear awkward; and I have put you to the expense of 
this long letter in order that you may form some opinion whether 
your horse is lame from pure contraction, or from contraction con- 
nected with deep-seated injury of the foot . The information I have 
endeavoured to convey, you may, perhaps, not thank me for; how- 
ever, if I had understood completely the facts heretofore stated 
many years ago, I should have saved myself much disappointment, 
and my employers much expense.” 
A subsequent letter of Moorcroft’s — one he addressed, in 1819, 
to the editor of the “ Calcutta Journal,” on the occasion of being 
made acquainted with the “ discovery” of neurotomy by Mr. Sewell — 
will serve as an interpretation to the above extracts from his former 
letter, and satisfactorily, I think, shew that they had relation to 
the navicular disease : — 
“ With reference to your paper of the 23d inst., noticing, as 
discovered by Mr. Sewell, within about eighteen months, a cure 
for lameness in horses, commonly called ‘ coffin-joint lameness,’ 1 
beg to observe that the mode of treatment alluded to, so far from 
being a discovery of the last eighteen months, was practised by me 
about eighteen years ago.” — “ For a long time previous to this 
period it had been fashionable to attribute most lamenesses in the 
fore limb of the horse (of which causes were not glaringly obvious 
in alteration from natural form) to some disease in the shoulder;” — 
and “ on dissecting feet affected with these lamenesses the flexor 
tendon was now and then observed to have been broken, partially 
or entirely ; but more commonly to have been bruised and inflamed 
in its course under the navicular or shuttle bone, or at its insertion 
into the bone of the foot. Sometimes, although seldom, the navi- 
cular bone itself has been found to have been fractured ; at others, 
its surface has been deprived of its usual coating, and studded with 
projecting points or ridges of new growth, or exhibiting superficial 
excavations more or less extensive .” — “ The horse cannot possibly 
place the tendon in a state of repose or inactivity, except during 
the time he lies upon the ground ; and it is subject to pressure 
invariably both in his lying down and getting up. This constant 
exposure to pressure, in addition to the nature of the parts injured, 
renders inflammation permanent, and prevents coffin-joint lameness 
receiving permanent relief.” 
There are other passages in this lengthy letter I might extract, 
* In the “ coffin” joint, as will be seen hereafter, is included the navicular 
joint. 
