620 
ON COFFIN-JOINT LAMENESS. 
removal of the contraction, in some instances, wholly removed the 
lameness, in others it totally failed. In some cases it appeared 
that a contracted state of the foot was itself an effect of other 
injury, though when existing* in a great degree it tended to in¬ 
crease the lameness. A comparison of great numbers of foot 
lamenesses in process of time furnished grounds of observation 
by which it could be predicted, almost with certainty, whether the 
removal of contraction would fail or succeed to remove the lame¬ 
ness. 
This distinction, available for preventing loss and disappoint¬ 
ment, formed the first step of an approach towards improvement 
in practice. The removal of contraction was effected by more than 
one process; but no process was found capable of removing, per¬ 
manently, certain kinds of lamenesses. 
On dissecting feet affected with these lamenesses, the flexor 
tendon w r as 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 
navicular bone itself has been found to have been fractured; at 
others, its surface has been seen deprived of its usual coating, and 
studded with projecting points or ridges of new growth, or exhi¬ 
biting superficial excavations more or less extensive. 
To detail farther varieties of diseased change of structure 
observable on dissection in parts connected wdth the joints of the 
foot, and arising from injury by mechanical violence, seems unne¬ 
cessary. They have all the character of being accompanied w ith 
inflammation and pain, which seldom permanently terminate 
except w ith the death of the animal. It is acknowledged that 
those parts w hich, in their healthy state, are endued with a low 
degree of sensibility, are greatly tenacious of sensibility when it 
is excited beyond a certain point. A man with a bruised or in¬ 
flamed tendon can place it, wherever situated, in a state of rest 
favourable to the dispersion of the inflammation; but this is not 
the case with the horse w r hen the flexor tendon of his fore foot 
has been injured and inflamed; for this tendon not only supports, 
passively, a certain proportion of the w eight when the animal is 
standing and at rest, but actively, whenever the limb is put into 
the slightest motion; and the horse cannot possibly place the 
tendon in a state of repose and inactivity, except during the time 
he lies on 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. The horse. 
