DEPARTMENT OF SURGERY. 
55 
and most experienced surgeons report but few bad results, while 
the less experienced often discard the operation entirely, owing 
to a repetition of serious sequelae. In looking over all of the 
available literature on the subject, we find a variety of opinions 
as to the cause of this unfortuate termination, among which 
are: (i) Removal of the trophic innervation, (2) Inflammation 
of the pedal vessels, (3) Suppurations from nail pricks, corns, 
and wounds which escape timely notice, (4) Mechanical vio¬ 
lence to which the diseased part is subjected after removal of 
the lameness. It is our opinion that the latter is the one and 
only cause of break down from nerving. Whenever the 
lameness is removed by unnerving, the diseased part is at once 
required to fulfil the mission of a healthy structure. The part 
is submitted to abuse which a diseased structure can not withstand , 
and as a result breaks down under the strain. The dissolution 
may be gradual or immediate. That removal of the nerve sup¬ 
ply has no direct effect is shown by the fact that healthy parts 
accidentally unnerved never undergo such processes. And, 
again, parts deprived of all their innervation from centric or 
peripheric paralysis are entirely immune from similar degenera¬ 
tions. A paralyzed part may atrophy from disuse, but it will 
never undergo an acute destructive process that bears the least 
resemblance to the break-down of unnerved feet. We doubt 
very much whether the eminent French and German writers, 
who refer to phlebitis of the pedal veins as a probable cause, ever 
intended that the assertion be taken very seriously. Suppura¬ 
tive processes from nails, corns, etc., are, of course, serious mat¬ 
ters in unnerved feet, but not as universally fatal as is gener¬ 
ally supposed. We have treated all manner of serious foot 
wounds in neurectomized feet, and find that only a small per 
cent, of such wounds result in loss of the foot. The wound of 
the unnerved foot will heal very slowly, and in some instances 
will refuse to heal at all, but the statement that they are fre¬ 
quently the cause of break-down can not be substantiated by 
observation. Suppurative wounds are not a common cause of 
break-down in unnerved feet. We must then look for the cause 
in the original disease for which the horse was unnerved, the 
disease which caused the lameness. To limit the number of 
serious sequelae we would then advise strict adherence to the 
following rules: (1) Never operate for a lameness due to an 
acute or subacute inflammation. (2) Never operate for laminitis 
in any form. (3) Operate only upon lameness due to chronic 
conditions, and then work the horse according to the amount of 
