Injuries of nerves and their consequences - Reflex Sympathetic ...

142 INJURIES OF NERVES.
sensory ganglion, or to a group of spinal-motor cells. In
certain instances, these results are teraporarj^, in others
they are lasting, and then constitute what is
usually called
reflex paralysis, but which I should prefer to term, where
it afiects muscular motion, paralysis from peripheral
irritation.
Shock, then, is reflex disturbance, or, in some cases,
paralj'sis of centres. Why in one case the cerebrum
should suffer, in another the heart, and in a third the motor
centres of the leg or arm, is as yet inscrutable. A
hall crushes a nerve, and the tremendous shock instantly
propagated to the spine falls ruinously upon some one
of the numerous ffano-lia throus-h which it travels. Is
this because it finds a weak point, or is it that conduction
checked somewhere causes at that spot destruction from
dangerous accumulations of nerve force? Tempting
analogies here open to certain electrical phenomena, but
as yet we lack such exact knowledge as would justify
further inferences.
Theories of shock. — At the present time vaso-motor
agencies are called upon to explain every phenomenon in
disease, and for most pathologists to-day all reflex injuries
seem to be due to vasal spasm or vasal palsy in the
centres affected. Elsewhere,* together with Drs. Morehouse
and Keen, and since then in a longer essay, f I
have stated the objections to Brown-Sequard's famous
theory, which explained reflex paralysis by vascular
spasm and consequent insufficiency of nutritive supplies.
Gull, I Jaccoud,§ and the author, have all alike insisted
that permanent spasm was scarcely conceivable, or, at
all
events, that we had no distinct evidence of its possible
* IT. S. A. Circular No. 6. Keflex Paralysis. 1864.
f Paralysis from Peripheral Irritation. I^ew York Med. Jour., 1866.
X Med.-Chir. Trans., vol. xvii. Dr. Gull.
I Les Parapl6gies. Jaccoud.