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

PATHOLOGY OF NERVE LESIONS. 7o
the central end represent, according to this observer, Bernard's
recurrent sensitive loops, which, being divided, the
returning thread is thus dissevered from its trophic centre,
the ganglion, and therefore becomes -altered. In like
manner, Laverran explains the unchanged fibres, in the
exterior nerve end, as the recurrent fibres derived from
neighboring trunks, through which the fibrils in question
retain their connection with the nutritive centres. I have
myself observed such altered nerve tubes in the central
ends of cut nerves, but they were exceptionally rare, while
in the outer ends I have failed to notice any sound tubes
after the lapse of a certain time.
The upper end of a cut nerve remains but little altered
for a few days, after which a rapid proliferation of connective
tissue occurs, and there is a visible enlargement
formed, which, if no reunion occurs, finally gives rise to
the well-known button-like growth, which we shall have to
study in connection with the neural maladies of stumps.
The enlargement which follows simple section rarely
attains such dimensions as it does after amputations.
The peripheral end of a cut nerve undergoes inevitable
alterations, as to the exact nature of which there has
been some difference of opinion, so much so, indeed, that
I have felt it necessary to study the subject experimentally
before venturing to describe the changes in question.
These researches were made chiefly on rabbits, young or
old, and include examinations of the sympathetic, pneumogastric,
and sciatic nerves.
From the fourth to the sixth day after section, we observe
in the whole length of the peripheral end a slight
alteration of tint, consisting in a loss of transparency.
Laverran denies this, because, as he says, the removed
nerve is never transparent. I am confident, however,
that if a piece of healthy nerve be observed alongside of
the altered nerve, a difference will be seen even as early