46. By what means then can this indication be effectually fulfilled? By
that which will perpetuate, throughout the whole treatment, the action
of those means by which reduction was effected; by that which, to the
ever active power of the muscles, will oppose a resistance constant in
its action; by that which, forming on the exterior of the thigh a kind
of artificial muscle, may become an antagonist to the natural muscles
of the part, and neutralize their efforts, by acting in a contrary
direction, and which, by pushing up the pelvis and retaining it there,
may prevent it from being pushed downward by the weight of the trunk
(14). But what other mean than that of permanent extension, unites
these advantages? Whatever form of apparatus may be employed to obtain
it, it is permanent extension alone that can prevent the displacement,
because it alone is founded on principles calculated to meet and
obviate the causes by which displacement is produced.
47. The ancients, though less informed than we are respecting the
nature of these causes, knew better how to appreciate their effects.
All their forms of apparatus made a permanent extension, a measure
which has been abandoned by most of the moderns, and regarded, even
at present, in France, by a great number of practitioners, as always
dangerous, and seldom useful. Let us set in opposition to the vain
fears which it inspires, a few thoughts, and much experience.
48. It is from the very object which is proposed to be attained, that
the first difficulties arise. What must we think of a limb in a state
of preternatural tension, where all the parts being overstretched must
experience an uneasiness not to be supported? I answer, that it is not
a preternatural elongation that extension produces; on the contrary,
being intended to prevent a preternatural shortening, it has for its
object to restore the parts to their ordinary state, and to give to the
muscles their habitual degree of tension, by opposing such contractions
in them as are not habitual: under this point of view, it performs,
in relation to the muscles, those very functions which are discharged
by the bone itself, when sound and unbroken, as is fully experienced
by all patients, when the apparatus is applied. Its use not only does
not increase pain, but is alone calculated to diminish it, because, by
bringing the fragments into apposition, it prevents the soft parts from
being irritated by the points of the bones.
49. Is the swelling of the limb to be dreaded, as some pretend? But
whence can this swelling arise? From the over-stretching of the parts?
I have already proved that they are not over-stretched. From the
pressure of the straps? Perhaps this cause might produce a swelling,
if, as formerly, it were applied above the knee; but, by placing it, as
Desault did, near to the ancle, by surrounding, with a thick compress,
the lower part of the leg, where the straps pass, and by securing the
foot with a tight bandage under the straps, if their action be dreaded,
this fear must be done away; and, besides, experience, which is the
only true test of the dangers of a process, by no means justifies the
apprehension. The venæ saphenæ and the absorbents that accompany them,
are free from the compression, which bears principally on the tendo
Achillis, and the malleoli.
50. What shall we say in reply to the censure thrown on the process of
permanent extension, in the memoirs of the academy, where it is charged
with having been oftentimes productive of ulceration and even gangrene,
in consequence of the pressure of the upper strap? What method can
escape censure, if it be unskilfully pursued? What process will not
be injurious, if mutilated and ill managed by ignorance or a want of
discretion? To represent the thing properly, let us suppose the worst:
a circular bandage, in consequence of being drawn too tight, produces
mortification in the subjacent parts; must circular bandages be on
this account entirely rejected? An unskilful hand, in an operation for
cancer, opens the axillary artery; must we therefore cease to search
under the arm-pit for schirrous glands?
51. Permanent extension is, say some, insufficient to overcome muscular
action; it is opposing to a power equal to 1000, a resistance equal to
only 100. But this force of the muscles, which is oftentimes so great
at the time of reduction, diminishes gradually, by the pressure of
the bandages, by the immobility of the limb, and, above all, by long
continued extension; for a continued effort equal to 10, will soon
perform what could not be effected by a temporary exertion of a force
equal to 100. Let us pass over the more minute objections made against
permanent extension, and search among the different modes of performing
it, that to which practitioners ought to give a preference.
52. We may throw into two classes the general modes proposed by
different authors for effecting permanent extension. Under the one are
included those modes requiring simple means, such as straps, splints,
&c. while the other embraces such as, from being complex, necessarily
call for the use of different machines.