17. The means of reduction vary according to the different kinds
of displacement. They are all, however, founded on nearly the same
principles, and it will be easy to form proper ideas of them, when we
shall have given an account of the means necessary to be employed in
luxations backward, of which the others are only modifications.
Here genius seems to have been as prodigal of resources, as nature has
been of obstacles. Indeed, to accomplish the reduction, we sometimes
see the surgeon placing his elbow in the fold of the affected arm,
interlocking his fingers with those of the same limb, and, then,
bending with his whole force, both his own fore-arm, and that of the
patient, to effect at the same time extension, counter-extension, and
reduction or conformation: at another time we see him fixing the fold
of the injured arm against some resisting body, such as a bed-post;
and while an assistant, then, pushes the displaced olecranon against
this body, he himself, pressing on the shoulder with one hand, and
grasping the fore-arm with the other, bends it forcibly, in order,
by that means, to produce a replacement: again, a body of some size,
being placed in the fold of the arm, serves as a fulcrum, on which the
fore-arm, being suddenly flexed, moves and acts like a lever of the
first kind, of which the power, being applied at the extremity next
the hand, draws it backward and upward, and by that means pushes in
a contrary direction its luxated end, where the resistance is made.
On some occasions, the fore-arm of the diseased side, bent at a right
angle, is placed on a horizontal table, and, while the lower extremity
of the humerus is thus resting on the table, the surgeon pushes
it backward with one hand, and with the other, taking hold of the
extremity of the fore-arm, draws it in a contrary direction.
18. The ancients employed the three first modes. Pare has had
engravings of them made: Scultel has also given figures of them as
practised by Hippocrates. The Arabians knew of no other modes, nor did
their descendants, who were only compilers from them. The practitioners
of our own day still continue their use. But, in general, they are
chargeable with the numerous inconveniences and faults of producing
intense pain, of not being completely under the direction of the
surgeon, of bringing the point of luxation too near to the place on
which counter-extension is made, and of bruising and doing violence to
the parts: nor do they disengage, by means of previous extension, the
luxated ends of the bones, to facilitate their replacement in their
natural situations.
This last charge is not applicable to the last of the processes
proposed by Petit. But, here, the extending forces are most commonly
insufficient; the surgeon, having both his hands engaged, is not
able to act on the joint to assist in the replacement: and the
counter-extension made is too near to the point of luxation.
19. In common cases, Desault employed a method as simple and more
efficacious, which few writers have recommended, and none have
described with accuracy.
The patient is, indifferently, either seated or standing. The fore-arm
being half-bent, an assistant takes hold of the extremity next the
hand, to make extension; another, to make counter-extension, takes
hold of the humerus a little below its middle, with both hands, the
fingers crossing before, and the thumbs behind. The extension is
made gradually, and when it begins to move the olecranon, and draw
it from the place it accidentally occupies, the surgeon, to aid in
the reduction, grasps the lower end of the humerus with both hands,
crosses his fingers in the fold of the arm, applies his thumbs to the
olecranon, and drawing the first backward, pushes at the same time the
latter forward; thus, he favours, on the one hand extension, and on the
other counter-extension, and in that way finishes the reduction.
20. This method is most commonly practised with success, in recent
luxations, where we have oftentimes seen the reduction effected at
the Hotel-Dieu, by the simple process of pushing, as just mentioned,
the olecranon forward, the humerus being held backward, without any
previous extension, while the fore-arm was merely supported by the
assistants.
21. But the luxation being oftentimes of long standing, presents
very great difficulties. What means must then be employed? It is an
established principle, that the force with which a power acts, is
in direct proportion to its distance from the point of resistance.
Augment this distance, and the extending forces, being doubled and
even trebled, will more easily dislodge the luxated extremity. But
this indication is fulfilled, by two long straps, formed each of a
towel folded several times, one of which is fixed above the wrist,
and the other round the humerus a little below its middle. Extension
is then made at their extremities, and is almost always sufficient,
when aided by skilful efforts of the surgeon (19), to accomplish the
reduction. The application of a strap round the humerus is never
necessary, unless when the resistance is very great; because, in
counter-extension, it is requisite only to withstand or bear against
the efforts of extension, but not to act in a contrary direction.
22. But in cases of this kind, the strap, placed, as we have directed,
round the lower part of the humerus, has sometimes the disadvantage of
compressing too much the brachialis and the biceps muscles, and thus
preventing them from acting; this inconvenience is particularly felt in
old luxations, where great force is employed; for, the more active then
the contraction of these muscles is, the more it will aid the surgeon
in his efforts to draw the bones into their natural situation, when
once disengaged by extension, from that which they had accidentally
occupied. If, in such a case, we impede the contraction of these
muscles, how can they fulfil this office?
23. It was this which, in certain cases, induced Desault to place his
counter-extension under the armpit, by means of a strap passing, as
in the luxation of the humerus, over a ball previously fixed in this
hollow, and crossing, not on the top of the opposite shoulder, but
behind that of the diseased side. By this contrivance the humerus was
drawn or rather held back, by a force acting perfectly in the line of
its direction. But is not this force situated too near to the centre of
motion? The strap for making extension, fastened at the wrist, answers
very well, as has been already mentioned (21).
24. Should the luxation be forward, the extension must be directed
according to the state and position in which the fore-arm is found,
which is always extended. The hands of assistants alone (19), or straps
(21), may then serve to make the extension, which the surgeon must aid,
by grasping, in a direction the reverse of that in the preceding case,
the lower extremity of the humerus, that is, by crossing his fingers
behind, and placing his thumbs on the coronoid apophysis, to push it
downward and backward.
25. The strap for counter-extension, would in such a case, always
afford the greatest advantage, by being placed exactly as in luxations
of the humerus, that is, by running to, and crossing on, the opposite
shoulder; the direction or course of the fore-arm, which is necessarily
in a state of extension, sufficiently explains this; finally, the
reduction of the luxation must be succeeded by the reduction of the
olecranon (5), and by the application of a proper apparatus to retain
the whole.
26. The reduction of lateral luxations, differs but little from that of
luxations backwards. The displaced extremities must be first dislodged
by previous extension (19). The surgeon, then, taking hold of the
lower part of the arm, places his fingers before, and with his thumbs,
crossed on the olecranon, pushes that apophysis forward and inward,
if the displacement be outwardly, but forward and outward if it be
inwardly. Does the case prove very difficult, recourse must be had
to the other means (21 and 23). The hands of the surgeon must still,
according to the direction of the displacement, assist the extension
made by the straps.
§ V.