25. Here all authors seem to have been directed by the same principle.
This is to keep the shoulder of the affected side, 1st, drawn forcibly
backwards, 2dly, approximated towards the shoulder of the sound side.
Such was the practice of the Greek physicians, whom we have seen in
common with Hippocrates, Celsus, and Paul of Egina, employing a kind
of bandage, varied in its form, according to the displacement it was
intended to remedy.
Above all others, we find an application of this principle, in the
figure of 8 bandage, a particular form, which was employed in practice
by Albulasis, an Arabian, and afterwards by his countrymen, as well as
by Lanfranc, Guy of Chauliac, and their contemporaries. The use of this
bandage was continued by Pare and his successors, and has been lately
modified by several authors, such as Heister, Petit, Brunninghausen, &c.
26. But under whatever form it shows itself, its action is always
the same, and always insufficient. On comparing its effect with the
general principle, on which every apparatus for the clavicle should
be constructed (20), we perceive, that it by no means answers the
threefold indication, of retaining the shoulder backward, outward, and
upward.
27. In relation to carrying the shoulder backward it loses half of
its effect, because, its force being decomposed (so to speak) by the
obliquity of its direction, is divided into two channels. One of these
runs parallel to the shoulder and acts to no purpose, while the other,
being perpendicular to it, is alone effective; hence it must act with a
force equal to 10, in order to produce an effect equal to 5.
28. The indication, to draw the humeral fragment outward, far from
being fulfilled, is here diametrically counteracted. The scapula, being
approximated to that of the opposite side, draws the humeral fragment
towards the trunk, making it underlap the internal one, and, in this
respect, the figure of 8 bandage acts posteriorly in precisely the same
manner, during the treatment, that the contractions of the muscles did
anteriorly before the reduction.
29. Should the shoulder be supported, at such an elevation, as might
have a constant tendency to destroy the influence of its own gravity?
this is evidently prevented by the very oblique direction of the turns
of the bandage. Suspending the arm in a sling, is the only way, in
which that end can be attained. But does this mode always possess
sufficient firmness and stability? The arm, not being here sufficiently
fixed, may be constantly in motion, which, by deranging its situation,
must communicate very troublesome and injurious movements to the
fragments of the clavicle. One of the principal faults of all bandages
consists, in not preventing these movements, by restraining the
movements of the arm.
To the other disadvantages of this mode, need I add that of its making,
by the turns of the bandage, an undue compression on the projecting
edges of the arm-pit, and producing thereon troublesome and painful
excoriations?
30. From the want of a mutual correspondence and fitness between the
indications already enumerated (20), and the manner in which the
figure of 8 bandage acts, it is evident that the former can never
be satisfactorily fulfilled by the latter. Hence we may judge, what
improvement the art has received from the iron cross of Heister,
the compress of Petit, drawn transversely over the oblique turns of
the bandage, the waistcoat which Brasdor fastened round the thorax
of his patients, and the leathern apparatus, lately proposed by a
German practitioner. These means, though diversified in their form,
are similar in their effect, and, being nothing but modifications of
the figure of 8 bandage, possess, like it, the radical fault of not
offering a resistance directly opposed to the two-fold power, arising
from the muscular action and the gravitation of the shoulder.
As to what remains, it will be sufficient to show the insufficiency
of the process of reduction (22), by means of the knee placed between
the shoulders, in order to demonstrate the existence of a like
insufficiency in all those forms of apparatus, which, as Brasdor
remarks, have for their object a continuance, during the treatment, of
the effect produced by that process.
31. On the other hand, those indications will be fulfilled with
exactness, by such a form of apparatus as will render permanent the
action of the means of reduction which were employed by Paul of Egina,
by certain Arabian physicians, and by Pare; which have been renewed by
Desault, and tend to draw the shoulder upward, backward, and outward
(23 and 24).
Pecceti appears, in the last century, to have had a faint view of
the proper indication on this subject, when, under the article of
fractures, he advises the ball to be suffered to remain under the
arm during the treatment of the injury. But the figure of 8 bandage,
united to this expedient, counterbalances its effect, rendering it of
no avail, and Pecceti was therefore no more successful than others, in
obtaining a cure of the fracture, unaccompanied by deformity.
32. An overlapping more or less perceptible never failed to accompany
the consolidation or knitting of the bone, and here, as in many other
cases, practitioners laboured to explain what they knew not how to
prevent. The impracticability of surrounding the part, as in other
fractures, with a circular bandage, appeared to Heister, Petit, and
Duverney, to be the cause of this deformity. They supposed that to be
a superabundant callus, which was nothing but a displacement of the
fragments. These visionary hypotheses ceased to exist, as soon as this
displacement was prevented by a proper apparatus.
Desault sought for this form of apparatus, as well as for his other
bandages, in the multiplied application of means already known, without
inventing new ones. Bandages and compresses, easy to be procured, and
already rendered familiar to surgeons by daily use, served him for the
construction of his apparatus, for which several machines had been
already proposed.