There is never in the fibrous system animal contractility, nor sensible
organic contractility. Organic sensibility and insensible organic
contractility are found there as in all the other organs.
The animal sensibility exists in it in the natural state; but it
appears in a peculiar way, of which no system in the economy, I
believe, offers an example and which no one has precisely pointed
out. The ordinary agents that put it in action, such as the different
stimulants, mechanical, chemical, &c. cannot develop it here, unless
the organ is in an inflammatory state. The tendons, the aponeuroses,
the fibrous membranes, the ligaments, &c. laid bare in operations,
in experiments upon living animals and irritated in various ways do
not occasion any pain. What has been written on the sensibility of
the periosteum, the dura-mater, &c. taken in this sense is evidently
contrary to observation. But if the fibrous organs are exposed to a
sudden and violent extension, then the animal sensibility is evident in
it to the greatest degree; this fact is particularly remarkable in the
ligaments, the fibrous capsules, the aponeuroses, &c.
Lay bare an articulation in a dog, that of the leg, for example;
dissect carefully the organs that surround it; remove the nerves
especially, so as to leave nothing but the ligaments; irritate these
with a chemical or mechanical agent; the animal remains unmoved and
gives no sign of pain. Then stretch these ligaments, by twisting
the articulation, the animal in an instant throws himself down, is
convulsed, cries out, &c. Finally cut these ligaments so as to leave
only the synovial membrane which exists here without the fibrous
capsule, and twist these two bones in an opposite direction; the
twisting ceases to be painful. The aponeuroses, the tendons even laid
bare and drawn in an opposite direction, produce the same phenomenon.
I have frequently repeated these experiments which prove incontestably
what I have advanced, viz. that the animal sensibility of the fibrous
system, incapable of being brought into action by the ordinary means,
is very evident in the distensions of which they are the seat. Observe
that this manner of being excited is analogous to the functions that it
performs. Separated in fact by its deep position from every external
excitement which can act upon it chemically or mechanically, it has no
need, like the cutaneous system for example, of a sensibility which
would transmit the impression of it; on the contrary, the most of
these organs, as the ligaments, the fibrous capsules, the tendons,
&c. being very subject to being distended, stretched and twisted in
the violent motions of the limbs, it was necessary that they should
communicate to the brain this kind of irritation, the excess of which
might without this become injurious to the articulations or the limbs.
Observe how nature accommodates the animal sensibility of each organ to
the different excitements it may experience, to those especially which
would become dangerous if the mind was not informed of them; for this
vital power is the essential agent by which the animal watches over its
preservation.
It is to this sort of sensibility of the fibrous system that must be
principally attributed, 1st, the acute pains that attend the production
of luxations; 2d, those more severe ones which patients experience in
the extensions necessary to reduce them, especially when, as in those
of long standing, we are obliged to employ considerable force; 3d,
the intolerable suffering of the punishment that consisted in drawing
a criminal with four horses; 4th, the painful sensation which arises
from twisting, which is occasioned by a stretching of the spinal column
and consequently of its ligaments, by turning the head too quickly,
&c.; 5th, the acute pain that those experience immediately before the
accident who break a tendon, a pain which ceases in part when the
rupture takes place; 6th, that less sensible pain which we feel when
any tendon, the tendo Achillis for example, is from a bad position too
much stretched; 7th, the great increase of pain that is experienced,
when a swelling exists under an aponeurosis, which being unable to
yield, is very powerfully raised; 8th, the painful sensation we feel
in the ham when we wish to force the extension of the leg, by which we
stretch the two oblique ligaments destined to confine this extension,
&c. &c.
It is without doubt to the insensibility of the fibrous organs to
one kind of excitement, and their sensibility to another, that must
be referred the contradictory results of the experiments of Haller
on the one part, and those of his antagonists on the other, upon the
dura-mater.
_Character of the Vital Properties._
The vital activity is much greater in the fibrous, than in the osseous
and cartilaginous systems. This is proved very evidently, 1st, by the
degree of animal sensibility which we have just observed in it, and
which is foreign to the other two systems; 2d, by the much greater
disposition of this system to become the seat of pains more or less
frequent, and especially of inflammation, &c.; 3d, by the much more
acute character that this affection has in it, as we see in acute
rheumatism, which principally affects the fibrous parts of the great
articulations of the axilla, the hip, the knee, the elbow, &c. the
aponeurotic part of muscles, &c.; 4th, moreover, by the great mobility
of rheumatic pains, which go with astonishing quickness from one
place to another, which consequently suppose a great quickness in the
alteration of the vital forces of the different parts of this system;
5th, by the greater rapidity of its cicatrization; thus by laying
bare fractures made for the purpose in animals, I have constantly
observed that the fleshy granulations coming from the periosteum and
the medullary organ, are all formed, whilst those furnished by the
bone itself have hardly commenced. I would observe in regard to this
cicatrization, that the parts of the fibrous system in which the
greatest number of blood vessels enter, as the periosteum, the fibrous
membranes, the capsules, &c. are the most capable of this phenomenon,
which takes place with much more difficulty in those where little or
scarcely any blood goes, as in the tendons, the ends of which are very
slow in uniting; 6th, we may finally be convinced of the difference
of vitality of the fibrous system and that of the preceding ones, by
the progress of an exostosis compared with that of periostosis, or a
swelling of the dura-mater, &c. Yet there is still in respect to the
vitality a remarkable slowness in this system. We see it especially in
certain affections of the limbs, in which gangrene takes place, and
makes, like the inflammation that precedes it, rapid progress in the
cellular texture, the muscles, &c. whilst that, as I have said, the
tendons that have been laid bare do not alter until some time after,
and are remarkable for their whiteness in the midst of the general
blackness or lividity.
The fibrous system presents a remarkable phenomenon; it is that it
hardly ever contributes to the formation of pus. I do not know that
after inflammations of this system, purulent collections have been ever
observed. Rheumatism, which is ranked with the phlegmasiæ, is never
accompanied by these collections; some gelatinous extravasations only
have been found around the tendons. That which was formerly taken for a
suppuration of the dura-mater in wounds of the head, is very evidently
a purulent oozing from the arachnoides, analogous to that of all the
other serous membranes. Why does this system refuse, or produce pus
with so much difficulty, or why is it not as much disposed to do it
as most of the other systems? I know not. Nor do I know that in the
midst of the cartilages collections of this fluid have been found. The
inflammations of the cartilaginous system are remarkable, because they
rarely or never terminate by suppuration.
_Sympathies._
All the kinds of sympathies are observed in the fibrous system. Among
the animal sympathies, the following are some of sensibility. 1st. In
certain periostoses which occupy but a small surface, the whole of the
periosteum of the bone that remains sound, becomes painful. 2d. After
a puncture, or bruise of the periosteum, the whole of the limb often
swells and becomes painful. 3d. In the affections of the dura-mater,
the eye is frequently affected, and cannot bear the light, a phenomenon
which may also depend on the communication of the cellular texture, but
which is certainly sometimes sympathetic. 4th. When we make extension
to reduce a luxation, and the articular ligaments consequently suffer
much, the patient often complains of pain in a very distant part of the
limb, &c.
Contractility is also brought into action in the animal sympathies of
the fibrous system. 1st. The puncture of the centre of the diaphragm
causes, it is said, in the facial muscles, a contraction which produces
a sardonic smile. 2d. The injury of the aponeuroses, the stretching
of the ligaments in the luxations of the foot and the tearing of the
tendons, are frequently accompanied by convulsive motions of the jaws
and even well marked tetanus. 3d. A splinter fixed in the dura-mater
produces contractions in the different muscles of the economy. 4th.
In injuries of the albuginea and the external aponeuroses, we often
observe similar phenomena.
In the organic sympathies of the fibrous system, it is sometimes
the insensible organic contractility that is brought into action,
and sometimes the sensible organic contractility; the following
are examples of the first. 1st. The dura-mater being inflamed, the
inflammation which always supposes an increase of the tonic forces
or of the insensible organic contractility, is often discoverable in
the pericranium and vice versa. 2d. The irritation of a considerable
extent of the periosteum often makes the medullary organ inflame and
suppurate. 3d. The articular ligaments being stretched by twisting,
all the neighbouring parts, and frequently the whole limb, swell and
become a centre of irritation in which all the vital forces of life,
insensible contractility in particular, are found much more raised than
usual, &c.
At other times it is the sensible organic contractility which is
brought into action. 1st. We often observe in the operation for
cataract by depression, that the wound of the sclerotica occasions
sympathetic vomitings, risings of the stomach, intestines, &c. 2d.
A violent pain in any part, in the fibrous system in particular,
increases very much the sensible organic contractility of the heart
and thus produces from sympathy an acceleration in the motion which
it gives to the blood. 3d. I have seen a man in whom Desault reduced
a luxation, and who, from the great pain which the stretching of the
ligaments gave him, was unable to retain his fœces, so great was the
contraction of the rectum.
We see that in these sympathies, it is sometimes the fibrous system
which exerts its influence upon the others, and sometimes they exert
their action upon it. It is principally when it is drawn, when the
peculiar kind of animal sensibility which it enjoys is put into action
that it occasions in the whole economy a remarkable sympathetic
derangement. I presume the ancients considered as nerves all the
white parts, the ligaments, the tendons, &c. on account of the very
serious accidents they had observed from their stretching in sprains,
in complicated luxations of the knee, the elbow, the ankle, luxations
which can never be produced without a violent stretching of many
ligaments, of aponeurotic and tendinous parts, &c. A stroke of a sabre
which divides the ligaments of the tarsus, a body which bruises them,
produce consequences much less serious, than a false step that twists
them. This leads us to an important general consideration, the truth
of which is proved by the examination of the other systems; viz. that
it is the predominant vital property in a system, which is especially
brought into action by sympathies. As the animal sensibility, capable
of responding to the agents of distension, is here the most strongly
marked, it is this that performs the principal part in the fibrous
sympathies.