General Anatomy, Applied to Physiology and Medicine, Vol. 1 (of 3)

by Xavier Bichat

It follows hence, that when the granulations are united together, that the air is entirely excluded, and that what is commonly said of the contact of this fluid is inaccurate and contrary to the arrangements of nature, which knows how better than we can do by our dressings, to cover over a divided part, whilst the work of cicatrization is prepared and effected.

These are the general phenomena that cutaneous cicatrices offer in the two first periods of their formation. The internal cicatrices show nearly the same thing. Now it is easy to prove that the cellular system here performs not only an important but an exclusive part, and that all these phenomena take place in its texture or its cells. The following observations prove in a satisfactory manner the cellular nature of the granulations and the provisional pellicle that arises from them. 1st. Where the cellular system is most abundant, as in the cheeks, granulations grow most easily and wounds are soonest healed. 2d. The skin, stripped too much of the cellular texture, is not covered with ease with these productions, and adheres with difficulty to the neighbouring parts; hence the precept so strongly inculcated in surgery, of saving this texture in dissecting out tumours, in the extirpation of wens, cysts, &c. 3d. Maceration always reduces to this first base the surfaces of granulating wounds, when we expose a dead body that has one to this simple experiment. 4th. The nature of fleshy granulations is the same every where, whatever be the organ that produces them, whether a muscle, a cartilage, the skin, a bone, a ligament, &c.; only they are more or less backward, according as the life of each organ is more or less active, more or less decided, and the vital forces found there marked in a greater or less degree; thus they appear at the end of four or five days upon the skin, and it is very much longer before they are visible upon the bones; but their structure, their external appearance, their nature, are always the same; then they are only the expansion, the enlargement of an organ, that is met with in all the others; now this organ common to all, this general base of every organized part, is the cellular texture.

From the red colour of fleshy granulations, it has been thought that they were a vascular expansion; but their development is unlike every production of the blood-vessels. On the one hand we have seen, that the cellular texture contains so many exhalants and absorbents, that it seems to be almost made up of them; on the other hand, we shall see that in inflammation a passage is constantly given to red blood in this kind of vessels; then, as the fleshy granulations are cellular, they consequently partake of the nature of this system; and when found in a real inflammatory state, we conceive that their redness is the same as that of an inflamed pleura, of the cellular texture that has become the seat of phlegmon, of erisypelatous skin, &c.; a redness that does not imply an elongation of blood vessels, but only the passage of red blood, in those that usually carry white. This is so true, that when the inflammation is gone, the blood ceasing to enter these vessels, the membrane takes its natural colour; so that the granulations, after the formation of the cicatrix that arises from their near approach to each other, whiten because the blood no longer enters them. Now if it had been a new production of vessels, they would continue and perform their functions. Moreover, how can we suppose a development of blood-vessels where they did not primarily exist, as in the tendons, the cartilages, &c. which have, like other organs, fleshy granulations in their solutions of continuity?

Let us conclude from these circumstances, that the arterial system is not connected with the formation of fleshy granulations; that the cellular system is alone concerned in it, because that this alone is endowed with the faculty of increasing, extending, and reproducing itself.

This is what takes place in the second period of the cicatrization of wounds; the cellular texture, by the increase of power that it acquired in the first period, is raised into vesicles irregularly disposed, which exhale a white substance, that is not well understood, and unite at their superficies and form a provisional membrane. But how is this membrane changed into that of the cicatrix? Observe nature, and you will see that it brings on suppuration and a sinking down of the parts, before the arrival of this period.

Third period.

The period of suppuration does not take place in the cicatrization of the bones, in that of broken cartilages, of torn muscles and generally in the reunion of all divided organs without external wounds. We must then show what relation there is between their cicatrices and those of the external organs; for a common principle presides over all the operations of nature, though they may have a different appearance.

When a bone is broken, the two first periods of its reunion are the same as those of the external organs; the ends inflame, and then are covered with cellular granulations. In the third period, these granulations, having first united together, become a kind of secretory or rather exhalant organ, which separates first the gelatine which encrusts it, and gives to the callus a cartilaginous nature, and then the phosphate of lime which completes the osseous arrangement. In the cicatrization of cartilages, gelatine only is exhaled; in that of the divided muscles, fibrin, &c.; in a word the cellular texture is the common base of all the cicatrices of the internal organs, then the fleshy granulations are the same for all; they resemble each other in each having the same base; that which establishes the difference between them, is the substance that is separated, and which remains in the cellular texture. This substance is generally the same as that which serves for the nutrition of the organ, and which is by this function, constantly carried there and brought away. Now as each organ of the different systems has its peculiar nutritive substance, each has its peculiar mode of reunion; we should understand the cicatrization of the different organs, as well as that of the bones, if the substances that nourish these organs were as well known as gelatine and phosphate of lime. The mode of development of the internal cicatrices is in general analogous to that of nutrition, or rather it is the same with this difference only, that the cellular texture rising into irregular granulations upon the divided surfaces, does not afford to the cicatrix a base formed upon the shape of the organ; hence the inequality of callus, &c.

This then is what in general takes place in the third period of the cicatrization of the internal organs: phenomena very analogous are seen in that of the external. The membrane which covers the fleshy granulations thus becomes a kind of exhalant organ which separates from the blood a whitish fluid that is called pus. But there is this difference, that instead of remaining in the texture of the granulations, of penetrating and encrusting it, as the phosphate of lime and gelatine penetrate the bone, it is thrown out and has nothing to do with the reunion; so that in internal cicatrization there is exhalation, then incrustation of the exhaled fluid, and in the external, there is exhalation and then excretion of this fluid.

Besides, an internal wound which affects the cellular texture and suppurates, appears to me to resemble perfectly serous surfaces, which are covered in consequence of their inflammation with a purulent exudation. The fine pellicle that covers the granulations is of the same nature as an inflamed pleura or peritoneum, that is, it is essentially cellular. The pus is in both cases almost of the same nature, and analogous to that of phlegmon, because it comes from similar organs, whilst if the skin alone is concerned, this fluid is of a very different nature, as we see in erisypelas.