Lectures on the principles and practice of physic : delivered at King's College, London / by Thomas Watson.

  • Watson, Thomas, Sir, 1792-1882.
Date:
1844
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Licence: Public Domain Mark

Credit: Lectures on the principles and practice of physic : delivered at King's College, London / by Thomas Watson. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    3dly. Hypertrophy may even be consistent with no alteration of shape, or increase of bulk in any direction, the organ occupying exactly the same space, and preserving the same absolute dimensions as before, but becoming more full of component particles, more compact, heavier. This state is well exemplified in certain cases of hypertrophy of bone: the spongy or cancellous texture of the bone disappears—its specific gravity is increased— it becomes hard, firm, and like ivory. The structure appears, to the eye, to be changed, yet remains the same, except in respect of its density. I have told you that hypertrophy is usually a conservative and salutary change. We shall meet with many illustrations of this as we proceed. But I may take the present oc- casion of pointing out to you some of the beneficial tendencies of this change when it takes place in bone. For, since the diseases of the bones do not belong to my province, I shall have no other opportunity. You probably know that in the disorder called rickets, occurring principally in child- hood, the bones are soft, and deficient in their more solid ingredient; so that they bend under the weight of the body or the contraction of the muscles attached to them: after a certain period this disproportion in the constituent particles of the osseous tissue ceases; but the bones are permanently distorted, and, therefore, less adapted to their office, and less strong, than if they had remained straight. Now the natural remedy that ensues is very striking and beautiful. The bent bones become hypcrtrophied'm certain places; they grow thicker, denser, harder, and, consequently, stronger, at the very concave part where the stress of the pressure is the greatest. The following experiment showed the same thing in a somewhat different manner. An inch of the middle part of the fibula of a quadruped was cut out. A long time afterwards the animal was killed. The tibia was then found to have become considerably thickened exactly in that part of it which corresponded to the defect in the fibula.* The same principle appears still more conspicuously in a case of disease related by Cruveilhier. He saw in the hospital at Limoges a young man who had lost (from necrosis with suppuration) the middle third of his tibia; of the larger of the two bones of the leg. The lost bone had not been reproduced, but the fibula, the naturally slender bone, had become thick and strong enough to support the whole weight of his body. I was explaining to you that hypertrophy may exist, without enlargement. On the other hand there may be enlargement, without any change of structure, and yet no hyper- trophy. The liver and spleen are apt to acquire a considerable increase of bulk from mere congestion and distension of their vessels by blood. An immense spleen will shrink into its proper size in a few hours, after haemorrhage from the stomach, whereby the gorged venous system of the abdomen has been lelieved. Dr. Townsend mentions a remarkable example of the same kind respecting the liver. The inferior cava had been compressed by an aneurismal tumour, so that the passage of blood from the liver was greatly impeded. Under these circumstances the liver became so large as nearly to reach the crest of the ilium. Suddenly the aneurism burst, the pressure was taken from the cava, the hepatic veins were allowed to empty themselves, and before the body was opened for inspection, the liver had nearly resumed its natural situation and dimensions. Of the causes of hypertrophy little more is known than I have already told you. The most important circumstance for you to remember is that increase of function produces increase of nutrition. This is nearly a general fact; but whether the converse proposition be as generally true—whether hypertrophy of a part always denote increased activity in its function—is much less certain. If that were ascertained, we might hope to discover the actual office of certain parts of the body, the uses of which we do not yet understand (of the thyroid gland, for example), by investigating the circumstances under which they become subject to hypertrophy. In Mr. Mayo's Outlines of Human Pathology, a case is related of hypertrophy of the tongue, in a young child, treated by Mr. Hodgson, of Bir- mingham. It would seem to be impossible to account for this by any increased energy in the known functions of that member. A few isolated facts, bearing upon some points connected with this inquiry, have been made out. * Mr. Stanley's Lectures, Coll. Surg.