Landmarks Medical and Surgical

by Luther Holden; James Shuter

Moreover, the habit of examining the living body with ‘anatomical eyes’ and ‘surgical fingers’ teaches the eye and the hand to act together, and trains that delicate sense of touch which every surgeon should possess.

This habit is within easy reach of any one who has carefully dissected for himself, and learned what to feel for. Plates will not give him this knowledge. Let a student examine his own body with a skeleton before him. Better still that two should work thus together, each serving as a model to the other.

Teachers of anatomy should follow the example of Sir C. Bell, who was in the habit of introducing, from time to time, a powerful muscular fellow to his class, ‘in order to show how much of the structure of the body, such as the articulations and the muscles, might be learned without actual dissection.’[A][1]

At the same time, it is only fair to say that ‘landmarks’ cannot always be defined with precision. A considerable latitude must be allowed for natural variations in different persons. In some, their anatomy stands out beautifully clear; in others, it is masked by obesity. Selecting, therefore, for study a moderately lean person, let us begin with the head.

[A] The references throughout are to Notes at the end of the book.

THE HEAD.

3. Scalp: its density.—The great toughness of the scalp, more especially at the back of the head, is owing to its intimate connection with the cranial aponeurosis, the scalp vessels and hair bulbs intervening. This density often obscures the diagnosis of tumours on the cranium. A tumour growing upon the head may be either above or below the aponeurosis of the scalp. If below, it will have a firm resisting feel, being bound down by the aponeurosis. Nevertheless its firmness and resistance may depend not simply on its confinement beneath the aponeurosis, but on its having its origin within the skull. Look with suspicion, then, on every tumour on the head that will not readily permit you to move it about, so as to be sure of its connections prior to an attempt at extirpation.

The scalp moves freely over the pericranium, to which it is very loosely connected by areolar tissue. When suppuration takes place in this tissue free incisions through the dense scalp must be made to let the pus out.

4. Arteries of scalp.—The supra-orbital artery can be felt beating just above the supra-orbital notch, and traced for some way up the forehead; the temporal (anterior branch) ascends tortuously about one inch and a quarter behind the external angular process of the frontal bone; the occipital can be felt near the middle of a line drawn from the occipital protuberance to the mastoid process; the posterior auricular, near the apex of the mastoid process. All these arteries can be effectually compressed against the subjacent bone.

5. Skull-cap.—The skull-cap is rarely quite symmetrical. This want of symmetry is often obvious. It may occur in men highly gifted, as in the celebrated French anatomist Bichat. As to shape and relative dimensions, no two heads are exactly alike, any more than are two faces. It is beside my present purpose to go into the question of craniology more than to say that, although the cranium does not exactly follow the brain in all its eminences and depressions so as to be like a cast of its surface, yet it certainly indicates the dimensions of the great cerebral masses. The prominence of the frontal and parietal ‘eminences’ and of the occipital region may be taken as a general indication of the development of the corresponding lobes of the brain. To ascertain the relative proportions of these three regions, let a thread be passed from one meatus auditorius to the other, across the frontal, parietal and occipital eminences respectively.