PART I.

ANATOMY OF THE PARTS CONCERNED IN THE ACTS OF REPRODUCTION.

CHAPTER I.

THE PELVIS.

THE pelvis, anatomically considered, is a structure composed by the union of several bones that are respectively denominated sacrum, coccyx, ilium, ischium, and pubis, all which, being arranged in their proper places, and bound together by cartilages and ligaments, covered with tissues of various kinds and provided with certain important viscera within, and with other organs on the exterior, require no little study and reflection by those who design to learn obstetricy in order to acquire a competent knowledge of the art of midwifery. It is the duty of the anatomist to particularly describe all those parts, and point out their relations to each other and to the whole economy; but, in the view of the obstetrician and accoucheur, the pelvis is seen to be a bony and fleshy canal, designed to contain, support and protect the organs of generation, and give passage to the fruit of the womb.

It is owing to the peculiarly complicated forms of the pelvic canal, that the act of parturition in women is more difficult, painful, and dangerous than in other mammiferous beings, for it is to the peculiarities of that canal that is due the power possessed by women to give birth to their children by what is called a vertex presentation, a thing impossible in all other mammifers, even those most nearly allied by form to the human family. There is not one of them that does not present its offspring in what is called the face presentation, the muzzle and not the back of the head, or vertex, being the presenting part. In our race the ratio of volumes of the foetus and pelvis ought to be carefully studied by every conscientious student, who can never duly comprehend them until he has first become

acquainted with every bone that makes part of this interesting and curious organ. Hippocrates long ago compared the child in its mother's womb to an olive in a narrow-necked bottle: If one of the poles of the olive presents itself to the opening, it can readily pass out; but if it presents itself transversely, its position must first be changed before it can come forth, or else the olive or the bottle must be broken for its extrication. Hence the subject of presentations is a most important one in relation to the study of the pelvis.

If the pelvis does offer the most considerable of those obstructions and embarrassments that are met with in the practice of Midwifery, and if the relation of it to the child is of such vital importance in our proceedings, then every just, wise, and earnest student of obstetricy will feel himself bound to carefully inquire into its nature and properties, and he will, I am sure, discover that, while dry and uninviting in its particular details, it is, as a whole, clothed with the very highest interest. This lively interest in the study of the pelvis is, however, not confined to its mere midwifery connections: for, as all the organs of reproduction in the female are laid either within or upon the pelvic bones, so their whole life, power, and offices, as well as their places and positions, are inseparably allied to, and dependent upon their osseous basis, without which they could never be developed nor exist. A professional man ought to know these parts so well as to have attained to the possession of a perfect ideal of them, having them intellectually or spiritually drawn on the tables of his mind as an ever present model with which to compare every medical case in the category presented for his opinion and judgment. With such an intellectual ideal model ever at hand, he could measure every faulty form, crasis, or function, and every deviation in place, and so become, as it were, incapable of making mistakes in diagnosis or action; his ideal pelvis, and its apparatus, would for him be the norm, all that should agree with it being normal and all others abnormities.

The word is derived from the Greek aus, which corresponds to our English word basin. The Latin word pelvis has become a part of our technical, and indeed of our ordinary language, as it is of the French didactic language, according to Prof. Dubois. Its true interpretation is hips or hip-bones, or haunch or haunch-bones. We do not usually employ, to express its idea, the English word basin, while the French mostly call it le bassin. Italians speak of it as il bacino, the basin; Germans denominate it das becken, the basin; Spaniards, la pelvis, the basin; and Swedes call it backenet, the basin; whence it appears that the idea of a pelvis has some connection with the idea of a basin in all the above named languages.

Fig. 1.

The annexed figure (Fig. 1), which represents a well-formed female pelvis, drawn in outline, exhibits this resemblance to a basin, though faintly, and the fainter, indeed, because the whole upper edge or front side of the bowl seems to be broken away, both above the front or pubic bone, and below it at what is called the arch of the pubis. The great upper vacuity is seen in the

drawing between the two angular points, one on the right and the other on the left side of the drawing-projections that are known as the anterior-superior spinous processes of the ossa ilia. Beneath the front bone, or pubis, as it is called, there is another great vacuity, shaped like an arch, which is called arch of the pubis; and, indeed, the whole bottom of the bowl or basin is wanting in the dried specimen. Not so, however, in the recent subject.

But, while the whole profession everywhere agree to regard this us, pelvis, bacino, backenet, bassin, becken, basin, &c.,

and I present it here in order that he may see how naturally the writers have been led thus to divide the pelvis into a greater one above and a lesser one below, for it is evident that the lower portion of the drawing

represents a form or a cavity very different from the broad and expanded portion above. Fig. 3 shows the front segment of this same divided pelvis, and exhibits the shape of the front inner wall of the true or lower pelvis. If the two segments should be readjusted, they would reproduce the pelvis of Fig. 1. These two figures ought to instruct the student as to the real canal of the pelvis, and show him that if any difficulties should arise in the course of a labor, on account of the bony canal, those difficulties would be connected with this true, or lower or

lesser basin, and not with the great or superior basin, which is so capacious that obstruction could hardly arise within its walls. Hence he ought carefully to study the conformation and properties of this lower basin, if he would make himself equal to the responsibilities of obstetrical practice.

As the sacral bone has its sacro-lumbar facette cut so obliquely that the sacrum descends in a backward as well as downward direction, producing the projection, promontory of the sacrum, or sacro-vertebral angle, the entrance or inlet of the pelvis is rendered, by the promontory, narrower from front to rear than it is when measured either transversely or obliquely, this sharp angle of the promontory being the posterior limit of the brim. From the promontory there is a sort of raised line or ledge running round the pelvis, left and right, to stop at the top of the ossa pubis (Fig. 1), and because this raised line runs along both the ilium and the pubis, it is called the ilio-pubal line, or ilio-pectineal line. The Romans called the pubic region pecten, hence linea ilio-pectinea; for, as the pudenda is clothed with hair, the term pecten was applied to that region, and the bone of the pubis has been called the os pectinis. Juvenal speaks of the pecten in Sat. vi. 370. Inguina traduntur medicis jam pectine nigro.

Now this linea ilio-pectinea serves as a sort of stricturing band, to make the pelvis small at the inlet, and produce a narrowing there. This narrow passage, from the greater down into the lesser basin, is called the superior strait of the pelvis; all that is above it being upper basin, and all that is below it being lower pelvis, lower basin,

T

pelvic canal, excavation, cavity or true pelvis; for, by so many different names is it known in the profession. Hence, let him learn what the superior strait is-its form, and its dimensions; let him well and truly learn the shape and size of the true pelvis, and the student will find that while it has an inlet or abdominal or superior strait, it also has an outlet, inferior, or

In Fig. 4, one is looking downwards into the pelvis, and in Fig. 5 upwards through its inferior strait. In Fig. 4, the distance from promontory to pubis ought to be at least 4 inches from a to b. The distance across the opening from e to f, should be 4 inches; and the two oblique diameters, c g, c g,

of the foetus. I shall, in another page, speak of the lower strait, as consisting of a double plane.

Most of the bony resistance experienced in labors, is resistance met with at one or the other of these straits, though it is true that we sometimes meet with cases in which the excavation itself does offer very great obstruction to the birth of the child.