THERE is no subject in the whole field of obstetrics which receives so little attention in our Society discussions as that of pelvic deformities. To the relative infrequency of these abnormalities as compared with other obstetrical may be attributed the neglect which this subject receives. Though seldom encountered in practice, we are not justified in totally neglecting this important branch of obstetrical study.
The writer has endeavored to ascertain the frequency of pelvic deformity in lying in institutions in this country, wherever statistics have been published, and as a result interesting information has been obtained.
In a series 2127 cases of labor in the out-patient department of the Boston Lying-in Hospital, Dr. Edward Reynolds [Transactions, Am. Gyn. Sec., 1890.] found 22 instances of pelvic deformity, and in 100 cases of confinement in the wards of the same institution five cases were observed. Dr. James W. McLane reports 10 cases in the first 100 cases of confinement in the Sloane Maternity.
In 3225 cases of confinement attended by students at the lying-in hospital in New York City, during the first three years of its existence, in only one instance was reduction in size of the foetus demanded on account of a contracted pelvis. IOn another, premature labor was induced on account of a contraction of the pelvis in all its diameters; in not a single instance did the absolute indication for Caesarean section exist from any cause. Pelvimetry is systematically employed by the students of this school.
This is a remarkable record, and shows a much smaller percentage of cases of pelvic deformity than is generally supposed to be the case. Dr. Edgar states. with regard to the case (1154) confined during the first two years in the their lying in hospital, in not a single instance did a markedly contracted to the minor de it is not assuming too much to suppose that some of the forcep operations and cases of version were performed on account of the small size of the pelvis.
In 250 cases of labor in private and consulting practice of which the writer has record, there were three cases of contracted pelvis; one simple flat pelvis and two symmetrically small pelvis. The latter-the justo-minor pelvis-is the variety most frequently seen in women of American birth.
Among the 100 cases in the wards of the Boston Hospital, referred to in Reynold’s tables, there were 57 native women who presented one case of pelvic deformity, and that of a typical justo-minor type, the percentage of 1.75 per cent. being almost identical with that obtained among native women from the out- patient department of the same institution and the obstetrical department of the Boston Dispensary, which was 1,6 per cent. In contrast to this the remaining 43 foreign women yielded four examples of the simple flattened pelvis (9,4 per cent) and no justo-minor pelvis.
Among Reynold’s 2127 women of all classes, 10.3 per cent. possessed contracted pelvis of one variety or another. Aboard, the average is about the same. Winckel says: [Text-Book of Midwifery, p. 451.] “After all pregnant and parturient women were carefully examined as regards their pelvic relations, there were found, among 1199 births, 115 women with contracted pelvis (9 1/2 per cent), a figure which coincides exactly with those obtained of late years in the Werzburg clinic (8.10 per cent), and approaches closely to those obtained by Michaelis and Litzmann.
The first regular pelvic measurements were made in 1840-1847 by Michaelis, of Kiel, who found in 1000 parturients 131 cases of narrow pelvis (10.3 per cent).
Litzmann (1848-1886) found in 1000 parturients 149 (10.4 per cent.). Subsequent observers up to Winckel’s time found a much smaller number of cases, but the difference is undoubtedly due to the fact that more than half the cases of slight narrowing were not recognized because they produced no difficulty in labor. Winckel concludes that “we shall not go too far in making the statement that contraction of the pelvis is present in 10 to 15 per cent. of all parturient women, but that usually only about 5 per cent. are recognized even in clinical institutions on account of the effects upon labor.”
This would seem to be about the frequency in this country if we include all classes. Women of American birth are undoubtedly less frequently the subjects of pelvic narrowing than those of foreign birth. Furthermore, it may safely be concluded than an American birth decreases the amount of pelvic deformity among the children of foreign parents.
The predominance of the rachitic types of deformed pelvis, characterized by irregularities in shape of the whole pelvis and especially by flattening of the inlet by undue projection of the promontory among women of the lower classes born aboard, is probably due to insufficient nourishment and hard work before or during puberty.
The symmetrically small pelvis, due to simple arrest of development at puberty (a partial persistence of the infantile type), is the variety generally met with in women of American birth and lineage, and is due, as might be expected, to the peculiar character had habits of American women and nineteenth- century civilization.
In the practice of midwifery, the following questions are now and then presented for solution:.
1. Is there any external evidence or anything in the progress of a labor in its early stage which will enable one to suspect the presence of a pelvic deformity?.
2. What constitutes pelvic narrowing, and how are we to determine that such a condition really exists as well as the variety and degree of the deformity?.
3. Is it possible to ascertain, before labor sets in, the relation of the presenting part of the child to the narrowest diameter of the pelvic through which it must pass to accomplish delivery?.
4. Can we define, with any degree of certainty, the limitations of the different operative procedures by an approximate of the extent of the narrowing?.
I shall endeavor to answer these questions seriatim:
1. With regard to the significance of physical peculiarities in pointing out the possible existence of pelvic deformity.
While narrow straight hops and short limbs may not prove to be indicative of diminished transverse and oblique diameters, the fact that such peculiarities of shape coexist should not be overlooked. As Spielgelberg says, [Text-Book of Midwifery, vol. xi., p. 30.] when he emphasizes the importance of making pelvic measurements” “Still, the other circumstances deserve that full weight be given them, and even if they never afford more than certain points d’ appui, suggestive, to a certain extent, of the direction in which measurements should especially be made, they nevertheless assist in deciding the best treatment for special cases”.
An unusually short person, or a tall, slender woman, with very narrow hips, or lameness due to diminished length of one leg; women with abnormal curvature of the spine, or undue hollowness of the back, which is usually the external evidence and accompaniment of excessive inclination of the pelvis; none of these peculiarities should escape the eye of the careful obstetrician. They may mean nothing, or they may be suggestive of more serious defects, the detection of which, by more extended observation, will enable one to act intelligently at the time of labor, and thus possibly save a life which, without such preliminary knowledge, might be sacrificed.
The life-history of a woman with a spinal curvature or other evidences of defective development should be carefully scrutinized to ascertain if rachitis existed during childhood.
If physical peculiarities do not exist, or have been overlooked, the conditions revealed by an examination at the onset of labor may be of great value in pointing out the presence of contraction.
Failure to reach the presenting part, the non-descent of the head and the resulting protrusion of the elongated bag of waters under the influence of the uterine contractions, and the imperfect adaptation of the head to the lower uterine segment, are conditions so suggestive of either an abnormal presentation or a pelvic contraction that a discriminating diagnosis should at once be made.
The occurrence of constriction or retraction rings after rupture of the membranes, without advance of the presenting part, is evidence of obstruction, and the continuance of natural labor under such circumstance only adds to the difficulties which already surround the case.
The symmetrically small pelvic (the justo-minor pelvis) has scarcely any external signs by which we may detect it except, perhaps, narrowness of the hips in a woman otherwise of normal proportions, though it would be more natural to suspect its existence in a very short woman. Rachitis, which causes the flat pelvis, or the generally contracted that pelvis, does not always produce pelvic deformity in proportion to the intensity of disease apparent in other parts of the skeleton, and sometimes it produces no pelvic deformity whatever.
A woman with a decided spinal curvature may have a perfectly normal or even a large pelvic, the location of the deviation of the bones of more importance than the degree of it. Again, a woman may have a slight degree of pelvic deformity and yet be delivered spontaneously and successfully, especially in a first labor, the ability or failure to do so depending upon the relation which the child bears to the contracted portion of the pelvis through which it must pass in order to be delivered.
