Figs. 27 to 22 represent rachitic women, observed by my colleague, Bailly.
The woman in Fig. 17 had a pelvis measuring 2.7 inches in the con jugate, after deduction. One premature labor at eight months, one labor at term, delivery by forceps. Living child.
In Fig. 18, the pelvis measured 3 inches. Two pregnancies. Issue the same as above.
Figs. 19 and 20, a multipara, conjugate of 3.5 inches. Five labors at term, one at t3rm with prolapse of cord. Five living children.
Figs. 21 and 22, pelvis of 2 inches. Cwsarean section at term. Living child, mother died on fourth day.
The pelvis presents the following characteristics: 1. The bones as a whole, are abnormally small, the sacrum is short and straight. The iliac bones are so thin as to be almost transparent in some places.
2. The sacrum is depressed and rotated on its transverse axis. Its con cavity may disappear, the bone being straight or even convex. The pos terior iliac spines project prominently over the posterior aspect of the sa crum, the bodies of the vertebra3 (especially that of the first) are much compressed posteriorly.
3. The distance between the crests of the ilia is less than that between the anterior superior spines.
4. The pubic arch is increased, the ischial tuberosities are more widely separated than normal, and the cotyloid cavities are directed more anterior ly, the pubic symphysis is flattened (or is even convex posteriorly) and thus tends to approach the promontory.
5. Since the pelvis is flattened in this manner, the conjugate diameter of the brim is always shortened, and this shortening is generally in pro portion to the degree of malformation of the pelvis.
6. The oblique diameters of the superior strait are also diminished in length, but this shortening is not constant.
7. The transverse diameter may be of normal length, or even longer.
8. The sacro-cotyloid measurements are considerably diminished.
9. According to Schroeder, all the diameters in the cavity are length ened; but Depaul states that the right oblique diameter is always shorter than normal.
10. The diameters at the outlet are usually normal, or the transverse and conjugate may be slightly increased.
11. The entire depth of the pelvis is diminished, as well as that of the sacrum and symphysis pubis.
12. The anterior inclination of the pelvis is lessened in proportion to the depression of the sacrum.
13. The average weight of the pelvis is notably diminished (10 to 16 ounces, the normal being 24 ounces.) 14. Around the edge of the superior strait, especially in its anterior half, are sharp projections and spines, which may cause serious lesions of the soft parts, in consequence of prolonged pressure, during labor. The pubic crest and ilio-pectineal eminence may be the seat of these sharp knife-edged projections, which may be either unilateral or bilateral. In the living subject these edges are, of course, covered by the soft parts, the spine of the pubes, in particular, being enclosed in such a thick cov ering that it rarely does any harm. In certain cases, however, when the pelvis is contracted and labor is prolonged, if the head is compressed for a long time at the superior strait, a lesion may be produced in that part of the uterus which is caught between this sharp projection and the head, or between the promontory and the head, and the organ may even be perforated.
The Pseudo-ostarmalacte-rachitic Pelvis.
In this variety the promontory is deeply depressed by reason of the tilting of the sacrum, the bone presents an exaggerated curve, which causes its two extremities to approach each other, the cotyloid cavities are ap proximated, and the symphysis projects forwards. The superior strait has a triangular shape, the ilia curve inwards, and seem to be folded upon themselves. This deformity naturally results when infants are made to walk while their bones are still in a condition of rachitic softening. The sacrum is driven downwards into the pelvis by the weight of the trunk, while the acetabula are forced inwards by the counter-pressure exerted by the heads of the femora.