PELVIC DEFORMITIES. — Pelvic de formities are comparatively rare in this country. Relative pelvic contraction, i.e., a pelvis of average size which is yet too small to admit of the passage of an overlarge child,—however, is common enough. In truth, there is no pelvis, except one very much contracted in one or all diameters, which cannot act natu rally and without assistance as the pas sage-way for the foetus. A pelvis can only be said to be contracted when a particu lar head cannot adapt itself to that par ticular pelvis. This cannot be measured; it can only be estimated. A good rule in midwifery is the following: Any head, no matter how large, which can adapt or engage itself in a pelvis, no matter how small, can safely pass through the pelvis. The only exception is the funnel-shaped pelvis, which is so exceed ingly rare that its occurrence need hardly be taken into consideration. A pelvis with normal or supernormal measure ments can be as contracted for the passage of a large unyielding head and cause the same interference as a pelvis whose size is estimated as small or much below the normal; or, on the other hand, a very decided degree of pelvic contraction or distortion is no barrier to the passage of a sufficiently small child at term.
[This statement has but too often been verified in cases where Caesarean section seemed to have been indicated. All preparations having been made for its performance, the child, though under sized, but at full term, quietly slips into the world, much to the surprise of the operator, who has to content him self with sewing up the perineum. S. MARS.] In a series of 95 cases of kyphotic pel vis, 30 per cent. of which were uni versally contracted, three-fourths of the cases terminated by spontaneous labor, one-fourth prematurely. Klein (Archiv f. Gyniik., B. 50, H. 1, '95).
Series of GO cases of labor in various forms of contracted pelvis in which 25 cases were delivered spontaneously. Gueniot (Bull. et Mem. de la Soc. d'Ob stet. et de Gynec., Apr. 18, '95).
Records of 6000 cases of pregnancy summarized in which contraction of the pelvis was noted in 654,-10 Com parison of the measurements of the head, weight, and length of the child with the measurements of the pelvis gave no defi nite results. In 87 per cent. (563 of the 654) delivery was spontaneous. In all of these cases the contraction was slight, the true conjugate being three and one half to three and one-third inches. Aus tin Flint, Jr. (Med. Rec., Oct. 26, '95).
The unknown elements in all these cases are, first, the size of the child's head and its condition, and, second, the force and vigor of the uterine action.
To measure the size of the unborn foetal head even at the present day, we must rely solely upon an estimate obtained by external means, including the adapt ability of the head to its own particular passage-way. Yet the pelvimeter and pelvimetry afford a degree of informa tion that it is not our intention to over look. Thus, narrowing of one or more of the pelvic diameters should always make us suspicious and apprehensive as to the outcome and inspire.unusual care in watching the progress of such a case. But never because of a pelvic contrac tion, except possibly where the history of prior difficult and dangerous labors is obtainable months before the advent of labor, should the patient be advised to elect any operation, until the size of the foetal head, as compared to the size of the maternal pelvis, is ascertainable.
[In doubtful cases, in view of the safety of anesthesia, examination under ether should be the rule, for then the hand in the vagina may estimate the capacity of the pelvis and the adapt ability of the presenting part. E. H.
GRArcDIN.] The generally-contracted pelvis is the most frequent form and is more apt to give rise to difficult labor than either the simple flat or the flat rachitic pelvis, because of the narrowing in all diameters and the absence of a compensatory en largement. Where compensatory en largement occurs in one or another of the diameters. Nature seems to find this wider path to force the well-flexed head through, and studiously avoids the nar rowest, most frequently the antero-pos tenor or oblique, the transverse, as a rule, being the compensatory diameter.
Accounts of 196 labors in cases of kyphotic pelvis in 113 women. Of these, 126 were full-time, normal labors; 14 were premature (3 being abortions) ; in the remaining no history was given as to the time of delivery. Of the 113 women 46 died,-14 after Porro or Csa rean section, 2 died undelivered. Neuge bauer (Monats. f. Geburts. u. Gynlik., B. I, H. 4, '95).
Critical review of the first thousand patients delivered in the obstetrical de partment of the Johns Hopkins Hos pital: In 131 cases of contracted pelves there was necessity for operative de livery 46 times, or 35.11 per cent. The pelves most frequently requiring opera tion are the rachitic and the irregular forms. The generally-contracted pelvis, though very common in the negro race, is comparatively rarely sufficiently de formed to seriously obstruct labor. On the other hand, the pelves possessing a medium degree of contraction are the most perplexing, and call for the exer cise of the greater skill and judgment. G. W. Dobbin (Obstetrics, Aug., '99).