The Practical Application of Modern Pelvimetric Methods *

With the advent of Roentgen methods for surveying the bony pelvis have come many new concepts of the architecture of the female pelvis and its relation to the problems of labor. During the last half dozen years the quest for this newer knowledge has received an extraordinary impetus, obviously due to the excellent results in applying these new truths to practical obstetrics. Methods for measuring the pelvis by means of the Roentgen ray are various. In general, it may be said that most of them appear to be adequate for obstetrical purposes. However, it must appear that complicated maneuvers which are only successful in the hands of an expert will not be eminently useful for widespread use in a field which is as universal as is that of obstetrics. Roentgen methods to be of such utility must be adaptable to the average Roentgen laboratory and the interpretation of results must be comprehensible to the average roentgenologist and average obstetrician. It is the purpose of this communication to point out the practical essentials of pelvimetry in the light of modern knowledge, and to outline briefly the methods by means of which such pelvimetry may be satisfactorily performed. From the point of view of practical obstetrics there are three portions of the pelvis the mensuration of which will yield useful information. These are (1) the plane of the pelvic inlet, (2) the narrow pelvic plane in the lower midpelvis, and (3) the planes of the outlet. A knowledge of the various diameters of these planes will not only furnish a concept of the architecture of the pelvis, but will also give an adequate index of the available space present in the bony birth canal. In addition, this knowledge will enable us to incorporate in the prenatal history a useful and instructive record.