. An American text-book of obstetrics. For practitioners and students. ectly posterior, directly anterior, left transverse, and right trans-verse. It is now held, however, that these positions do not occur, under normal conditions, innormal pelves. Since they are only found in some varieties of deformed pelves and in someother pathological conditions, their consideration is now commonly relegated to the domain ofpathology. J Dextro. 388 AMERICAN TEXT-BOOK OF OBSTETRICS. Anatomy of the Pelvis. The anatomy of the bones and the soft parts which together make up thepelvis is described in detail in
. An American text-book of obstetrics. For practitioners and students. ectly posterior, directly anterior, left transverse, and right trans-verse. It is now held, however, that these positions do not occur, under normal conditions, innormal pelves. Since they are only found in some varieties of deformed pelves and in someother pathological conditions, their consideration is now commonly relegated to the domain ofpathology. J Dextro. 388 AMERICAN TEXT-BOOK OF OBSTETRICS. Anatomy of the Pelvis. The anatomy of the bones and the soft parts which together make up thepelvis is described in detail in another portion of this work, but for the com-prehension of the mechanism of labor it is necessary to add to the anatomicaldescription a discussion of the shape and dimensions of the parturient canalas a whole, before its mechanical relation to the fetus which is to pass throughit can intelligently be discussed. The parturient canal (Fig. 211) may be divided, for purposes of descrip-tion, into three parts—the suprapelvic, the pelvic, and the infrapelvic Fig. 211.—The parturient canal: au, axis of uterus; a i, plane of inlet; rr, retraction-ring; 10, internal os; eo, external os (one-third natural size). The suprapelvic or abdominal portion of the parturient canal is made up ofthe uterine cavity and the large or false pelvis. This portion of the pelvisis classified with the uterine cavity on account of the similarity of theirfunctions; that is, the obstetric function of the large pelvis is simply that ofaffording a resting-place to the lower portion of the child during the whole or THE MECHANISM OF LABOR. 389 the greater portion of pregnancy, and of guiding the presenting part to theinlet at the beginning of labor. The pelvic portion of the parturient canalconsists of the small or true pelvis. The infra/pelvic portion is made up ofthe soft parts lying below the pelvic bones, which parts, though small andinconspicuous in the non-parturient state, are stretched out
Size: 1588px × 1573px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectobstetrics, bookyear1
