A treatise on the science and practice of midwifery . eter of thebrim is increased, while the transverse is lessened; the relative pro-portion between the two is thus reversed. While the upper propor-tion of the sacrum is displaced backwards, its lower end is projectedforward, so that the antero-posterior diameters of the cavity andoutlet are considerably diminished. The ischial tuberosities are alsonearer to each other, and the pubic arch is narrowed. Obstructionto delivery wiil be chiefly met with at the lower parts and outlet ofthe pelvic cavity; for, although the transverse diameter of the
A treatise on the science and practice of midwifery . eter of thebrim is increased, while the transverse is lessened; the relative pro-portion between the two is thus reversed. While the upper propor-tion of the sacrum is displaced backwards, its lower end is projectedforward, so that the antero-posterior diameters of the cavity andoutlet are considerably diminished. The ischial tuberosities are alsonearer to each other, and the pubic arch is narrowed. Obstructionto delivery wiil be chiefly met with at the lower parts and outlet ofthe pelvic cavity; for, although the transverse diameter of the brimis narrowed, there is generally sufficient space for the passage of thehead. Robertas Pelvis.—Another form of transversely contracted pelvisis known as Roberts pelvis (Fig. 132), having been first described byRobert, of Coblentz. It is in fact a doable obliquely contractedpelvis, depending on anchylosis of both sacro-iliac joints, and conse-quent defective development of the innominate bones. The shape DEFORMITIES OF THE PELVIS. 375 Fig. Roberts or Double Obliquely ContractedPelvis. (After Duncan.) of the pelvic brim is markedly oblong, and the sides of the pelvisare more or less parallel with each other. The outlet is also muchcontracted transversely. The amountof obstruction is very great, so that,according to Schroeder, out of 7 well-authenticated cases the Cesareansection was required in 6. Deformity from Old-standing Hip-joint Disease.—Another cause oftransverse deformity, occasionallymet with, is luxation of the head ofthe femur, depending on old-standingjoint disease. The head of the femur,in this case, presses on the innominatebone at the site of dislocation, andthe result is that the iliac fossa onthe affected side, or both if the acci-dent happens on both sides, is pushed inwards, the transverse diam-eter of the brim being lessened. The tuberosity of the ischium is,however, projected outwards, so that the outlet of the pelvis isincreased rather than dim
Size: 1716px × 1457px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, bookidtre, booksubjectobstetrics
