Bony pelvis (inferior view) (English)

The pelvic outlet (a.k.a. inferior pelvic aperture) is the inferior opening of the true pelvis. It is formed anteriorly by the pubic arch, ischiopubic rami and ischial tuberosities, and posteriorly by inferior borders of the sacrotuberous ligaments and apex of the coccyx. Since the latter structures are both slightly yielding, this results in a less rigid posterior half of the pelvic outlet.