Pelvic Bones Without the Sacrum, Superior View

Description

Viewed from superior aspect, the paired ossa coxae form an open pelvic ring with the sacrum removed, so the iliac alae flare laterally while the pelvic brim traces a continuous inlet from the arcuate line of the ilium to the pecten pubis and pubic crest. Anteriorly, the left and right pubic bodies meet at the pubic symphysis on the midline; posteriorly, the auricular surfaces and adjacent iliac tuberosities mark the sacroiliac articulation sites. Portions of the acetabular rims sit inferolateral to the inlet margin, and the ischial components remain posterior and inferior in the field, contributing to the posterolateral contour. Clean bony geometry. This superior perspective is the teaching workhorse for defining the pelvic inlet and for orienting clinicians to the relationship between the arcuate line, pectineal line, and pubic symphysis when describing pelvic ring injuries. Fractures that disrupt the symphysis and one or both sacroiliac joints (anteroposterior compression and vertical shear patterns) are easiest to conceptualize when you can see the ring continuity and the posterior joint footprints without the sacrum obscuring the articular margins. It also supports discussion of male pelvic morphology, including a narrower subpubic angle and a more heart-shaped inlet compared with typical female pelvises. Use this image in gross anatomy and osteology practicals, orthopedic trauma teaching on pelvic binders and external fixation landmarks, and radiology correlation for inlet (AP axial) pelvic views where the pelvic brim is the reference line. It also fits well in publisher layouts covering the pelvic ring, sacroiliac joint anatomy, and the bony boundaries of the true pelvis. Anatomical accuracy verified by SciePro's Medical Advisory Board.