Fractured Ilium, Posterior View

Description

Posterior pelvic anatomy is presented with the osseous landmarks superimposed on a male lower torso, centering on the left ilium and its relationship to the sacrum and proximal femora. The iliac crest arcs superiorly to the posterior superior iliac spine (PSIS), and the fracture line lies just inferior to that spine on the posterior iliac wing, near the posterior sacroiliac region. Medially, the sacrum sits between the paired iliac bones at the sacroiliac joints; laterally, the iliac blades sweep toward the acetabula where the femoral heads articulate. Posterior iliac fractures matter because they often behave as pelvic ring injuries rather than isolated breaks, and the PSIS level is a practical surface landmark for estimating involvement of the posterior sacroiliac ligaments and joint stability. In blunt trauma, a crack through the posterior iliac wing may coexist with sacroiliac joint diastasis or sacral injury, influencing weight-bearing restrictions and the decision between nonoperative management and posterior fixation. Bleeding and neurovascular risk are not theoretical here: the nearby superior gluteal vessels exit the pelvis through the greater sciatic foramen, and posterior pelvic approaches must respect the lumbosacral trunk as it crosses the pelvic brim. Short and sharp: pain is posterior. Use this illustration to teach pelvic bony landmarks in gross anatomy, to annotate mechanisms of injury in emergency medicine or orthopaedic trauma lectures, or to support a radiology module comparing posterior pelvic plain-film signs with CT findings around the sacroiliac joint and iliac wing. It also suits patient-facing materials explaining why a seemingly localized iliac fracture can change mobility plans and follow-up imaging. Anatomical accuracy verified by SciePro's Medical Advisory Board.