Fractured Sacrum, Posterior View

Description

Posterior sacral anatomy is presented with the median sacral crest running in the midline from the superior base toward the sacral hiatus, flanked bilaterally by the intermediate sacral crests over the fused articular processes. Four pairs of posterior (dorsal) sacral foramina perforate the dorsal surface lateral to the crests, aligned superior to inferior toward the sacrococcygeal junction where the coccyx would articulate. A transverse fracture line interrupts the continuity of the dorsal cortex and crosses the midline ridge, while the posterior sacral foramina remain patent. Bone landmarks read clearly. This posterior perspective matters because many clinically relevant sacral fracture patterns are defined by their relationship to the foramina and central canal, as in the Denis classification (Zone I lateral to foramina, Zone II transforaminal, Zone III medial involving the canal). A fracture traversing or approaching the dorsal foramina raises concern for injury to the dorsal rami and sacral nerve roots, and midline involvement prompts scrutiny for canal compromise, bowel or bladder dysfunction, and associated pelvic ring instability. Palpable posterior landmarks also guide operative planning. Reduction and percutaneous iliosacral screw trajectories depend on respecting these corridors. Use it in pelvic trauma teaching modules for orthopedic surgery and emergency medicine, and in anatomy labs covering the lumbosacral junction, sacroiliac region, and coccyx. It also fits textbook figures on posterior pelvic ring injuries, radiology primers that correlate CT axial findings with surface anatomy, and patient-facing materials explaining why sacral fractures can produce radicular pain or neurogenic bladder symptoms. Anatomical accuracy verified by SciePro's Medical Advisory Board.