The Medial Part Of The Sacrum In Posterior View

Description

Centered on the median sacral crest in posterior view, the animation tracks the medial sacrum formed by fusion of S1 to S5, with the dorsal sacral foramina aligned bilaterally and the sacral hiatus opening inferiorly. Superiorly, the base of the sacrum meets the L5-S1 junction, while the apex tapers toward the coccyx; laterally, the sacral ala and auricular surfaces drift into and out of frame to keep attention on the midline landmarks. Subtle rotational and depth cues clarify the posterior contour from the thick S1 level down to the thinner inferior segments. Clear bony relief. These posterior midline features anchor both diagnosis and procedural planning. Palpation and fluoroscopic localization for caudal epidural steroid injection depend on recognizing the sacral cornua flanking the sacral hiatus, while congenital variants such as spina bifida occulta or an incompletely fused lamina can alter the appearance of the dorsal midline and the shape of the hiatus. By moving through the surface topography instead of freezing it, the sequence makes the stepwise changes in crest height and foraminal spacing easier to internalize, which is where learners often misjudge level and laterality. Use it in gross anatomy labs when teaching the bony pelvis and vertebral column, in radiology and pain medicine lectures that correlate posterior osseous landmarks with needle trajectories, and in orthopedic or neurosurgical teaching files that reference lumbosacral junction anatomy. Anatomical accuracy verified by SciePro's Medical Advisory Board.