Caudal Epidural Injection Into The Sacral Hiatus, Posterior View

Description

Sacral hiatus access is centered on the inferior dorsal sacrum, where the paired sacral cornua bracket the midline opening just superior to the coccyx. From this posterior perspective, the needle is positioned between the cornua and directed cephalad beneath the sacrococcygeal ligament into the sacral canal, with the dorsal surface of the sacrum forming the bony backdrop. The median sacral crest lies superior in the midline, and the adjacent dorsal sacral foramina sit lateral to the crest, reinforcing orientation on the posterior sacral plate. Landmarks are unmistakable. Caudal epidural injection relies on accurate identification of the sacral hiatus, a step that becomes challenging with anatomic variation, obesity, or prior surgery, and this illustration emphasizes the key tactile cues used in practice: the cornua as palpable posts and the hiatus as a midline depression. Needle placement at this level is used for epidural steroid delivery in lumbosacral radicular pain and for caudal epidural anesthesia, where a shallow posterior approach helps avoid periosteal contact and reduces the chance of subcutaneous injection. The fixed posterior viewpoint keeps attention on what the operator palpates, and the relationship between the needle and the hiatus clarifies why a too-lateral entry risks contacting the cornua or drifting away from the canal. Pain medicine and anesthesiology educators can drop this illustration directly into modules on caudal epidural technique, sacral surface anatomy, and complications such as intravascular injection via the sacral epidural venous plexus or failed epidural spread from a small or closed hiatus. Medical publishers will also find it well-suited for procedure atlases, informed-consent handouts, and board-style questions focused on posterior sacral landmarks. Anatomical accuracy verified by SciePro's Medical Advisory Board.