A Female's Sacrum

Description

Centered within the pelvic ring, the female sacrum appears as a triangular, fused segment of the vertebral column, wedged between the right and left hip bones at the sacroiliac joints. Superiorly it articulates with L5 at the lumbosacral junction, while inferiorly it tapers to meet the coccyx. The sacral promontory defines the posterior margin of the pelvic inlet, and the broad sacral ala flare laterally to form the posterior part of the pelvic brim. Blue highlighting isolates the pelvic girdle against the remainder of the standing skeleton, keeping spatial relationships to the iliac crests, acetabula, and proximal femora easy to read. Sex-linked pelvic morphology matters here because sacral curvature and the width of the alae influence obstetric dimensions, including the anteroposterior diameter at the inlet and the contour of the posterior pelvis during labor. Sacroiliac joint dysfunction and inflammatory sacroiliitis often localize pain near the posterior superior iliac spine, and this bony orientation helps explain why symptoms can refer into the buttock and posterior thigh. For procedures, the sacral hiatus and dorsal surface landmarks guide caudal epidural access, while the relationship between the sacrum and coccyx frames common fracture patterns after low-energy falls. Use this asset in pelvic anatomy and osteology modules, radiology teaching sets that pair skeletal anatomy with pelvic CT or plain films, and obstetrics and gynecology texts discussing pelvic inlet and outlet configuration in a female pelvis. It also suits orthopedic and pain-medicine education when describing sacroiliac joint anatomy and posterior pelvic landmarks. Anatomical accuracy verified by SciePro's Medical Advisory Board.