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URL of this page: //medlineplus.gov/ency/imagepages/19464.htm
Sacrum
Overview
The sacrum is a shield-shaped bony structure that is located at the base of the lumbar vertebrae and that is connected to the pelvis. The sacrum forms the posterior pelvic wall and strengthens and stabilizes the pelvis. Joined at the very end of the sacrum are two to four tiny, partially fused vertebrae known as the coccyx or "tail bone". The coccyx provides slight support for the pelvic organs but actually is a bone of little use.
Review Date 4/1/2025
Updated by: Jason Levy, MD, FSIR, Northside Radiology Associates, Atlanta, GA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
