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URL of this page: //medlineplus.gov/ency/article/002366.htm
Flat bones
Flat bones are made up of a layer of spongy bone between two thin layers of compact bone. They have a flat shape, not rounded. Examples include the skull and rib bones. Flat bones have marrow, but they do not have a bone marrow cavity.
Fillmore EP. Thoracic wall and breast. In: Standring S, Tubbs RS, Anand N, et al, eds. Gray's Anatomy: The Anatomical Basis of Clinical Practice. 43rd ed. Philadelphia, PA: Elsevier; 2026:chap 56.
Standring S. Skull. In: Standring S, Tubbs RS, Anand N, et al, eds. Gray's Anatomy: The Anatomical Basis of Clinical Practice. 43rd ed. Philadelphia, PA: Elsevier; 2026:chap 36.
Review Date 10/1/2025
Updated by: Linda J. Vorvick, MD, Clinical Professor Emeritus, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
