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The spine is made of bones (vertebrae) separated by soft cushions (intervertebral disks).
Review Date 11/16/2025
Updated by: C. Benjamin Ma, MD, Chair, Department of Orthopaedic Surgery, Dr. Peter and Sophie Pappas Endowed Chair, V-nee Yeh Endowed Professor of Orthopaedic Surgery, University of California, San Francisco, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.