Spine

Illustration of the spine

The spine (backbone) is composed of 33 interlocking bones called vertebrae that are separated by soft, compressible discs and supported by many different ligaments and muscles. It is divided into five segments: cervical (neck), thoracic (upper and middle back), lumbar (lower back), sacrum (pelvis), and coccyx (tailbone). In each segment, the vertebrae are numbered from top to bottom. For example, a C3 is the third vertebra in the neck area, while a T6 is the sixth vertebra in the thoracic area.

The vertebrae in the spine normally form three curves. These curves allow the spine to absorb shock as you move.

ByHealthwise Staff
Primary Medical Reviewer William H. Blahd, Jr., MD, FACEP - Emergency Medicine
Donald Sproule, MDCM, CCFP - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
Robert B. Keller, MD - Orthopedics

Current as ofNovember 29, 2017

Is it an emergency?

If you or someone in your care has chest pains, difficulty breathing, or severe bleeding, it could be a life-threatening emergency. Call 9-1-1 or the local emergency number immediately.
If you are concerned about a possible poisoning or exposure to a toxic substance, call Poison Control now at 1-800-567-8911.

Thanks to our partners and endorsers: