Chest · Flat bone
Sternum (Breastbone)
The sternum, or breastbone, is the flat bone in the centre of the chest. The ribs attach to it, and it protects the heart and lungs. It is the landmark used for chest compressions in CPR.
What it is
The sternum is a long, flat bone in the middle of the front of the chest, made of three parts. Most of the ribs connect to it through cartilage.
Where it is
The centre of the front of the chest, from the base of the neck down to the upper abdomen.
What it does
Protects the heart, lungs and major blood vessels, and provides an anchor for the ribs, helping form the protective cage around the chest organs.
Connections
Joints and connections
- Joints with the clavicles
- Joints with the ribs (via cartilage)
When things go wrong
Common injuries and conditions
- Sternum fracture (usually from major chest trauma, e.g. a car crash)
- Costochondritis (painful inflammation where ribs meet the sternum)
Education and reference only. This explains the anatomy in plain terms; it is not a diagnosis. A severe injury, a visibly deformed limb, or the inability to move or bear weight needs urgent assessment — call 999 or go to A&E for a serious injury.
Did you know?
An interesting fact
The lower tip of the sternum (the xiphoid process) is the landmark clinicians use to position their hands correctly for CPR chest compressions.
Answers
Sternum: frequently asked questions
What is the breastbone?
The breastbone (sternum) is the flat bone in the centre of the chest to which the ribs attach. It protects the heart and lungs.
What causes pain over the breastbone?
Common causes include costochondritis (inflammation of rib cartilage) or muscle strain, but chest pain can also signal serious problems — sudden or severe central chest pain needs urgent assessment (call 999).
Explore the chest
Related bones
Sources
Where this is drawn from
- NHS — Anatomy and body systems
- Gray's Anatomy for Students (Drake, Vogl, Mitchell)
- TeachMeAnatomy — skeletal system
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