Sternum

What it means

The sternum is the medical name for the breastbone — the flat, slightly elongated bone that runs down the middle of the front of your chest. Most of your ribs connect to it through cartilage, and the collarbones attach near its top. Together with the ribs it forms the protective cage around the heart and the large blood vessels behind it. You can feel it as the firm strip down the centre of your chest.

Why it appears on a CT, MRI or X-ray report

Radiologists describe the sternum when checking for fractures (usually from a direct blow, such as a steering wheel or seatbelt in a car accident), alignment, bone density, the joints where it meets the ribs and collarbones, and any spots within the bone. It is also a landmark near the heart, so reports may mention it when describing structures just behind it or noting that someone has had previous chest surgery, where the bone is split and wired back together.

What it usually means

Most reports name the sternum simply to set the location of a finding, and the word on its own carries no alarm. Reassuring phrases include intact and no fracture. If you have had heart or chest surgery, the report may describe wires or a healed split down the middle, which is completely expected. Common, harmless mentions include normal joints with the ribs or mild age-related changes. The descriptors that deserve attention are fracture (often after a significant chest impact, which prompts a check of the heart and lungs nearby), or a lesion within the bone. As with any bone, the name is just an address — the real meaning lives in the descriptor beside it and how it fits the rest of the chest findings.

When to follow up

The name alone needs no action. Ask your doctor about any descriptor attached to it. A sternum fracture, because it usually follows a strong impact, deserves prompt assessment to check the heart and lungs behind it. Seek urgent care after a chest injury if you have severe central chest pain, shortness of breath, an irregular heartbeat, or pain that spreads to the arm or jaw.

A plain-language way to picture it

Picture the central clasp of a suit of armour — the flat plate down the middle of the chest that the side panels (the ribs) all hook onto. That central plate is your breastbone. It is the firm ridge you press on if you ever learn CPR, because it sits directly over the heart and lets pressure reach it through the chest wall.