Also called: breastbone
The sternum, or breastbone, is the flat bone in the middle of the front of the chest. It has three parts: the manubrium, body and xiphoid process. It articulates with the clavicles and the upper seven pairs of costal cartilages and protects the heart and great vessels.
| Type | Flat bone. |
|---|---|
| Location | Anterior midline of the thorax. |
| Landmarks | Manubrium, jugular notch, sternal angle, body, xiphoid process, clavicular and costal notches. |
| Articulations | Clavicles (sternoclavicular joints) and costal cartilages of ribs 1 to 7. |
| Muscle attachments | Pectoralis major, sternocleidomastoid, sternohyoid, sternothyroid, rectus abdominis, diaphragm. |
3D model: BodyParts3D (CC BY 4.0), adult male reference anatomy. Highlighted structure shown with nearby bones for context.
The sternal angle, at the junction of manubrium and body, lies at the level of the second costal cartilage and the T4-T5 intervertebral disc, an important clinical landmark.
The manubrium, body and xiphoid process.
It marks the second rib, the level of the tracheal bifurcation and the start of the aortic arch.
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