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see ribrib,
one of the slender, elongated, curved bones that compose the chest cage in higher vertebrates. Ribs occur in pairs, and are found in most vertebrates; however, in some lower vertebrates, including fishes, they run along the entire length of the backbone.
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the complex of skeletal elements in terrestrial vertebrates and man that unite, along the midline of the body, the ventral ends of the true ribs and parts of the pectoral girdle and to which the sternal muscles are attached.

The sternum is a derivative of the ribs and first appeared in terrestrial vertebrates when a strengthening of support for the pectoral girdle was required in connection with the progressive evolution of the forelimbs. In amphibians and reptiles the sternum is usually cartilaginous; in the latter, only a few ribs are attached, forming the thorax. In birds the sternum is osseous; in flying birds there is a median process, the keel, to which the powerful pectoral muscles are attached. In mammals the sternum consists of three sections: the manubrium, the corpus sterni, and the xiphoid process. In man the sternum, or breastbone, is an unpaired flat bone that forms the middle part of the anterior wall of the thorax.


The bone, cartilage, or series of bony or cartilaginous segments in the median line of the anteroventral part of the body of vertebrates above fishes, connecting with the ribs or pectoral girdle.


1. (in man) a long flat vertical bone, situated in front of the thorax, to which are attached the collarbone and the first seven pairs of ribs
2. the corresponding part in many other vertebrates
3. a cuticular plate covering the ventral surface of a body segment of an arthropod
References in periodicals archive ?
Although chondrosarcomas are considered the most common primary malignancy of the chest wall and sternum, it is nevertheless a rare lesion as reported in the literature.
The sternum was 40mm wide and 11mm deep and is naturally a strong and dense bone so the force required, even with a sharp knife, would be severe.
Through a series of maneuvers, a customized curved stainless steel bar is positioned behind the sternum but on top of the chest wall, using it as a base of support.
BioCell Collagen II[R] is the worldwide leading supplier of Sternum Collagen Type II.
Create space first by pressing your hips back and pulling your sternum forward.
There are anatomical confusions, too, photographs in which a model's chin and upper arm read like a third and fourth breast or in which a torso is so twisted that the faint line running from navel to sternum looks like a butt crack.
Other skeletal abnormalities include a sternum (breastbone) that is either protruding or indented, curvature of the spine (scoliosis), and flat feet.
A 51-year-old, who was driving a Ford Sierra, suffered a broken arm, rib and sternum in the accident on the B439 at Binton shortly after 9am.
The closest comparison that comes to mind is being the unwitting intermediary of an elbow to the sternum and a simultaneous cuff on the back of the head.
It is believed Guest suffered an injury to his sternum and he was immediately taken to hospital after appearing to be in some distress.
I was caring for a man who had developed an infection in his sternum after open-heart surgery and had undergone a sternectomy (removal of the sternum).
Repeatedly pushing down on the victim's chest compresses the heart between the sternum (breastbone) and the backbone.