manubrium

vertebrate anatomy

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Last updated

June 30, 2026

Quick Summary

The manubrium is the uppermost segment of the sternum in humans and many other mammals. The sternum, or breastbone, is a bone in the center of the chest that supports the collarbones and ribs. In mammals, the sternum is divided into three parts: the manubrium, the mesosternum, and the xiphisternum. The manubrium specifically articulates with the clavicles and the first pair of ribs. It is roughly trapezoidal in shape and has indentations where these bones connect. The sternum's evolutionary origin is not entirely clear, but it is present in most four-limbed vertebrates.12

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sternum
…anterior to posterior: (1) the manubrium, which articulates with the clavicles and first ribs; (2) the mesosternum, often divided into a series of segments, the sternebrae, to which the remaining true ribs are attached; and (3) the posterior segment, called the xiphisternum. In humans the sternum is elongated and flat;…
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…anterior to posterior: (1) the manubrium, which articulates with the clavicles and first ribs; (2) the mesosternum, often divided into a series of segments, the sternebrae, to which the remaining true ribs are attached; and (3) the posterior segment, called the xiphisternum. In humans the sternum is elongated and flat;…
Read More