Latin arcus costalis TA A02.3.04.006 | Dorlands/Elsevier a_58/12150537 FMA 7569 | |
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The costal margin is the lower edge of the chest (thorax) formed by the bottom edge of the rib cage.
Sometimes referred to as the costal arch, it is the medial margin formed by the false ribs and one true rib—specifically, from the seventh rib to the tenth rib.
References
Costal margin Wikipedia(Text) CC BY-SA