The Subcostales (singular: subcostalis) (Infracostales) consist of muscular and
aponeurotic fasciculi, which are usually well-developed only in the lower part of the
thorax
The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the ...
; each originates from the inner surface of one
rib
In vertebrate anatomy, ribs ( la, costae) are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the ch ...
, and is inserted into the inner surface of the second or third rib below, near its angle.
Their fibers run in the same direction as those of the
Intercostales interni.
Depresses the ribs to assist in expiration.
References
Muscles of the torso
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