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 (: thoraces or thoraxes) or chest is a part of the anatomy of 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 di ...
; each originates from the inner surface of one
rib, 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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