Subcostal muscles

Subcostalis muscle
Details
Origin	inner surface of one rib
Insertion	inner surface of the second or third rib below, near its angle
Nerve	intercostal nerves
Actions	depresses ribs.
Identifiers
Latin	musculus subcostalis
Dorlands /Elsevier	m_22/12551003
TA	A04.4.01.015
FMA	71315
Anatomical terms of muscle []

The Subcostales (singular: subcostalis) (Infracostales) consist of muscular and aponeurotic fasciculi, which are usually well-developed only in the lower part of the thorax; 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.

The function of this muscle is unknown, but it is part of the innermost intercostal muscle group along with the transversus thoracis muscle which is known to be a synergist in aiding the internal intercostal muscles with forced exhalation.

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)

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