Pectoralis minor muscle

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Pectoralis minor


Deep muscles of the chest and front of the arm, with the boundaries of the axilla. (Pectoralis minor visible near center.)
Latin	musculus pectoralis minor
Gray's	subject #122 438
Origin:	3rd to 5th ribs, near their costal cartilages
Insertion:	medial border and superior surface of the coracoid process of the scapula
Blood:	Pectoral branch of the thoracoacromial trunk
Nerve:	Medial pectoral nerves (C8, T1)
Action:	It stabilizes the scapula by drawing it inferiorly and anteriorly against the thoracic wall.
Dorlands/Elsevier	m_22/12550138

The Pectoralis minor is a thin, triangular muscle, situated at the upper part of the thorax, beneath the Pectoralis major.

It arises from the upper margins and outer surfaces of the third, fourth, and fifth ribs, near their cartilage and from the aponeuroses covering the Intercostalis.

The fibers pass upward and lateralward and converge to form a flat tendon, which is inserted into the medial border and upper surface of the coracoid process of the scapula.

The pectoralis minor muscle is covered anteriorly (superficially) by the clavipectoral fascia. The medial pectoral nerve pierces the pectoralis minor and the clavipectoral fascia.

[edit] Variations

Origin from second, third and fourth or fifth ribs. The tendon of insertion may extend over the coracoid process to the greater tubercle. May be split into several parts. Absence rare.

[edit] Additional images

The veins of the right axilla, viewed from in front.

[edit] External links

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

Muscles of the Head — Neck — Trunk — Upper limb — Lower limb— LIST OF ALL MUSCLES