Pectoralis Minor: Origin, Insertion, Nerve Supply & Action

Pectoralis Minor: The pectoralis minor muscle is a thin, triangular muscle, situated at the upper part of the chest and beneath the pectoralis major in the human body. The Pectoralis Minor is the smallest muscle of the two pectoral (chest) muscles. It works together with Serratus anterior muscle which protracts and rotates the scapula upwards.

When the two muscle works together, pure protraction (without rotation) is produced.

Attachments of the Pectoralis Minor Muscle

Origin:
The outer surface of ribs 3-5
Insertion:
Coracoid process of the scapula

The function of the Pectoralis Minor Muscle
Scapular protraction
Rotation of the scapula downwards

Nerve Supply of the Pectoralis Minor Muscle
Medial pectoral nerve