Muscle
Pectoralis minor
Pulls the scapula toward the front of the chest
High-yield
Pectoralis minor is the landmark used to describe the three parts of the axillary artery: before, behind and beyond the muscle.
Overview
Deep to pectoralis major, this smaller muscle links the upper ribs to the coracoid. It helps position the scapula forward and downward against the thorax.
Reference facts
- Origin
- Usually ribs 3–5 near their costal cartilages
- Insertion
- Medial border and superior surface of the scapular coracoid process
- Action
- Draws the scapula forward and downward; with it fixed, can assist rib elevation during forced inspiration
- Innervation
- Mainly medial pectoral nerve, C8–T1; additional pectoral connections can occur
- Blood supply
- Pectoral branches of the thoracoacromial artery
Clinical correlation
Nerves and vessels passing beneath pectoralis minor can be compressed in pectoralis minor syndrome. Symptoms may overlap with other shoulder and upper-limb conditions, so the anatomical location alone is not a diagnosis.
Frequently asked questions
What does the pectoralis minor do?
Draws the scapula forward and downward; with it fixed, can assist rib elevation during forced inspiration.
What nerve innervates the pectoralis minor?
Mainly medial pectoral nerve, C8–T1; additional pectoral connections can occur.
Where does the pectoralis minor attach?
Origin: Usually ribs 3–5 near their costal cartilages. Insertion: Medial border and superior surface of the scapular coracoid process.
What is the blood supply of the pectoralis minor?
The pectoralis minor is supplied by the pectoral branches of the thoracoacromial artery.