Pectoral Muscles: Origin, Insertion, Innervation, and Action

Subclavius: Action

1. Anchor clavicle 2. Protect deeper neurovasculature 3. Prevent dislocation

Serratus Anterior: Action

1. Stabilize scapula - hold against ribs 2. Rotates scapula superiorly - shrug, protract, lift arm >90 3. Protect scapula (boxers muscle)

Pectoralis Minor: Action

1. Stabilize the scapula 2. Draw scapula anteriorly - stretching, reaching out 3. Elevate the ribs during inspiration

Pectoralis Minor: Insertion

Coracoid process (extension of scapula)

Serratus Anterior: Innervation

Long thoracic nerve

Subclavius: Innervation

Nerve to subclavius

Subclavius: Origin

Rib 1 (between bone and cartilage)

Serratus Anterior: Origin

Rib 1-8 (lateral border)

Pectoralis Major: Insertion

intertubercular sulcus/groove

Pectoralis Major: Action

1. Powerful adduction - adding arm back to body 2. Medial rotation - flex/roll arm in 3. Flexion- clavicular head (breaststroke muscle)

Subclavius: Insertion

Inferior surface of clavicle

Pectoralis Minor: Origin

Ribs 3,4,5 (b/w rib and cartilage)

Pectoralis Major: Innervation

Medial and Lateral pectoral nerves

Serratus Anterior: Insertion

Medial border of scapula

Pectoralis Major: Origin

Medial half of clavicle, along the sternum inferiorly

Pectoralis Minor: Innervation

Medial pectoral nerve