Anterior Thoracic Muscles

Subclavius

Pectoralis minor

Serratus anterior

Posterior Thoracic Muscles

1. Trapezius
2. Levator Scapulae
3. Rhomboid major
4. Rhomboid minor

Subclavius

Origin: First Rib

Insertion: Clavicle

Action:Depresses and moves clavicle anteriorly and helps stabilize pectoral girdle

Innervation: Subclavian nerve

Pectoralis Minor

Origin: 2-5th rib

Insertion: Coracoid proces of scapula

Action: Abducts scapula & rotates downward;elevates 3-5th rib during forced inhalation when scapula is fixed (changing origin/insertion.

Innervation: Medial pectoral nerves

Serratus Anterior

Origin: Superior eight or nine ribs.

Insertion: Vertebral border and inferior angle of scapula.

Action: Abducts/Rotates scapula upward; elevates ribs when scapula is stabilized; boxers muscle; abduction/protraction ...punch/hug

Innervation: Long thoracic nerve

Trapezius

Origin: Superior Nuchal line (lateral to E.O.P) of occipital bone, ligamentum Nuchae, and spines of 7th Cervical and all Thoracic Vertebra.

Insertion: Clavicle, Acromion & Spine of Scapula

Action: Superior fibers=elevate scapula , Middle fibers= Adduct Scapula, Inferior fibers= depress scapula, Superior & Inferior fibers: rotate scapula up & Stabilizes.

Innervation: Accessory XI nerve and cervical spinal nerves C3-C5

Levator Scapula

Origin: Superior 4-5 cervical vertebrae

Insertion: Superior vertebral border of scapula

Action: Elevates scapula and rotates it downward

Innervation: Dorsal scapular nerve and cervical spinal nerves C3-C5

Rhomboid Major

Origin: Spines of 2nd-5th Thoracic vertebrae

Insertion: Vertebral border of scapula inferior to spine.

Action: Elevates and Adducts scapula & rotates it downward; stabilizes scapula

Innervation: Dorsal scapular nerves

Rhomboid Minor

Origin: Spines of 7th cervical and 1st thoracic vertebrae.

Insertion: Vertebral border of scapula superior to spine.

Action: Elevates and adducts scapula, rotates downward; stabilizes scapula.

Innervation: Dorsal scapular nerve