Muscles of the Thoracic Wall

Subclavius: Origin, insertion, innervation, insertion

Origin: Junction between the first rib and its costal cartilage Insertion: Groove on the inferior surface of the middle third of clavicle Innervation: Nerve of subclavius (C5-C6) Function: Pulls tip of shoulder down; pulls clavicle medially in order to stabilize the sternoclavicular joint.

Pectoralis major: Origin, insertion, innervation, insertion

Origin: Clavicular head: anterior suface of medial half of clavicle Insertion: Lateral lip of intertubercular sulcus of humerus Innervation: Medial and Lateral pectoral nerves Function: Flexion, adduction and medial rotation of shoulder joint

Serratus Anterior: Origin, insertion, innervation, insertion

Origin: Lateral surface of upper 8-9 ribs and deep fascia covering related intercostal spaces Insertion: Costal surfaces of medial border of scapula Innervation: Long thoracic nerve (C5-C7) Function: Protraction and rotation of scapula; keeps medial border and inferior angle of scapula opposed to thoracic wall

Pectoralis minor: Origin, insertion, innervation, insertion

Origin: Sternocostal head: anterior surface of sternum, first 7 costal cartilages/adjacent ribs Insertion: Medial border of caracoid process of scapula Innervation: Medial pectoral nerve Function: Pulls tip of shoulder down; protracts scapula

Name the 4 pectoral muscles.

Pectoralis Major, Pectoralis Minor, Serratus anterior, Subclavius