Anterior Axio-Appendicular Muscles Flashcards
Where does the pectoralis major insert?
Lateral lip of the intertubercular groove of the humerus
What is the origin of the pectoralis major?
The clavicular head originates on the anterior surface of the the medial half of the clavicle.
The sternocostal head originates on the anterior surface of the sternum, superior six costal cartilages, and aponeurosis of the external oblique muscle.
What is the innervation of the pectoralis major?
Lateral and medial pectoral nerves, clavicular head (C5, C6) and sternocostal head (C7, C8, T1)
What is the action of the pectoralis major?
Alone, clavicular head flexes shoulder joint and sternocostal head extends it from the flexed position.
In conjunction with other muscles, adducts and medially rotates shoulder joint, draws scapula anteriorly and inferiorly.
What is the origin of the pectoralis minor?
3rd-5th ribs near their costal cartilages
Where does the pectoralis minor insert?
Medial border and superior surface of coracoid process of scapula
What is the innervation of the pectoralis minor?
Medial pectoral nerve (C8, T1)
What action does the pectoralis minor perform?
Stabilizes scapula by drawing inferiorly and anteriorly against thoracic wall
Where does the subclavius originate?
Junction of 1st rib and its costal cartilage
Where does the subclavius insert?
Inferior surface of middle third of clavicle
What is the innervation of the subclavius?
Subclavian nerve (C5, C6)
What action does the subclavius perform?
Anchors and depresses clavicle
What is the origin of the serratus anterior?
External surfaces of lateral parts of 1st-8th ribs
Where does the serratus anterior insert?
Anterior surface of medial border of scapula
What is the innervation of the serratus anterior?
Long thoracic nerve (C5, C6, C7)
