Extensors of the Shoulder

Question 1

Pectoralis Major

Answer 1

O: medial half of the anterior surface of the clavicle and the lateral aspect of the body of the sternum
I: into the lateral lip of the intertubercular groove of the humerus
N: Medial C8 & Lateral C5, C6, C7 pectoral nerves
A: medial rotation of the adduction of the shoulder joint
Clavicular part - shoulder flexion
Sternal part - shoulder extension from a flexed position