082 The Origin, Insertion, and Action of Pectoralis Major

This video by Leslie Samuel explores the pectoralis major muscle, detailing its structure, origins, insertion points, and actions. The muscle is divided into the clavicular and sternocostal portions, each with distinct origins. The insertion is at the humerus, specifically the crest of the greater tubercle. The video explains how the muscle's contraction leads to various arm movements, including flexion, extension, adduction, and medial rotation. The tutorial concludes with a review of these key points, emphasizing the muscle's role in arm movement.

What are the two portions of the pectoralis major muscle?

Describe the origin of the clavicular head of the pectoralis major.

What is the origin of the sternocostal portion of the pectoralis major?

Where does the pectoralis major insert on the humerus?

What action does the clavicular head of the pectoralis major perform when it contracts?

Explain the overall action of the pectoralis major muscle.

What is the role of the pectoralis major in arm movement?