Web
Analytics
Real Time Analytics
Visit us at:

Pectoralis Major Origin, Insertion, Actions, Innervation

(Last Updated On: August 10, 2018)
Pectoralis Major Origin, Insertion, Action, Innervation

Muscle Anatomy of the Pectoralis Major Clavicular Head

Origin: Anterior surface of the medial half of the clavicle
Insertion: Lateral lip of the bicipital groove of the humerus and anterior lip of the deltoid tuberosity
Actions: Flexion, adduction and internal rotation of the arm at shoulder,
Innervation: Medial pectoral nerve (C8, T1 - from medial cord) and lateral pectoral nerve (C5, 6, 7 - from lateral cord)
Blood Supply: Pectoral branches from the thoraco-acromial artery

Muscle Anatomy: Pectoralis Major Clavicular Head Actions

Primary Actions of the Pectoralis Major Clavicular Head

1.  Flexion of the arm at the shoulder

  Agonists:

  • Deltoid (anterior)
  • Biceps brachii
  • Coracobrachialis

  Antagonists:

  • Deltoid (posterior)
  • Triceps brachii (long head)
  • Latissimus dorsi
  • Pectoralis major (sternal head)
  • Teres major

2. Adduction of the arm at the shoulder

Agonists:

  • Latissimus dorsi
  • Teres major
  • Pectoralis major (sternal head)
  • Triceps brachii (long head)

Antagonist:

  • Deltoid (middle part)
  • Supraspinatus

3. Internal rotation of the arm at the shoulder

  Agonists:

  • Latissimus dorsi
  • Subscapularis
  • Deltoid
  • Pectoralis major (sternal head)
  • Teres major

  Antagonists:

  • Infraspinatus
  • Teres minor
  • Deltoid (posterior part)

Muscle Anatomy of the Pectoralis Major Sternal Head

Origin: Lateral aspects of the manubrium and body of the sternum, the upper six costal cartilages and the aponeurosis of external abdominal oblique
Insertion: Lateral lip of the bicipital groove of the humerus and anterior lip of the deltoid tuberosity
Actions: Adduction, internal rotation and extension of the arm at shoulder
Innervation: Medial pectoral nerve (C8, T1 - from medial cord) and lateral pectoral nerve (C5, C6, C7 - from lateral cord)
Blood Supply: Pectoral branches from the thoraco-acromial artery

Muscle Anatomy: Pectoralis Major Sternal Head Actions

Primary Actions of the Pectoralis Major Sternal Head

1.  Adduction of the arm at the shoulder

  Agonists:

  • Latissimus dorsi
  • Teres major
  • Pectoralis major (clavicular head)
  • Triceps brachii (long head)

  Antagonists:

  • Deltoid (middle)
  • Supraspinatus

2. Internal rotation of the arm at the shoulder

  Agonists:

  • Latissimus dorsi
  • Subscapularis
  • Deltoid (anterior)
  • Pectoralis major (clavicular head)
  • Teres major

  Antagonists:

  • Infraspinatus
  • Teres minor
  • Deltoid (posterior part)

3. Extension of the arm at the shoulder

Agonists:

  • Latissimus dorsi
  • Deltoid (posterior)
  • Triceps brachii (long head)
  • Teres major

Antagonist:

  • Deltoid (anterior part)
  • Biceps brachii
  • Coracobrachialis
  • Pectoralis major (clavicular head)

Information about cause and effect of Pectoralis Major pain:

Pectoralis Major Pain and Symptoms

Recommended Anatomy Books:

Anatomy Coloring Book

The Anatomy Coloring Book is one of the best study and reference books for beginning anatomy students. The diagrams are clearly labeled and allow you to see the relationship and placement of the various structures of the body. You will also be surprised how the act of coloring will help with recall. But this is not just a beginners book, it is also great for practitioners and therapists to have on hand to use with clients and patients to use as a visual reference.

Human Muscle Anatomy

The Trail Guide To The Body is another excellent book to help you learn the musculature of the human body. Though the book is geared toward massage therapists and physical therapist assistants, the book with its illustrations and text helps anyone gain a thorough understanding of the human musculoskeletal system and movement. I highly recommend this book for anyone studying anatomy and believe that MTs, PTAs, and teachers of body movements should have this book in their possession. I also highly recommend this book for the lay person who wants to gain understanding of the muscle, skeletal system and how our bodies move. This book will not disappoint!

Basic Clinical Massage Therapy

Out of the scores of books in my office Basic Clinical Massage Therapy is by far the most referenced book in my library. The musculoskeletal system is overlaid on human models allowing you to learn the precise location, origin and insertions of each muscle. The models are pictured in various poses throughout the book which also helps you visualize muscles in motion and their actions relationship with the skeletal structure and other muscles. Though it is written for massage therapists, it is an excellent book for anyone who wants to learn about the muscular system. MT's will benefit from recommended treatments for each muscle.

Muscle Anatomy Flashcards

Musculoskeletal Anatomy Flashcards Are you a student or professional therapist who needs to brush up on the musculoskeletal system? Dr. Joseph E. Muscolino DC has developed a comprehensive set of flashcards that will help develop a mind's picture of exactly where the muscles lie under the skin. A highly recommended study aid for students. Great for non students who want an easy comprehensive anatomy guide.

Leave a Comment