The pectoralis major muscle is a thick, fan-shaped, situated anteriorly at the chest of the human body. It makes up the bulk of the chest muscles in the male and lies under the breast in case of the female. Underneath the pectoralis major is the pectoralis minor muscle, a thin, triangular muscle.
In sports as well as bodybuilding, the pectoral muscles may be referred to as “pecs”, “pectoral muscle” or “chest muscle”.
Attachments of the Pectoralis Major Muscle
Origin:
Clavicular head: medial half of the clavicle.Sternal head: sternum, upper costal cartilages (1-6), and aponeurosis of the external oblique
Sternal head: sternum, upper costal cartilages (1-6), and aponeurosis of the external oblique
Insertion:
Lateral lip of the bicipital (intertubercular) groove of the humerus.
Crest of the greater tubercle of the humerus. Coracoid process of the scapula
Function of the Pectoralis Major Muscle
Draws scapula anteriorly and inferiorly;
Adducts and medially rotates humerus;
Acting alone: clavicular head flexes humerus and sternocostal head extends it
Nerve Supply of the Pectoralis Major Muscle
The medial pectoral nerve to the sternal head.
The lateral pectoral nerve to the clavicular head.
Upper Extremity Muscle Atlas
- Abductor Pollicis Longus
- Abductor Digiti Minimi
- Abductor Pollicis Brevis
- Adductor Pollicis
- Anconeus
- Biceps Brachii
- Brachioradialis
- Brachialis
- Coracobrachialis
- Deltoid
- Extensor Carpi Radialis Longus
- Extensor Carpi Radialis Brevis
- Extensor Carpi Ulnaris
- Extensor Digitorum
- Extensor Digiti Minimi
- Extensor Indicis
- Extensor Pollicis Longus
- Extensor Pollicis Brevis
- Flexor Carpi Radialis
- Flexor Carpi Ulnaris
- Flexor Digitorum Profundus
- Flexor Digitorum Superficialis
- Flexor Digiti Minimi Brevis
- Flexor Pollicis Brevis
- Flexor Pollicis Longus
- Infraspinatus
- Interosseous Muscles, Dorsal
- Interosseous Muscles, Palmar
- Levator Scapulae
- Latissimus Dorsi
- Opponens Digiti Minimi
- Opponens Pollicis
- Pectoralis Major
- Pectoralis Minor
- Palmaris Longus
- Pronator Quadratus
- Pronator Teres
- Rhomboid Major and Minor
- Subscapularis
- Supinator
- Serratus Anterior
- Supraspinatus
- Trapezius
- Triceps Brachii
- Teres Major
- Teres Minor