Shoulder, Upper arm muscles Flashcards
Origin of Deltoid
Lateral one-third of clavicle, acromion, and spine of the scapula
Insertion of Deltoid
Deltoid tuberosity
All fibers of Deltoid perform this action
Abduct the shoulder (glenohumeral joint)
Anterior fibers of Deltoid perform these 3 actions
- Flex the shoulder - Medially rotate the shoulder - Horizontally abduct the shoulder
Origin of Teres Major
Inferior angle and lower one-third of lateral border of scapula
Insertion of Teres Major
Crest of the lesser tubercle of the humerus
The 3 actions of Teres Major
- Extend the shoulder (G/H joint) - Adduct the shoulder (G/H joint) -Medially rotate the shoulder (GH joint)
Origin of Supraspinatus
Supraspinous fossa of the scapula
Insertion of Supraspinatus
Greater tubercle of the humerus
The 2 actions of the Supraspinatus
- Abduct the shoulder (GH joint) - Stabilize the head of the humerus in glenoid cavity
Origin of Infraspinatus
Infraspinous fossa of the scapula
Insertion of Infraspinatus
Greater tubercle of the humerus
The 3 actions of Infraspinatus
- Laterally rotate the shoulder (GH joint) - Adduct the shoulder (GH joint) -Stabilize the head of the humerus in glenoid cavity
Origin of Teres Minor
Upper two-thirds of lateral border of the scapula
Insertion of Teres Minor
Greater tubercle of the humerus
The 3 actions of Teres Minor
- Laterally rotate the shoulder (GH joint) - Adduct the shoulder (GH joint) - Stabilize the head of the humerus in glenoid cavity
Origin of Subscapularis
subscapular fossa of the scapula
Insertion of Subscapularis
Lesser tubercle of the humerus
The 2 actions of Subscapularis
- Medially rotate the shoulder (GH joint) -Stabilize the head of the humerus in glenoid cavity
Origin of Biceps Brachii
Short head: Coracoid process of the scapula Long head: Supraglenoid tubercle of scapula
Insertion of Biceps Brachii
Tuberosity of the radius and aponeurosis of biceps brachii
The 3 actions of Biceps Brachii
- Flex the elbow (humeroulnar joint) -Supinate the forearm (radioulnar joints) - Flex the shoulder (GH joint)
Origin of Triceps Brachii
Long head: Infraglenoid tubercle of the scapula Lateral head: Posterior surface of proximal half of the humerus Medial head: Posterior surface of distal half of the humerus
Insertion of Triceps Brachii
Olecranon process of the ulna

















