Upper Arm Muscles (origin, insertion, action)

Action of Deltoid

Abduction at shoulder

Action of Supraspinatus

Abduction at shoulder

Origin of Deltoid (Middle head)

Acromion process and spine of scapula

Origin of Deltoid (Anterior head)

Anterior surface of the lateral clavicle

Insertion of Deltoid

Deltoid tuberosity of humerous

Action of Latissimus Dorsi

Extension, adduction, and medial rotation at shoulder

Action of Teres Major

Extension, adduction, and medial rotation at shoulder

Action of Pectoralis Major

Flexion, adduction and medial rotation at shoulder

Insertion of Latissimus Dorsi

Floor of intertubercular groove of humerous

Insertion of Infraspinatus

Greater tubercle of humerous

Insertion of Supraspinatus

Greater tubercle of humerous

Origin of Teres Major

Inferior angle of scapula

Origin of Infraspinatus

Infraspinous fossa of scapula

Origin of Teres Minor

Lateral border of scapula

Insertion of Pectoralis Major

Lateral lip of intertubercular groove of humerous and crest of greater tubercle of humerous

Action of Infraspinatus

Lateral rotation at shoulder

Action of Teres Minor

Lateral rotation at shoulder

Insertion of Subscapularis

Lesser tubercle of humerous

Origin of Pectoralis Major (clavicular head)

Medial half of clavicle

Action of Subscapularis

Medial rotation at shoulder

Insertion of Teres Minor

Passes laterally to reach the greater tubercle of humerous

Insertion of Teres Major

Passes medially to reach the medial lip of intertubercular groove of humerous

Origin of Deltoid (Posterior head)

Spine of scapula

Origin of Latissimus Dorsi

Spinous processes of inferior thoracic and all lumbar vertebrae, ribs 8-12 and thoracolumbar fascia

Origin of Pectoralis Major (sternal head)

Sternum, upper costal cartilages (1-6) and the aponeurosis of External Obliques

Origin of Subscapularis

Subscapular fossa of scapula

Origin of Supraspinatus

Supraspinous fossa of scapula