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
