Supinator

origin

lateral humerus&ulna

insertion

anterior radius

action

supination

Anconeus

lateral epicondlye-> lateral ulna

extension

infraglenoid tubercle&posterior humerus-> olecranon process

extend elbow

anterior lower humerus-> unlar tuberosity

flesion

lateral epicondyle->styloid process(radius)

flexion

medial epicondyle->lateral radius

pronation

medial ulna->lateral radius (distal)

pronation

infraspinatous fossa->greater rubercle

rotate laterally

scapula(middle ridge)->greater tubercle

rotate laterally

clavicle,acromion&spine->deltoid tuberosity

abduct