Upper Arm Muscles Flashcards
triceps brachii long head
origin: inferior margin of glenoid cavity
insertion: olecranon of ulna
action: forearm extensor, antagonist of forearm flexors
triceps brachii lateral head
origin: posterior humerus
insertion: olecranon of ulna
action: forearm extensor, antagonist of forearm flexors
triceps brachii medial head
origin: inferior margin of glenoid cavity
insertion: olecranon of ulna
action: forearm extensor, antagonist of forearm flexors
anconeus
origin: lateral epicondyle of humerus
insertion: lateral aspect of olecranon of ulna
action: abducts ulna during forearm pronation, synergist of triceps brachii in forearm extension
biceps brachii short head
origin: coracoid process
insertion: radial tuberosity
action: flexion and supination of forearm
biceps brachii long head
origin: supraglenoid tubercle and lip of glenoid cavity
insertion: radial tuberosity
action: flexion and supination of forearm
brachioradialis
origin: lateral ridge at distal end of humerus
insertion: base of radial styloid process
action: flexion and supination of forearm
brachialis
origin: distal portion of anterior humerus
insertion: coronoid process of ulna
action: flexor of forearm
pronator teres
origin: medial epicondyle of humerus and coronoid process of ulna
insertion: midshaft of radius
action: synergist with pronator quadratus to pronate forearm
flexor carpi radialis
origin: medial epidcondyle of humerus
insertion: base of metacarpal II and II
action: flexor and abductor of the hand
palmaris longus
origin: medial epidcondyle of humerus
insertion: palmar aponeurosis
action: flexor and abductor of the hand
flexor carpi ulnaris
origin: medial epidcondyle of humerus and olecranon and posterior surface of ulna
insertion: base of metacarpal V, pisiform and hamate bones
action: flexes and abducts of the hand
flexor digitorum superficialis
origin: medial epidcondyle of humerus, coronoid process of ulna, shaft of radius
insertion: middle phalanges of fingers II-V
action: flexes hand and middle phanages of fingers II-V
flexor pollicis longus
origin: anterior surface of radius and interosseous
insertion: distal phalanx of thumb
action: flexes thumb
flexor digitorum profundus
origin: anteromedial surface of ulna. interosseous membrance and coronoid process
insertion: distal phalanges of fingers II-V
action: flexes distal phalanges
pronator quadratus
origin: distal portion of anterior ulnar surface
insertion: anterior surface of radius, distal end
action: pronates forearm
extensor carpi radialis longus
origin: lateral supercondylar ridge of humerus
insertion: base of metacarpal II
action: extends and abducts hand
extensor carpi radialis brevis
origin: lateral epicondyle of humerus
insertion: base of metacarpal III
action: extends and abducts hand
extensor digitorum
origin: lateral epicondyle of humerus
insertion: by 4 tendons into distal phalanges of fingers II-V
action: prime mover of finger extension
extensor carpi ulnaris
origin: lateral epicondyle of humerus, posterior border of ulna
insertion: base of metacarpal V
action: extends and abducts hand
extensor pollicis longus and brevis
origin: dorsal shaft of ulna and radius, interosseous membrane
insertion: base of distal phalanx of thumb and proximal phalanx of thumb
action: extend thumb
abductor pollicis longus
origin: posterior surface of radius and ulna, interosseous membrane
insertion: metacarpal I and trapezium
action: abducts extend thumb
supinator
origin: lateral epicondyle of humerus, proximal ulna
insertion: proximal end of radius
action: synergist of biceps brachii to supinate forearm, antagonist of pronator muscles
infraspinatus
origin: infraspinous fossa of scapula
insertion: greater tubercle of humerus
action: lateral rotation of arm
