Flexor
pollicis
longusAnterior surface of radius and
interosseous membranePalmar base of
distal phalanx of
thumbAnterior
interosseous
branch of median
nerve (C7-8)Anterior interosseous
arteryFlexes phalanges of
thumbPronator
quadratusDistal fourth of anterior ulna Distal fourth of
anterior radiusAnterior
interosseous
branch of median
nerve (C7-8)Anterior interosseous
arteryPronates forearmMuscle Origin Insertion Innervation Blood supply Action
BrachioradialisProximal two thirds of lateral
supracondylar ridge of humerusLateral side of distal
end of radiusRadial nerve
(C5-C6)Radial
recurrent
arteryFlexes forearmExtensor carpi
radialis longusDistal one-third of lateral
supracondylar ridge of humerusDorsal base of
second metacarpalRadial nerve
(C6-C7)Radial artery
and radial
recurrent
arteryExtends and abducts
hand at wristExtensor carpi
radialis brevisLateral epicondyle of humerus
(common extensor tendon)Dorsal base of third
metacarpalDeep branch
of radial nerve
(C7-C8)Radial artery
and radial
recurrent
arteryExtends and abducts
hand at wristExtensor
digitorumLateral epicondyle of humerus
(common extensor tendon)Extensor expansions
of medial four digitsPosterior
interosseous
nerve (C7-C8)Posterior
interosseous
arteryExtends medial four
digits; assists in wrist
extension
Extensor digiti
minimiLateral epicondyle of humerus
(common extensor tendon)Extensor expansion
of fifth digitPosterior
interosseous
nerve (C7-C8)Posterior
interosseous
arteryExtends fifth digitExtensor carpi
ulnarisLateral epicondyle of humerus
and posterior border of ulna
(common extensor tendon)Dorsal base of fifth
metacarpalPosterior
interosseous
nerve (C7-C8)Posterior
interosseous
arteryExtends and abducts
hand at wristAnconeus Posterior surface of lateral
epicondyle of humerusLateral surface of
olecranon and
posterior proximal
ulnaRadial nerve
(C5-7)Deep brachial
arteryAssists triceps in
extending elbow; abducts
ulna during pronationMuscle Origin Insertion Innervation Blood supply Action
SupinatorLateral epicondyle of humerus,
supinator crestLateral, posterior and
anterior surfaces of proximal
third of radiusDeep branch of
radial nerve (C6-
C7)Radial recurrent and
posterior interosseous
arteriesSupinates
forearmAbductor
pollicis
longusPosterior surface of ulna,
radius, and interosseous
membraneBase of first metacarpal Posterior
interosseous
nerve (C7-C8)Posterior interosseous
arteryAbducts and
extends thumbExtensor
pollicis
brevisPosterior surface of radius and
interosseous membraneBase of proximal phalanx of
thumbPosterior
interosseous
nerve (C7-C8)Posterior interosseous
arteryExtends
proximal
phalanx of
thumb
Extensor
pollicis
longusPosterior surface of middle
third of ulna and interosseous
membraneBase of distal phalanx of
thumbPosterior
interosseous
nerve (C7-C8)Posterior interosseous
arteryExtends distal
phalanx of
thumb
Extensor
indicisPosterior surface of ulna and
interosseous membraneExtensor expansion of
second digitPosterior
interosseous
nerve (C7-C8)Posterior interosseous
arteryExtends
second digitAnterior (flexor) compartment
Superficial group (origin at medial epicondyle)
Pronator teres (pronates forearm)
Flexor carpi radialis (flexes and abducts wrist)
Palmaris longus (absent in some individuals; tenses palmar aponeurosis)
Flexor carpi ulnaris (flexes and adducts wrist)
Flexor digitorum superficialis (flexes PIP joints via four tendons)
Deep group
Flexor digitorum profundus (flexes at DIP joint)
Flexor pollicis longus (flexes thumb)
Pronator quadratus (pronates forearm)
Posterior (extensor) compartment
Superficial group (origin at lateral epicondyle)
Brachioradialis (flexes elbow)
Extensor carpi radialis longus and brevis (extend and abduct wrist)
Extensor digitorum (extends fingers)
Extensor digiti minimi (extends fifth digit)
Extensor carpi ulnaris (extends and adducts wrist)
Anconeus (extends elbow)
Deep group (originate from shaft of radius, ulna, and interosseous membrane)
Supinator (supinates forearm)
Abductor pollicis longus (abduct thumb)