Intrinsic Hand Muscles

Opponens pollicis

▪O: Trapezium and flexor retinaculum

▪I: First metacarpal

▪A: Opposes the thumb

▪N: Median nerve

Flexor pollicis brevis

▪O: Trapezium and flexor retinaculum

▪I: Proximal phalanx of thumb

▪A: Flexes MCP, CMC of thumb

▪N: Median nerve

Abductor pollicis brevis

▪O: Scaphoid, trapezium, and flexor retinaculum

▪I: Proximal phalanx of thumb

▪A: Abducts the thumb

▪N: Median nerve

Adductor pollicis

Deep palm

▪O: Capitate, base of metacarpals II-III, and distal 2/3 of palmar surface of metacarpal III

▪I: Base of proximal phalanx of thumb

▪A: Adducts thumb

▪N: Ulnar nerve

Lumbricals

Deep palm

▪O: Tendon of FDP

▪I: Tendon of ED

▪A: Flex MCP while extending PIP/DIP

▪N: I-II: median

III-IV: ulnar

Dorsal and palmar interossei

Deep palm

▪O: Metacarpals

▪I: Base of proximal phalanx

▪A: DAB/PAD

▪N: Ulnar nerve

Abductor digiti minimi

▪O: Pisiform and tendon of FCU

▪I: Proximal phalanx digit V (PINKY finger)

▪A: Abducts digit V

▪N: Ulnar nerve

Flexor digiti minimi

▪O: Hamate and flexor retinaculum

▪I: Base of proximal phalanx digit V

▪A: Flexes MCP of digit V (PINKY finger)

▪N: Ulnar nerve

Opponens digiti minimi

▪O: Hamate and flexor retinaculum

▪I: Fifth metacarpal

▪A: Digit V opposition

▪N: Ulnar nerve