Intrinsic Muscles Of The Hand Flashcards
Proximal and distal attachment of opponens pollicis
P: flexor retinaculum and tubercles of scaphoid and trapezium
D: lateral side of 1st metacarpal
Name the thenar muscles
Opponents pollicis, flexor pollicis brevis, abductor pollicis brevis and adductor pollicis
Innervation of opponens pollicis
Median nerve
Actions of opponens pollicis
Oppose the thumb by drawing 1st metacarpal medially to Palm and rotating it medially
O and I of abductor pollicis brevis
O: flexor retinaculum and tubercles of scaphoid and trapezium
I: lateral side of base of proximal phalanx of thumb
Innervation of abductor pollicis brevis
Median nerve
Action if abductor pollicis brevis
Adducts the thumb, helps oppose it
O and I of flexor pollicis brevis
O: flexor retinaculum and tubercles of scaphoid and trapezium
I: lateral side of base of 1st phalanx of the thumb
Innervations for flexor pollicis brevis
Superficial head = median nerve
Deep head = ulnar nerve
Action of flexor pollicis brevis
Flexes thumb
O and I of adductor pollicis
O of Oblique head: bases if 2nd and 3rd metacarpals, capitate and adjacent carpals
O of Transverse head: anterior surface of shaft of 3rd metacarpal
I: medial side of base of proximal phalanx of thumb
Innervation of adductor pollicis
Ulnar nerve
Action of adductor pollicis
Adducts thumb towards border of Palm
List the hypothenar muscles
Abductor Digiti Minimi
Flexor Digiti Minimi brevis
Opponens Digiti
Origin and insertion of abductor Digiti Minimi
O: pisiform
I: medial side if base of proximal phalanx of 5th digit
Nerve for abductor Digiti Minimi
Ulnar nerve
Action of abductor Digiti Minimi
Abducts 5th digit
Assists in flexion of its proximal phalanx
Flexor Digiti Minimi o and I
O: hook of hamate and flexor retinaculum
I: medial border of 5th metacarpal
Nerve for flexor Digiti Minimi
Ulnar nerve
Action of flexor Digiti Minimi
Flexes prox phalanx of 5th digit
Opponens Digiti o and I
O: hook of hamate and flexor retinaculum
I: medial border of 5th metacarpal
Innervation of opponens Digiti
Ulnar nerve
Action of opponens Digiti
Draws 5th metacarpal anterior and rotates it, bringing 5th digit into opposition with thumb
Name short muscles of hand
Lumberjacks and interossei
O and I of 1st and 2nd lumbricals
O: lateral 2 tendons of flexor digitorum Profundus
I: lateral side of extensor expansion and 2nd-5th (radial side)
Innervation of 1st and 2nd lumbricals
Median nerve
Action of lumbricals
Flex the MCP joints; extend interphalangeal joints of 2nd-5th digits
O and I of lumbricals 3-4
O: medial 3 tendons of flexor digitorum Profundus
I: lateral side of extension expansion of 2nd - 5th digits (radial side)
Innervation of 3rd &4rth lumbricals
Ulnar nerve
O and I of dorsal interossei 1-4
O: adjacent sides of 2metacarpals (bi-pennate muscles)
I: bases of proximal phalanges and extensor expansion of 2-4 digits
Innervation of interossei
Ulnar nerve
Action of dorsal interossei 1-4
Abduct 2-4th digits from axial line
Acts with lumbricals in flexing the MCP joints and extending the interphalangeal joints
O and I of palmar interossei 1-3
O: Palmar surfaces of 2, 4& 5th metacarpals (uni pennate )
I: bases of prox phalanges, extensor expansions of 2nd, 4rth and 5th digits
Action of interossei Palmer
Adducts 2,4,5 digits towards axial line, assists lumbricals in flexing metacarpophalangeal joints and extending into phalangeal joints,
