Hand Muscles (Thenar and Hypothenar) Flashcards
Action of Abductor Digiti Minimi
Abducts 5th digit

Action of Abductor Pollicis Brevis
Abducts thumb and helps oppose it
Action of Adductor Pollicis
Adducts thumb toward middle digit
Action of Flexor Digiti Minimi
Flexes proximal phalanx of 5th digit
Action of Dorsal Interossei 1-4
Abduct digits from axial line and act with lumbricals to flex metacarpophalangeal joints and extend interphalangeal joints
Action of Flexor Pollicis Brevis
Flexes thumb
Action of Lumbricals 1 and 2
Flex digits and metacarpophalangeal joints and extend interphalangeal joints
Action of Lumbricals 3 and 4
Flex digits at metacarpophalangeal joints and extend interphalangeal joints
Action of Opponens Pollicis
Opposition, medial rotations
Action of Opponens Digiti Minimi
Opposition of 5th digit
Action of Palmar Interossei 1-4
Adduct digits toward axial line and assist lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints
Innervation of Abductor Digiti Minimi
Deep branch of ulnar nerve (C8-T1)
Innervation of Abductor Pollicis Brevis
Recurrent branch of median nerve (C8-T1)
Innervation of Adductor Pollicis
Deep branch of ulnar nerve
Innervation of Dorsal Interossei 1-4
Deep branch of ulnar nerve (C8-T1)
Innervation of Flexor Digiti Minimi
Deep branch of the ulnar nerve (C8-T1)
Innervation of Flexor Pollicis Brevis
Recurrent branch of the median nerve (C8-T1)
Innervation of Lumbricals 1 and 2
Median Nerve (C8-T1)
Innervation of Opponens Digiti Minimi
Deep branch of ulnar nerve (C8-T1)
Innervation of Lumbricals 3 and 4
Deep branch of ulnar nerve (C8-T1)
Innervation of Opponens Pollicis
Recurrent branch of the median nerve (C8-T1)
Innervation of Palmar Interossei 1-4
Deep branch of ulnar nerve (C8-T1)
Insertion of Abductor Digiti Minimi
Medial side of base of proximal phalanx of 5th digit
Insertion of Abductor Pollicis Brevis
Lateral side of base proximal phalanx of thumb

Insertion of Adductor Pollicis
Medial side of base of proximal phalanx of thumb

Insertion of Dorsal Interossei 1-4
Extensor expansions and bases of proximal phalanges of digits 2-4

Insertion of Flexor Digiti Minimi
Medial side of base of proximal phalanx of 5th digit

Insertion of Flexor Pollicis Brevis
Lateral side of base proximal phalanx of thumb

Insertion of Opponens Digiti Minimi
Medial border of 5th metacarpal

Insertion of Opponens Pollicis
Lateral side of 1st metacarpal

Insertion of Palmar Interossei 1-4
Extensor expansions of digits and bases of proximal phalanges of digits 2,4, and 5

Insertions of Lumbricals 1 and 2
Lateral side of extensor expansions of digits 1 and 2

Insertions of Lumbricals 3 and 4
Lateral side of extensor expansions of digits 4 and 5

Origin of Abductor Digiti Minimi
Pisiform

Origin of Abductor Pollicis Brevis
Flexor retinaculum and tubercles of scaphoid and trapezium

Origin of Adductor Pollicis
Oblique head: bases of 2nd and 3rd metacarpals, capitate, and adjacent carpals Transverse Head: anterior surface of body of 3rd metacarpal

Origin of Flexor Digiti Minimi
Hook of Hamate, flexor retinaculum

Origin of Flexor Pollicis Brevis
Flexor retinaculum and tubercles of scaphoid and trapezium

Origin of Opponens Digiti Minimi
Hook of hamate, flexor retinaculum

Origin of Dorsal Interossei 1-4
Adjacent sides of two metacarpals

Origin of Opponens Pollicis
Flexor retinaculum and tubercles of scaphoid and trapezium

Origin of Palmar Interossei 1-4
Palmar surfaces of 2nd, 4th, and 5th metacarpals

Origins Lumbricals 3 and 4
Medial three tendons of flexor digitorum profundus

Origins of Lumbricals 1 and 2
Lateral two tendons of flexor digitorum profundus
