O & I: Intrinsic Hand Muscles Flashcards
What are the 4 Thenar Muscles?
1) Opponens Pollicis
2) Abductor Pollicis Brevis
3) Flexor Pollicis Brevis
4) Adductor Pollicis
What are the 3 Hypothenar muscles?
1) Abductor digiti minimi
2) Flexor Digiti minimi brevis
3) Opponens digiti
What are the 3 short muscles?
1) Lumbricals
2) Dorsal interossei
3) Palmar interossei
Origin: Opponens Pollicis
Flexor retinaculum and tubercles of scaphoid and trapezium
Insertion: Opponens Pollicis
Lateral side of 1st metacarpal
Innervation: Opponens Pollicis
recurrent branch of median nerve (C8, T1)
Action: Opponens Pollicis
to oppose thumb, it draws 1st metacarpal medially to center of palm and rotates it medially
Origin: Abductor Pollicis Brevis
Flexor retinaculum and tubercles of scaphoid and trapezium
Insertion: Abductor Pollicis Brevis
Lateral side of base of proximal phalanx of thumb
Innervation: Abductor Pollicis Brevis
recurrent branch of median nerve (C8, T1)
Action: Abductor Pollicis Brevis
abducts thumb; helps oppose it
Origin: Flexor Pollicis Brevis
Flexor retinaculum and tubercles of scaphoid and trapezium
Insertion: Flexor Pollicis Brevis
Lateral side of base of proximal phalanx of thumb
Innervation: Flexor Pollicis Brevis
Superficial head: recurrent branch of median n. (C8-T1)
Deep head: deep branch of ulnar nerve (C8, T1)
Action: Flexor Pollicis Brevis
Flexes Thumb
Origin: Adductor Pollicis
Oblique Head: Bases of 2nd and 3rd metacarpals, capitate, and adjacent carpals
Transverse Head: anterior surface of shaft of 3rd metacarpal
Insertion: Adductor Pollicis
medial side of base of proximal phalanx of thumb