Muscles of the Upper Extremity: Intrinsic Muscles of the Hand Flashcards
Abductor Pollicis Brevis Proximal Attachment
Flexor retinaculum and tubercle of the scaphoid and trapezium
Abductor Pollicis Brevis Distal Attachment
Base of the proximal phalanx of thumb
Abductor Pollicis Brevis Innervation
Median n. [*C8,T1]
Abductor Pollicis Brevis Action
Abducts CMC & MCP joints of the thumb
Assists with:
-Thumb opposition
Flexor Pollicis Brevis Proximal Attachment
Superficial head: Flexor retinaculum and trapezium bone
Deep head: Trapezoid and capitate bones
Flexor Pollicis Brevis Distal Attachment
Base of the proximal phalanx of thumb
Flexor Pollicis Brevis Innervation
Median n. (superficial head) [*C8,T1]
Ulnar n. (deep head) [C8,*T1]
Flexor Pollicis Brevis Action
Flexes CMC & MCP joints of the thumb
Assists with:
-Thumb opposition
Oppenens Pollicis Proximal Attachment
Flexor retinaculum and trapezium bone
Opponens Pollicis Distal Attachment
Entire length of metacarpal I
Opponens Pollicis Innervation
Median n. [*C8,T1]
Opponens Pollicis Action
Opposes CMC joint of the thumb
Adductor Pollicis Proximal Attachment
Oblique head: Capitate bone and bases of metacarpals II & III
Transverse hea: Metacarpal III
Adductor Pollicis Distal Attachment
Base of the proximal phalanx of thumb
Adductor Pollicis Innervation
Ulnar n. [C8,*T1]
Adductor Pollicis Action
Adducts CMC & MCP joints of the thumb
Assists with:
-MCP joint flexion
Abductor Digiti Minimi Proximal Attachment
Pisiform and the tendon of FCI
Abductor Digiti Minimi
Base of the proximal phalanx of the little finger
Abductor Digiti Minimi Innervation
Ulnar n. [C8,*T1]
Abductor Digiti Minimi Action
Abducts MCP joint of the little finger
Flexes MCP joint of the little finger
Assist with:
-Little finger opposition
Flexor Digiti Minimi Proximal Attachment
Hook of the hamate and flexor retinaculum
Flexor Digiti Minimi Distal Attachment
Base of the proximal phalanx of the little finger
Flexor Digiti Minimi Innervation
Ulnar n. [C8,*T1]
Flexor Digiti Minimi Action
Abducts MCP joint of the little finger
Flexes MCP joint of the little finger
Assist with:
-Little finger opposition
Opponens Digiti Minimi Proximal Attachment
Hook of the hamate and flexor retinaculum
Opponens Digiti Minimi Distal Attachment
Entire length of metacarpal V
Opponens Digiti Minimi Innervation
Ulnar n. [C8,*T1]
Opponens Digiti Minimi Action
Opposes CMC joint of the little finger
Lumbricals Proximal Attachment
I and II: FDP tendons of digits II and III
III and IV: FDP tendons of digits III, IV, and V
Lumbricals Distal Attachment
Lateral side of the extensor hood of the respective digit
Lumbricals Innervation
I and II: Median n. [C8,*T1]
III and IV: Ulnar n. [C8,*T1]
Lumbricals Action
Flex MCP joints of digits 2-5
Extend PIP & DIP joints of digits 2-5
Dorsal Interossei Proximal Attachment
First: Adjacent sides of 1st and 2nd metacarpals
Second: Adjacent sides of 2nd & 3rd metacarpals
Third: Adjacent sides of 3rd and 4th metacarpals
Fourth: Adjacent sides of 4th and 5th metacarpals
Dorsal Interossei Distal Attachment
Into the extensor hoods of the proximal phalanges of their respective digits as follows: First: Lateral side of digit II SecondL Lateral side of digit III Third: Medial side of digit III Fourth: Medial side of digit IV
Dorsal Interossei Innervation
Ulnar n. [C8,*T1]
Dorsal Interossei Action
Abduct MCP joints of digits 2-4
Assists with:
-Flexion of MCP joints of digits 2-4
-Extension of PIP & DIP joints of digits 2-4
Palmar Interossei Proximal Attachment
First: Medial side of metacarpal II
Second: Lateral side of metacarpal IV
Third: Lateral side of metacarpal V
Palmar Interossei Distal Attachment
Into the extensor hoods of the proximal phalanges of their respective digits as follows:
First: Medial side of digit II
Second: Lateral side of digit IV
Third: Lateral side of digit V
Palmar Interossei Innervation
Ulnar n. [C8,*T1]
Palmar Interossei Action
Adduct MCP joints of digits 2, 4, & 5
Assists with:
-Flexion of MCP joints of digits 2, 4, & 5
-Extension of PIP & DIP joints of digits 2, 4, & 5
