Intrinsic Muscles of the Hand

Question 1

Opponens Pollicis

Answer 1

THENAR MUSCLES
Attachments:

Superior/Proximal: Flexor Retinaculum & Scaphoid & Trapezium
Inferior/Distal: Lateral 1st Metacarpal

Action:

To Oppose Thumb, It draws 1st Metacarpal Medially and then Rotates it

Question 2

Abductor Pollicis

Answer 2

THENAR MUSCLES
Attachments:

Superior/Proximal: Flexor Retinaculum & Scaphoid & Trapezium
Inferior/Distal: Lateral Base Proximal Phalanx of Thumb

Action:

Abducts Thumb & Helps Rotate It

Question 3

Flexor Pollicis Brevis

Answer 3

THENAR MUSCLES
Attachments:

Superior/Proximal: Flexor Retinaculum & Scaphoid & Trapezium
Inferior/Distal: Lateral Base Proximal Phalanx of Thumb

Action:

Flexes Thumb

Question 4

Adductor Pollicis

Answer 4

THENAR MUSCLES
Attachments:

Superior/Proximal: Oblique Head to Base 2nd and 3rd Metacarpal and Capitate and Adjacent Metacarpals & Transverse Head to Anterior Shaft 3rd Metacarpal
Inferior/Distal: Medial Base Proximal Phalanx of Thumb

Action:

Adducts Thumb toward Lateral Border of Palm

Question 5

Abductor Digiti Minimi

Answer 5

HYPOTHENAR MUSCLES
Attachments:

Superior/Proximal: Pisiform
Inferior/Distal: Medial Base Proximal Phalanx 5th Digit

Action:

Abducts 5th digit & Assists Flexion

Question 6

Flexor Digit Minimi Brevis

Answer 6

HYPOTHENAR MUSCLES
Attachments:

Superior/Proximal: Hook of Hamate & Flexor Retinaculum
Inferior/Distal: Medial Base Proximal Phalanx 5th Digit

Action:

Flexes Proximal Phalanx 5th Digit

Question 7

Opponens Digiti

Answer 7

HYPOTHENAR MUSCLES
Attachments:

Superior/Proximal: Hook of Hamate & Flexor Retinaculum
Inferior/Distal: Medial 5th Metacarpal

Action:

Draws 5th Metacarpal Anterior and Rotates it

Question 8

Lumbricals

Answer 8

SHORT MUSCLES
Attachments:

Superior/Proximal: 1st and 2nd to Lateral 2 Tendons of FDP & 3rd and 4th to Medial 3 Tendons of FDP
Inferior/Distal: Lateral Extensor Expansions of 2nd-5th Digits

Action:

Flex MCP Joints & Extend IP Joints 2nd-5th Digits

Question 9

Dorsal Interossei 1st-4th

Answer 9

SHORT MUSCLES
Attachments:

Superior/Proximal:Adjacent Sides of 2 Metacarpals
Inferior/Distal: Bases Proximal Extensor Expansions 2nd-4th Digits

Action:

Abduct 2nd-4th Digits from Axial Line & Act with Lumbricals

Question 10

Palmar Interossei 1st-3rd

Answer 10

SHORT MUSCLES
Attachments:

Superior/Proximal: Palmar Surfaces of 2nd, 4th and 5th Metacarpals
Inferior/Distal: Bases Proximal Extensor Expansions 2nd, 4th and 5th Digits

Action:

Adduct 2nd, 4th, and 5th Digits toward Axial Line & Assist Lumbricals