Muscles of the Wrist and Hand

Question 1

O:, Medial epicondyle of the humerus via the common flexor tendon
I: Bases of metacarpals Il and III

Answer 1

FLEXOR CARPI RADIALIS (FIG. 21.54
A: Flexes the wrist, Abducts the wrist, Flexes the elbow
N: Median nerve

Question 2

O: Medial epicondyle of the humerus via the common flexor tendon, Medial olecranon, Posterior proximal two thirds of the ulna
I: Base of metacarpal V, Pisiform, Hook of hamate

Answer 2

FLEXOR CARPI ULNARIS (SEE FIG. 21.54)
A: Flexes the wrist, Adducts the wrist
N: Ulnar nerve

Question 3

O:, Medial epicondyle of the humerus via the common flexor tendon,
I: Palmar aponeurosis

Answer 3

PALMARIS LONGUS (SEE FIG. 21.54)
A: Flexes the wrist, Cups (tenses) the palm
N: Median nerve

Question 4

O: Medial epicondyle of the humerus via the common flexor tendon, Anterior proximal radial shaft, Coronoid process of the ulna
I: Middle phalanges of digits Il through V

Answer 4

FLEXOR DIGITORUM SUPERFICIALIS (SEE FIG. 21.54)
A: Flexes the wrist, Flexes the fingers at the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) j
N: Median nerve

Question 5

O: Proximal three-fourths of the anterior ulnar shaft, Interosseous membrane
I: Distal phalanges of digits ll through V

Answer 5

FLEXOR DIGITORUM PROFUNDUS (FIG. 21.55)
A: Flexes the wrist, Flexes the fingers at the distal interphalangeal (DIP), PIP, and MCP joints
N: Ulnar nerve, Median nerve

Question 6

O:, Lateral supracondylar ridge of the humerus,
I: Posterior base of metacarpal lI

Answer 6

EXTENSOR CARPI RADIALIS LONGUS (FIG. 21.56
A: Extends the wrist, Abducts the wrist
N: Radial nerve

Question 7

O:, Lateral epicondyle of the humerus via the common extensor tendon,
I: Posterior base of metacarpal Ill

Answer 7

EXTENSOR CARPI RADIALIS BREVIS (SEE FIG. 21.56)
A: Extends the wrist, Abducts the wrist
N: Radial nerve

Question 8

O:, Lateral epicondyle of the humerus via the common extensor tendon,
I: Metacarpal V

Answer 8

EXTENSOR CARPI ULNARIS (SEE FIG. 21.56)
A: Extends the wrist, Adducts the wrist
N: Radial nerve

Question 9

O:, Lateral epicondyle of the humerus via the common extensor tendon
I: Middle and distal phalanges of digits Il through V

Answer 9

EXTENSOR DIGITORUM (SEE FIG. 21.56)
A: Extends the wrist, Extends the fingers at the DIP, PIP, and MCP joints
N: Radial nerve

Question 10

O:, Lateral epicondyle of the humerus via the common extensor tendon
I: Posterior middle and distal phalanges of digit V via the tendon of the extensor digitorum

Answer 10

EXTENSOR DIGITI MINIMI (SEE FIG. 21.56)
A: Extends the little finger (digit V)
N: Radial nerve

Question 11

O: Posterior distal ulnar shaft, Interosseous membrane
I: Middle and distal phalanges of the index finger (digit Il)

Answer 11

EXTENSOR INDICIS (FIG. 21.57)
A: Extends the index finger (digit Il)
N: Radial nerve

Question 12

O: Posterior ulnar shaft—middle region (longus), Posterior radial shaft-distal region (brevis), Interosseous membrane (brevis and longus)
I: Posterior distal phalanx of the thumb (longus), Posterolateral proximal phalanx of the thumb (brevis)

Answer 12

EXTENSOR POLLICIS LONGUS AND BREVIS
A: Extends the thumb (digit l)
N: Radial nerve

Question 13

O: Anterior radial shaft—middle region (longus), Interosseous membrane (longus), Trapezium (brevis), Transverse carpal ligament (brevis)
I: Anterior distal phalanx of the thumb (longus), Proximal phalanx of the thumb (brevis)

Answer 13

FLEXOR POLLICIS LONGUS (SEE FIG. 21.57) AND BREVIS
A: Flexes the thumb
N: Median nerve (longus), Median and ulnar nerves (brevis)

Question 14

O: Trapezium, Transverse carpal ligament,
I: Anterior metacarpal l

Answer 14

OPPONENS POLLICIS (FIG. 21.59
A: Opposes the thumb (adduction), Flexes the thumb
N: Median nerve

Question 15

O: Posterior ulnar and radial shaft-middle region (longus), Interosseous membrane (longus), Trapezium (brevis), Scaphoid (brevis), Transverse carpal ligament (brevis)
I: Lateral metacarpal I (longus), Lateral proximal phalanx of the thumb (brevis)

Answer 15

ABDUCTOR POLLICIS LONGUS (SEE FIG. 21.57) AND BREVIS (FIG. 21.60)
A: Abducts the thumb (longus and brevis)
N: Radial nerve (longus), Median nerve (brevis)

Question 16

O: Hook of hamate, Transverse carpal ligament,
I: Proximal phalanx of digit V

Answer 16

FLEXOR DIGITI MINIMI (FIG. 21.61)
A: Flexes digit V (little finger)
N: Ulnar nerve

Question 17

O: Pisiform, Tendon of flexor carpi ulnaris,
I: Proximal phalanx of digit V (little finger)

Answer 17

ABDUCTOR DIGITI MINIMI (SEE FIG. 21.57)
A: Abducts digit V (little finger)
N: Ulnar nerve

Question 18

O: Hamate, Transverse carpal ligament,
I: Metacarpal V

Answer 18

OPPONENS DIGITI MINIMI (FIG. 21.62)
A: Adducts digit V (moves little finger into opposition)
N: Ulnar nerve

Question 19

Flexion of the wrist.

Answer 19

Flexor carpi radialis, Flexor carpi ulnaris, Palmaris longus, Flexor digitorum superficialis, Flexor digitorum profundus

Question 20

Extension of the wrist.

Answer 20

Extensor carpi radialis longus, Extensor carpi radialis brevis, Extensor carpi ulnaris, Extensor digitorum

Question 21

Abduction of the wrist.

Answer 21

Flexor carpi radialis, Extensor carpi radialis longus, Extensor carpi radialis brevis

Question 22

Adduction of the wrist.

Answer 22

Flexor carpi ulnaris, Extensor carpi ulnaris