Hand and wrist anatomy

Question 1

extensor carpi radialis brevis

Answer 1

Origin: Lateral epicondyle of humerus.
Insertion: Base of 3rd metacarpal (dorsal surface).
Action: extends and radially deviates hand
Innervation: radial nerve

Question 2

Flexor carpi radialis

Answer 2

Origin: medial epicondyle of humerus
Insertion 2nd and 3rd metacarpals
innervation: median nerve
action: flexion and radial deviation of the radiocarpal joint

Question 3

flexor carpi ulnaris

Answer 3

origin: medial epicondyle of the humerus and superior posterior border of the ulnar
insertion: pisiform, hamate, and base of 5th MC
innervation: ulnar nerve
action: F and ulnar deviation of radiocarpal joint

Question 4

flexor digitorum superficialis

Answer 4

origin: Medial epicondyle of humerus, coronoid process of
ulna, and a ridge along lateral margin of anterior surface of radius
insertion: Middle phalanges of each finger
innervation: Median nerve (C7,8 T1)
action: F the PIP joint

Question 5

flexor digitorum profundus

Answer 5

origin: Anterior medial surface of body of ulna
insertion: bases of distal phalanx
innervation: median and ulnar
action: flexes the DIP joints

Question 6

extensor carpi radialis longus

Answer 6

origin: Lateral supracondylar ridge of humerus
insertion: 2nd metacarpal
innervation: radial nerve
action: extends and radially deviates the radiocarpal joint

Question 7

extensor carpi ulnaris

Answer 7

origin: Lateral epicondyle of humerus and posterior border of ulna
insertion: 5th MC
innervation: radial nerve
action: extension and ulnar deviation of the radiocarpal joint

Question 8

extensor digitorum

Answer 8

origin: lateral epicondyle of humerus
insertion: distal and middle phalanges of each giner
innervation: radial nerve
action: extends the digits

Question 9

extensor indicis

Answer 9

origin: posterior surface of the ulna
insertion: tendon of extensor digitorum of index finger
innervation: radial nerve
action: extends index finger

Question 10

extensor digiti minimi

Answer 10

origin: lateral epicondyle of humerus
insertion: tendon of extensor digitorum on 5th phalanx
innervation: radial nerve
action: extends the little finger

Question 11

extensor pollicis longus

Answer 11

Origin Posterior surface of middle third of ulna and interosseus membrane
Insertion Posterior aspect of base of distal phalanx of thumb
innervation: radial nerve
action: extends DIP of thumb joint

Question 12

extensor pollicis brevis

Answer 12

origin: posterior surface of middle of radius
insertion: 1st metacarpal
innervation: radial nerve
action: extends 1st CMC joint

Question 13

supinator

Answer 13

Lateral epicondyle of humerus, supinator crest of ulna, radial collateral ligament, annular ligament
Insertion Lateral proximal radial shaft
innervation: radial nerve
action: supination of radioulnar joint

Question 14

biceps brachii

Answer 14

origin: Long head - supraglenoid tubercle; Short head - coracoid process of scapula
insertion: Radial tuberosity and bicipital aponeurosis
innervation: musculocutaneous nerve
action: supination and flexion of the elbow joint

Question 15

brachioradialis

Answer 15

origin: Medial and lateral borders of distal end of humerus
insertion: Superior to styloid process of radius
innervation: Radial Nerve (C5,6)
action: elbow flexion in neutral pronation/ supination

Question 16

pronator teres

Answer 16

origin: Medial epicondyle of humerus and coronoid process of ulna
insertion: Midlateral surface of radius
innervation: median nerve
joint: superior and inferior radioulnar joint

Question 17

pronator quadratus

Answer 17

origin: Distal portion of shaft of ulna
insertion: Distal portion of shaft of radius
innervation: median nerve
action: pronation of radioulnar joint

Question 18

what muscles make up the hypothenar eminence

Answer 18

• abductor digiti minimi
• flexor digiti minimi brevis
• palmaris brevis
• opponens digiti minimi

Question 19

what muscles make the thenar eminence

Answer 19

abductor pollicis
flexor pollicis brevis
opponens pollicis brevis

Question 20

Describe the contents and borders of the anatomic snuffbox

Answer 20

contents: radial artery and scaphoid
border ulnarly: EPL
Radial border: EPB and APL

Question 21

what movement happens at the PIP

Answer 21

hinge joint allowing 110 deg arc of motion though articular asymmetry allows for 9 deg of supination with full flexion