Lower arm muscles

Question 1

Anterior compartment, flexors superficial group and nerves:

Answer 1

• Pronator teres (median)
• Flexor carpi radialis (median)
• Palmaris longus (median)
• Flexor carpi ulnaris (ulnar nerve)

Question 2

Anterior compartment, flexors intermediate group and nerves:

Answer 2

Flexor digitorum superficialis (median nerve)

Question 3

Anterior compartment, flexors deep group and nerves:

Answer 3

• Flexor digitorum profundus (median and ulnar)
• Flexor pollicis longus (median nerve)
• Pronator quadratus (median nerve)

Question 4

Pronator teres action? Nerve?

Answer 4

• pronation
• weak elbow flexion
• median nerve

Question 5

Flexor carpi radialis (carpal tunnel) action? Nerve?

Answer 5

• wrist flexion
• radial deviation
• elbow flexion
• median nerve

Question 6

Palmaris longus action? Nerve?

Answer 6

• wrist flexion
• radial deviation
• elbow flexion
• median nerve

Question 7

Flexor carpi ulnaris action? Nerve?

Answer 7

• wrist flex
• ulnar deviation
• elbow flexion
• ulnar nerve

Question 8

Flexor digitorum superficialis action? Nerve?

Answer 8

• flexion of middle and proximal phalanges
• wrist and elbow flex
• median nerve

Question 9

Flexor digitorum profundus action? Nerve?

Answer 9

• finger flexion
• wrist flexion
• median and ulnar nerves

Question 10

Flexor pollicis longus action? Nerve?

Answer 10

• thumb flexion
• wrist flexion
• median nerve

Question 11

Pronator quadratus action? Nerve?

Answer 11

• pronation
• median nerve

Question 12

Lateral “mobile wad” (radialis group)

Answer 12

• Brachioradialis
• ECRL
• ECRB

Question 13

Dorsal (posterior compartment) forearm (superficial and deep) and nerves:

Answer 13

• Superficial
  
  • Extensor dititorum (radial nerve)
  • extensor digiti minimi (radial nerve)
  • Extensor carpi ulnaris (radial nerve)
• Deep
  
  • Supinator (radial nerve)
  • abductor pollicis longus (radial nerve)
  • extensor pollicis brevis and longus (radial nerve)
  • extensor indicis (radial nerve)

Question 14

Extensor digitorum action? Nerve?

Answer 14

• extension of MCP joints
• wrist extension
• weak elbow extension
• radial nerve

Question 15

Extensor digiti minimi action? Nerve?

Answer 15

• extension and abduction of 5th finger
• wrist extension
• weak elbow extension
• radial nerve

Question 16

Extensor carpi ulnaris action? Nerve?

Answer 16

• extension of wrist
• ulnar deviation
• weak elbow extension
• radial nerve

Question 17

Supinator action? Nerve?

Answer 17

• supination
• elbow extension
• radial nerve

Question 18

Abductor pollicis longus action? Nerve?

Answer 18

• extends 1st metacarpal
• wrist radial deviation
• radial nerve

Question 19

Extensor pollicis brevis action? Nerve?

Answer 19

• extension of proximal phalanx of thumb
• radial deviation
• radial nerve

Question 20

Extensor pollicis longus action? Nerve?

Answer 20

• extends distal phalanx of thumb
• extends first metacarpal
• wrist extension
• radial deviation
• radial nerve

Question 21

Extensor indicis action? Nerve?

Answer 21

• extends index finger and wrist
• radial nerve

Question 22

Extensor carpi radialis longus action?

Extensor carpi radialis brevis action?

Answer 22

• wrist extension and radial deviation
• elbow flexion

Question 23

Brachioradialis action?

Answer 23

• elbow flexion
• half pronation from supination and vice versa

Question 24

Tendons in the anatomical snuffbox:

Answer 24

• abductor policis longus
• extensor policis brevis
• extensor pollicis longus

Question 25

Lumbricals action?

Answer 25

flex digits at MCP and extend at IP

Question 26

Palmar interossei action? Nerve?

Dorsal interossei action? Nerve?

Answer 26

• Palmar interossei:
  
  • Adduct fingers (toward) middle finger at MCP joints (PAD)
  • assist lumbricals deep
  • ulnar nerve
• Dorsal interossei:
  
  • Abduct fingers (away) from middle finger at MCP joints (DAB)
  • assist lumbricals deep
  • ulnar nerve

Question 27

• Nerve?
  
  • Abductor digiti minimi
  • Flexor digiti minimi brevis
  • Opponens ditigi minimi

Answer 27

ulnar nerve