Upper Extremity Nerves

Question 1

What nerves make up the ROOTS of the Brachial Plexus and at what levels?

Answer 1

• Dorsal scapular (C4) C5

* Long thoracic C5, 6, 7

Question 2

What nerves make up the UPPER TRUNK of the Brachial Plexus and at what levels?

Answer 2

• Subclavius C5, 6

* Suprascapular (C4) C5, 6

Question 3

What nerves make up the LATERAL CORD of the Brachial Plexus and at what levels?

Answer 3

• Lateral pectoral C5, 6, 7
• Musculocutaneous C5, 6, 7
• Median (C5), C6, 7

Question 4

What nerves make up the POSTERIOR CORD of the Brachial Plexus and at what levels?

Answer 4

• Upper subscapular C5, 6, (7)
• Thoracodorsal C6, 7, 8
• Lower subscapular C5, 6, (7)
• Axillary C5, 6
• Radial C5, 6, 7, 8 (T1)

Question 5

What nerves make up the MEDIAL CORD of the Brachial Plexus and at what levels?

Answer 5

• Medial pectoral C7, 8, T1
• Median C8, T1
• Ulnar C8, T1

Question 6

What muscle does the Long thoracic n innervate and at what levels?

Answer 6

*Serratus anterior (C5, 6, 7)

Question 7

What muscle does the Subclavian n innervate and at what levels?

Answer 7

*Subclavius (C5, 6)

Question 8

What muscle does the lateral pectoral n innervate and at what levels?

Answer 8

*pectoralis major: clavicular head (C5, 6)

Question 9

What muscles does the Musculocutaneous n innervate and at what levels?

Answer 9

• Coracobrachialis (C5, 6, 7)
• Biceps Brachii (C5, 6)
• Brachialis (C5, 6)

Question 10

What muscles does the Accessory n (Cranial Nerve XI) innervate?

Answer 10

• Sternocleidomastoid

* Trapezius

Question 11

What muscles does Dorsal scapular n innervate and at what levels?

Answer 11

• Levator scapula (C5)

* Rhomboids (C4, 5)

Question 12

What muscles does Suprascapular n innervate and at what levels?

Answer 12

• Supraspinatus (C4, 5, 6)

* Infraspinatus (C5, 6)

Question 13

What muscle does Upper subscapular n innervate and at what levels?

Answer 13

*subscapularis (C5, 6, 7)

Question 14

What muscles does Lower subscapular n innervate and at what levels?

Answer 14

• Subscapularis (C5, 6, 7)

* Teres major (C5, 6)

Question 15

What muscle does Thoracodorsal n innervate and at what levels?

Answer 15

*Latissimus dorsi (C6, 7, 8)

Question 16

What muscles does Axillary n innervate and at what levels?

Answer 16

• Deltoid (C5, 6)

* Teres minor (C5, 6)

Question 17

What muscles does Radial n innervate and at what levels?

Answer 17

• Triceps brachii (C6, 7, 8)
• Brachioradialis (C5, 6, 7)
• Anconeus (C7, 8, T1)
• Extensor carpi radialis longus (C6, 7)
• Extensor carpi radialis brevis (C6, 7)
• Supinator (C7, 8)
• Extensor digitorum (C6, 7, 8)
• Extensor digiti minimi (C7, 8)
• Extensor carpi ulnaris (C7, 8)
• Abductor pollicis longs (C7, 8)
• Extensor pollicis brevis (C7, 8)
• Extensor pollicis longus (C7, 8)
• Extensor indicis (C7, 8)

Question 18

What muscles does Medial pectoral n innervate and at what levels?

Answer 18

• Pectoralis major: sternocostal head (C7, 8, T1)

* Pectoralis minor (C8, T1)

Question 19

What muscles does Median n (forearm) innervate and at what levels?

Answer 19

• Pronator teres (C6, 7)
• Flexor carpi radialis (C6, 7)
• Palmaris longs (C7, 8)
• Flexor digitorum superficialis (C7, 8, T1)
• Flexor digitorum profundus (radial 2 fingers) (C8, T1)
• Flexor pollicis longus (C8, T1)
• Pronator quadratus (C8, T1)

Question 20

What muscles does Ulnar n (forearm) innervate and at what levels?

Answer 20

• Flexor carpi ulnaris (C7, 8)

* Flexor digitorum profundus (ulnar 2 fingers) (C8, T1)

Question 21

What muscles does Median n (hand) innervate and at what levels?

Answer 21

• Abductor pollicis brevis (C8, T1)
• Opponens pollicis (C8, T1)
• Flexor pollicis brevis (superficial head) (C8, T1)
• 1st and 2nd lumbricals (C8, T1)

Question 22

What muscles does Ulnar n (hand) innervate and at what levels?

Answer 22

• Adductor pollicis (C8, T1)
• Flexor pollicis brevis (deep head) (C8, T1)
• Abductor digiti minimi (C8, T1)
• Opponens digiti minimi (C8, T1)
• Flexor digiti minimi brevis (C8, T1)
• 3rd and 4th lumbricals (C8, T1)
• Dorsal interossei (all 4) (C8, T1)
• Palmar interossei (all 3) (C8, T1)