Brachial plexus

Question 0

Dorsal scapular nerve distribution

Answer 0

Innervates rhomboids

Occasionally supplies levator scap

Question 1

Dorsal scapular origin

Answer 1

Posterior aspect of anterior ramus of C5 with frequent contibution of C4

Question 2

Long thoracic nerve origin

Answer 2

Posterior aspect of anterior rami of C5, C6, C7

Question 3

Long thoracic nerve distribution

Answer 3

Serratus anterior

Question 4

Suprascapular nerve origin

Answer 4

Superior trunk, receiving fibers from C5, C6 and often C4

Question 5

Suprascapular nerve distribution

Answer 5

Supraspinatus and infraspinatus muscles

Glenohumeral joint

Question 6

Subclavian nerve origin

Answer 6

Superior trunk, receiving fibers from C5, C6 and often C4

Question 7

Subclavian nerve distribution

Answer 7

Subclavius and sternoclavicular joint (accessory phrenic root innervates diaphragm)

Question 8

Lateral pectoral origin

Answer 8

Side branch of lateral cord, receiving fibers from C5, C6, C7

Question 8

Lateral pectoral distribution

Answer 8

Primarily pectoralis major, but some lateral pectoral nerve fibers pass to pectoralis minor via branch to medial pectoral nerve

Question 8

Musculocutaneous nerve origin

Answer 8

Terminal branch of lateral cord, receiving fibers from C5-C7

Question 8

Musculocutaneous nerve distribution

Answer 8

Muscles of anterior compartment of arm (coracobrachialis, biceps brachii, and brachialis)
Skin of lateral aspect of forearm

Question 9

Median nerve origin

Answer 9

Lateral root of median nerve is a terminal branch of lateral cord (C6, C7)
Medial root of median nerve is a terminal branch of medial cord (C8, T1)

Question 10

Median nerve distribution

Answer 10

Muscles of anterior forearm compartment (except flexor carpi ulnaris and ulnar half of flexor digitorum profundus)
Five intrinsic muscles in thenar half of palm and palmar skin

Question 11

Medial pectoral nerve origin

Answer 11

Side branches of medial cord, receiving fibers from C8, T1

Question 12

Medial pectoral nerve distribution

Answer 12

Pectoralis minor and sternocostal part of pec major

Question 13

Medial cutaneous nerve of arm origin

Answer 13

Side branches of medial cord, receiving fibers from C8 & T1

Question 14

Medial cutaneous nerve of arm distribution

Answer 14

Skin of medial side of arm, as far distal as medial epicondyle of humerus and olecranon of ulna

Question 15

Median cutaneous nerve of forearm origin

Answer 15

Side branches of medial cord, receiving fibers from C8, T1

Question 16

Median cutaneous nerve of forearm distribution

Answer 16

Skin of medial side of forearm, as far distal as wrist

Question 17

Ulnar nerve origin

Answer 17

Larger terminal branch of medial cord, receiving fibers from C8, T1 and sometimes C7

Question 18

Ulnar nerve distribution

Answer 18

Flexor carpi ulnaris and ulnar half of flexor digitorum profundus (forearm)
Most intrinsic muscles of hand
Skin of hand medial to axial line of digit 4

Question 19

Upper subscapular nerve origin

Answer 19

Side branch of posterior cord, receiving fibers from C5

Question 20

Upper subscapular nerve distribution

Answer 20

Superior portion of subscapularis

Question 21

Lower subscapular nerve origin

Answer 21

Side branch of posterior cord, receiving fibers from C6

Question 22

Lower subscapular nerve distribution

Answer 22

Inferior portion of subscapularis and teres major

Question 23

Thoracodorsal nerve origin

Answer 23

Side branch of posterior cord, receiving fibers from C6, C7, C8

Question 24

Thoracodorsal nerve distribution

Answer 24

Latissimus dorsi

Question 25

Axillary nerve origin

Answer 25

Terminal branch of posterior cord, receiving fibers from C5, C6

Question 26

Axillary nerve distribution

Answer 26

Glenohumeral joint, teres minor and deltoid muscles, skin of superolateral arm (over inferior part of deltoid)

Question 27

Radial nerve origin

Answer 27

Larger terminal branch of posterior cord ( largest branch of plexus)
Receiving fibers from C5-T1

Question 28

Radial nerve distribution

Answer 28

All muscles of posterior compartments of arm and forearm
Skin of posterior and inferolateral arm
Posterior forearm
Dorsum of hand lateral to axial line of digit 4