Brachial Plexus

Question 1

Flexion

Answer 1

Smaller angle
More acute
Anterior → anterior surface

Question 2

Extension

Answer 2

Larger angle

Question 3

Abduction

Answer 3

Away

Thumb moves away from fingers

Question 4

Adduction

Answer 4

Come together

Thumb moves toward fingers

Question 5

Ventral Ramus

Answer 5

Posterior extensors (elevators)
Anterior flexors (depressors)

Question 6

Shoulder Muscles

Answer 6

Move the arm
Elevators - deltoid group (axillary nerve)
Depressors - pectoral

Question 7

Arm Muscles

Answer 7

More the forearm
Triceps (radial nerve)
Brachial group (musculocutaneous nerve)

Question 8

Forearm Muscles

Answer 8

Move the wrist & fingers
Extensors (radial nerve)
Flexors (median & ulnar nerve)

Question 9

Roots

Answer 9

5 roots
Ventral rami
C5 → T1

Question 10

Trunks

Answer 10

3 trunks
Superior
Middle
Inferior

Question 11

Divisions

Answer 11

6 divisions
Anterior (3)
Posterior (3)

Question 12

Cords

Answer 12

3 cords
Lateral
Posterior
Medial
Labelled in relation to axillary artery

Question 13

Branches

Answer 13

5 branches
Musculocutaneous
Axillary
Median (M)
Radial
Ulnar

Question 14

Musculocutaneous Nerve

Answer 14

Anterior flexor

Arm - coracobrachialis, brachialis, & biceps brachii

Question 15

Median Nerve

Answer 15

Anterior flexor
Forearm & thumb
Under transverse carpal ligament
Provides motor innervation to forearm flexars, thenar muscles, & 1st/2nd lumbricals plus sensory innervation to rays I, II, III, and lateral 1/2 digit IV

Question 16

Radial Nerve

Answer 16

EXTENSOR
Dorsal elevators
Provides motor innervation to all muscles in arm & forearm extensor compartments plus sensory innervation to part arm, forearm, & hand dorsum

Question 17

Ulnar Nerve

Answer 17

Anterior flexor
Ulnar side
Forearm & hand
Lateral to transverse carpal ligament
Provides motor innervation to forearm flexors, hypothenar muscles, adductor pollicis, 3rd/4th lumbricals, & all interossei plus sensory innervation to medial 1/2 ray II & V

Question 18

Subclavian Artery →

Answer 18

Axillary → brachial → radial & ulnar

Question 19

ANTERIOR to the Anterior Scalene

Answer 19

1. Phrenic nerve
2. Subclavian vein
3. Transverse cervical artery
4. Suprascapular artery

Question 20

POSTERIOR to the Anterior Scalene

Answer 20

1. Brachial plexus (roots)

2. Subclavian artery

Question 21

3 Muscles Attach to Coracoid Process

Answer 21

1. Coracobrachialis
2. Pectoralis minor
3. Brachialis

Question 22

Damage to _____ causes arm extension & pronation

Answer 22

Erb’s palsy
Brachial plexus upper roots
Upper roots serve as flexors in the shoulder & arm

Question 23

Erb’s Palsy

Answer 23

Loss musculocutaneous innervation

Question 24

Klumpke’s Palsy

Answer 24

Damage to brachial plexus lower roots
Muscles that move the hand & wrist
Limitations on elbow extension & wrist flexion

Question 25

Scapular Winging

Answer 25

Results from damage to the long thoracic nerve C5-C7 & weakness in serratus anterior

Question 26

Flexors attach to _____

Answer 26

Medial epicondyle (humerus)

Question 27

Extensors attach to _____

Answer 27

Lateral epicondyle (humerus)

Question 28

Brachioradialis*

Answer 28

Exception to the rule
Radial nerve innervation
Extensor → flexor

Question 29

Lumbricals

Answer 29

Complex 2 joint muscles that produces flexion at the metacarpophalangeal joint & extension at the interphalangeal joint