Brachial plexus

Question 1

Draw brachial plexus

Answer 1

Question 2

After their formation, roots of brachial plexus pass between

Answer 2

anterior and middle scalene muscles to enter posterior triangle of neck

Question 3

What is superior trunk

Answer 3

C5 and C6 roots

Question 4

What is middle trunk

Answer 4

C7 root continuation direct

Question 5

What is inferior trunk

Answer 5

combination of C8 and T1 root

Question 6

Axillary and radial nerves are terminal branches of posterior cord and supply

Answer 6

extensor compartments within upper limb

Question 7

Ulnar, medina and musculocutanous nerve are formed from anterior divisions via medial and lateral cords and supply the

Answer 7

flexor compartments

Question 8

Long thoracic nerve spinal root values

Answer 8

C5-C7

Question 9

Medial pectoral nerve spinal root value and lateral

Answer 9

C8-T1

C5-C7

Question 10

What is M shape

Answer 10

musculocutaneous, median and ulnar nerves

Superficial to axially artery

Question 11

Mechanism of upper brachia plexus injury

Answer 11

excessive increase in angle between neck and shoulder e.g. fall or when a baby is born if shoulder dystocia
C5 and C6

Question 12

What is waiter’s tip

Answer 12

Limb hangs by the side in internal rotation with an adducted arm and extended elbow

Injury to upper roots of brachial plexus- Erb’s palsy

Question 13

Mechanism of injury to lower brachial plexus

Answer 13

forced hyperextension or hyperabduction
e.g. grab onto tree branch or baby’s arm delivered first
Klumpke’s palsy
C8 and T1

Question 14

What is claw hand

Answer 14

hyperextension of all metacarpophalangeal joints (not just ring and little finger seen in ulnar nerve injury)
Flexion of interphalangeal joints and abduction of the thumb and wasting of interossei

Question 15

Which nerve passes anterior to the lateral epicondyle of the humerus

Answer 15

Median

Question 16

Which nerve innervates pectoralis minor

Answer 16

Medial pectoral nerve

Question 17

Which nerve provides the sensory innervation to the radial side of the forearm

Answer 17

Musculocutaneous nerve

Question 18

Which nerve passes posteriorly to medial epicondyle of humerus

Answer 18

Ulnar

Question 19

Which nerve is responsible for wrist flexion

Answer 19

Median nerve- innervates anterior forearm

Question 20

Which nerve provides the motor innervation to the posterior arm

Answer 20

Radial nerve

Question 21

Which nerve provides sensory innervation to the regimental badge

Answer 21

Axillary

Question 22

Which nerve innervates teres minor

Answer 22

Axillary nerve

Question 23

Which nerve passes down lateral side of upper arm between bicep brachii and brachialis muscles

Answer 23

Musculocutaneous nerve

Question 24

Which nerve enters the hand via Guyon’s canal

Answer 24

Ulnar nerve

Question 25

Which muscle without innervation is responsible for the pathology of winged scapula

Answer 25

Serratus anterior muscle

Question 26

What does the Latissmus dorsi do

Answer 26

Extend, adduct and medially rotate the humerus at the shoulder

Question 27

Point of origin for the Supraspinatus muscle

Answer 27

Supraspinous fossa

Question 28

What is innervated by the lateral pectoral nerve

Answer 28

Pec major

Question 29

What does trapezius muscle do

Answer 29

Abduct the shoulder

Question 30

Attachments of the trapezius muscle

Answer 30

Skull, T2 spinous process and clavicle

Question 31

Extrinsic shoulder muscles

Answer 31

Trapezius, rhomboid major, latissimus dorsi

Question 32

Which muscle is mainly responsible for shoulder abduction from 0-15 degrees

Answer 32

Supraspinatous

Question 33

Muscles of rotator cuff

Answer 33

Supraspinatous, infraspinatous, teres minor and subscapularis SITS

Question 34

Which nerve innervates deltoid muscle

Answer 34

Axillary nerve

Question 35

Which muscle may undergo atrophy in long standing axillary nerve palsy

Answer 35

Deltoid

Question 36

Which vessel accompanies the axillary nerve as it passes through the quadrangular space

Answer 36

Posterior circumflex humoral artery and vein

Question 37

Which structure forms the inferior border of the quadrangular space

Answer 37

Teres major

Question 38

A patient with stab wound to axilla- which branch of musculocutaneous nerve affected

Answer 38

Lateral cutaneous nerve or forearm - innervates skin of anterolateral aspect of forearm muscle

Question 39

Which muscle is least likely to undergo atrophy in chronic carpal tunnel syndrome

Answer 39

Flexor pollicis longus (located on anterior forearm, receives innervation before the median nerve passes through the carpel tunnel)

Question 40

Pronator quadratus is innervated by

Answer 40

Anterior interosseous branch of median nerve

Question 41

Deformity when median nerve is damaged at elbow

Answer 41

hand of benediction d

Question 42

Which injury is most likely to result in wrist drop

Answer 42

Humoral shaft fracture - radial nerve tightly bound in spiral groove of humerus

Question 43

How many sensory branches does the radial nerve give rise to

Answer 43

4

Question 44

Damage with superficial branch of radial nerve

Answer 44

Purely sensory

Question 45

What is flexor digitorum profundus medial half innervated by

Answer 45

Ulnar nerve

Question 46

Which area does the ulnar nerve provide cutaneous innervation to

Answer 46

Medial one and a half fingers