Peripheral Nerve Lesions: Upper Limb

Question 1

What is the nerve supply to the upper limb?

Answer 1

the brachial plexus

Question 2

What are the spinal nerve roots of the brachial plexus?

Answer 2

C5
C6
C7
C8
T1

Question 3

What are the 5 main terminal nerves of the brachial plexus?

Answer 3

• Musculotaneous
• Axillary
• Radial
• Median
• Ulnar

Question 4

What is the nerve root of musculotaneous nerve?

Answer 4

C5
C6
C7

Question 5

What does the musculotaneous nerve supply?

Answer 5

Sensory: skin of lateral forearm

Motor: BBC (anterior compartment of arm)
Biceps
Brachialis
Coracobrachialis

Question 6

What is the nerve root of the axillary nerve?

Answer 6

C5, C6

Question 7

What does the axillary nerve suppy?

Answer 7

Sensory: “sergeant’s patch” skin over lower part of deltoid

Motor:
Deltoid (abducts, flexes, extend shoulder)
Teres minor (externally rotate shoulder)

Question 8

What is the nerve root of radial nerve?

Answer 8

C5, C6, C7, C8, T1

Question 9

What does the radial nerve supply?

Answer 9

Sensory:
>posterior arm and foreram >lateral 2/3 dorsum of hand
>proximal dorsal aspect of lateral 31/2 fingers

Motor:
>Triceps
>Posterior compartment muscles of forearm

Question 10

What is the nerve route of median nerve?

Answer 10

C5, C6, C7, C8, T1

Question 11

What does the median nerve supply?

Answer 11

Sensory:
>skin over thenam eminence
>lateral 2/3 palm of hand
>palmar aspect of lateral 3 and 1/2 fingers
>dorsal fingertips of lateral 3 and 1/2 fingers (thumb, index, middle finger, 1/2 of ring finger)

Motor:
>Anterior compartment of forearm
>Intrinsic muscles of hand

Question 12

What is the nerve route origin of ulnar nerve?

Answer 12

C8, T1

Question 13

What does the ulnar nerve supple?

Answer 13

Sensory:
>Skin of hypothenar eminence
>medial 1/3 palm of hand
>palmar aspect of medial 1 and 1/2 fingers
>medial 1/3 dorsum of hand
>dorsal aspect of medial 1 and 1/2 fingers

Motor:
>2 muscles of anterior compartment
>most of intrinsic muscles of hand

Question 14

What common injuries can damage the axillary nerve?

Answer 14

• Fracture of surgical neck of humerus
• Stab wounds to posterior shoulder
• Anterior should dislocation
• Pressure of crutches on armpits

Question 15

What are the clinical features of axillary nerve palsy?

Answer 15

• Numb sergeants patch
• Paralysis of deltoid = weak should abduction, extension and flexion
• Paralysis of teres minor =weak shoulder external rotation
• Wasting of deltoid muscle

Question 16

What are the common injuries of the radial nerve?

Answer 16

• fracture of proximal humerus, shaft of humerus or radius
• stab wounds
• pressure of crutches on armpit

Question 17

What are the clinical features of a radial nerve palsy?

Answer 17

• Numb skin over posterior arm, posterior forearm, radial distribution of dorsum of hand
• Paralysis of posterior compartment =weak elbow extension
• Paralysis of posterior compartment of forearm =weak wrist extension, thumb extension
• absent tricep and supinator reflex

*“wrist drop” defomity!

Question 18

What are the common injurys of the median nerve?

Answer 18

• Supracondylar fracture of humerus
• Stab wounds
• Deep wrist laceration
• Compression by carpal tunnel syndrome

Question 19

What are the clinical features of median nerve palsy?

Answer 19

• Sensory loss over thenar eminence and median distribution of hand
• Weak forearm pronation, wrist flexion and abduction, weak finger flexion
• “Hand of benediction” cannot make a fist with all fingers as cannot flex index of middle finger

Question 20

What are the common injuries of ulnar nerve?

Answer 20

• Supracondylar fracture of humerus
• Fractures or soft tissue injuries to medial epicondyle of humerus
• stab wound
• Compression either at cubital tunnel in elbow or in wrist

Question 21

What are the features of an ulnar nerve palsy?

Answer 21

• Sensory loss of hypothenar eminence
• Weak wrist flexion and adduction,
• weak extension of ring and little fingers
• Claw hand deformity at rest