Upper Limb

Question 1

What the carpal tunnel syndrome does not affect palm sensation?

Answer 1

• superficial palmar cutaneous branch of medial nerve passes superficial to the carpal tunnel

Question 2

What can cause the Erb-Duchenne palsy?

Answer 2

• damage of C5-C6 spinal nerves roots (upper trunk)

- head and shoulder forcibly separated (accident, birth injury, herniation of disk)

Question 3

Why Erb-Duchenne palsy leads in waiter’s tip sign?

Answer 3

• can’t rotate and abduct the arm at the shoulder
• can’t supinate and flex the forearm
• internally rotate and adduct the arm at shoulder and pronation with extension of forearm

Question 4

What can cause klumpke’s paralysis?

Answer 4

• lesion at C8-T1 spinal nerve roots (inferior trunk)

- upper limb forcefully abducted above the head (grabbing object when falling, thoracic outlet syndrome, birth injury)

Question 5

Why in klumpke’s paralysis do you see “claw and ape hands”?

Answer 5

• can’t flex the metacarpophalangeal
• can’t extend interphalangeal joints of digits 2-5
• can’t apposite the thumb
• extension of MP, flexion of IP, and adducted thumb

Question 6

What muscles does not innervate the median nerve in anterior compartment?, who innervate them?

Answer 6

• ulnar half of flexor digitorum profundus and flexor carpi ulnaris
• ulnar nerve innervates them

Question 7

What movement or function is spared on radial nerve lesions distal to the axilla?

Answer 7

Elbow extension

Question 8

Why do you see the sign “hand of benediction” in a supracondylar fracture of humerus? Wha other sign can we see?

Answer 8

• median nerve lesion
• can’t flex 3 digits - no complete a fist
• preserve the flexion of last 2 fingers innervate by ulnar
• ape hand

Question 9

What level of median nerve lesion doesn’t present benediction hand?, what other functions are spared?

Answer 9

• wrist: carpal tunnel or laceration
• flexion of wrist and digits, pronation
• present ape hand

Question 10

Which nerve lesion leads in winged scapula?

Answer 10

Long thoracic nerve

Question 11

What roots innervate sensation of the medial arm and forearm?

Answer 11

• C8: medial forearm to fingers

- T1: medial arm to elbow

Question 12

Which roots or nerves innervate sensation of lateral arm and forearm?

Answer 12

• musculocutaneous - lateral forearm

- axillary - lateral arm

Question 13

Content of the carpal tunnel

Answer 13

4 tendons of flexor digitorium superficialis, 4 tendons flexor digitorium profundus, tendon of flexor pollicis longus, median nerve.

Question 14

Most common tendon affected of the rotator cuff

Answer 14

Tendon of supraspinatus

Question 15

What structures may result affected by humeral surgical neck fracture?

Answer 15

Laceration of axillary nerve and posterior humeral circumflex artery

Question 16

What structures can be damage if mid-shaft (radial groove) humeral fracture occur?

Answer 16

Radial nerve and profunda brachii artery

Question 17

What structures can result damaged in a humeral head dislocation?

Answer 17

Radial or axillary nerves

Question 18

What structure result damaged in the fracture of the hook of the hamate?

Answer 18

Ulnar nerve as it passes into the hand

Question 19

Most common bone fracture of the carpal bones, what can result since that

Answer 19

Scaphoid (separate distal and proximal head)

- avascular necrosis of its proximal head (blood supply enter by its distal head)

Question 20

Most commonly dislocated bone of carpal ones, and what can result since that?

Answer 20

Lunate

- if occurs anteriorly into carpal tunnel ▶️ compress median nerve, carpal tunnel syndrome