Upper Limb

Question 1

Name the terminal branches of brachial plexus

Answer 1

Anterior division:

• lateral: musculocutaneous nerve
• medial: ulnar nerve
• lateral + medial: median nerve

Posterior division:

• radial nerve
• axillary nerve

Question 2

What is proximal-distal gradient:

Answer 2

The more proximal muscles are innervated by the higher

segments (C5 and C6) and the more distal muscles are innervated by the lower segments (C8 and T1)

Question 3

What is Erb-Duchenne Palsy?

Answer 3

Lesion of C5,6 roots (usually by separation of head and shoulder). Affects axillary, suprascapular, musculocutaneous nerves. Arm is medially rotated and adducted, forearm is extended and pronated. “Waiter’s tip”

Question 4

What is Klumpke’s Palsy?

Answer 4

Lesion of C8, T1 roots (usually when upper limb is abducted above the head). Affects ulnar and median nerves. “Claw hand”. +- Horner syndrome

Question 5

What is the function of musculocutaneous nerve?

Answer 5

• flex elbow

- supination

Question 6

What is the function of Median nerve?

Answer 6

• wrist flexion (+ulnar)
• flexion of 1,2,3 digits
• thumb opposition
• sensory innervation of 1, 2, 3 1/2 digits on palm side

Question 7

What is the function of Ulnar nerve?

Answer 7

• wrist flexion (weak, +median)
• flexion of 3, 4 digits
• adduction and abduction digits 2-5
• adduct the thumb
• sensor innervation of 1/2 4, 5 digits on both sides

Question 8

What is the function of Axillary nerve?

Answer 8

• abduct shoulder 15° - 110° (deltoid muscle)

- lateral rotation of shoulder (teres minor m.)

Question 9

What is the function of Radial nerve?

Answer 9

• extension of elbow, wrist, MP joints

- supination (supinator m.)

Question 10

What is the function of Long thoracic nerve?

Answer 10

Innervation of m. serratus anterior (protracts and rotates scapula) => Lesion results in “winged scapula”

Question 11

What is the function of suprascapular nerve?

Answer 11

Innervation of supraspinatus m. (abducts shoulder 0° - 15°) and infraspinatus m. (laterally rotates shoulder)

Question 12

How does sensory innervation of the hand occur?

Answer 12

Palmar: 
- medial - ulnar nerve
- lateral - median nerve
Dorsal:
- medial - radial nerve
- lateral - ulnar nerve

Question 13

Does carpal tunnel syndrome affect sensory innervation of the hand? Why?

Answer 13

No, because cutaneous branch of median nerve passes superficial to the carpal tunnel. Associated with edema during pregnancy

Question 14

Name the possible causes and consequences of Radial nerve injury

Answer 14

1) Injury in axilla (Saturday night palsy, crutches, shoulder dislocation):
- loss of extension in elbow, wrist and MP joints
- sensory loss in posterior arm, forearm and dorsal of thumb
- “wrist drop”

2) Injury in arm (midshaft humerus fraction, lateral epicondyle, radial head dislocation):
- loss of extension in wrist and MP joints
- sensory loss in posterior forearm and dorsal of thumb
- “wrist drop”

3) Injury in wrist (laceration):
- sensory loss
- no motor loss

Question 15

Name the possible causes and consequences of Median nerve injury

Answer 15

1) Injury in elbow (humerus fraction):
- loss of 1, 2, 3 digital flexion => hand of benediction
- loss of thumb opposition
- thenar atrophy
- loss of sensation (by median nerve)

2) Injury in wrist (carpal tunnel, laceration):
- thenar atrophy
- loss of sensation (if laceration)
- normal wrist and digital flexion

Question 16

Name the possible causes and consequences of Ulnar nerve injury

Answer 16

Medial epicondyle, laceration, fracture of hook of hamate:

• loss of hypothenar muscles, 3,4 lumbricals muscles, all interossei and adductor policies muscle
• loss of abduction and adduction of digits 2-5
• “claw hand”
• sensory loss (by ulnar nerve)

Question 17

Name the possible causes and consequences of Axillary nerve injury

Answer 17

Fracture of the surgical neck of the humerus, inferior dislocation of shoulder:

• loss of abduction of the arm to the horizon
• sensory lost over the deltoid muscle

Question 18

Name the possible causes and consequences of Long thoracic nerve injury

Answer 18

Radical mastectomy, stab wound to the lateral chest: “winged scapula”

Question 19

Name the possible causes and consequences of Suprascapular nerve injury

Answer 19

• loss of shoulder abduction between 0 and 15 degrees (supraspinatus
  muscle)
• weakness of lateral rotation of shoulder (infraspinatus muscle)

Question 20

Name the possible causes and consequences of Musculocutaneous nerve injury

Answer 20

• loss of elbow flexion and weakness in supination

- loss of sensation on lateral aspect of the forearm

Question 21

What’s the difference between Claw hand, hand of Benediction and Ape hand?

Answer 21

Claw hand:

• lesion of ulnar nerve => loss of 3,4 lumbricans m. => opposite muscles work => claw hand
• passive sign!

Hand of Benediction:

• lesion of median nerve ABOVE THE WRIST => loss of flexion of 1, 2, 3 digits while trying to make a fist
• active sign!

Ape (обезьяна) hand:
- carpal tunnel syndrom (lesion of median nerve) => thenar atrophy and loss of thumb abduction

Question 22

How does arterial supply to the upper limb occur?

Answer 22

1) subclavian a.
2) axillary a.
- lateral thoracic a. (to mammary gland with long thoracic n. )
- subscapular a.
- posterior humeral circumflex a. (at surgical neck with axillary nerve)
3) brachial a.
- radial a. (deep palmar arch)
- ulnar a. (superficial palmar arch)

Question 23

Which muscles form Rotator Cuff? Which of them is the most frequently damaged?

Answer 23

• supraspinal m.
• infraspinal m.
• teres minor m.
• subscapularis
  (SIRS)

Supraspinal m. is the most frequently damaged

Question 24

How does humerus dislocation occur?

Answer 24

inferior -> anterior -> superior

Question 25

Which structures may dislocation of humerus damage?

Answer 25

Axillary and radial nerves

Question 26

Which structures may fracture of surgical nerve damage?

Answer 26

Axillary nerve and humeral circumflex a.

Question 27

Which structures may mid-shaft fracture of humerus damage?

Answer 27

Radial nerve and a. profunda brachii (in radial groove)

Question 28

What may scaphoid fracture lead to?

Answer 28

Avascular necrosis of proximal part of scaphoid bone

Question 29

What may lunate dislocation lead to?

Answer 29

Carpal tunnel syndrome (always dislocates anteriorly)

Question 30

What may fracture of the hook of hamate lead to?

Answer 30

Ulnar nerve lesion

Question 31

What is De Quervain tenosynovitis?

Answer 31

Noninflammatory thickening of abductor pollicis longus and extensor pollicis brevis tendons characterized by pain or tenderness at radial styloid. ⊕ Finkelstein test (pain at radial styloid with active or passive stretch of thumb tendons).

Question 32

What is Ganglion cyst?

Answer 32

Fluid-filled swelling overlying joint or tendon sheath, most commonly at dorsal side of wrist. Arises from herniation of dense connective tissue.

Question 33

What is Radial head subluxation (nursemaid’s elbow)?

Answer 33

Common elbow injury in children < 5 years. Caused by a sudden pull on the arm Ž immature annular ligament slips over head of radius. Injured arm held in flexed and pronated position.

Question 34

What is Greenstick fracture?

Answer 34

Incomplete fracture extending partway through
width of bone following bending stress;
bone fails on tension side;
compression side intact (compare to torus fracture). Bone is bent like a green twig.

Question 35

What is Torus (buckle) fracture?

Answer 35

Axial force applied to immature bone Ž cortex
buckles on compression side and fractures.
Tension side (other side of cortex) remains intact.