Hand And Wrist

Question 1

How do scaphoid fractures occur?

Answer 1

Fall onto outstretched hand

Hyperextension and impact of scaphoid into rim of radius

Question 2

What are the symptoms of a scaphoid fracture?

Answer 2

Pain in anatomical snuffbox
Exacerbated by moving wrist
Passive range motion reduced

Question 3

Why may a scaphoid fracture have delayed diagnosis?

Answer 3

Not clear initially

Becomes visually when bone reabsorption starts to occur

Question 4

What are common complications of scaphoid fractures?

Answer 4

Avascular necrosis (if fracture at waist of bone due to retrograde blood supply)
Malunion  
Non-union

Question 5

What is a Colles’ fracture?

Answer 5

Extra-articular fracture of distal radial metaphysics with dorsal angulation and impaction

Looks like upturned fork

Question 6

What is the mechanism of Colles’ fractures?

Answer 6

Fall onto outstretched hand with pronated forearm
Wrist is dorsiflexed

Energy transmitted from carpus to distal radius in dorsal direction

Question 7

What are complications of Colles’ fractures?

Answer 7

Malunion (dinner fork deformity)
Median nerve palsy
Secondary OA
Tear in extensor pollcis longus tendon

Question 8

What is a Smith fracture?

Answer 8

Fracture of distal radius with palmar angulation of distal fragment

Question 9

What is the mechanism of a Smith fracture?

Answer 9

Fall onto dorsal of flexed wrist

Direct blow to back of wrist

Question 10

What is a complication of a Smith fracture?

Answer 10

Malunion = garden spade deformity

Question 11

What joints in the hand are normally affected by rheumatoid arthritis?

Answer 11

MCPJ

PIPJ

Question 12

How does RhA present in the hands?

Answer 12

Pain and swelling of effected joint 
Redness 
Stiffness 
Carpal tunnel syndrome (due to swelling)
Flu symptoms 
Rheumatoid nodules on the fingers

Question 13

What is a swan neck deformity?

Answer 13

When the PIPJ joint is hyperextended and DIPJ are flexed

Question 14

Why does swan neck occur?

Answer 14

Tissues in palmar aspect of PIPJ become lax due to adjacent synovitis
Extension> flexion at this joint

At DIPJ elongation or rupture to inversion of extensor digitorum

Question 15

What is Boutonnière deformity?

Answer 15

MCPJ and DIPJ hyperextended

PIPJ flexed

Question 16

Why does Boutonnière deformity occur?

Answer 16

Inflammation of PIPJ lengthening of extensor digitorum at insertion
Lateral bands of extensor digitorum slip down sides of finger so now on palmar surface and instead as acting as extensors, act as flexors

Question 17

What is Psoriatic arthropathy?

Answer 17

Arthritis develops in joints with overlying Psorosis

Affects DIPJs

Question 18

How does Psoratic arthritis present?

Answer 18

Asymmetrically
Fusiform digits
Nail lesions (pitting)

Question 19

Which joint is most commonly affected by OA?

Answer 19

1st CMC

Question 20

How does OA in CMC joint present?

Answer 20

Pain at base of thumb
Stiffness
Swelling
1st metacarpal subluxes in ulnar direction = squaring of hand

Question 21

What causes Heberden’s nodes?

Answer 21

OA

Cystic swelling containing gelatinous hyaluronic acid on dorsal aspect of DIPJ
Once inflammation subsides left with Osteophytes

Reduces manual dexterity

Question 22

What is carpal tunnel syndrome?

Answer 22

Compression of median nerve as travels through carpal tunnel

Question 23

What are risk factors of Carole tunnel syndrome?

Answer 23

Obesity
Pregnancy
Repetitive wrist work
RhA

Question 24

Where is paraesthesia felt in carpal tunnel syndrome?

Answer 24

Distribution of median nerve

Thumb, index, middle and radial half of ring

Question 25

Why is sensation to the palm spared in carpal tunnel syndrome?

Answer 25

The cutaneous branch of the medial nerve is given off before the carpel tunnel

Question 26

Why can long standing carpel tunnel syndrome result in?

Answer 26

Weakness and atrophy of thenar muscles | Still able to flex thumb

Question 27

Where can the ulnar nerve be compressed?

Answer 27

Guyon’s canal

Question 28

Where is paraesthesia felt in ulnar nerve compression in wrist?

Answer 28

Ring and little fingers | Weakening of intrinsic muscles of hand supplied by ulnar nerve

Question 29

What is Dupuyten’s contracture?

Answer 29

Localised thickening and contracture of palmar aponeurosis leading to flexion deformity of fingers

Question 30

How does Dupuytren’s contracture develop?

Answer 30

Thickening in palm Myofibroblasts in nodule contract forming tight bands called cords in palmar fascia Fingers become stuck in flexed position due to close association with aponeurosis

Question 31

What are risk factors for Dupuytren’s contracture?

Answer 31

Type 1 diabetes Smoking Heart disease Trauma to hand and fingers

Question 32

When do injuries to the radial nerve in the radial grove occur?

Answer 32

Mid- shaft humoral fractures

Question 33

In radial groove nerve injuries what will the sensory impairment be?

Answer 33

Posterior cutaneous brach is before the radial groove so unaffected Lower lateral and posterior cutaneous of forearm high in groove so normally fine Paraestesia in superficial brach

Question 34

What muscles are paralysed in radial groove nerve injuries?

Answer 34

Brachioradialis | All extensor muscles of wrist and fingers

Question 35

What muscles are paralysed by a supracaondular fracture that damages the median nerve?

Answer 35

Flexor muscles from medial epicondyle | Pronators and flexors of wrist and hand

Question 36

How will the arm appear in a supracondular fracture that damage the median nerve?

Answer 36

Supurnated Weak flexion of wrist (adduction due to pull of flexor carpi ulnaris) Flexion of thumb weak

Question 37

What is the hand of Benediction?

Answer 37

When a patient attempts to are a fist with a high median nerve injury Only able to flex medial 2 digits

Question 38

What causes low level median nerve injuries?

Answer 38

Penetrating wrist injury | Compression of carple tunnel

Question 39

What is the presentation of a low medial nerve injury?

Answer 39

``` Muscles paralysed= LOAF Lubricals to index and middle finger Opppones pollicis Abductor polllicis brevis Flexor pollicis brevis ``` Ape hand deformity

Question 40

What is ape hand deformity?

Answer 40

Results from lower median nerve injury Thenor eminence is flattered Thumb adducted and laterally rotated

Question 41

What functions will be lost in wrist level ulnar nerve injury?

Answer 41

``` Muscles of hypothenor eminence Adductor pollcis Deep head of flexor pollicis brevis Interossi Lumbricals the ring and little finger Palmaris brevis Palmar branches if medial 1 an a half digits ```

Question 42

What is claw hand and why does it occur?

Answer 42

Little and ring finger hyperextended at MCPJ and flexed at both IPJ at rest This is as lumbricals supplying these are paralysed (these flex at MCPJ and extend at IPJ)

Question 43

What causes the ulnar never to be damaged in injuries at the elbow?

Answer 43

Medial epicondyle fractures | Compression of cubital tunnel

Question 44

What muscles are affected in a high ulnar nerve injury?

Answer 44

Same as in a low injury Paralysis of flexor carpi ulnaris Ulnar half of flexor digitorum profundus Loss of sensation in palmar and dorsal cutaneous branches

Question 45

How does an ulnar claw appear with a high level ulnar nerve lesion?

Answer 45

Less pronounced than with lower injury As no flexion at DIPJ of medial fingers as flexor digitorum profundus paralysed Only hyperextension at MCPJs