Wrist/hand fracture (distal radius, scaphoid, metacarpal / phalangeal)

Question 1

What is the mechanism of injury in scaphoid fractures?

Answer 1

FOOSH causes axial compression of the scaphoid with the wrist hyperextended and radially deviated

Question 2

What are common causes of scaphoid fractures?

Answer 2

RTA - holding steering wheel

Football

Question 3

What is the major blood supply to the scaphoid?

Answer 3

Around 80% of the blood supply is derived from the dorsal carpal branch (branch of the radial artery), in a retrograde manner.

Question 4

What is a common complication of scaphoid fractures?

Answer 4

Avascular necrosis of the scaphoid

Non-union –> pain and early OA

Question 5

What are the presenting features of scaphoid fracture?

Answer 5

Pain along the radial aspect of the wrist, at the base of the thumb

Loss of grip / pinch strength

Question 6

What are the signs of scaphoid fracture?

Answer 6

1. Point of maximal tenderness over the anatomical snuffbox = This is a highly sensitive (around 90-95%), but poorly specific test (<40%) in isolation
2. Wrist joint effusion = Hyperacute injuries (<4hrs old), and delayed presentations (>4days old) may not present with joint effusions.
3. Pain elicited by telescoping of the thumb (pain on longitudinal compression)
4. Tenderness of the scaphoid tubercle (on the volar aspect of the wrist)
5. Pain on ulnar deviation of the wrist

Clinical examination has a high diagnostic probability (sensitivity 100%; specificity 74%) when [1], [3], and [4] are positive on examination.

Question 7

How sensitive is clinical examination at picking up scaphoid fractures?

Answer 7

100%

Question 8

What investigations should be done for scaphoid fracture?

Answer 8

Scaphoid views XR - PA, lateral and oblique (wrist pronated 45 degrees) AND Siter view (PA with wrist in ulnar deviation and beam at 20 degrees)

CT is better than XR - usually done if no signs but suspicion

MRI - definitive. NICE suggests to consider this first line.

Question 9

List the three places for scaphoid fractures.

Answer 9

Waist (60%)

Distal tubercle (20%)

Proximal pole (20%)

Question 10

What is the initial management of scaphoid fractures?

Answer 10

immobilisation with a Futuro splint or standard below-elbow backslab

referral to orthopaedics

• clinical review with further imaging should be arranged for7-10 days later when initial radiographs are inconclusive

Question 11

What is the ortho management of scaphoid fractures?

Answer 11

Dependent on the patient and type of fracture:

undisplaced fractures of the scaphoid waist

• cast for 6-8 weeks
• union is achieved in > 95%
• certain groups e.g. professional sports people may benefit from early surgical intervention

displaced scaphoid waist fractures - requires surgical fixation

proximal scaphoid pole fractures - require surgical fixation

Question 12

What is a Bennett’s fracture? What is the mechanism of injury?

Answer 12

• Intra-articular fracture at the base of the thumb metacarpal
• Impact on flexed metacarpal, caused by fist fights. Abductor pollicis longus attaches here.

Question 13

What is seen on XR in Bennett’s fracture?

Answer 13

X-ray: triangular fragment at the base of metacarpal

Question 14

What is a Smith’s fracture? What is the mechanism of injury?

Answer 14

= reverse Colles’ fracture

• Volar angulation of distal radius fragment (Garden spade deformity)
• Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed

Question 15

What is a Colles’ fracture? What is the mechanism of injury?

Answer 15

• MOI: fall onto extended outstretched hands
• Described as a dinner fork type deformity

Question 16

What are the 3 features of classical Colles’ fractures?

Answer 16

Classical Colles’ fractures have the following 3 features:

1. Transverse fracture of the radius
2. 1 inch proximal to the radio-carpal joint
3. Dorsal displacement and angulation

Question 17

What are the 5 Ds of Colles’ fracture?

Answer 17

Colles’ - Dorsally Displaced Distal radius → Dinner fork Deformity

Question 18

What is a Monteggia’s fracture? What is the mechanism of injury?

Answer 18

Dislocation of the proximal radioulnar joint in association with an ulna fracture

MOI: Fall on outstretched hand with forced pronation

Needs prompt diagnosis to avoid disability

Question 19

What is a Barton’s fracture? What is the mechanism of injury?

Answer 19

Distal radius fracture (Colles’/Smith’s) with associated radiocarpal dislocation

MOI: Fall onto extended and pronated wrist

Question 20

What is a Galeazzi fracture? What is the mechanism of injury?

Answer 20

Radial shaft fracture with associated dislocation of the distal radioulnar joint

MOI: Occur after a fall on the hand with a rotational force superimposed on it.

Question 21

What is found on XR and examination in Galeazzi fractures?

Answer 21

On examination, there is bruising, swelling and tenderness over the lower end of the forearm.

X Rays reveal the displaced fracture of the radius and a prominent ulnar head due to dislocation of the inferior radio-ulnar joint.

Question 22

What type of fracture does this sign indicate?

Answer 22

Triquetrum - fall onto wrist in dorsiflexion and ulnar deviation

Question 23

What type of fracture is shown?

Answer 23

Boxer fracture

• MOI: direct blow with clenched fist against a solid surface –> transverse fracture of the 5^th metacarpal
• Clinical presentation: 95% in young men
• Management: can be treated conservatively but it is quite unstable so K-wire fixation is required for better cosmesis.

Question 24

What is the main complication after healing of metacarpal fractures and how is this picked up on examination?

Answer 24

Residual rotational deformity as this may make closure of the hand into a fist impossible without the affected finger overlapping one of it’s neighbours. Subsequent osteotomy may then be required.

Although usually minor and not impairing function.

Question 25

What are some types of phalanx fractures?

Answer 25

Proximal, middle or distal phalanges may be affected. Proximal/middle phalanges usually transverse fractures which may be forward angulated, rotated, or fractured into the joint. Distal phalanx injuries are usually crush injuries e.g. caught in door or struck by hammer. Usually comminuted with a lot of soft tissue injury.

Question 26

What is the management of phalanx fractures?

Answer 26

Undisplaced → neighbour strapping for 2-3 weeks i.e. damaged finger is strapped to its neighbour and movement encouraged Displaced → reduction including any rotational deformity (i.e. when making a fist fingers will cross over each other). Splint in flexion for 3 weeks then to neighbour for 3 weeks. Unstable → internal fixation with screws or crossed Kirschner wiring Distal phalanx crush injury → plastic mallet finger splint, reposition nail bed with sutures, paraffin if nail bed fully avulsed. NB: Proximal and middle usually from direct trauma but distal usually from crush injuries.

Question 27

What is the management of a Colles' fracture?

Answer 27

* Reduction under anaesthesia e.g. Bier's block, axillary block or general anaesthesia * Manipulate into position of palmar flexion, ulnar deviation and pronation * Plaster from elbow to MCP joints in loke with proximal palm crease (not at base of fingers) * Patient advice to move fingers, elbow and shoulder * Fracture should have united by 6 weeks NB: if undisplaced or minimally displaced then Colles' backslab. colles