General Trauma - Fractures

Question 1

what is a fracture?

Answer 1

medical term for a break in the bone

- can be complete or incomplete

Question 2

what is primary bone healing?

Answer 2

method of bone healing when fracture gap is small (<1mm), hairline fractures and fractures which are compressed with plates and screws
bone simply bridges the gap with new bone formed by osteoblasts

Question 3

what is secondary bone healing?

Answer 3

inflammatory response temporarily fills a larger gap with pluropotential stem cells at the fracture site to act as a scaffold for new bone to be laid down

Question 4

what is the process of secondary bone healing?

Answer 4

• fracture occurs
• haematoma occurs with inflammation from damaged tissues
• macrophages and osteoclasts remove debris and resorb the bone ends
• granulation tissue forms from fibroblasts and new blood vessels
• chondroblasts form cartilage (soft callus) - 2-3 weeks
• osteoblasts lay down bone matrix (type 1 collagen) = echondral ossification
• calcium mineralisation produces immature woven bone (hard callus) - 6-12 weeks
• remodelling occurs with organisation along lines of stress into lamellar bone

Question 5

what is required for secondary bone healing to take place?

Answer 5

good blood supply for oxygen, nutrients and stem cells
a little movement/stress
nutrition
not smoking
can result in atrophic non union or hypertrophic non union without

Question 6

what are the 5 patterns of fracture?

Answer 6

transverse - due to bending force
oblique - due to shearing force (fall from height, deceleration)
spiral - due to torsional, rotational forces
comminuted - due to high energy injury
segmental - bone fractured in 2 separate places

Question 7

what are the features of each fracture type?

Answer 7

transverse - can angulate or cause rotational malalignment
oblique - tend to shorten and angulate, fixed with screw
spiral - rotational instability and can angulate, screws can be used
comminuted - 3 or more fragments, soft tissue swelling, periosteal damage, reduced blood supply, unstable, needs surgery
segmental - very unstable and need long rods or plates

Question 8

how can a fracture of a long bone be described?

Answer 8

site - proximal, distal, middle
type of bone - diaphyseal, metaphyseal, epiphyseal
intra/extra-articular
displacement

Question 9

what does displacement of a fracture depend on?

Answer 9

translation
angulation
rotation

Question 10

how can translation of a distal fragment be describe?

Answer 10

anteriorly or posteriorly displaced
medially or laterally translated
- terms replaced by volar/palmar and radial/ulnar when in the hand
degree estimated with reference to width of bone

Question 11

what is a 100% displacement of fracture known as?

Answer 11

off ended fracture

Question 12

what is angulation?

Answer 12

the direction in which the distal fragments points towards and the degree of this deformity

Question 13

how is angulation described?

Answer 13

medial/lateral and anterior/posterior
radial/ulnar and dorsal/volar in upper limb
varus/valgus and in lower limb
measured in degrees from the longitudinal axis of diaphysis of long bone

Question 14

why is angulation important?

Answer 14

gives info about direction of forces, reversed direction of forces required to reduce the fracture
can lead to deformity, loss of function and post traumatic OA

Question 15

what is rotational malalignment?

Answer 15

rotation of the distal fragment relative to the proximal fragment
unstable and needs to be corrected

Question 16

what are the clinical signs of a fracture?

Answer 16

localised bony tenderness
swelling
deformity
crepitus - from bone ends grafting with unstable fracture

Question 17

general rule for X ray of possible fracture?

Answer 17

if patient cant weight bear on an injured lower limb - request an X ray

Question 18

how do you assess an injured limb?

Answer 18

open or closed
neurovascular status
presence of compartment syndrome
assess skin and soft tissue envelope

Question 19

how can a fracture be investigated?

Answer 19

radiograph - 2 views always requested (AP and lateral/sometimes oblique)
tomogram - moving x ray, used for mandibular fractures
CT - complex bones/fractures, show articular damage, surgical planning
MRI - if normal x ray
Technetium bone scans - stress fractures (don’t show in X ray)

Question 20

describe the initial management of a long bone fracture

Answer 20

clinical assessment
analgesia
splintage/immobilization (backslab, sling, orthosis, Thompson splint)
investigation
reduce before X ray if grossly displaced or risk to skin

Question 21

describe definitive management of undisplaced or minimally displaced/angulated fractures

Answer 21

non-operative with splintage or immobilization then rehab

Question 22

how are displaced or angulated fractures managed definitivey

Answer 22

reduction under anaesthesia
closed reduction and cast application
surgical stabilisation (plates, screws, pins, nails, external fixation etc)

Question 23

how is an unstable extra-articular diaphyseal fracture managed?

Answer 23

can be fixed with ORIF using plates and screws

Question 24

when should ORIF be avoided and what is used instead in such a case?

Answer 24

soft tissue swelling
high energy blood supply
if ORIF would cause blood loss (femoral shaft)
if plate fixation at the site would be prominent (tibia)
instead closed reduction and indirect internal fixation with intramedullary nail

Question 25

what methods of fracture healing cause primary and secondary healing?

Answer 25

ORIF = primary closed reduction with intramedullary nail = secondary external fixation = secondary

Question 26

how are displaced intra-articular fractures managed?

Answer 26

require anatomic reduction and rigid fixation by way of ORIF with wires, screw and plates

Question 27

how are fractures involving a joint with predicted poor outcome managed?

Answer 27

joint replacement or arthrodesis

Question 28

why are older patients often treated non-operatively?

Answer 28

co morbidities higher surgery complication risks less satisfactory rehab results lower functional demand

Question 29

how can fracture complications be categorised?

Answer 29

early/late | local/systemic

Question 30

what are some early local complications?

Answer 30

compartment syndrome vascular injury - ischaemia nerve compression skin necrosis

Question 31

what are some early systemic complications?

Answer 31

``` hypovolaemia fat embolism shock ARDS renal failure multi organ dysfunction systemic inflammatory response syndrome death ```

Question 32

what are some late local complications?

Answer 32

``` stiffness loss of function chronic pain infection non union mal union volkmanns ischaemic contracture OA DVT ```

Question 33

what is the main late systemic complication?

Answer 33

PE

Question 34

what are the symptoms of compartment syndrome?

Answer 34

severe pain on passive stretching of involved muscle severe pain more than expected in clinical context paraesthesia and numbness swelling tenderness loss of pulse at end stage

Question 35

management of compartment syndrome?

Answer 35

remove any tight bandages | emergency fasciotomy - leave open for a few days then secondary closure/skin graft

Question 36

complication of compartment syndrome?

Answer 36

volkmanns ischaemic contracture | ischaemic muscle with necroes resulting in fibrotic contracture

Question 37

what can happen to vessels in fractures?

Answer 37

``` stretched compressed torn transected partial tear > thrombosis > arterial occlusion ```

Question 38

give some possible complications of vascular injury

Answer 38

ischaemia - amputation | hypovolaemic shock

Question 39

what injuries are most likely to cause vascular injury?

Answer 39

``` penetrating injury knee dislocation paediatric supracondylar fracture shoulder trauma pelvic fractures ```

Question 40

how can temporary restoration of circulation be achieved?

Answer 40

vascular shunt vascular repair with bypass graft or endoluminal stent skeletal stabilisation with internal/external fixation to protect repair

Question 41

what is done for an ongoing haemorrhage from artery injury in pelvis?

Answer 41

angiographic embolization

Question 42

what skin sign can indicate that an emergency reduction of a fracture is needed and why?

Answer 42

tenting of skin and blanching protrusion through skin to avoid subsequent necrosis

Question 43

what causes degloving and what are the features of this?

Answer 43

shearing force on the skin causing avulsion of the skin from its blood vessels skin wont blanch on pressure and have no sensation can have an underlying haematoma increasing pressure on skin and occluding capillaries

Question 44

what is a fracture blister?

Answer 44

inflammatory exudate causes lifting of the epidermis of the skin (like burn)

Question 45

why is surgery not preferred which soft tissue is swollen?

Answer 45

wound may not be able to close or if it does it may be very tight and the tension can lead to necrosis and wound breakdown

Question 46

what are the signs of fracture healing?

Answer 46

resolution of pain and function absence of point tenderness no local oedema resolution of movement at fracture site

Question 47

what are the signs of non union?

Answer 47

ongoing pain and oedema movement at fracture site bridging callus seen on imaging

Question 48

what is delayed union and what can cause it?

Answer 48

fracture that doesn't heal within expected time | can be caused by infection

Question 49

what are the 2 types of non-union and what causes them?

Answer 49

hypertrophic - instability, excessive motion, infection | atrophic - rigid fixation with gap, poor blood supply, chronic disease, soft tissue interposition, infection

Question 50

name some fractures which are prone to non-union?

Answer 50

``` scaphoid distal clavicle subtrochanteric femur jones fracture some intra-articular fractures ```

Question 51

what is fracture disease?

Answer 51

stiffness and weakness due to the fracture and subsequent splintage fixed with physio

Question 52

bones prone to AVN? how are they managed?

Answer 52

femoral neck scaphoid talus THR or arthrodesis

Question 53

what type of fracture causes post traumatic OA?

Answer 53

intra-articular fracture malunion ligamentous instability

Question 54

what is chronic regional pain syndrome?

Answer 54

``` heightened chronic pain after injury constant burning/throbbing sensitivity to non-painful stimuli chronic swelling stiffness painful movement skin colour changes ```

Question 55

what can cause CRPS and how is it managed?

Answer 55

Type 1 = unknown Type 2 = peripheral nerve injury management = pain relief (analgesics, nerve block, antidepressants, anti epileptics)

Question 56

how does infection affect fracture healing?

Answer 56

slows it down when active | fracture can unite when infection is suppressed

Question 57

how is infected fracture fixation managed?

Answer 57

antibiotics and surgical washout if present for longer than a few weeks - metal needs removed if infection cant be suppressed - remove all implants and debride infected bone

Question 58

management of medullary infection?

Answer 58

medullary canal reamed out and a new nail implanted or external fixator

Question 59

management of infected non-union of a plate and screw fixation?

Answer 59

external fixator