Cheung Part 6

Question 1

what is an open fracture

Answer 1

when broken bone is exposed through the skin

orthopaedic emergency

Question 2

what urgent things are required for an open fracture

Answer 2

tetanus and antibiotics

semi-urgent surgical debridement

Question 3

high energy fractures are associated with what

Answer 3

extensie soft tissue damage, leading to disruption of healing pathways
not necessarily seen on X-ray

Question 4

in high energy fractures what must be evaluated

Answer 4

other limbs and spine for occult injury

Question 5

during the physical exam for a fracture one must examine the skin for what

Answer 5

any breaks, regional joint stability, and nerve and vessels for injury

Question 6

what is normally seen on a physical exam of a fracture

Answer 6

tenderness, swelling, deformity, crepitation, and abnormal movement

Question 7

stress fractures may take how long to show up on an X-ray

Answer 7

1-4 weeks

Question 8

what is the most sensitive image modality for a fracture

Answer 8

MRI

Question 9

what are the principles of a fracture (4 R’s)

Answer 9

Recognition
Reduce- set bone straight
Retain- keep the reduction with cast or surgery)
rehab

Question 10

what bad things can come from a fracture (that aren’t emergencies

Answer 10

nonunion- bone does not heal

malunion- bone heals in unacceptable alignment

Question 11

what medical emergencies can arise from a fracture

Answer 11

compartment syndrome

nerve and vessel damage

Question 12

what is primary (intramembranous) fracture healing

Answer 12

rigid fixation from plates

direct healing with no callous

Question 13

what is secondary (enchondral) fracture healing

Answer 13

controlled motion (Rods, casts)
indirect formation of bone from uncommitted mesenchymal cells

Question 14

what are the three stages (and how long are the) of enchondral ossification

Answer 14

inflammatory (48hours)
reparative (8 weeks)
remodeling (1 year)

Question 15

what are the risk factors for nonunion fracture healing

Answer 15

smoking
infection
poor immobilization
malnutrition
NSAID
poor blood supply
high energy trauma

Question 16

what is an osteogenic bone graft

Answer 16

bone forming

only autologous bone graft contains viable osteoblasts

Question 17

what is osteoinductive bone graft

Answer 17

bone stimulation
encourages differentiation of mesenchymal cells into osteoblasts
BMP-2 and BMP-7

Question 18

what is osteoconductive bone graft

Answer 18

bone scaffold

cancellous allograft

Question 19

autografts from cancellous pelvis is what

Answer 19

osteogenic, osteoinductive, and osteoconductive

but PAINFUL

Question 20

what bone graft is osteogenic, osteoinductive, and osteoconductive

Answer 20

autograft from cancellous pelvis

Question 21

allografts are what kind of bone graft

Answer 21

conductive only

carry infection risk

Question 22

demineralized bone matrix are what kind of bone graft

Answer 22

osteoinductive

expensive and not conductive

Question 23

snythetic substitutes have what kind of bone graft

Answer 23

osteoinductive and osteoconductive
god compression strength
very expensive

Question 24

external ultrasound have have what effect on fracture healing

Answer 24

may improve healing potential

Question 25

what is an intra-articular fracture

Answer 25

involves joint surface needs perfect reduction early motion key

Question 26

what is an extra-articular fracture

Answer 26

does not involve joint surface | needs good overall alignment

Question 27

what are the pros of casting

Answer 27

undisturbed fracture milleu no incisions heals by endochondral ossification

Question 28

what is endochondrial ossification

Answer 28

cells differentiate into chondrocytes and lay down cartilage which calcifies, osteoclasts absorb cartilage and osteoblasts lay down new osteoid

Question 29

what are the cons to casting

Answer 29

no anatomic reduction | stiffness

Question 30

what are the pros to traction

Answer 30

doesn't disturb fracture mile | no risk of surgery

Question 31

what are the cons to traction

Answer 31

poor reduction pin site problems fracture disease

Question 32

what are the pros to external fixation

Answer 32

load bearing small incisions fracture milleu ok early motion

Question 33

what are the cons of external fixation

Answer 33

pin sites | pain in the ass

Question 34

what are the pros to intramedullary nailing

Answer 34

load bearing small incisions periosteal blood supply ok stimulates endosteal blood supply

Question 35

what are the cons to intramedullary nailing

Answer 35

not anatomic callus formation too much movement

Question 36

what are the pros to open reduction internal fixation (ORIF)

Answer 36

anatomic reduction load SHARING early motion heals with intramembranous ossification

Question 37

what is intramembranous ossification

Answer 37

undifferentiated cells become osteoclasts and lay down new osteoid

Question 38

what are the cons to open reduction internal fixation (ORIF)

Answer 38

stripping increases nonunion | bigger wounds

Question 39

what are the pros to ORIF locked

Answer 39

``` load BEARING internal ExFix early motion less stripping smaller wounds good for poor bone quality ```

Question 40

what are the cons to ORIF locked

Answer 40

decreased healing due to lack of micro motion cost not anatomic reduction

Question 41

weight bearing status pros

Answer 41

quicker return to function | stimulates bone growth

Question 42

what are the cons to weight bearing status

Answer 42

may be more weight than fixation can handle

Question 43

what are the pros to movement

Answer 43

faster return to function decrease stiffness faster healing helps reduction of fractures

Question 44

what are the cons to moment

Answer 44

wound problems | may overwhelm fixation repair

Question 45

what type of fracture repair is load sharing

Answer 45

open reduction internal fixation (ORIF)

Question 46

what type of fracture repairs are load bearing

Answer 46

ORIF, locked external fixation intramedullary nail

Question 47

what is considered and internal ExFix

Answer 47

ORIF, locked

Question 48

what are the signs and symptoms of compartment syndrome

Answer 48

``` pain with passive stress pulselessness parasthesias palor cold/numb ```