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Flashcards in Part 1 Deck (57)
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1
Q

Should we take xrays of the skull?

A

No, less than 10% of skull fractures are detected on xray
skull anatomy is very complex
interpretation is very difficult

2
Q

what does the patient need if you suspect a skull fracture?

A

CT

3
Q

tripod fracture

A

when all 3 major attachments of the zygoma are separated from the rest of the face

4
Q

what are the requirements for spine trauma xrays?

A

xrays must be of diagnostic quality
need appropriate views
old films can be helpful

5
Q

what are the different mechanisms of trauma?

A
hyperflexion**
hyperflexion and rotation
hyperextension
hyperextension and rotation
vertical compression
lateral flexion
6
Q

what are the different types of hyperflexion injuries?

A
compression fracture
bilateral interfacial dislocation
flexion teardrop fracture
clay shoveler's fracture
anterior subluxation
dens fracture
7
Q

what are the types of hyperflexion and rotation injuries?

A

unilateral interfacetal dislocation

unilateral interfacetal fracture-dislocation

8
Q

hyperextension fractures

A
avulsion of anterior tubercle of C1
hyperextension fracture-dislocation
hyperextension dislocation
posterior arch fracture of C1
extension teardrop fracture
hangman's fracture
lamina fracture
dens fracture
9
Q

hyperextension rotation fractures

A

pillar fracture

pedicolaminar fracture

10
Q

vertical compression fractures

A

jeffersons fracture of C1

bursting fracture of lower cervical spine

11
Q

lateral flexion fractures

A

unilateral fracture, lateral mass of C1
transverse process fracture
uncinate fracture

12
Q

where are the most common spinal traumas?

A

C1-2
C5-7
T12-L1

13
Q

what percentage of cervical traumas end up with neurological injury?

A

40%

14
Q

what percent of spinal traumas end up with spinal cord injuries overall?

A

10-14%

15
Q

what percent of thoracolumbar traumas end up with neurological injury?

A

10%

16
Q

if you suspect cervical spine trauma, what should you do?

A

take a 7 view cervical spine series

“Davis series”

17
Q

what is included in the 7 view cervical spine series?

A
lateral
APOM
AP cervical
right and left obliques
flexion and extension
swimmers
18
Q

what should you do if you have a diagnosis before you finish the entire 7 view cervical series?

A

stop and take care of it

19
Q

when is a fracture stable or unstable?

A

unstable: middle column, 2 or more columns
stable: anterior column only, posterior column only

20
Q

what if you have a new spinal fracture?

A

orthopedic consult

21
Q

how do you treat a stable injury?

A

more conservatively

22
Q

retropharyngeal space

A

7mm

23
Q

retrotracheal space

A

22mm

24
Q

signs of spine trauma (abnormal vertebral alignment)

A
misalignment
loss of lordosis
acute kyphotic angulation
widened interspinous spaces
vertebral rotation
torticollis
25
Q

signs of spine trauma (abnormal joints)

A

increased ADI
abnormal disc height
widened apophyseal joints

26
Q

other signs of spinal trauma

A

vacuum cleft disc
an angle of 11 degrees or more of flexion compared to adjacent levels
greater than 3.5mm body offset maybe a clue to instability

27
Q

radiographic features of severe sprain

A

widening of interspinous distance
loss of parallelism between facet joints
horizontal displacement
angular displacement of greater than 11 degrees compared to adjacent interspaces

28
Q

antero/retrolisthesis can be due to:

A
fracture
dislocation
ligamentous laxity
DJD
anatomic
physiologic
29
Q

how fast can spinal fractures heal?

A

3-6 months

30
Q

body fractures heal more with..

A

fibrosis

31
Q

arch fractures heal more with

A

callus

32
Q

posterior arch fracture

A

MC fracture of atlas
usually bilateral and vertical in orientation
hyperextension mechanism

33
Q

other name for jefferson’s fracture

A

bursting fracture of C1

34
Q

what is jefferson’s fracture?

A

axial compression injury
bilateral fracture of anterior and posterior arches
bilateral lateral mass offset

35
Q

when is a jefferson’s fracture definitely unstable?

A

when the transverse ligament is torn (>7mm)

36
Q

when is ADI most common

A

RA

37
Q

traumatic rupture is ___in ADIs

A

rare

38
Q

ADIs are considered..

A

unstabile

39
Q

what do you do when you find an increased ADI?

A

DON’T adjust

orthopedic consult

40
Q

what are the max ADIs for children and adults?

A

children: 5mm
adults: 3mm

41
Q

what are some etiologiesfor ADIs

A
normal variant
trauma
down's syndrome
major UC anomaly
inflammatory arthropathies
42
Q

what should you do if there is an increase in ADI

A

take flexion and extension films

43
Q

which film is better for seeing ADIs, flexion or extension?

A

flexion

44
Q

steele’s rule of thirds

A
ring of atlas is
1/3 cord
1/3 odontoid
1/3 potential space
anterior displacement may be asymptomatic
45
Q

40-50% of axis fractures are..

A

dens fractures

46
Q

name the types of odontoid fractures and how common they are

A

type I: oblique fx of the tip (4%)
type II: fx at the base (66%)
type III: fx into the body 30%)

47
Q

type I dens fractures are stable or unstable?

A

stable and rare

48
Q

type II dens fractures are stable or unstable?

A

unstable and most common

49
Q

type III dens fractures are stable or unstable?

A

unstable when broken

stable when healed

50
Q

which dens fracture are non unions common?

A

type II

51
Q

what is disrupted with type III dens fractures?

A

Harris’ ring

52
Q

describe type I dens fx

A

uncommon
avulsion of the tip
distraction by apical or alar ligament

53
Q

describe type II dens fx

A

transverse or oblique fx through base
best seen on APOM
nonunion very cmmon
unstable

54
Q

if the dense is more than 5mm displaced in a type II dens fx, what does that mean?

A

100% nonunion

55
Q

T/F: most os odontoideum are old ununited dens fx

A

true

56
Q

T/F: most old ununited dens fx are os odontoideums

A

false

57
Q

describe type III dens fractures

A
below junction of dens and C2 body
mechanically unstable
may disrupt Harris' ring
altered body contour "fat C2 body"
best seen on lateral
may need specialized again