Di Imaging 2 Exam 1

What % of skull fractures are detected on xray?

10%

What is the preferred examination for a skull fracture?

CT

What is a blowout fracture?

fracture of the floor of the left orbit

What is a tripod fracture?

The Zygomatic bone is broken at its 3 articulations - orbital process, maxillary process, and zygomatic arch

What are the most common skull fractures?

linear

What is the most common type of fracture of the spine causes?

hyperflexion

What is the MC levels for spinal trauma?

C1-C2, C5-7, T12-L1

What is the set of Xrays for a suspected fracture?

Davis Series

What is considered traumatic for the Davis series?

<48 hrs

What is the proper order for the Davis series?

lateral

APOM

AP cervical

Lt and Rt obliques

flexion extension

swimmers

How do you evaluate vertebral instability?

3 column method

What would be an example of instability?

more than one column is disrupted

middle column is disrupted

What is considered a concerning RPI?

>7mm

What is considered a concerning RTI?

>22mm

What could a vacuum cleft disc indicate?

spinal trauma

What angle of flexion indicates spinal trauma?

11 degrees

What would be an unstable amount of body offset?

3.5mm

What are some radiographic features of severe sprain?

widening of interspinous distance

loss of parallelism between facet joints

horizontal displacement >3.5 mm

angular displacement >11 degrees

What is the time period for fracture healing?

slow 3-6 months

Body fxs heal more with ? while arch fxs heal more with ?

fibrosis

callus

What is the MC fracture of atlas?

posterior arch

What is the mechanism for posterior arch fracture?

hyperextension

What is the name of a bursting fractuer of C-1?

Jefferson's fracture

What is the mechanism of a Jefferson's fx?

axial compression injury

What will an APOM xray look like with a Jefferson's fracture?

overhang sign

What amount of overhang indicates a transverse ligament?

7 mm

What is the MC cause of a large ADI?

atlantodental interval

What view is best to fully evaluate the ADI?

lateral

What is Steele's rule of thirds?

1/3 cord

1/3 odontoid

1/3 potential space

What is a type I odontoid fracture?

tip of odontoid

What is a type II odontoid fracture?

fx at the base

What is a type III odontoid fracture?

fx into the body

What type of odontoid fx is unstable?

Type II

What type of fx would disrupt Harris' ring?

type III

What age is the upper most limit to have a normal secondary growth center at the odontoid tip?

12

Most os odontoideums are ?

old ununited dens fx

What is another name for a Hangman's fx is?

a traumatic spondylolithesis of C2

What is the mechanism for a hangman's fx?

hyperextension

What is the mc location for a 1st time cause of spondylothesis?

hangmans fracture

What is the mechanism for a compression fx?

flexion

What is the mechanism for a burst fx?

axial

What is the most serious cervical injury?

flexion teardrop

What is the mechanism for a flexion teardrop?

flexion and axial injury

What sets apart a new compression fx from old?

New- step or sclerosis of superior endplate

New fractures look ? on T1

dark

T/F burst fractures are stable

false

What is the mechanism for a unilateral facet dislocation?

flexion rotation

What is the sign for unilateral facet dislocation?

bow tie sign

With unilateral facet dislocation, the spinous rotates ? the side of dislocation

toward

What are the 3 signs seen with unilateral facet dislocation?

bow tie sign

anterior displacement

decreased laminar length

What is the mechanism for bilateral facet dislocation?

hyperflexion

What levels are mc for bilateral facet dislocation?

C4-C7

When both facets go anterior with dislocation this is called?

interlocking facets

A surgical fixation is called ?

surgical arthrodesis

What does a flexion teardrop look like on radiograph?

anterior triangle; increased spinous space; facet dislocation and widening

What is the mechanism for an extension teardrop fracture?

extension

What level normally has an extension teardrop fx?

C2

What levels are Clay Shoveler's fractures found at?

spinous fx at C-7, C-6, T-1

What is the mechanism for a Clay shoveler's fx?

flexion

What may be seen on an AP xray with a clay shoveler's fx?

double spinous

Except for Clay shoveler's fx, what is the mechanism for all other spinous fx?

extension

Hyperflexion associated with whiplash disrupts ?

post ligament complex

What are radiographic features of a severe sprain?

fanning of spinouses

loss of parallelism

horizontal displacement

angular displacement

Where do most thoracic or lumbar fx take place?

between T11 and L2

What are causes of pathological fx?

osteoporosis

lytic mets

multiple myeloma

eosinophilic granuloma (kids)

What is seen with the body of bursting compression fxs?

posterior body convexity

A ghost vertebra sign is seen with ?

chance fx

What levels are most likely to have a chance fx?

L1-L3

What is the 2nd mc lumar fx?

transverse process fx

An interruption of the pars is a ?

spondylolysis

an anterior displacement with an interruption of the pars is ?

spondylolisthesis

A spondylolysis without anterior displacement is a ?

psuedospondylolisthesis

An anteriority w/o pars defects is a ?

pseduospondylolisthesis

What are the wiltse classification for spondylolisthesis?

I: dysplastic

II: spondylolytic

III: degenerative

IV: traumatic

V: pathological

VI: post surgical

What can cause a congenital spondylolisthesis?

malformation of sacrum and L-5

What is the MC cause of a spondylolytic spondylolisthesis?

stress fx

Which age is mc to have a spondylolytic spondy?

younger

What level is most likely to have a degenerative spondylo? spondylolytic?

degenerative- L4

spondylolytic- L5

What is the most likely traumatic spondylo?

Hangmans fx

What are some causes of pathologic spondys?

mets, Pagets. osteopetrosis

What detects spondys? What grades spondys?

detect- George

grade- meyerding

What does a Grade IV L5 spondy look like on radiograph?

inverted napolean hat

What are some causes of increased density on L5?

blastic mets

facet arthrosis

primary bone tumor

missing ped on contra

pars defect on contra

What can cause sacral fx?

direct trauma or fall on butt

Most sacral fx are ? in orientation

horizontal

A stable pelvic fx is ?

a single break

An unstable pelvic fx is ?

2 breaks of the ring

A fracture of the iliac wing is a ?

duverney fx

What is the Mc fx of the pelvis?

ischiopubic rami fx

An avulsion fx of the ischial tuberosity is from ?

hamstring

An avulsion fx of the AIIS is from the ?

rectus femoris

An avulsion fx of the ASIS is from the ?

sartorius

An ipsilateral double shearing fx fo the pubic rami w a fracture or dislocation of the ipsilateral SI is a ?

Malgaigne fx

A contralateral double shearing fx to the pubic rami with a contralateral SI fx or dislocation is a ?

bucket handle fx

Bilateral superior and inferior rami fx are ?

straddle fx

diastasis of the pubic symphysis is a ? pelvis

sprung/ open book

What mm of divergence of the pubic symphysis is considered diagnostic?

10