Thoraco-Lumbar Radiography - rEMERGs

billowycookieUrban and Civil

Nov 29, 2013 (3 years and 8 months ago)

83 views

Thoraco
-
Lumbar

Radiography

Moritz Haager

March 4, 2004

Anatomy

Thoracic Spine

Lumbar Spine

Determinants of Stability

T & L spines are more stable than C
-
spine


Strong ligaments


Stabilization by ribs


Bigger intervertebral discs


Larger facet joints


Less mobility

Fractures & dislocations tend to occur where
curvature changes


T11
-
12 (thoracolumbar junction)


L5
-
S1 (lumbosacral junction)

Mechanisms of Injury

Hyperflexion +/
-

rotation


Commonest


Usually see anterior wedge #’s or Chance #

Shearing


Ant or post translation

Hyperextension

Axial loading


Compression or burst #’s

3 Column Model

Anterior column


Ant longitudinal lig


Ant annulus fibrosis


Ant vertebral body

Middle column


Post longitudinal lig


Post annulus fibrosis


Post vertebral body

Posterior column


Spinous processes


Transverse processes


Lamina


Facet joints


Pedicles


Post ligamentous complex


2 or more columns disrupted =
unstable

Most disruption of middle columns are
unstable

Stable or Unstable?

Radiographic findings suggestive of instability


Vertebral body collapse w/ widening of pedicles


> 33% canal compromise on CT


> 2.5 mm translation b/w vertebral bodies in any
plane


Bilateral facet dislocation


Abnormal widening b/w spinous processes or lamina
and > 50% anterior collapse of vertebral body

Stable or Unstable?

Checklist for Instability


Anterior elements disrupted



2 pts


Posterior elements disrupted


2 pts


Saggital plane translation > 2.5 mm

2 pts


Saggital plane rotation > 5
o



2 pts


Spinal cord or cauda equina damage

2 pts


Disruption of costovertebral articulations

1 pt


Dangerous loading anticipated


2 pts



5 or more pts unstable until healed or surgically
stabilized

Stable or Unstable?

Risk of neurologic
injury increases with


> 35% canal
narrowing at T11
-
12


> 45% canal
narrowing at L1


> 55% canal
narrowing at L2 &
below

Approach to T & L Spines

A


adequacy & alignment


All vertebrae need to be visible


Ant & post longitudinal lines


Facet joints should lie on smooth curve


Normal kyphosis & lordosis


All spinous processes should lie in straight line

B


bones


Trace cortical margins of each vertebrae


Difference b/w ant & post body ht
<

2 mm


Progressive increase in vertebral body ht moving
down spine


Wink sign & interpedicular distance


Don’t forget to look at transverse processes

Approach to T & L Spines

C


cartilage


Progressive increase in disc space moving
down spine (except L5
-
S1)


Facet joint alignment

S

soft tissue


Look at paraspinal stripe and prevertebral
space

Case 1

38 yo female brought to ED after being
backed over by car driven by boyfriend

Intoxicated; c/o back pain & demonstrating
the remarkable versatility of the F
-
word


Transverse process fractures

of L2
-
4

Significance of transverse process

fractures is not the fractures in and

of themselves but rather the high

incidence of associated serious

intraabdominal injury (~20%)

Case 2

46 yo male presents to ED after falling 12
feet off ladder while putting up Christmas
lights c/o back pain

Anterolisthesis

Of L4 on L5

CT demonstrates chronic anterolisthesis with no intrusion into

spinal canal

Case 3

50 yo male again 10
-
12 foot fall off ladder
while putting up Christmas lights
(dangerous hobby)

Mild ant wedging of

T3 & T4

Mild ant wedging of

T3 & T4

Case 4

21 yo belted passenger in rollover single
vehicle MVA at highway speed

Widened paraspinal

line suggesting

hematoma

Laterally displaced

T5 pedicle

Anterior wedging of T4 & T5

w/ loss of 30
-
40% of body ht

Case 5

29 yo driver offroading in pick
-
up truck


rolls it at speed

Not belted, ejected from vehicle and
trapped underneath for 3 hrs

Paramediastinal

soft tissue density

& widening

Suggestive of

compression

fractures

Case 6

22 yo male single vehicle rollover. Not
restrained


ejected through windshield at
highway speeds

Comminution &

anterior wedging

of L2 w/ 50% loss

of body Ht

Posterior displacement

Involvement of pedicles &

laminar arch

CT demonstrates severe burst #

w/ horizontal plane extending

posteriorly through pedicles

and transverse processes in keeping

w/ a
CHANCE

fracture

Case 7

58 yo roofer presents to ED unconscious
after plunging 12 feet onto concrete
through skylight

Schmorl’s

node

Compression fracture of L3

w/ no obvious post element

involvement