(1,3) TL Fractures Flashcards
(54 cards)
What theory is used to determine stability of TL spinal fractures?
3 column theory of Denis
What makes up the anterior column of the TL spine?
anterior 2/3 of vertebral body
What makes up the middle column of the TL spine?
posterior 1/3 of vertebral body
What makes up the posterior column of the TL spine?
posterior elements
According to the 3 column theory of Denis, when is a fracture considered stable?
if only 1 column is affected
(eg. compression Fx = ant column)
According to the 3 column theory of Denis, when is a fracture considered unstable?
2 or more columns involved (eg. burst fx, chance fx)
Which column of the TL spine cannot fracture by itself? Is this stable or unstable?
middle column = unstable
What is the one exception to the middle column rule regarding TL spine stability?
traumatic posterior limbus bone
What is the stability of a fracture that involves the anterior column only, but greater than 50% vertebral body height is lost?
probably unstable
What populations do compression fractures occur most in?
- 35%: F, >45, w/ postmenopausal osteoporosis
- 30%: secondary osteoporosis
- 25%: acute trauma (otherwise healthy)
What are the possible mechanisms of a compression fracture?
- osteoporosis w/ minor trauma
- insufficiency fx
- acute trauma: hyperflexion and/or axial load
What are the most common sites of compression fractures?
T11-L1
What is the typical shape of a thoraco-lumbar compression fracture?
wedge-shaped
What are the possible shapes of lower lumbar compression fractures?
- wedge
- central endplate fx
- biconcave “fish”
What population are lower lumbar compression fractures common in?
older females
What structures are damaged with a biconcave (fish) shaped compression fracture?
Fx of both sup + inf endplates
What mechanism is indicated by vertebra plana?
pathologic (not traumatic)
What are the 3 most important imaging characteristics to determine a new versus old compression fracture?
New Fx may have:
- zone of impaction
- step defect
- paraspinal edema
(if 1 of 3, likely acute)
When is paraspinal edema visible on x-ray?
- compression Fx of T12 or above
- AP t/s view
What is a zone of impaction?
faint white line on x-ray along compression Fx line
What is the stability of a TL compression fracture?
stable
What is your next step if your patient has a compression fracture?
refer to orthopedist for pain control
Name an indirect indicator of a new compression fracture.
abdominal ileus
(^pain -> ^sympathetic tone + deactivated PSNS -> bowel fills w/ gas due to ^methanogenic bacteria breaking down food)
Name an indirect indicator of an old compression fracture.
Degenerative disc disease (wedge-shaped, osteophytes, less disc space)
(injured jt = ^DJD w/in 2 yrs)
