Thoracic and Lumbar Trauma

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Thoracic and Lumbar Trauma
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Thoracic Compression Fracture

• M.C. at T11 and T12
• Hematoma may cause displacement of the paraspinal
  stripe on AP film
• Wedge shape vertebra on lateral film

http//orthoinfo.aaos.org/topic.cfm?topicA00538
http//download.imaging.consult.com/ic/images/S193
3033207730938/ gr3-midi.jpg
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Thoracic Fracture-Dislocation

• M.C. T4-T7
• Often associated with neurological damage because
  canal is small and blood supply is sparse
• Rad features include loss of
• vert. body height, displacement,
• widened interpediculate
• distance and widened paraspinal
• stripe
• Best appreciated on CT

http//www.ajronline.org/cgi/content-nw/full/187/4
/859/FIG12
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Lumbar compression Fractures

• M.C. fxs. of L/S L1 is m.c.
• In elderly, due to osteoporosis (insufficiency
  fx)
• Stability is determined based on Denis 3-column
  model
• Anterior- from ALL to mid-vertebral body
• Middle- from mid-vert. body to PLL
• Posterior- from PLL to supraspinous lig.
• Disruption of 2 or 3 columns implies instability
• Likelihood of neurological injury is high and
• interventional surgery is likely necessary

http//www.nrmedical.net/nrpd-xrayreporting.asp
http//www.radiologyassistant.nl/en/4906c8352d8d2
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Rad. Signs of Vert. Compression Fxs.

• Step defect- buckling of the anterior cortex,
  near the superior vertebral endplate on lateral
  view
• Wedge deformity- anterior depression of the
  vertebral body occurs, creating a triangular
  wedge shape
• Up to 30 or greater loss in anterior height may
  be required before the deformity is readily
  apparent on convention x-rays
• Normal variant anterior wedging of 10-15 or 1-3
  mm is common thought the T/S and most marked at
  T11-L2

http//www.ski-injury.com/specific-injuries/spinal
1
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Rad. Signs of Vert. Compression Fxs.

• Zone of Condensation- band of radiopacity below
  sup. Endplate represents the early site of bone
  impaction following a forceful flexion injury
  where the bones are driven together
• If present, denotes a fracture of recent origin
  (lt2 months duration)
• Paraspinal edema- U/L or B/L hemmorrhage may
  occur
• Displaces paraspinal stripe on AP T/S creates
  asymmetrical densities or bulges in psoas margins
  on AP L/S

http//download.imaging.consult.com/ic/images/ S19
33033207730938/gr3-midi.jpg
http//www.dynamicchiropractic.com/mpacms/dc/artic
le.php?id51049
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Rad. Signs of Vert. Compression Fxs.

• Abdominal ileus- seen radiographically as
  excessive amount of small or large bowel has in a
  slightly distended lumen
• Warns that the trauma was severe and fracture is
  likely
• Results from disturbance to the
• visceral autonomic nerves or
• ganglia from pain, paraspinal
• soft tissue injury, edema or
• hematoma

http//www.ganfyd.org/images/thumb/6/69/Axr_ileus.
jpg/ 180px-Axr_ileus.jpg
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Old Vs. New Compression Fracture

• Previously mentioned signs disappear with
  healing, which could be up to 3 months in adult
• DJD develops due to altered mechanics
• MRI reveals bone marrow edema with recent
  fracture up to 6 weeks post
• trauma

http//www.dynamicchiropractic.com/mpacms/dc/artic
le.php?id51049
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Burst Fractures

• Compression fracture where posterosuperior
  fragment is displaced into the spinal canal
• Neurological injury in up to 50 of cases (best
  demonstrated by MRI or CT)
• AP film shows vertical fracture line, which
  differentiates from simple wedge comp. fx.
• Widening of the interpediculate distance
  signifies a fracture within the neural arch
• Acquired coronal cleft vertebra coronally
• oriented fracture the separates the
• vertebral body into anterior and posterior
• halves
• Central depression of the superior and
• inferior endplates occurs with
• comminution of the vertebral body

http//radiopaedia.org/images/11020
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Burst Fractures
http//www.medscape.com/content/2004/00/48/20/4820
43/482043_fig.html
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Posterior Apophyseal Ring Fractures

• Separation of the posterior vertebral body ring
  apophysis (posterior limbus bone) is a relatively
  uncommon abnormality
• Most common levels are L4/5 and L5/S1
• 50 are caused by trauma, such as weightlifting,
  MVAs, gymnastics
• Between 15 and 20 are visible on lateral
  radiographs, but CT is definitive
• Surgery may be warranted after failure of
  conservative care and in the presence of
  significant
• neurological compromise

http//www.sciencedirect.com/science/article/pii/S
089970711200037X
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Kummels Disease

• Post- traumatic vertebral collapse, caused by
  rarefying process in vert. body months after
  trauma
• Results from complicating avascular necrosis
  resulting in progressive compression
• deformity
• Intravertebral vacuum
• phenomenon may be evident
• on radiographs

http//radiopaedia.org/cases/kummell-avn?fullscree
ntrue
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Fractures of the Neural Arch

• Transverse process fractures- 2nd m.c. L/S fx.
• Occur from avulsion of the paraspinal muscles,
  usually secondary to a severe hyperextension and
  lateral flexion blow to the L/S
• M.C. at L2 and L3
• Loss of the psoas shadow may occur secondary to
  hemorrhage
• Large forces involved, so organs may be damaged
  as well
• Pars interarticularis fractures- acute fxs
• (not stress fxs.) are rare
• Violent hyperextension of L/S, usually at L4 or
  L5
• Usually unilateral, not bilateral like stress fx.
• Heal without residual defects or anterior
• displacement

http//openi.nlm.nih.gov/detailedresult.php?img27
76377_JETS-02-217-g001querythefieldsallfavor
noneitnonesubnoneuniq0spnonereq4simColl
ection2762171_IJO-43-234-g001npos36prt3
http//www.sciencedirect.com/science/ article/pii/
S1529943011014033
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Chance or Lap Seat Belt Fracture

• Aka fulcrum fracture seat belt acts as fulcrum
  over abdomen
• Horizontal splitting of the spine and neural arch
• Internal visceral damage may occur rupture of
  the spleen or pancreas and tears of the small
  bowel and mesentery
• M/C location is upper L/S (L1-L3)
• AP radiograph shows transverse fracture through
  the posterior elements and angulation of the
  superior portion of the fractured vertebra
• The resulting widened radios gap between the two
  fractured segments has been turned empty vertebra
• Lateral radiographs shows radiolucent split
  through spinous process, lamina, pedicle and
  upper corner of the posterior aspect of the
  vertebral body

http//www.radiologyassistant.nl/en/4906c8352d8d2
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Fracture-Dislocation

• Usually at thoracolumbar junction after a violent
  flexion injury
• Avulsion fractures (teardrop) are commonly found
  associated with dislocation of the L/S
• Most dislocations are anterior in position,
  without lateral displacement
• Complete luxation with lateral shift of spine may
  create cord or cauda equina paralysis
• Axial CT shows absence of
• apposed articular facets
• (naked facet sign)

http//www.ajronline.org/content/187/4/859/F4.expa
nsion.html
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References

• Yochum, T.R. (2005) Yochum and Rowes Essentials
  of Skeletal Radiology, Third Edition. Lippincott,
  Williams and Wilkins Baltimore.