Spinal Trauma and Radiographic Assessment

Spinal trauma: general considerations

• C7 is the most frequently
• Common sites of # are CI-C2, C5-C6, T10-12
• In most spinal trauma, spinal cord damage occurs at time of injury
• AP, lateral views
• CT to clarify #s,

MRI for soft tissue injury

The spine

Spinal trauma: cervical spine

Examine the cross table lateral first, before doing other views to avoid moving pt, if the lateral is normal, then do the rest of the series When no # is seen on all views and pain is present, do flexion and extension laterals CT clarifies the injuries

Spinal trauma: cervical: reading a film

• All 7 vertebrae should be shown
• Check thickness of retropharyngeal space

Asses the 4 parallel lines for discontinuity or step-off Examine the atlantodental interval ( distance from anterior arch of C1 to odontoid process of C2 Scrutinize disc space for narrowing or widening

Spinal trauma cervical: 4 parallel lines

• Anterior vertebral line
• Posterior vertebral line
• Spinolaminar line
• Posterior spinous line

ODONTOID PROCESS OF C2 SHOULD ALIGN WITH THE CLIVUS

Anatomy of the cervical spine showing the 4 lines

Spinal trauma cervical:important measurements

• Thickness of soft tissue plane anterior to C1-C3 < 5mm

Thickness of soft tissue plane anterior to C4-C7 <20 mm Width of atlantodental interval < 3mm in adults and <5 mm in children (if wider impies torn transverse ligament)

Spinal trauma cervical : mechanisms

• Hyperflextion
• Hyperextension

compression

Spinal trauma cervical; common injuries

• Subluxation
• Locked facets (unilateral or bilateral)
• Odontoid fractures
• Wedge fractures
• Clay- shoveler’s #

Teardrop #

Spinal trauma cervical :extension injuries

• C1 posterior arch
• Hangmans #
• Extension teardrop#

Jefferson’s #( this is extension –compression)

Spinal trauma: unstable cervical fractures

• Bilateral locked facets
• Odontoid # type 2
• Teardrop
• Hangmans
• Jefferson

Burst #

Odontoid fractures

Jefferson #

• Commpression #
• Bony ring of C1
• Lateral mass is split, transverse lig. Is torn
• Axial force

See displaced lateral mass of C1 beyond lateral margins of C2

Hangman’s #

• Traumatic spondylolisthesis of axis’
• Hypersextension injury
• See bilatral pars interarticulatis #s of C2
• See anterior dislocation of C2 body
• See antero-inferior avulsion # associated with a torn anterior longt. Lig.

Prevertebral soft tissue shadow

Hangmans #

Flexion teardrop

• Severe flexion as when diving into shallow water
• Posterior lig. Disruption and anterior compression # of the vertebral body
• This is the most severe and unstable # of all spinal #s
• See anterior vertebral body avulsion resebling a tear drop
• See posterior vertebral body subluxation
• see # of spinous process
• See prevertebaral heamatoma associated with tear of ant.longtd. Lig

Seen cord compression from fragments

Flexion teardrop

Clay shoveler’s #

• # of a spinous process often seen C6-T1
• See spinous process #best seen on lateral view

Ghost sign (double spinous process of C6 or C7 due to displaced fractures spinous process

Unilateral locked facets

Rotation injury of cervical spine resulting into tear of apophyseal joint ligaments and facet joint disclocation, making them lock See widening of the disc space (“Bow tie” or “ Bat wing” appearance of the locked facets

Bilateral locked facets

• Due to extreme hyperflexion
• Complete anterior dislocation of the vertebral body
• High risk of cord injury
• See complete anterior dislocation of vertebrae
• Disrupted post.lontd. Lig an detachment of ant. Longtd.lig

Bow tie or bats wing appearance of locked facets

Anterior subluxation

• Disruption of post. Longtd. Lig complex from hyperextension
• May be stable or unstable
• Do basic views, plus flexion and extension views
• See fanning or widening of interspinous distance

Anterior displacement of vertebral body

Thoracic spine trauma

# classified into compression (caused by anterior or lateral flexion) and burst (caused by axial loading or acute flexion) Compression # appears as wedging of the vertebral body. It is typically stable # Burst # (#lines extend throught the vertebral body to involve at times the post elements. Fragments in the vertebral canal cause cord compression. See a communited vertebrae, look for fragments in canal, widened interpeduncular distances

Chance #

• Trabsverse splitting of the vertebral body and post elements
• All the columns, ant, mid and post of the spine are involved
• Neurological defects occur if there is associated disclocation
• Associated with abdominal organ injury

Common in MVI when using a lap belt only

Spinal fracture -dislocation

• Compression, distraction, and rotation injury
• Extremely unstable

associated with neurological and abdominal organ damage