C-Spine InjuryC-Spine Injury

Radiology ChallengeRadiology Challenge

AdequacyAdequacy

Skull baseSkull base C1-C7C1-C7 Upper T1Upper T1

AlignmentAlignment

Anterior spinal lineAnterior spinal line Posterior spinal linePosterior spinal line Spinolaminal lineSpinolaminal line Spinous process tipsSpinous process tips

BonesBones

Anterior componentsAnterior components– Vertebral body (cortices, endplates)Vertebral body (cortices, endplates)– Transverse process Transverse process

Posterior componentsPosterior components– Articular masses and pediclesArticular masses and pedicles– Facet jointsFacet joints– LaminaLamina– Spinous processSpinous process

CartilageCartilage

Intervertebral discsIntervertebral discs Epiphyses (childhood)Epiphyses (childhood)

– Subdental synchondrosisSubdental synchondrosis Ossification centers (childhood)Ossification centers (childhood)

– Tapered anterior vertebraeTapered anterior vertebrae– Absent C1 anterior ringAbsent C1 anterior ring

Soft TissueSoft Tissue

CervicocranialCervicocranial– Pd : Adenoid hypertrophyPd : Adenoid hypertrophy

PredentalPredental– Ad : < 3mmAd : < 3mm– Pd : < 5mmPd : < 5mm

PrevertebralPrevertebral– Ad : C3 < 5-7mm; C5 < 15-21mm (1 body)Ad : C3 < 5-7mm; C5 < 15-21mm (1 body)– Pd : C3 < 7mm; C5 < 14mm (2/3 body)Pd : C3 < 7mm; C5 < 14mm (2/3 body)

Mechanism of InjuryMechanism of Injury

Types of c-spine injuriesTypes of c-spine injuries– Axial loadingAxial loading– FlexionFlexion– ExtensionExtension– RotationRotation– Lateral bendingLateral bending– Distraction.Distraction.

Jefferson fracture (C1) Jefferson fracture (C1)

Blowout of the ring Blowout of the ring Axial loadingAxial loading Open-mouth (odontoid) viewOpen-mouth (odontoid) view 1/3 associated with C-2 fracture1/3 associated with C-2 fracture UnstableUnstable Usually not associated with cord injuryUsually not associated with cord injury Lateral offset of C1 lateral masses > 1mm frLateral offset of C1 lateral masses > 1mm fr

om C2 vertebral bodyom C2 vertebral body

Pseudo-Jefferson fracturePseudo-Jefferson fracture

Age < 4YAge < 4Y 90% (+) at 2 Y90% (+) at 2 Y C1 growth > C2; radiolucent cartilageC1 growth > C2; radiolucent cartilage Normalizes by 4-6 YNormalizes by 4-6 Y CT scan neededCT scan needed

C-1 Rotary SubluxationC-1 Rotary Subluxation

Odontoid not equidistant from lateral massesOdontoid not equidistant from lateral masses ChildrenChildren Torticolis (chin toward uninvolved side)Torticolis (chin toward uninvolved side) Immobilize in placeImmobilize in place Consult NSConsult NS

C-2 Odontoid SubluxationC-2 Odontoid Subluxation

Ruptured transverse ligamentRuptured transverse ligament Odontoid fracturesOdontoid fractures Predental space :Predental space :

– Ad > 3mmAd > 3mm– Pd > 5mm (symptomatic if > 7-10mm)Pd > 5mm (symptomatic if > 7-10mm)

C1 spinal canal (Steel rule of 3) :C1 spinal canal (Steel rule of 3) :– Odontoid – Free space – CordOdontoid – Free space – Cord

UnstableUnstable

C2 Odontoid FracturesC2 Odontoid Fractures

Type I : Avulsion of tipType I : Avulsion of tip– StableStable

Type II : At the baseType II : At the base– UnstableUnstable– D/D : Synchondrosis if < 6YD/D : Synchondrosis if < 6Y

Type III : Through vertebral bodyType III : Through vertebral body– UnstableUnstable

Hangman FractureHangman Fracture

Traumatic spondylolisthesis of C2Traumatic spondylolisthesis of C2 Mechanism : Mechanism :

– Extension + DistractionExtension + Distraction– Extension + Axial compressionExtension + Axial compression

X-ray : C2/3 subluxationX-ray : C2/3 subluxation UnstableUnstable Traction contraindicatedTraction contraindicated

C2/3 SubluxationC2/3 Subluxation

C2 posterior spinal line v.s. Swischuk lineC2 posterior spinal line v.s. Swischuk line

Pseudosubluxation (< 8-16Y) :Pseudosubluxation (< 8-16Y) :– Displacement < 1.5-2 mmDisplacement < 1.5-2 mm

Hangman fracture :Hangman fracture :– Displacement > 1.5-2 mmDisplacement > 1.5-2 mm

Unstable FracturesUnstable Fractures Overriding of vertebra by > 3 mmOverriding of vertebra by > 3 mm Angulation > 11 degreesAngulation > 11 degrees Flexion teardrop Flexion teardrop Bilateral facet dislocation (BFD)Bilateral facet dislocation (BFD) Atlanto-occipital dislocationAtlanto-occipital dislocation Atlanto-axial dislocation (flexion/extension/rotary)Atlanto-axial dislocation (flexion/extension/rotary) Odontoid fractureOdontoid fracture Jefferson fracture/posterior arch fracture of C1Jefferson fracture/posterior arch fracture of C1 Hangman fractureHangman fracture

Stable FracturesStable Fractures

Wedge fractureWedge fracture Clay shoveler fractureClay shoveler fracture Transverse process fractureTransverse process fracture Unilateral facet dislocation (UFD)Unilateral facet dislocation (UFD) Burst vertebral bodyBurst vertebral body Isolated fracture of articular pillarIsolated fracture of articular pillar Extension teardrop in flexionExtension teardrop in flexion

SubluxationSubluxation

Angulation between two adjoining vertebraAngulation between two adjoining vertebrae >e > 11 degrees11 degrees

Overriding of vertebra by > 3 mmOverriding of vertebra by > 3 mm

Facet DislocationFacet Dislocation

Unilateral (UFD) : Unilateral (UFD) : – StableStable– < 25% translation< 25% translation

Bilateral (BFD) :Bilateral (BFD) :– UnstableUnstable– > 50% translation> 50% translation

Teardrop FracturesTeardrop Fractures

Extension teardrop :Extension teardrop :– Stable in flexion, unstable in extensionStable in flexion, unstable in extension– Cortices : Same lengthCortices : Same length

Flexion teardrop :Flexion teardrop :– Extremely unstableExtremely unstable– Cortices : Unequal lengthCortices : Unequal length

Hyperextension InjuryHyperextension Injury

Fracture of inferior endplate, being avulsed Fracture of inferior endplate, being avulsed by the Sharpey fibersby the Sharpey fibers

Extension teardropExtension teardrop Bilateral facet dislocation (BFD)Bilateral facet dislocation (BFD) Severe prevertebral soft tissue swellingSevere prevertebral soft tissue swelling Anteriorly displaced NG tubeAnteriorly displaced NG tube

Burst Vertebral BodyBurst Vertebral Body

Mechanically stableMechanically stable Spinal cord injury can occur (even total tranSpinal cord injury can occur (even total tran

section)section)

Distraction InjuriesDistraction Injuries

Longitudinal stress (e.g. difficult delivery)Longitudinal stress (e.g. difficult delivery) Atlanto-occipital dislocationAtlanto-occipital dislocation

– Increased space between occiput and C1Increased space between occiput and C1 Widening of IV disk without adjacent compWidening of IV disk without adjacent comp

ression fractureression fracture MRIMRI

Spinal EDHSpinal EDH

Venous bleedsVenous bleeds Minor traumasMinor traumas Ascending neurologic symptomsAscending neurologic symptoms Hours or daysHours or days MRIMRI

SCIWORASCIWORA

67% of pediatric SCI67% of pediatric SCI Mainly < 8 YMainly < 8 Y Plain films/tomograms/CT (-)Plain films/tomograms/CT (-) May have transient neurologic symptoms anMay have transient neurologic symptoms an

d apparently recover then return 1d later witd apparently recover then return 1d later with significant neurologic abnormalitiesh significant neurologic abnormalities

Poor prognosisPoor prognosis

SCIWORASCIWORA

Etiology : Etiology : – Vascular injuries (occlusion, spasm, infarction)Vascular injuries (occlusion, spasm, infarction)– Ligamentous injuryLigamentous injury– Disc impingementDisc impingement– Incomplete neuronal destructionIncomplete neuronal destruction

Oblique C-spineOblique C-spine

PediclesPedicles Articular massArticular mass Intervertebral foramen Intervertebral foramen Transverse process Transverse process Laminae - aligned in the fashion of shinglesLaminae - aligned in the fashion of shingles