1、1Cervical Spine fractures2 Cervical AnatomyBiomechanically SpecializedSupport of“large”Cranial massLarge range of motionFlexion/extensionAxial rotationUnique osteological characteristics3C1-AtlasNo body2 articular pillarsFlat articular surfaceVertebral artery foramen2 archesAnteriorPosteriorVertebra
2、l artery groove4Function The AtlasTransition zone between head and c-spineImportant anatomical pointsSuperior articular processes allow flex/extInferior articular processes are important for rotationNotch for vertebral artery is a common fracture site5C2 AnatomyDensEmbriological C1 bodyBase poorly v
3、ascularizedOsteoporoticFlat C1-2 jointsVertebral artery foramenaInferomedial to superolateral6Anatomy The AxisImportant transition point for forces within the c-spineImportant anatomical pointsSuperior and inferior articular processes are“offset”in the AP direction-due to different functions at each
4、 articulationPars interarticularis-due to this transition is a frequent fracture siteOdontoid process-the“pivot”for rotation7Anatomy The LigamentsAllow for the wide ROM of upper C-spine while maintaining stabilityClassified according to location with respect to vertebral canalInternal:Tectorial memb
5、raneCruciate ligament including transverse ligamentAlar and apical ligamentsExternalAnterior and posterior atlanto-occipital membranesAnterior and posterior atlanto-axial membranesArticular capsules and ligamentum nuchae8AtlantoAxial AnatomyAtlantoAxial AnatomyTectorial Membrane910AtlantoAxial Anato
6、myAtlantoAxial AnatomyocciputC1C2Tranverse LigamentC1-C2 jointAlar Ligament11AtlantoAxial AnatomyAtlantoAxial AnatomyTransverseLigamentFacet forOccipitalCondyle12AtlantoAxial AnatomyAtlantoAxial AnatomyVertebral Artery13APPROACH TO C-SPINE INJURIES Following trauma or complaint of neck painObtain la
7、teralAP,and odontoid viewsThe lateral view is only adequate if T1 can be visualizedIf there is any doubt of fracture or prevertebral swelling,obtain oblique views and consider CTAll patients with sign/symptoms of cord injury require MRI14Cervical ViewsAPOdontoidObliques15Swimmers View16LATERAL VIEW
8、1.Anterior vertebral line(anterior margin of vertebral bodies)2.Posterior vertebral line(posterior margin of vertebral bodies)3.Articular pillar(where superior and inferior articular processes of cervical vertebrae have fused on either or both sides)4.Spinolaminar line(posterior margin of spinal can
9、al)5.Posterior spinous line(tips of the spinous processes)17C1-C2Predental space(distance between posterior aspect of anterior arch of C1 and anterior aspect of odontoid process)should be 3mm In adult and less 5mm in childrenOr lessring sign of C218C3-C7Anterior spinal,posterior spinal and spinolami
10、nar lines:should be smooth lines Disc Spaces should be approximately same anterior narrowing=flexion injury.Widening=extension injuryFacet joints should be parallelInterspinous distance should decrease from C3 to C7Transverse process of C7 points downward and T1 UPWARDS INTERVERTEBRAL DISC SPACES 19
11、Prevertebral Soft TissueNasopharyngeal space(C1)-10 mm(adult)Retropharyngeal spaceC 2-C4(between posterior pharyngeal wall and anterior border of vertebrae).Retro tracheal space C5-7(space between posterior tracheal wall and anterior inferior body C6)c3-4 5mm from vertebral body is normalC4-7 20mm f
12、rom vertebral body is normal5mm 22mm 10mm2021AP ViewThe height of the cervical vertebral bodies should be approximately equal The height of each joint space should be roughly equal at all levels.Spinous process should be in midline and in good alignment.22Odontoid ViewAn adequate film should include
13、 the entire odontoid and the lateral borders of C1-C2.Occipital condyles should line up with the lateral masses and superior articular facet of C1.The distance from the dens to the lateral masses of C1 should be equal bilaterally.The tips of lateral mass of C1 should line up with the lateral margins
14、 of the superior articular facet of C2.The odontoid should have uninterrupted cortical margins blending with the body of C2.23Classification of Fractures of c-spine HYPERFLEXION INJURIES Flexion teardrop fracture Hyper flexion Strain Wedge Compression fracture Bilateral facet LockUnilateral facet di
15、slocationClay-shovelers fractureHyper extention injuries Hangman fracture Extention teardrop fracture laminar fracture Pillar fracture Posterior arch of c1 fracture FRACTURE DUE TO AXIAL LOADING Jefferson fracture Burst fracture OTHER INJURIES Odontoid fracture Rotational Injuries24HyperflexionDistr
16、action creates tensile forces in posterior columnCan result in compression of body(anterior column)Most commonly results from MVC and falls25CompressionResult from axial loadingCommonly from diving,football,MVAInjury pattern depends on initial head positionMay create burst,wedge or compression fxs26
17、HyperextensionImpaction of posterior arches and facet compression causing many types of fxslaminaspinous processespediclesWith distraction get disruption of ALLEvaluate carefully for stabilityLOOK FOR CENTRAL CORD SYNDROME27Types of Injuries28Flexion Teardrop Fracture C5-6fracture is the result of a
18、 combinationof flexion and compression,most commonly at C5-6The teardrop fragment comes from the anteroinferior aspect of the vertebral body.The larger posterior part of the vertebral body is displaced backward into the spinal canal.Best seen on lateral viewIt is an completely unstable fracture asso
19、ciated with complete disruption of ligaments and anterior cord syndrome and quadriplegia 70%of patients have neurologic mon in MOTOR VECHICLE ACCIDENT 29Signs:Prevertebral swelling associated with anterior longitudinal ligament tear.Teardrop fragment from anterior vertebral body avulsion fracture.Po
20、sterior vertebral body subluxation into the spinal canal.Spinal cord compression from vertebral body displacement.Fracture of the spinous process.30Fracture of the body Fracture of the body of c5 with a small of c5 with a small fragment fragment anteriorlyFracture of the spinous process of C4Acute a
21、ngulation at the level of Acute angulation at the level of C5C6 with displacement of C5 in C5C6 with displacement of C5 in posterior directionposterior direction3132333435Wedge fracture Compression fracture resulting from flexion.Flexion compression injury Best seen on lateral viewStableCommon in El
22、derly patients with osteoporosis or osteogenesis imperfecta3637Wedge shape vertebraAntersuperior body fracture38Hangmans Fracture C-2Fx through the pars interarticularis of C2 secondary to hyperextensionBest seen on lateral viewHyperextention injury Stable fracture?394041 The most common scenario wo
23、uld be frontal motor vehicle(hitting dash board)Hanging falls,diving injuriescontact sports.Neurological involvement is rare 4243Classification of Hangman s fractures Type I(65%)hair-line fractureC2-3 disc normalType II(28%)displaced C2disrupted C2-3 discligamentous rupture with instabilityC3 antero
24、superior compression fractureType III(7%)displaced C2C2-3 Bilateral interfacet dislocationSevere instability44TYPE 1 HANGMAN FRACTURE There is a hair-line fracture and there is no displacement.C23 NORMAL 45HANGMAN FRACTURE TYPE 3 Anterior dislocation of the C2 vertebral bodyBILATRAL C2 pars BILATRAL
25、 C2 pars interarticularis interarticularis fractures.fractures.Prevertebral soft Prevertebral soft tissue swelling tissue swelling 46The CT-images confirm the fracture-lines of the hangmans fracture.They run through the pars interarticularis resulting in a traumatic spondylolysis.In this case there
26、was no neurologic deficit,because the spinal canal is widened at the level of the fracture.4748Extention tear drop fracture AVULSION FRACTURE of anterio inferior content of the axis resulting from hyperextentionThis injury is stable in flexion but highly unstable in mon in diving accidents It also m
27、ay be associated with the central cord syndrome.495051The CT confirms the displaced anteroinferior bony fragment.This fragment is a true avulsion,in contrast to the flexion teardrop fracture in which the fragment is produced by compression of the anterior vertebral aspect due to hyperflexion.52Jeffe
28、rson Fracture C-1 Best seen on odontoid view Unstable fracture Fracture due to AXIAL LOADING frequently associated with diving into shallow water(axial blow to the vertex of the head)impact against the roof of a vehicle fall from playground equipments Fracture is caused by a a compressive compressiv
29、e downward forcedownward force that is transmitted evenly through the occipital condyles to the superior articular surfaces of the lateral masses of C1.This process displaces the masses laterally and causes fractures of the anterior and posterior arches,along with possible disruption of the transver
30、se ligament.53SIGNS ON XRAY:Displacement of the lateral masses of vertebrae C1 beyond the margins of the body of vertebra C2.2mm bilateral is always abnormalC6T1Best seen on lateral viewPowerful Hyperflexion injury(shoveling)Stable fracture Common in motor vehicle accidentssudden muscle contractiond
31、irect blows to the spine 6869Ap view show ghost sign with 2 spinous processes?70Case 15 yo girlHit by car while riding bikeVSA at sceneVitals recovered by EMSRose et al,Am J Surg 2003;185(4)71Atlanto-Occipital Dislocation2.5 x more common in children than adultsDue to small occipital condyles and ho
32、rizontal atlanto-occipital jointsSuspect if distance between occipital condyles and C1 is 5mm at any pointUsually have+soft tissue swelling72OccipitoAtlantal Dissociation (OAD)Commonly FatalPresent 6-20%of post mortem studies Alker et al,1978 Bucholz&Burkhead,1979 Adams et al,199250%missed injury ra
33、te1/3 Neurological Worsening Davis et al,199373OccipitoAtlantal Dissociation (OAD)Symptoms/Findings Wallenberg SyndromeLower Cranial nerve deficitsHorners syndromeCerebellar ataxiaCruciate paralysisContralateral loss of pain and temperature74Radiographic LinesRadiographic LinesBC/OA1 considered abnormalLimited UsefulnessPositive only in Anterior Translational injuriesFalse Negative with pure distractionPowers et al,Neurosurg,1979 Powers Ratio75QUESTIONS76REFERRENCESText Book of Radiology and imaging(DAVID SUTTON)Primer of Diagnostic ImagingRadiology Review Manual(Dahnert)77
