Atlantooccipital Dislocation in Motor Vehicle Side

7/18/2019 Atlantooccipital Dislocation in Motor Vehicle Side

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Journal of CraniovertebralJunction and Spine

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Atul Goel

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Case Report

Atlantooccipital dislocation in motor vehicle sideimpact, derivation of the mechanism of injury, andimplications for early diagnosis

Kevin M. Smith, Narayan Yoganandan, Frank A. Pintar, Shekar N. Kurpad, Dennis J. Maiman

Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, USA

Corresponding author: Dr. Narayan Yoganandan, Department of Neurosurgery, Medical College of Wisconsin, 9200 West Wisconsin Ave., Milwaukee, WI 53226, USA.

E-mail: [email protected]

Journal of Craniovertebral Junction and Spine, 1:18

Abstract

Numerous reports of atlantooccipital dislocations (AODs) have been described in frontal impacts and vehicle

versus pedestrian collisions. Reports of survival after AOD in conjunction with side impacts have infrequently

been reported in the literature. The objective of this study is to present a case of an AOD from a side impact

vehicle collision, and deduce the mechanism of injury. A clinical and biomechanical reconstruction of the collision

was performed to investigate the mechanism of the dislocation. A 51-year-old female was traveling in a four-door

sedan and sustained a side impact collision with a compact pickup truck. At the time of extrication, the patient

was neurologically intact with a Glasgow Coma Scale score of 15. After admittance to the hospital, the patient

developed a decline in respiratory status, right mild hemiparesis, and left sixth-nerve palsy, and magnetic resonance

imaging (MRI) and computed tomography (CT) reconstructions indicated a craniocervical dislocation. Surgical

fixation was performed and all extra-axial hemorrhaging was evacuated. At discharge, the patient was neurologically

intact on the left side, had right mild hemiparesis, left sixth-nerve palsy, and minor dysarthria. Survival rates ofAODs have recently been increasing. Morbidity is still more prevalent, however. Due to the variety of symptoms

that accompany AODs and the inconsistency of diagnostic imaging techniques, a thorough history of the etiology

may lead to increased clinical suspicion of this injury and further raise survival rates.

Key words:Atlantooccipital dislocation, cervical spine injury, side impact collision

INTRODUCTION

Sysemaic diagnosis o alanooccipial dislocaion (AOD)has been described by Powers et al. based on X-rays.[1] Reporso adul AOD have been commonly described in ron-end

moor vehicle collisions wih unbeled occupans and airbagineracions.[2,3]o he knowledge o he auhors, only one rauma

paien has been repored in he lieraure who survived AODduring a side impac collision.[4]Repored AODs in he lierauresugges ha he presence o associaed injuries should lead oa high index o suspicion.[5] Cranial nerve deficis are commonamong such injuries.[1,6,7] We presen a rare case o a side impac

collision resuling in AOD wih relaed cranial nerve deficis.

CASE REPORT

PresentationTe paien was a 51-year-old emale, and was o 165 cm insaure and 101 kg in oal body mass. She was he driver o aour-door sedan sopped a a conrolled inersecion acingnorh. As he paien began a lef urn ino he wes bound lane,an eas bound hal-on pickup ruck enered he inersecion andcollided wih he driver side door o he case paiens vehicle.

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DOI:

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Journal of Craniovertebral Junction and Spine 2010, 1:18 Smith, et al.: AOD in motor vehicle side impact

Te paien was resrained in a hree-poin seabel and he rondriver-side airbag did no deploy.

Upon exricaion, he paien had a Glasgow Coma Scale (GCS)score o 15, and she was immobilized in a hard cervical collarand ranspored o a local hospial. From here, she was airlifedo our Adul Level One rauma Cener, wih a sabilized GCSscore o 15. weny-our hours afer admission, he paien

developed mild dysarhria and bradypnea. Afer decline inrespiraory saus, he paien was inubaed and immobilized ina halo brace. Diagnosic radiograph, magneic resonance imaging(MRI), and hree-dimensional compued omography (3D C)images were obained. Te paien also developed a lef cranialnerve VI palsy and quadriparesis a his ime.

Radiographic examinationPlain X-ray radiographs indicaed an anerior AOD wih aPowers Raio 1.1 [Figure 1][1]. Te AOD was confirmed wihC scans [Figure 2], and imaging o he brain revealed asubarachnoid hemorrhage in he poserior ossa. Inravenricularblood was noed in he ourh venricle and preponine ciserns.

MRI revealed a cervical cord conusion rom he occipu o C2,and an epidural hemaoma in he ecorial membrane and alarligamens a he C1C2 level [Figure 3]. Angiography findingsindicaed inimal ears o boh cervical verebral areries andrupure o he lef exernal caroid arery.

ManagementTe paien was aken o he operaing room, general aneshesiawas adminisered, and fiber-opic inubaion was perormed.Te paien was urned o he prone posiion wih he haloves in place. Te poserior porion o he ves was removedand occipiocervical alignmen was verified by inraoperaiveuoroscopy. Te occipu and upper cervical spine were exposed

hrough a sandard midline exposure. Te alas was compleelydislocaed rom he occipu, and disrupion o all alanooccipialligamens and capsule was seen. Rupure o he alar ligamens,

ecorial membrane, and inerior porion o he verical cruciaeligamen was also noed a C1C2 level. Te epidural hemaomawas evacuaed bilaerally rom around he spinal cord a heoccipuC2 level. C2C3 joins were inac. An occipuC2usion [Figure 4] was perormed using he Summi (Acromed/Johnson and Johnson, Raynham, MA, USA) sysem. Tisincluded placemen o hree screws ino he occipu, sublaminar

wires beneah he arches o he alas and across he lamina o C2bilaerally.

Postoperative courseTe paien was posiioned in a halo ves and moniored in heinensive care uni. Her quadriparesis parially resolved ino aresidual mild righ-side hemiparesis. Te sixh-nerve palsy onhe lef side did no improve. Significan diplopia was noediniially; however, his gradually resolved over he reamencourse. A he ime o discharge, he paien was neurologicallyinac on he lef side o her body. Te residual righ-sidehemiparesis persised, as well as he lef sixh-nerve palsy andminor dysarhria.

DISCUSSION

Reconstruction of the case collisionWhile survival afer AOD in a side impac collision has beenrepored, here is a lack o mechanisic undersanding o hemechanism o injury.[4,8] Te presen sudy adds o he bodyo lieraure and emphasizes he occurrence o AOD caused byvehicle-size mismach. Invesigaion o he collision deerminedha he inerior o he sedan door and pars o he ruck grillesruck he lef side o he occupan during impac. Te lefshoulder and rib cage o he paien were orced ransversely

oward he midline and downward. During he ime o vehicle-o-vehicle conac, he ruck hood and upper regions o hegrille were above he driver side window sill. Using an exemplar

Figure 1: Lateral radiograph of the cervical spine and illustration

of the Powers Ratio demonstrating an anterior dislocation of the

atlantooccipital joint

Figure 2: Lateral CT reconstruction showing atlantooccipital

dislocations. Note the abnormal width of the atlantooccipital joint

and the misalignment of the articulating surfaces


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Figure 3: MRI of the spinal cord contusion and epidural hematoma

are shown

Figure 5: The schematic illustrating the mechanism of the

atlantooccipital dislocations in side impact

Figure 4: Postoperative image showing the surgical procedure

Table 1: Associated injuries separated into body region and organs

Injuries Head and neck Thorax/

abdomen

Osseous/ligamentous Subluxation of C1 and

C2; complete rupture

of the atlantooccipital

capsule; complete

rupture of tectorial

membrane and inferior

portion of vertical

cruciate ligament;

complete rupture

of alar, anterior

longitudinal, posterior

longitudinal, and

transverse ligaments

Fractures of

left posterior

15 and right

anterior 12 ribs

Vascular Left conjunctival

hemorrhage; left

facial laceration (6

cm); contusions

to left side of the

neck; subarachnoid

hemorrhage within

posterior fossa;

intraventricular blood

in fourth ventricle and

prepontine cisterns; left

external carotid artery

tear; bilateral intimal

tears of the cervical

vertebral arteries;

epidural hematoma

at C1C2, anterior

and bilateral to thespinal cord; epidural

hematoma to tectorial

membrane and alar

ligaments

Left lung

contusion; left

side hemothorax;

grade 1 liver

laceration

Neurological Left sixth-cranial

nerve palsy with

resultant diplopia; mild

dysarthria; cervical

cord contusion with

quadriparesis

Residual right

mild hemiparesis

occupan and vehicle, i was verified ha he impacing ruckshood ron edge was a he level o he paiens craniocervicaljuncion. Furher analysis based on her anhropomery indicaedha he level o her skull base and mandible was mainainedagains he ruck hood as he lef shoulder and rib cage wereracured and coninuously orced ransversely and downward.Te impac produced a disracive orce along he lengh o he

spine and induced ensile orces o he ligamens o he uppercervical spine, resuling in AOD [Figure 5].

Clinical evidence for the injury mechanismSeveral repors describe various injuries in combinaionwih AOD. Few specific sympoms have been observed.[7,9- 11] Diagnosis is usually based on associaed injuries and


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a high degree o clinical suspicion.[4,7,10] A cervical spinedisracion mechanism resuling in AOD is ofen associaedwih acial abrasions and laceraions, mandible racures,arrhyhmia, apnea, asymmeric cranial nerve palsies, loss oconsciousness, subarachnoid hemorrhages, and horacic orabdominal injuries.[1,4,5,7,9-12] Our paien susained a numbero hese associaed injuries [able 1]. Limied rauma below

he abdomen included a grade 1 liver laceraion caused by heseabel. Furher, evidence o rauma was noed a he upper lefside o her horax, cervical spine, and cranial regions. Te iniialradiographs showing racures o he lef firs five ribs, wihhemohorax and concomian lef lung conusion were srongindicaions ha he maximum load o impac was a he upperhoracic region.

Embedded glass was ound in he lef acial laceraion. A lefconjuncival hemorrhage was noed in addiion o subsanialswelling and bruising on he lef side o he paiens ace, neck,and shoulder. Angiographic findings o he lef exernal caroidarery ears indicaed a subsanial amoun o orce, applied o

he cervical spine, during impac.As indicaed by MRI, complee rupure o he inerior vericalcruciae ligamen, alar ligamens, ecorial membrane, andhe enire alanooccipial ligamen complex urher localizedhe maximum load o impac o he high cervical spine. Aconsiderable amoun o orce is required o rupure he vericalcruciae ligamen and he ecorial membrane which suggesed asubluxaion a he C1C2 level.[13] Tis was a srong indicaionha majoriy o he orce was direced o he upper cervical spine.

Biomechanical sudies o cervical spine ligamen ensile srenghhave revealed ha he ligamens o he OCC1 juncion requirea high orce or complee rupure.[13,14]Tus, he resulan AOD

and rupure o he ligamen complex in his paien subsaniaedhe proposed disracion mechanism. Upon comparison, cervicalspine radiographs did no reveal any apparen differencesrom oher AODs caused by ronal impac. Tus, i can beconcluded ha he maximum load o impac was ocused a healanooccipial juncion o our paien.

Analysis of brainstem and cranial nerve deficits

in atlantooccipital dislocationsAsymmeric moor deficis are ofen caused by direc spinalcord injury or compression o he brainsem hrough damageo he surrounding bony or vascular srucures.[6] Delayed

onse, wih rapid progression, o neurologic defici indicaesha sympoms are due o compression and no direc injury.Based on he ime o onse o specific neurological deficis inour paien, diagnosic angiography was used o invesigae hesurrounding vasculaure. Inimal ears o boh verebral areries(consequen o dissecion) provided one plausible explanaionor he dysarhria, bradypnea, and quadriparesis ha occurredin a delayed ashion.[15-18] Compression o cranial nerve X inhe same region was associaed wih he bradypnea.[16-18] Tecranial nerve VI palsy was no immediaely explained by heangiographic findings.

Analysis o he cervical MR scans revealing he anerior andbilaeral epidural hemaoma and he spinal cord conusionprovides he basis or quadriparesis and a urher explanaion orhe decline in respiraory saus. Compression and sreching ohe spinal cord was noably inuenced by displacemen o heoccipial condyles rom he alas, which resuled in he spinalcord conusion. Te epidural hemaoma ound in he ecorial

and alar ligamens along wih he rupured alanooccipialligamen complex and capsule probably allowed swelling inhe region o urher compress he brain sem and cranialnerves.[9,11,12,19]

Damage o verebral and caroid areries, and vascularsrucures wihin he ligamen complexes probably resuled inhe subarachnoid hemorrhage in he poserior ossa, and heinravenricular blood in he ourh venricle and preponineciserns.[12,19] I is likely ha blood in hese regions creaedpressure on he nucleus o he sixh-cranial nerve, and henuclei o he hypoglossal and vagus nerves.[19,20] Te resulanabducens nerve palsy and dysarhria may be explained by heseobservaions.

Addiional suppor or our hypohesis is provided by he relaedsympoms o occipial condyle racures. In hese injuries,ColleSicard syndrome is commonly ound which includesdefici o cranial nerves IXXII, and in AOD, some variaion ohe ColleSicard syndrome can be expeced.[20] Consequenly,i he dislocaion is no recognized early, damage caused byAOD could resul in compression o he lower cranial nervesand brain sem wih delayed onse o neurological deficis. [1,7,12]

We sugges immediae careul radiological evaluaion o healanooccipial juncion whenever lower cranial nerve deficisare observed in he conex o a side impac collision. We also

sugges ha even when paiens are neurologically inac a hescene, a side impac collision o his naure probably merisa careul consideraion o cervical sabilizaion and urgenradiological evaluaion or poenial AOD. Te suggesedmechanism o injury should assis in he biomechanicalundersanding o hese injuries. Examinaion o he disribuionpatern o associaed injuries as noed in his case is an addiionalreliable way o indicae AOD in rauma paiens.

ACKNOWLEDGMENTS

Tis sudy was suppored in par by he Unied SaesDeparmen o ranspor aion Naional Highway raffi c

Saey Adminisraion DHN22-10-H-00292, and DNH22-05-H-41001, and he Deparmen o Veerans Affairs MedicalResearch. Te assisance o Mr. Dale Halloway is graeullyacknowledged. Te maerial presened in his manuscriprepresens he posiion o he auhors and no necessarily hao he NHSA.

REFERENCES

1. Powers B, Miller MD, Kramer RS, Martinez S, Gehweiler JA Jr. Traumatic

anterior atlanto-occipital dislocation. Neurosurgery 1979;4:12-7.



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117

2. Mokri B, Silbert PL, Schievink WI, Piepgras DG. Cranial nerve palsy in

spontaneous dissection of the extracranial internal carotid artery. Neurology

1996;46:356-9.

3. Yoganandan N, Haffner M, Maiman DJ. Epidemiology and injury biomechanics

of motor vehicle related trauma to the human spine. SAE Trans

1990;98:1790- 807.

4. Seibert PS, Stridh-Igo P, Whitmore TA, Dufty BM, Zimmerman CG. Cranio-

cervical stabilization of traumatic atlanto-occipital dislocation with minimal

resultant neurological deficit. Acta Neurochir (Wien) 2005;147:435-42.

5. Payer M, Sottas CC. Traumatic atlanto-occipital dislocation: presentation ofa new posterior occipitoatlantoaxial fixation technique in an adult survivor:

technical case report. Neurosurgery 2005;56:203.

6. Ahuja A, Glasauer FE, Alker GJ Jr, Klein DM. Radiology in survivors of traumatic

atlanto-occipital dislocation. Surg Neurol 1994;41:112-8.

7. Bel labarba C, Mirza SK, West GA, Mann FA, Dailey AT, Newell DW, et

al. Diagnosis and treatment of craniocervical dislocation in a series of

17 consecutive survivors during an 8-year period. J Neurosurg Spine

2006;4:429-40.

8. Yoganandan N, Pintar FA, Maiman DJ, Cusick JF, Sances A Jr, Walsh PR. Human

head-neck biomechanics under axial tension. Med Eng Phys 1996;18:289-94.

9. Adams VI. Neck injuries: II. Atlantoaxial dislocation--a pathologic study of 14

traffic fatalities. J Forensic Sci 1992;37:565-73.

10. Anderson AJ, Towns GM, Chiverton N. Traumatic occipitocervical disruption:

a new technique for stabilisation. Case report and literature review. J Bone

Joint Surg Br 2006;88:1464-8.

11. Horn EM, Feiz-Erfan I, Lekovic GP, Dickman CA, Sonntag VK, Theodore

N. Survivors of occipitoatlantal dislocation injuries: imaging and clinical

correlates. J Neurosurg Spine 2007;6:113-20.

12. Przybylsk i GJ, Clyde BL, Fitz CR. Craniocervical junction subarachnoid

hemorrhage associated with atlanto-occipital dislocation. Spine (Phila Pa

1976) 1996;21:1761-8.

13. Myklebust JB, Pintar F, Yoganandan N, Cusick JF, Maiman D, Myers TJ, et al.

Tensile strength of spinal ligaments. Spine (Phila Pa 1976) 1988;13:526-31.

14. Yoganandan N, Pintar FA, Larson SJ. Frontiers in Head and Neck Trauma:

Clinical and Biomechanical. The Netherlands: IOS Press; 1998. p. 743.

15. Ahn JY, Chung YS, Chung SS, Yoon PH. Traumatic dissection of the internal

maxillary artery associated with isolated glossopharyngeal nerve palsy: casereport. Neurosurgery 2004;55:710.

16. Kim T, Chung S, Lanzino G. Carotid artery-hypoglossal nerve relationships in

the neck: an anatomical work. Neurol Res 2009;31:895-9.

17. Machnowska M, Moien-Afshari F, Voll C, Wiebe S. Partial anterior cervical

cord infarction following vertebral artery dissection. Can J Neurol Sci

2008;35:674-7.

18. Maiman DJ, Yoganandan N. Biomechanics of cervical spine trauma. Clin

Neurosurg 1991;37:543-70.

19. Garton HJ, Gebarski SS, Ahmad O, Trobe JD. Clival epidural hematoma

in traumatic sixth cranial nerve palsies combined with cervical injuries. J

Neuroophthalmol 2010;30:18-25.

20. Kato MY, Tanaka I. Toyoda. Delayed lower cranial nerve palsy (Collet-Sicard

syndrome) after head injury. Injury 2006;37:104-8.

Source of Support:Nil, Conflict of Interest:None declared.


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Atlantooccipital Dislocation in Motor Vehicle Side