Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_6051_Библиотеки_им_академика_М_И_Перельмана
.pdf
If sufficientimaging can be performedand there is noidentifiablesite of compression,
closepatientobservationisadequate.
SteroidProtocol
Although its use is debated, methylprednisolone is currently the only recognized
pharmacologicinterventionforthetreatmentofacutespinalcordinjury(SCI).
13
Theuse
of steroids has not been extensively studied in the intra-operative setting; however, we
currentlyadministersteroidstopatientswhohaveacontinuednegativewake-uptest(i.e.,
absence of motor function) after release of tension from corrective and distractive
maneuvers.Thecurrentrecommendedprotocolisaloadingintravenousbolusdoseof30
mg/kgadministered over15 minutes,followedby5.4mg/kg/h asa 23-hourinfusion (if
startedwithin3hoursfromthe timeofinjury).
13
The useofmethylprednisoloneforthe
managementofintraoperativeSCIisnotwelldocumented.Thus,thesurgeonmustweigh
thepotentialbenefitsofimprovedneurologicrecoveryagainstthepossibleincreasedrisk
of infection. The American Association of Neurological Surgeons/Congress of
Neurological Surgeons (AANS/CNS) Joint Section on Disorders of the Spine and
PeripheralNervesGuidelinesCommitteehasindicatedthatmethylprednisoloneforeither
24 or48 hours is an optionin the treatment ofpatients with acute SCIsthat should be
undertakenonlywith theknowledgethat theevidencesuggestingharmful sideeffectsis
moreconsistentthananysuggestionofclinicalbenefit.
Intravenouslidocaine(2mg/kg)forvasodilatationhasbeendescribedfortreatmentofa
postulatedischemicspinalcordaftersegmentalvesselligation.
20
Inexperimentalanimal
models,intrathecalandintravenousvasodilatorshavebeenshowntoenhancespinalcord
perfusion and neuronal protection. However, we have no clinical experience with this
medicationandthuscannotcommentspecificallyonitsusefulness.
PostoperativeManagement
Apatientwithanintraoperativeneurologicinsultshouldbeadmittedtotheintensivecare
unit postoperatively for close monitoring of hemodynamic parameters as well as for
neurologicexaminations.MAPmustbemaintainedat>80mmHgwiththejudicioususe
of intravenousfluid replacement, blood transfusion(ifindicated), or vasopressors when
necessarytomaintaincordperfusion.Aβ-agonist(e.g.,dopamine)canbeusedtomaintain
mean arterial blood pressure if fluid replacement alone is insufficient. A neurologic
examinationshouldbeperformedanddocumentedeveryhourforthefirst12to24hours.
Thismay posea problemifthepatientremains intubatedand sedated.Inthiscase,it is
paramount that the patient be lightened from sedation on an hourly basis for effective
assessmentofneurologicfunction.
DelayedPostoperativeNeurologicComplications
Neurologiccomplications in thepostoperative periodshould bemanaged withthesame
diligenceandmeticulouscareasdescribedforanintraoperativeSCI.Althoughrelatively
uncommon, delayed postoperative SCI may be attributed to progressive spinal cord
ischemiasecondarytotractionortothedevelopmentofanepiduralhematoma.
As with any acute SCI, adequate perfusion of the spinal cord is paramount. Blood
pressureshouldbe meticulouslymonitored,andMAPshouldbe maintainedat>80 mm
Hg in an effort to sustain spinal cord perfusion. Vasopressors (e.g., dopamine) may be
requiredtoattainadequatebloodpressureandcord perfusion.Hemoglobinlevelsshould
alsobe checked toavoid excessivepostoperative anemia.Patient temperatureshould be
maintainedabove 36.5°C.Asteroid protocolmaybe initiatedasindicated aboveforthe
patientwithcontinuedneurologicloss.
Obtainingimagingstudiesbeforereturningthepatienttotheoperatingroommayaidin
delineatingthecauseofthedeficit.Thiswillenablethesurgeontoplanthepropercourse
ofaction,whetherthatinvolvesreexplorationforlocalizeddecompressionofanevolving
epiduralhematoma,releaseofcorrection,orremoval ofinstrumentationtocorrectspinal
cordischemiasecondarytoexcessivetensioning.ReimagingwithCTorMRIscanscanbe
omitted if obtaining these studies would result in a substantial time delay. Early
decompression may improve neurologic outcome for the patient with new-onset
neurologic deficit in the acute postoperative period. Conversely, if no abnormality is
identified on CT or MRI scan, the patient may be observed closely with supportive
treatment.
ChapterSummary
The surgical treatment ofcomplexadult spinal deformity has advanced significantly in
recenttimeswiththeuseofpediclescrew-basedinstrumentationandtheincreasingroleof
complex three-column osteotomies to optimize deformity correction. The correction of
large magnitude coronal and sagittal plane deformity is becoming more common.
However, the technical demands involved in restoration of spinopelvic alignment and
sagittal and coronal balance in large-magnitude deformities has a significant risk of
neurologiccomplications,withpotentiallydevastatingclinicalandfunctionalsequelae.It
isimportantthatspinalsurgeonsuseanalgorithmforthesafeandeffectivemanagement
ofneurologicsequelaeassociatedwithASDsurgerysoastooptimizepatientmanagement
andfunctionaloutcome.
Pearls
Neurologicsafetyduringspinaldeformitysurgeryrequirespreoperativepreparation,intraoperativemultimodality
spinalcordmonitoring,andpostoperativediligence.
AcombinationofSSEP,MEP,andEMGmonitoringisnecessaryforcomprehensiveassessmentandevaluation
ofneurologicfunctionduringASDsurgery.
AppropriateresponsestoanylossofdegradationofSCMdataandtowarningcriteriashouldincludeaspectrum
of responses aimed at optimizing spinal cord blood supply and minimizing any direct or indirect tension or
pressureontheneuralelements.
To confirm the patient’s neurologic integrity, one must always perform a detailed motor exam of the lower
extremitiesattheendofthesurgicalprocedurebeforethepatientisextubatedandleavestheoperatingroom.
Pitfalls
OnemustidentifythosepatientswhoareathighriskofneurologiccomplicationsduringASDsurgery,including
those with preexisting neurologic abnormalities, an abnormal neural axis on MRI exam, or large and stiff
kyphoticdeformities.
Notrespondingto or trustingtheSCMpersonnelanddataina timely fashioncanhavedevastatingneurologic
sequelae.
Onemustbecarefulwiththosepatientskeptintubated/sedatedfollowingextensiveASDsurgeryinordernotto
missadelayedneurologiccomplicationduetotheinabilitytoobtainanadequateneurologicexamonafrequent
basis.
References
FiveMust-ReadReferences
1. Dormans JP. Establishing a standard of care for neuromonitoring during spinal deformity surgery. Spine
2010;35:2180–2185PubMed
2. Malhotra NR, ShaffreyCI. Intraoperative electrophysiological monitoringin spine surgery.Spine2010; 35:2167–
2179PubMed
3.GelalisID,PaschosNK,PakosEE,etal.Accuracyofpediclescrewplacement:asystematicreviewofprospectivein
vivostudies comparing freehand,fluoroscopy guidance andnavigationtechniques. Eur SpineJ2012;21:247–255
PubMed
4.TianNF,Huang QS, ZhouP, etal.Pedicle screw insertion accuracywithdifferentassistedmethods: a systematic
reviewandmeta-analysisofcomparativestudies.EurSpineJ2011;20:846–859PubMed
5. Daubs MD, Lenke LG, Cheh G, Stobbs G, Bridwell KH. Adult spinal deformity surgery: complications and
outcomesinpatientsoverage60.Spine2007;32:2238–2244PubMed
6.Kim YB, LenkeLG,Kim YJ, et al.Themorbidity of ananteriorthoracolumbarapproach: adult spinaldeformity
patientswithgreaterthanfive-yearfollow-up.Spine2009;34:822–826PubMed
7.KimYJ,BridwellKH,LenkeLG, Cheh G, Baldus C. Results of lumbar pedicle subtractionosteotomies for fixed
sagittalimbalance:aminimum5-yearfollow-upstudy.Spine2007;32:2189–2197PubMed
8. Lapp MA, Bridwell KH, Lenke LG, et al. Long-term complications in adult spinal deformity patients having
combinedsurgeryacomparisonofprimarytorevisionpatients.Spine2001;26:973–983PubMed
9. Rhee JM, Bridwell KH, Lenke LG, et al. Staged posterior surgery for severe adult spinal deformity. Spine
2003;28:2116–2121PubMed
sagittalimbalance.JBoneJointSurgAm2003;85-A:454–463PubMed
10-yearassessment.Spine2007;32:2245–2252PubMed
followingcomplexadultspinaldeformitysurgery:theScoli-Risk-1trial.Spine2014submitted
2662PubMed
RelatRes1973;93:173–178PubMed
intraoperativesomatosensoryevokedpotentials.AnnNeurol1986;19:22–25PubMed
aortic clamping. The influenceof anesthetics andhypothermia.Ann Surg 1992;215:409–415,discussion415–416
PubMed
placement?Spine2002;27:2030–2035PubMed
mesylatefor48hoursinthetreatmentofacutespinalcordinjury.ResultsoftheThird NationalAcuteSpinalCord
InjuryRandomizedControlledTrial.NationalAcuteSpinalCordInjuryStudy.JAMA1997;277:1597–1604PubMed
surgery:apossibleroleforintravenouslidocaine.JPediatrOrthop1999;19:763–765PubMed
7
Postoperative Coronal Decompensation in
AdultDeformity
YongQiu
GeneralIntroductionofAdultScoliosis
Adultscoliosisisdefinedasanabnormaldeformityinanadult,withCobbangle greater
than 10 degrees in the coronal plane, with or without sagittal imbalance or abnormal
pelvic orientation.
1
In the elderly population, a variety of prevalence rates have been
reported asa result of differencesin definitions ofscoliosis, sample size,ethnicity,and
screeningtools. In astudy ofvolunteers who wereover 60years of age,Schwab etal
2
foundthat68%ofthesubjectsmetthedefinitionofscoliosis.AsreportedbyXuetal,
3
the
prevalenceofscoliosiswas13.3%inacohortof2395adultsolderthan40yearsofage.
Adultscoliosismaystemfromprogressionofscoliosisduringchildhoodoradolescence
(Fig.7.1), ormay benewly developedin adulthoodthrough degenerativechanges (Fig.
7.2). Theformer condition is referred toadult idiopathic scoliosis, whereasthe latter is
termeddegenerativescoliosisordenovoscoliosis.Incontrasttoadolescents,adultswith
scoliosis characteristically present with back pain, radiculopathy, and neurogenic
claudication. Cosmesis is a concern of some young adult scoliosis patients. They often
complainofwaistasymmetryandribsabuttingthepelvis,asaresultofimbalanceinthe
coronalplaneorthesagittalplane.
For adult scoliosis, nonoperative care is usually the first-line treatment option.
Nevertheless, surgerymay be inevitable when nonoperative measures fail. The primary
indications for surgery of adult scoliosis are (1) progressive deformity, (2) poor spinal
balance causing functional difficulties, (3) large deformity threatening cardiopulmonary
compromise, (4) neurologic manifestations, (5) persistent pain that fails to respond to
nonoperativetreatment, and (6)unacceptable cosmeticappearance.
1,4–6
Bess etal,
7
ina
multicenterreviewof290patients withadultscoliosis,reportedthatoperativetreatment
forolderpatientswasprimarilydrivenbypainanddisability,independentofradiographic
measurements,and,foryoungerpatients,byincreasedcoronalplanedeformity.Although
operative management of adult scoliosis is a growing challenge, a variety of surgical
optionshasbeenemployed,includeposterior,anterior,orcombinedapproaches.Silvaand
Lenke
6
proposedsixdistinctlevelsofsurgicaloptionsforadultdegenerativescoliosis:I,
decompressionalone;II,decompressionandlimitedinstrumentedposteriorspinalfusion;
III,decompressionandlumbarcurveinstrumentedfusion;IV,decompressionwithanterior
andposteriorspinalinstrumentedfusion;V,thoracicinstrumentationandfusionextension;
andVI,inclusionofosteotomiesforspecificdeformities.
Fusionlevelsshouldstartproximallyatastablevertebra,typicallyaboveT6orbelow
T10,andenddistallyataneutralandstablevertebra.Theproximallevelneverstartsatthe
thoracic kyphosis apex, avoidingproximaljunctional kyphosis, whereas the distal level
neverendsatalevelwithrotatorysubluxation.ThedecisionofwhethertoincludeL5or
the sacrum in the fusion is controversial.
8,9
Fusion distally to L5 offers the theoretical
benefits of preserved lumbosacral motion, shorter surgical time, and a decreased
likelihood of pseudarthrosis; on the other hand, it carries the potential for accelerated
symptomaticadvanceddegenerationattheL5/S1disk,whichinturnultimatelyresultsin
axial discomfort, radiculopathy, and loss of lumbosacral lordosis. In contrast to L5,
fusions extendedto the sacrum achievea higher stabilityof fixation as wellas a better
correction of sagittal imbalance, but this procedure also runs the risk of an increasing
chanceofpseudarthrosis,agreaterfrequencyofmajorcomplications,andahigherrateof
instrumentationfailure.
8,9
Arecentstudyalsofoundfusiontothesacrumtobeoneofthe
riskfactorsofproximaljunctionalkyphosis.
10
Non-controversialindicationsforfusionto
the sacrum include the following
6
: (1) an oblique take-off of L5 on the sacrum, (2) a
lumbosacralfractionalcurve>15degrees,(3)advanceddegenerationoftheL5/S1diskor
theL5/S1facetjoints,(4)L5/S1spondylolisthesis,and(5)priorhistoryofdecompression
atthissegment.Whenfusiontothesacrumcannotbeavoided,itisimportanttoperform
aninterbodyfusionbetweenL5andS1todecreasetheriskofanonunion.
Fig.7.1a–e(a,b)A57-year-oldwomanwithahistoryofadolescentidiopathicscoliosis.(c–e)Bothcoronalandglobal
sagittalbalancewaswellmaintained,andtheL2/3diskheightwasmuchbetterpreservedontheconvexsidethanonthe
concaveside.
DifferentiatingBetweenDegenerativeandIdiopathic
Scoliosis
Anessentialpremiseofthetreatmentofspinaldeformityinparticularisunderstandingits
etiology.Aebi
1
developedin2005aclassificationforadultscoliosisbasedontheetiology:
type 1, de novo scoliosis; type 2, progressive idiopathic scoliosis; type 3a, secondary
degenerativescoliosis, duetoa preexistingcondition,eitherintrinsic(adjacentcurve)or
extrinsic(lowerlimblengthdiscrepancy)tothespine;andtype3b,scoliosissecondaryto
metabolic bone disease. However, it is difficult to differentiate the clinical etiology in
elderlypatients whoareunable toprovide eitheramedical historyor informationabout
theirspinal deformity.As thereisa paucityof informationin theliterature, thischapter
describes several experience-based radiographic criteria that may help to differentiate
betweendenovoandidiopathicscoliosis.
Fig.7.2a–dAdultdegenerativescoliosisina65-year-oldwoman.(a)StandingX-rayfilmsshowedaright-sidedlumbar
curve,rotatorysubluxationat L3/4, and regional kyphosisfrom L3toL5aswellassagittal imbalance. (b)Magnetic
resonance imaging of advanced disk degeneration showed dark disks with narrowed disk height. (c,d) Computed
tomographyscansdemonstratedthevacuumphenomenonaswellascanalstenosisinthelowerlumbarregion.
ApicalDiskHeight
Inde novoscoliosis, asymmetricaldisk degenerationhasbeen regardedas theinitiating
factor that contributes to the occurrence of degenerative scoliosis. Asymmetric
degenerationintheapicaldisksleadstoasymmetricdiskcollapse,inducingacurvatureby
pivoting on the apical facet joint at the concave side, which in turn exacerbates more
degenerationofthe disksontheconcave sidethanontheconvexsideandthenstart the
vicious circle. Bao et al
11
also found that regional lumbar disk degeneration correlated
withthecoronalCobbangle,confirmingthatasymmetricdiskdegenerationcontributedto
the development of de novo scoliosis. We observed that the convex disk height was
significantlylessindenovoscoliosis(Fig.7.2)thaninidiopathicscoliosis(Fig.7.1).
CurvePattern
Themajorityofdegenerativescoliosisaffectsthelumbarorthoracolumbarspine,andtheir
curve patterns may be different from that of idiopathic scoliosis. Because the original
pathogenesisofdenovoscoliosisisthedegenerationofdiskandfacetjoints,theapexof
thelumbarcurveisoftenlocatedattheintervertebralspace.Themostcommonapexofde
novoscoliosisistheintervertebralspaceofL2/3orL3/4,oftenwithashortercurvespan.
Inaddition,thelevelsinvolvedinthedegenerativecurvearegenerallythreetofourlevels,
whereasfourtosixlevelsaremorecommoninidiopathiccurves.
RegularityofApicalVertebra
Inadditiontocurvepatterns,the apicalvertebrain denovoscoliosisisoftenirregularly
wedged.Osteophytes,end-plateabruption,andosteoporoticminorfracturearecommonly
seenindegenerativevertebrae,sotheshapeofvertebramaynotberegularlytrapezoid.In
contrast, wedging of apical vertebra, if any, is usually regular in idiopathic lumbar
scoliosis.
CompensatoryCurveAbovetheMainCurve
Regular compensatory curves proximal to the main curve in idiopathic scoliosis may
develop during adolescence, and serve as a way to re-balance the distal
thoracolumbar/lumbar curve in the coronal plane (Fig. 7.1). That explains why global
coronal imbalance is less frequent in adolescent idiopathic scoliosis cases with double
curve patterns, owingtothe compensatory curve and its compensatory abilityfrom the
diskal,pelvic,andcertainlyspinalmuscularstructureaswell.Thisbalancingpatternmay
continue into adulthood and last for a long time. This feature of compensatory curves
couldserveasanimportantradiographicsigntodifferentiatethesetwoentities.
Patientswith de novoscoliosis oftenpresent earlywith coronalor sagittalimbalance
due to the less effective compensative curves above the imbalance. In contrast with
sagittal imbalance, there is paucity of information in the literature on the incidence of
coronalimbalanceindenovoscoliosis.Basedonourstudy,
11
aboutonethirdofpatients
withdenovoscoliosismaypresentwithcoronalimbalanceduetoalackofcompensatory
curves.Similarto thefunctionalscoliosisseeninyoungindividualswithdisk herniation
or otherlower back diseases,trunk shifting isnot uncommon inde novo scoliosiswith
stenosis because of the pain-alleviating mechanism. This trunk shifting or coronal
imbalancewithspinalcurvemaybecomestructuralwithtime.
CorrelationBetweentheCobbAngleandImbalance
The discrepancy between the Cobb angle and imbalance in de novo scoliosis is an
interestingfinding.Degenerativecurvesalwaysareshorterthantheidiopathiccurvesand
have a smaller Cobb angle. As mentioned earlier, coronal imbalance is an important
featureof de novoscoliosis, whateverthe Cobbangle, whereassignificant imbalanceis
mostlywitnessedinadultidiopathicscoliosiswithseverecurves.Therefore,asmallCobb
anglewithobviouscoronalimbalanceindicatesthatthecurvemightbedegenerative(Fig.
7.2).
CorrectionAbilityofRotatorySubluxation
Vertebral rotatorysubluxation (VRS)isatriaxialdeformity,predominantlyat theL3/L4
level,withfemale predominance.Althoughit ismorelikely tooccurinpatients withde
novoscoliosisattheearlystageofthedeformity,itcouldalsooccurduringthelatecourse
ofadultidiopathicscoliosis.Atourcenter,wefoundthatthecorrectabilityofVRSunder
traction or on side-bending films could be used to differentiate de novo scoliosis and
idiopathic scoliosis. In the former, reduction of VRS under tractionor on side bending
maynotbeachievedbecauseoftherigidityfromvertebraldegenerationatthesubluxation
level,including diskcollapse, osteophytes,and spontaneousvertebralor facetfusion. In
contrast,inidiopathicscoliosis,VRScouldbepartiallyreducedundertractionoronside
bending.
DiscrepancyBetweentheCobbAngleandRotatory
Subluxation
AtourcenterwenotedthatVRSwasmoreliketooccurwhentheCobbangleincreasedin
casesof idiopathicscoliosis.However,inde novoscoliosis,VRSmayoccur atitsearly
stage,anditsonsetandseveritymaynotnecessarilybecorrelatedwiththeCobbangle.In
otherwords,VRSindenovoscoliosismaydevelopevenincaseswithasmallcurve.
TheOriginofStenosis
Accordingtothedefinitionofdenovoscoliosis,itsprimarycauseisthedegenerationof
spine,includingdisks,themuscle–ligamentscomplex,andthefacetjoint.Lumbarstenosis
ismorecommonlyseeninprimarydegenerativescoliosisthaninadultidiopathiccurves.
Therefore, radicular leg pain and claudication should be more common in de novo
scoliosis,evenwithsmallcurves.Thisisinaccordancewithourclinicalobservationthat
mechanicalback pain isthe mostcommoncomplaint inmany adultidiopathicscoliosis
patients due to deformity-induced paraspinal muscle fatigue, whereas neurogenic back
pain in combination with leg pain is the most common complaint in de novo scoliosis
patients(Fig.7.2).
Соседние файлы в папке Библиотека им академика М.И. Перельмана