骨坏死髓心减压术

CoreDecompressionforOsteonecrosisofthehipClinOrthop.2004;418:29-33DEVELOPMENTOFCOREDECOMPRESSIONOFTHEFEMORALHEADCoredecompressionofthehipisthemostcommonpro­cedurecurrentlyusedtotreattheearlystagesofONofthefemoralhead.FicatandArletthenhypothesizedthatONcouldbetreatedsuccessfullybydecompressingthefemoralhead.Thegoalofcoredecompressionwastodecompressthefemoralheadpressure,restorenormalvascularflows,andalleviatepaininthehip.Eventhoughnumerousstudieshavebeenpublishednogeneralconsensushasbeendevelopedregardingpatientselection,surgicaltechnique,classificationsystemsused,orpostoperativetreatmentofthesepatients.CLASSIFICATIONANDSTAGINGThepurposeofanyclassificationsystemistoprovideguidelinesfortreatmentandprognosis.Overtheyears,numerousdifferentclassificationssystemshavebeendevelopedtoevaluatepatientswithONofthefemoralheadbutcurrently,thereisnostandardunifiedclassificationsystemusedbyallinvestigators.ThereisgeneralagreementthattheprognosisforapatientwithONofthehipisinfluencedbytheextentandthelocationofthenecroticareainthefemoralheadandwhetherthereisinvolvementoftheacetabulum.FicatandArletoriginallydevelopedafour-stageclassificationsystembasedonradiographicchangesandthefunctionalexplorationofbonethatincludedintraosseousvenographyandmeasurementofbonemarrowpressure(Table1).NormalIScleroticorcysticlesionsIISubchondralcollapseIIIOsteoarthritiswithdecreasedarticularcollapseIVCriteriaStageTABLE1.RadiographicClassificationsofOsteonecrosisoftheFemoralHeadFicatandArletClassificationSystemSincethattime,numerousdifferentclassificationsystemshavebeendevelopedbuttheUniversityofPennsylvaniaSystemofClassificationandStaginghasthemostpotentialasausefulclinicalandresearchtool.BecauseitincludedMRIevaluations,whichallowforthequantificationoftheextentoffemoralheadinvolvement(Table2).AdvanceddegenerativechangesVIJointnarrowingand/oracetabularchangesVFlatteningoffemoralheadIVSubchondralcollapse(crescentsign)withoutflatteningIIILucentandscleroticchangesinfemoralheadIINormalradiograph;Abnormalbonescanand/orMRIINormalornondiagnosticradiograph,bonescan,andMRI0CriteriaStageTABLE2.UniversityofPennsylvaniaSystemofclassificationandStagingCOREDECOMPRESSIONTherehavebeennumerousextensiveliteraturereviewspublishedassessingtheclinicalresultsofcoredecompression.Smithetalreviewed12articlespublishedbetween1979and1991thatincluded702hipswithanaveragefollowupof38months.UsingtheUniversityofPennsylvaniaStagingSystem,successfulresultswerereportedasfollows:StageI,78%;StageII,62%;andStageIII,41%.Montandassociatesassessed42reportsinwhich1206hipsweretreatedbycoredecompressionand819hipsweretreatedbyvariousnonoperativemeans.nonoperativetreatmentwasnotsuccessful.Only23%ofhipsin21studieshadasatisfactoryclinicalresultwhentreatednonoperatively.In24studies,65%ofthehipstreatedwithcoredecompressionhadanoverallsatisfactoryclinicalresult.Furthermore,whenassessinghipstreatedbeforecollapse,goodresultswereobtainedin71%ofthehipstreatedwithcoredecompressionandin35%ofhipstreatednonoperatively.Stulbergetalcomparedcoredecompressionalonewithconservativetreat­mentinaprospectiverandomizedstudythatincluded55hips.Coredecompressionwassuccessfulin70%ofthehipsthatwereeitherFicatStageI,II,orIII.Incontrast,therewaslimitedsuccesswithnonoperativetreatment(FicatStageI,20%;FicatStageII,0%;FicatStageIII,10%).ItwasconcludedthatcoredecompressionwasmoreeffectivethannonoperativetreatmentforpatientswithearlystagesofON.Kooandassociatesdidarandomizedtrialon71hipsthatweretreatedbycoredecompressionornonoperatively.Radiographicprogressionwasseenin72%ofthehipstreatedwithcoredecompressionandin79%ofthehipsthatweretreatedsymptomatically.Seventy-twopercentofthehipstreatedwithacoredecompressioneventuallyrequiredaTHAand68%ofthehipstreatedsymptomaticallyrequiredaTHA.TheinvestigatorsconcludedthattherewasnosignificantadvantageintheoutcomewhenpatientswithONofthefemoralheadweretreatedwithcoredecompression.Smithandassociatesevaluated114hipsandshowedthattherewasasignificantdecreaseinsatisfactoryresultswhenacrescentsignwaspresent.ThesuccessrateinhipswithFicatStageIONwas81%butinhipswiththecrescentsignordefinitivecollapseofthefemoralheadthesuccessrateswere20%and0%Steinberganalyzed205patients(297hips)withaminimum2-yearfollowup.Thestageofthehip,accordingtotheUniversityofPennsylvaniaClassificationSystem,andthelesionsiteclearlyinfluencedthesuccessratesofcoredecompression.40%(StageII)39%(StageI)22%(StageI-II)requiredTHAheadinvolvement>15%headinvolvement<15%Aaronetal’evaluated118hipswithFicatStageIIorIllONwhichwastreatedwithcoredecompressionandcoredecompressionandhumanDBM.Survivalpercentisshowbelow:coredecompressionandhumanDBM(Group2)coredecompression(Group1)88%47%III83%72%IIFollowup-34monthsFollowup-40monthsStageTherealsohasbeenaninterestincombiningcoredecompressionofthefemoralheadwithbonegraftingorelectricalstimulationorbothtoenhancebonerepairinthefemoralhead.Steinbergetalfoundnoadvantagetosupplementingcoredecompressionwitheitherdirectcurrentorcapacita­tivecoupling.Bozicetalstudied54hipsthathadONofthefemoralheadwithameandurationoffollowupof120months(range,24-196months).Asuccessfulresultwasdefinedasoneinwhichthehipwasasymptomaticwithnoprogressionofthedisease.Anunsuccessfulresultwasdefinedasradiographicfailureorclinicalfailureorboth.Theauthorsshowedthatthesignificantpredic­torsofoverallfailureincludedanadvancedpreoperativeradiographicstage,ashortdurationofsymptoms,andtheuseofcorticosteroids.Noassociationwasseenbetweenage,gender,excessiveintakeofalcoholorrenaltransplantationandasuccessfuloutcome.SURGICALTECHNIQUEThereisgeneralagreementthattheprocedureshouldbedonewithfluoroscopicguidanceintwoplanes.Beforebegin-flingtheprocedure,theareaofONshouldbeidentifiedonAPandlateralradiographs.Itiscriticalthatthestartingholeforthecoredecompressionsitebemadejustabovethelevelofthelessertrochantertoreducetheriskofdevelopmentofastressfractureinthefemur.Fluoroscopicviewsaretakeninbothradiographicplanes.Progressivelylargerreamersareusedovertheguidewire(Fig.1).Reamingshouldstopatleast5mmfromthearticularsurfaceofthefemoralheaddependingonthepositionoftheguidewire.Aburrthenisusedtoremoveasmuchnecroticboneaspossible.Thecoretractthencanbegraftedwithautogenousboneobtainedfromthegreatertro­chanterandDBM.Thegoalistoprovideosteoprogenitorcellsandanosteoinductivematrixtoenhancebonerepairinthefemoralhead.Thesizeofonecoretractcanrangefrom9to12mmdependingonthediameterofthepatient’sfemur.Itispreferabletoobtainabiopsyspecimenfromthefemoralheadtoprovideadefinitiveconfinnationofthediagnosis.Protec­tiveweightbearingisrecommendedforaminimumof6weeksafterthesurgicalprocedure.Coredecompressionseemstobemoreeffectivethansymptomatictreatment.Tooptimizetheresultsofcoredecompression,theONmustbediagnosedandtreatedearly.Thesuccessofcoredecompressionisimprovedinprecollapsehipsinwhichthelesionissmallandthereisascleroticrimsurroundingthenecroticbone.ENDthanksbywbj