胸腰椎骨質(zhì)疏松骨折處理

Approximately2millionpeoplesustainanosteoporoticfractureintheUnitedStateseachyear;25%ofthosearevertebralcompressionfractures.Mostfracturescanbetreatednonoperatively,usingacombinationofbracing,physicaltherapy,andpainmedications.Surgicaltreatmentmaybeconsideredforpatientswithseverepainorwhohavefailednonoperativeoptions.Surgicaltreatmentoptionsincludevertebroplastyandkyphoplasty,whichinvolvetheinjectionofbonecement(polymethylmethacrylate)toaugmentvertebralbonestrength;kyphoplastyaddsthein?ationofaballoontamptohelpreducethefractureandcreateaspaceforthecement.Theriskofcementextravasationisrelativelyhigh,especiallyduringvertebroplasty;however,theincidenceofsymptomaticleaksisrelativelylow.Overall,bothproceduresofferlowcomplicationrates,excellentpainrelief,andimprovedfunctionaftervertebralcompressionfractures.SeminSpineSurg22:58-66?2010ElsevierInc.Allrightsreserved.KEYWORDSvertebralcompressionfracture,osteoporosis,vertebroplasty,kyphoplasty,man-Agement在美國，每年大約有200萬人發(fā)生骨質(zhì)疏松骨折，其中25％是椎體壓縮性骨折。大多數(shù)骨折可以采用支具、理療、止痛藥等聯(lián)合的非手術(shù)治療，對于嚴重疼痛或非手術(shù)治療失敗者可以采用手術(shù)治療。手術(shù)治療包括后凸成形和椎體成形術(shù)，通過注入骨水泥（聚甲基丙烯酸甲酯）增強椎體。后凸成形通過球囊擴張來復位骨折，并為骨水泥制造一個空間。骨水泥滲漏的機會比較高，特別是椎體成形術(shù)。但產(chǎn)生癥狀者較少?？傮w而言，兩種手術(shù)的并發(fā)癥都很低，都能顯著緩解疼痛，提高椎體壓縮性骨折的功能。關(guān)鍵詞：椎體壓縮性骨折，骨質(zhì)疏松，椎體成形術(shù)，后凸成形術(shù)，治療。第一頁，共33頁。SpectrumofDiseaseSenileorinsuf?ciencyfracturesareprimarilytheresultofosteopeniaandosteoporosis,de?nedbytheWorldHealthOrganizationasatscorelessthan1andlessthan2.5,respectively.1Thetscoreisthenumberofstandarddevia-tionsbetweenthepatient’sbonemineraldensity(BMD)andthatofthereferencevalueoftheBMDofayoungadult.Itisbelievedthatosteoporosisdevelopsbecauseoftheuncou-plingofthenormalbalancebetweenboneresorptionandnewboneformation,2resultinginanetdecreaseinbonemass.Osteoporosiscanbeprimary,secondary,oridiopathic.Primaryosteoporosis,themostcommonform,canbedividedinto2subgroups,senileandpostmenopausal.Senileosteopo-rosisisaslow,graduallossofbonemass,andisconsideredanormalpartoftheagingprocess.PostmenopausalosteoporosisisarapiddecreaseinBMDseenafterawomanentersmeno-pause.Secondaryosteoporosiscanberelatedtoasystemicdisease,suchasdiabetes,ortomedications,suchascorticosteroidsorantiseizuremedications.Idiopathicosteoporosis,asthenameimplies,hasnoidenti?ablecause.疾病概況世界衛(wèi)生組織定義當t值小于﹣1～﹣2.5時，為骨質(zhì)疏松，其首發(fā)癥狀常是骨折。t值是患者的骨密度（BMP與年輕成年人骨密度參考值的標準差。骨質(zhì)疏松是由于骨吸收與骨形成之間失衡，從而引起骨量減少。骨質(zhì)疏松分為原發(fā)性、繼發(fā)性和特發(fā)性。原發(fā)性骨質(zhì)疏松是最常見的類型，可再分為老年性和絕經(jīng)后。老年性骨質(zhì)疏松骨量丟失逐漸發(fā)生，進展較慢，為老年的正常改變。絕經(jīng)后骨質(zhì)疏松在停經(jīng)后骨密度迅速下降。繼發(fā)性骨質(zhì)疏松多源于系統(tǒng)性疾?。ㄈ缣悄虿。┗蛩幬铮ㄈ缙べ|(zhì)激素或抗癲癇藥物）。特發(fā)性骨質(zhì)疏松正如其名所示，沒有明確的原因。第二頁，共33頁。TheNationalOsteoporosisFoundationestimatesthatthereare8millionwomenand2millionmenwithosteoporosisintheUnitedStates.3Another34millionpeoplearebelievedtohaveosteopenia.3Itisestimatedthatone-halfofwomenandone-quarterofmenagedmorethan50yearswillsustainanosteoporosis-relatedfractureintheirlifetime,4whichtranslatesintoapproximately2millionfracturesperyearintheUnitedStates,includingapproximately300,000hipfracturesand550,000vertebralcompressionfractures(VCF).4VCFscurrentlyleadtoanestimated$17billionindirectmedicalcosts,whichmayincreaseto$25.3billionby20254and$50billionby2040.5Thesefracturesalsoresultinmorethan400,000hospitaladmissionsannually.3國際骨質(zhì)疏松基金會估計，美國有800萬婦女和200萬男性患有骨質(zhì)疏松癥，另有3400萬人骨量減少。大約一半的婦女和四分之一的男性在年齡超過50歲后會發(fā)生骨質(zhì)疏松性骨折，其中大約200萬發(fā)生骨折，包括30萬的髖部骨折和55萬的椎體壓縮骨折（VCF）。VCF目前的直接醫(yī)療消費大約為170億美元，到了2025年增加到253億美元，2040年將達到500億美元。每年因這些骨折而住院的人數(shù)超過40萬。第三頁，共33頁。Approximately2millionpeoplesustainanosteoporoticfractureintheUnitedStateseachyear;25%ofthoseareVCFs,whichcanbesymptomaticorasymptomatic.AsymptomaticVCFsmaybeidenti?edincidentallyonimagingstudiesorbytheincreasingkyphoticpostureofthepatient.Approximatelyone-third(23%-33%)ofpatientswithVCFspresentwithacutepain.6BothsymptomaticandoccultofVCFsmayoccurspontaneouslyormaybetheresultoflow-energytrauma,suchasafall.SomeofthemorecommonriskfactorsforVCFincludefemalegender,increasedage,smoking,andfrequentfalls(Table1).7-10Inmen,alowtestoster-onelevelisasubstantialriskfactor.美國每年骨質(zhì)疏松骨折的人數(shù)約為200萬，25％為VCF，其中有些有癥狀，有些沒有癥狀。無癥狀性骨質(zhì)疏松可因偶然拍片或進行性后凸發(fā)現(xiàn)。約有三分之一的VCF患者出現(xiàn)急性疼痛。無癥狀或癥狀性VCF均可由低能量損傷（如跌倒）引起。發(fā)生VCF的危險因素包括：女性，老齡，吸煙，頻繁跌倒等（表1）。對于男性，睪酮低下是重要的危險因素。第四頁，共33頁。VCFscanalsohaveaseriouseffectonapatient’soverallhealth.Eachfracturehasbeenestimatedtoresultina9%decreaseinforcedvitalcapacity11andhasalsobeenshowntodecreaseforcedexpiratoryvolume.12Inaddition,patientswhohavesustainedaVCFareata5timesgreaterriskfordevelopinganotherVCFthanistherestofthepopulation.13OfpatientswithVCFs,20%willhaveanadditionalVCFwithin1year13and50%willhaveanadditionalVCFwithin3years.14Thishighfractureriskmayberelatedtothein-creasedkyphosiscausedbytheanteriorwedgingoftheinitialVCFs.Withincreasedkyphosis,thebody’scenterofmassisshiftedanteriorly,whichinturnshiftstheloadcarriedbythespineanteriorlyandmayleadtoabnormalstresseswithinthevertebralbody,whichthenmayleadtonewfractures.PatientswithaVCFarealsoata2timesgreaterriskfordevelopinghipfractures.MortalityafterVCFhasbeenshowntobeashighas20%withinthe?rstyear.15,16Long-termmortalityrateshavebeenreportedas46.1%at3years,69.1%at5years,and89.5%at7years;roughlytwicethoseofagematchedcontrols.17VCF可對患者的總體健康狀況產(chǎn)生嚴重的影響。據(jù)估計，每骨折一次，存活率下降9％，同時也使患者的呼吸能力下降。此外，VCF的患者，再骨折的機會是沒有骨折者的5倍，其中20％在1年內(nèi)會再出現(xiàn)VCF，50％在3年內(nèi)會出現(xiàn)VCF。這種高骨折風險與初始VCF后椎體前側(cè)楔變從而引起進行性后凸有關(guān)。由于進行性后凸，身體的重心前移，從而使負荷由椎體前方傳導，在椎體上形成異常的壓力，從而形成新的骨折。VCF患者髖部骨折的發(fā)生率也將增加兩倍。VCF后第一年的死亡率達到20%。3年死亡率46.1%，5年死亡率69.1%，7年死亡率則達89.5%，大致為對照組的兩倍。第五頁，共33頁。DiagnosisandEvaluationVCFsshouldbesuspectedinat-riskindividualswithaxialbackpainorincreasingkyphoticposture.Rarely,patientsmayhaveradicular-orstenotic-typesymptoms.Evaluationbeginswithacompletemedicalhistory,withattentiontoanyhistoryofcancer,andathoroughphysicalexamination,includingassessmentoflowerextremityneurologicfunction.Theinitialimagingstudyisconventionalradiographs,whichwillfrequentlyshowthefracture;standingradiographsarenotusuallyrequired,buttheymaybeusefulinassessingthepatient’soverallkyphosisandsagittalbalance.Insomecases,computedtomographyimagingmaybeneededtovisualizefracturesthataresuspectedbutnotseenonpoor-qualityradiographsorfortheevaluationoffracturesintheupperthoracicspine,whichisknowntobedif?culttoevaluatewithconventionalradiographs.Computedtomographymayalsoassistinpreoperativeplanning,speci?callyintermsofevaluatingtheintegrityoftheposteriorwallofthevertebralbody.Magneticresonanceimaging(MRI)helpstodistinguishnew,acutefracturesfromolder,healedones.AcutefracturesshowincreasedsignalintensityonT2-weighted,fat-suppressedT2-weighted,andshorttauinversionrecoveryimages.IfthepatientisunabletoobtainanMRIstudy,abonescanmaybeused,buttheremaybealagtimebetweenfractureonsetandapositive?ndingonabonescan,leadingtoapossiblefalsenegativeresult.Theacuityofthefractureisanimportantdistinction:someauthorsbelievethathealedfracturesarelesslikelytorespondtovertebralaugmentationsurgery.18MRImayalsobehelpfulinevaluatinganycompressionoftheneuralelements,whetherfromretropulsionoftheposteriorwallorfromnarrowingoftheneuralforamen.Diffusion-weightedimagesmayhelptodistinguishpathologicfrombenigncompressionfractures.19Adual-energyx-rayabsorptiometryscanshouldbeperformedtoassessthepatient’sBMD.Medicaland/orcardiologyconsultsshouldbeobtainedasappropriateifsurgeryisplanned.Consultingapainmanagementspecialistmayalsobehelpful.診斷與評估背痛和進行性后凸應(yīng)懷疑椎體壓縮性骨折?；颊吆苌儆懈曰颡M窄癥狀。評估要從完整的病史開始，注意任何癌癥史，并做全面的體格檢查，包括下肢神經(jīng)功能。常規(guī)X線片通?？梢燥@示骨折，站立位不是必須的，但有助于評估患者的整體后凸情況及矢狀面平衡。對某些X線不清楚而懷疑骨折或普通X線難以辨認的上胸椎患者，CT有助于看清骨折。CT也有助于術(shù)前評估，特別是椎體后壁的完整性。MRI有助于區(qū)別新鮮骨折還是陳舊骨折。急性骨折在T2加權(quán)、T2加權(quán)壓脂相、短梯度翻轉(zhuǎn)還原相上表現(xiàn)為高信號。如果不能做MRI，也可以做一個骨掃描，但由于骨折發(fā)生與骨掃描陽性之間有一個時間遲滯現(xiàn)象，可能出現(xiàn)錯誤的陰性結(jié)果。鑒別出新鮮的骨折十分重要，因為治愈的骨折對椎體增強無反應(yīng)。MRI也有助于神經(jīng)受壓情況，如椎體后壁骨折塊移位或椎間孔狹窄。彌散加權(quán)像有助于區(qū)別是不是病理性骨折。還必須做一個雙能X線吸收掃描來評估一下患者的骨密度。如果計劃手術(shù)，要請內(nèi)科或心血管科會診，疼痛專家會診也是很有用的。第六頁，共33頁。TreatmentNonoperativeInitialtreatmentofVCFsisnonoperative:acombinationofpainmedication,physicaltherapy,andpossiblybracing.Painmedicationsshouldbemultimodalandmayincludecombinationsofnarcotics,nonsteroidalanti-in?amatorymedications,antidepressants,andneuropathicagents.Eachoftheseclassesofmedicationshassubstantialside-effectpro-?les,includingsedationfromnarcoticsandgastrointestinalandcardiaceffectsfromnonsteroidalanti-in?amatorymedications,whichareaccentuatedinelderlypatients.Apainmanagementspecialistandthepatient’sprimarycarephysicianshouldbeinvolvedintheprescribingofanyofthesemedications.治療非手術(shù)治療VCF的首選治療是非手術(shù)治療，止痛藥、理療、支具相結(jié)合。止痛藥有多種機制，包括麻醉藥、非甾體抗炎藥、抗抑郁藥、神經(jīng)營養(yǎng)藥等。每種藥都有一定的副作用，包括麻醉藥的鎮(zhèn)靜作用、非甾體抗炎藥的胃腸道反應(yīng)和心血管反應(yīng)，尤其是老年人。疼痛專家和患者的初級治療師也要參與其中。第七頁，共33頁。Physicaltherapyhasbeenshowntoimproveapatient’spainandtoreducetheriskoffuturefractures.20,21Initially,therapyshouldfocusoncorestrengtheningtoimprovepostureandspinalmechanics.22Focusingonstrengtheningthebackextensorsmayhelptodecreaseloadsonthespine.21Proprioceptivetrainingmayhelpreducetheriskoffallandpreventfurtherinjury.23理療可以減輕疼痛，并減少再發(fā)骨折的危險。最初的治療著重改進姿勢和脊柱力學。強化背伸肌有助于減少脊柱上的負荷。本體覺的訓練有助于減少跌倒，防止更多的損傷。第八頁，共33頁。Theuseofabracemayhelptoimmobilizeandsupportthespine,decreasingthepainassociatedwiththefracture.Bracesmayalsohelptoimproveposture,decreasingsomeoftheloadonthespine.Multiplebracingoptionsareavailable,includingJewettandcruciformanteriorspinalhyperextensionbraces,thoracolumbosacralorthoses,andposture-trainingsupportorthoses.Patientcompliancewithbracingmaybedif?cultbecausethebracescanbeuncomfortableandhardtoputonandtakeoff.Inaddition,patientswhoareoverweightorwhohaveaseveredeformitymaybedif?cultto?twithbraces.支具有助于制動，支持脊柱，減少骨折引起的疼痛。支具也有助于改善姿勢，減少脊柱上的負荷。目前有多種支具可選，包括Jewett支具、十字形過伸支具、胸腰骶支具、姿勢訓練支具等?；颊呖赡懿辉概宕髦Ь?，因為支具可能不舒服，穿脫也很困難。另外，體重過大或嚴重畸形者，也很難使用支具。第九頁，共33頁。Selectivenerverootinjectionsorspinalepiduralinjectionsmaybehelpfulforpatientswithfracturesthatcompresstheneuralelements.Epiduralinjectionsmaybeparticularlyusefulforpatientswitharetropulsedfragmentinvadingthespinalcanalbutwhoarenotgoodsurgicalcandidates.Selectivenerverootinjectionsmaybeusedforpatientswithradiculartypesymptoms.選擇性神經(jīng)阻滯或硬膜外阻滯對骨折伴有神經(jīng)受壓者是有用的。硬膜外阻滯對椎管占位但又沒有手術(shù)指征者特別有用，選擇性神經(jīng)根阻滯對有神經(jīng)根癥狀者有效。第十頁，共33頁。Inadditiontotreatingthefracture,theclinicianshouldaddressthepatient’sosteoporosisorosteopenia.Thistreatmentshouldbeorchestratedinamultidisciplinaryfashion,involvingthesurgeon,thepatient’sprimarycarephysician,andpotentiallyanendocrinologist.Asmentionedpreviously,adual-energyx-rayabsorptiometryscanshouldbeobtainedtomeasurethepatient’sBMD.Thepatient’snutritionshouldbemaximized,ensuringsuf?cientintakeofvitaminD(800-1000IU/d)24andcalcium(1200mg/d).25Medicalmanagementmayincludetheuseofbisphosphonates,calcitonin,estrogen,raloxifene(aselectiveestrogenanalog),andparathyroidhormone.Currently,theAmericanBoardofObstetricsandGynecologyrecommendsprescribingoneofthesemedicationsforanypatientsustaininganosteoporoticfracture,awomanwithatscoreoflessthan2,orapatientwithatscoreoflessthan1withatleast1associatedriskfactor.26Recently,alarge,multicenter,prospectiverandomizedcontrolstudyevaluatedtheuseofzoledronicacid(anintravenouslyadministeredbisphosphonate)afterosteoporotichipfracturesandfounda35%reductionofriskfornewfractureanda28%reductioninmortalityat1.9years.27Thoseauthorsnotedrelativelyminorcomplicationswiththemedication,includingmyalgia,pyrexia,andmusculoskeletalpain.Therewerenoepisodesofjawnecrosis,andtheratesofrenalandcardiaceventswereinboththetreatmentandplacebogroups.治療骨折，臨床醫(yī)師要確定有無骨質(zhì)疏松或骨質(zhì)減少。治療必須多學科綜合配合，包括外科醫(yī)師、患者的初級治療師、也可能要內(nèi)分泌醫(yī)師。正如前文所提的，要做雙能X線吸收掃描，以測定患者的BMD.患者的營養(yǎng)要充分，保證每天攝入800－1000IU的維生素D和1200mg的鈣。內(nèi)科治療包括雙膦酸鹽、鈣、雌激素、雷洛昔芬（一種選擇性雌激素類似物），甲狀旁腺素等。最近，美國婦產(chǎn)科委員會提出，一旦有骨質(zhì)疏松骨折或T值小于–2的婦女，或T值小于–1同時至少有一個危險因素者應(yīng)開始服藥治療。最近一項大型、多中心、前瞻性隨機對照研究發(fā)現(xiàn)，唑來膦酸（一種靜脈用雙膦酸鹽）用于骨質(zhì)疏松髖部骨折，可以降低35％的再骨折發(fā)生率，在1.9年可降低28％的死亡率。這些作者提到了少量的并發(fā)癥，包括肌痛，發(fā)熱、骨骼肌肉疼痛等。沒有出現(xiàn)下頜壞死這種少見情況。治療組與安慰劑對照組的腎臟與心臟并發(fā)癥均有發(fā)生。第十一頁，共33頁。OperativeGiventhatmostVCFsoccurinelderlypatientswithoutneurologicde?citswhohavemedicalcomorbiditiesandosteopeniaorosteoporosis,conventionalsurgicaltechniques,suchasinstrumentedfusion,havebeenavoidedforthetreatmentofVCFs.However,withtheadventofpercutaneousvertebralaugmentation,suchpatientshavebecomecandidatesforsurgicalintervention.Thereare2basicformsofpercutaneousvertebralaugmentation,vertebroplastyandkyphoplasty.Bothproceduresaresimilarinpositionandapproach,buttheyhavetechnicaldifferences.Vertebroplastywasintroduced?rstinFrancein1984andwasdescribedin1987byGalibertetal.28ItwasnotintroducedintheUnitedStatesuntil1994.29Vertebroplastyinvolvestheinjectionofcement,usuallypolymethylmethacrylate(PMMA),intothefracturesite.Recently,kyphoplastyhasbeenintroduced.Thisprocedureinvolvesthein?ationofaballoon-typebonetampbeforetheinjectionofthePMMA,whichmayallowforthepartialreductionofthefractureandthecreationofavoidintowhichthecementcanbeinsertedunderlowpressure.手術(shù)治療由于大多數(shù)VCF沒有神經(jīng)損害，同時有內(nèi)科并存病和骨質(zhì)疏松，傳統(tǒng)的外科手術(shù)如器械固定融合并不合適。隨著經(jīng)皮椎體增強技術(shù)的出現(xiàn)，這類病人可以進行外科干預。經(jīng)皮椎體增強技術(shù)有兩種方式：椎體成形術(shù)和后凸成形術(shù)。兩種手術(shù)的體位和入路相同，但有技術(shù)上的不同。椎體成形術(shù)1984年在法國開始應(yīng)用，1987年Galibert等首先報道。在美國，直到1994年后才開始應(yīng)用。椎體成形術(shù)是將骨水泥（通常是聚甲基丙烯酸甲酯，PMMA）注入骨折部位。近來，后凸成形術(shù)開始應(yīng)用，后凸成形術(shù)是通過一個球囊進行擴張，使骨折部分復位，并制造一個空腔，這樣就可以在比較低的壓力下注入骨水泥。第十二頁，共33頁。IndicationsforSurgeryTheindicationsforvertebroplastyandkyphoplastyinthetreatmentofVCFsincludeacute,painful,osteporoticorosteolyticVCFs;pathologicfracturesinpatientswithmetastaticdisease;painfulvertebralhemangioma;andKummell’sdisease.30,31Itisimportantthatonlysymptomaticfracturesbetreatedandnotallfracturesthatareseenonimagingstudies.31Mostcommonly,VCFsaretreatedacutely,althoughchronicfracturesmayalsorespondtotreatment.ThebestmethodfordifferentiatingacuteorsubacuteVCFsfromchronicfracturesisviatheuseofMRIand,speci?cally,fatsuppressedT2-weightedorshorttauinversionrecoverysequenceimages.Fracturesthatshowincreasedsignalintensity(compatiblewithedema)onthesepulsesequencesarelikelytobeacuteorsubacuteandhaveahighchanceofrespondingfavorablytovertebralaugmentationproceduresintermsofpainrelief.手術(shù)適應(yīng)癥椎體成形術(shù)和后凸成形術(shù)的手術(shù)適應(yīng)癥包括：急性、疼痛性骨質(zhì)疏松性椎體壓縮骨折；轉(zhuǎn)移癌引起的病理性骨折；痛性椎體血管瘤；Kummell氏病。只有有癥狀的骨折才需要治療，而不是所有影像所見的骨折都需要治療。雖然慢性骨折對治療也有效，但VCF大多在急性期治療。區(qū)別急性或亞急性骨折與陳舊性骨折的最好方法是MRI，特別是壓脂T2加權(quán)或短T翻轉(zhuǎn)恢復序列，在這些序列上信號增高的（可能有血腫），可能是急性或亞急性骨折，椎體增強的止痛效果較好。第十三頁，共33頁。Contraindicationsforvertebralaugmentationincludede?ciencyoftheposteriorwall,localorsystemicinfection(sepsis),osteoblasticmetastaticlesions,inabilitytoobtainadequateintraoperativeimaging,andadvancedormultiplemedicalcomorbidities.Inaddition,performingtheseproceduresonfractureswithseverecollapseandvertebraplanamaybetechnicallychallenging.椎體增強的禁忌癥包括：后壁不完整，局部或全身感染，成骨性轉(zhuǎn)移灶，術(shù)中無法提供影像支持，伴有多發(fā)或嚴重的內(nèi)科并存病。此外，在嚴重塌陷和扁平椎實施該手術(shù)也是一項技術(shù)挑戰(zhàn)。第十四頁，共33頁。SurgicalTechniquePatientpositioningforvertebroplastyandkyphoplastyissimilar.Patientsareusuallypositionedproneonaradiolucenttable.Aswithallpronepatients,careshouldbetakentoprotecttheeyesandtopadallbonyprominences.Inrarecases,patientsmaybepositionedinthelateralposition.Ideally,thebackshouldbeextendedtofacilitatereduction.Anesthesiamaybegeneral,sedation,orlocal,dependingonthecircumstanceandthepatient’smedicalcondition.外科技術(shù)椎體成形術(shù)和后凸成形術(shù)的體位相似?；颊咄ǔ８┡P于可透視床上，由于是俯臥位，要注意保護眼睛，并在骨突上置墊。少數(shù)情況下，也可以置于側(cè)臥位。背部過伸，以利復位。麻醉可用全麻、鎮(zhèn)靜或局部麻醉，取決于具體情況和患者條件。第十五頁，共33頁。Afterthepatienthasbeenpositionedonthetable,initial?uoroscopicimagesshouldbeobtainedintheanteroposterior(AP)andlateralplanes.TheimagesintheAPviewshouldbeadjustedintokyphosisorlordosisasneededuntilatrueAPviewofthevertebralbodyinquestionisobtained.Whenproperlypositioned,bothvertebralendplatesshouldbeclearlyvisualized,andthepediclesshouldbesymmetricandequidistantfromthespinousprocess.Adequate?uoroscopicimagingisessential,andthesurgeryshouldnotproceediftheimagesarenotsatisfactory.Oneor2?uoroscopyunitscanbeused,dependingonmachineavailabilityandsurgeonprefer-ence.Theuseof2?uoroscopyunitshasbeenshowntodecreaseoperatingroomtimeanddecreasetheincidenceofcementextravasation.32病人擺好體位后，先做個正側(cè)位透視，前后位要調(diào)整適應(yīng)病椎的前凸或后凸，以獲得真正的前后位。如果位置正確，椎體上下終板顯示清晰，雙側(cè)椎弓根對稱，與棘突的距離相等。良好的影像十分重要，如果圖像不滿意就不應(yīng)進行手術(shù)。用一臺還是兩臺透視機取決于條件和外科醫(yī)生的喜好。兩臺透視機有助于減少手術(shù)時間和減少骨水泥滲漏的機會。第十六頁，共33頁。Afterthepatientissuccessfullypositioned,thevertebratobeaugmentedislocalized.Theanteriorvertebralbodycanbeapproachedviaatranspedicular,extrapedicular,orposterolateralapproach.Thechoiceofapproachshouldbeidenti?edpreoperatively,basedontheimagingstudiesandlocationofthefracture.ThetranspedicularapproachistypicallyusedforvertebraebetweenT10andL5.Thisapproachmaybedisadvantageousforpatientswithsmallpediclesorforthosewhosevertebraearecollapsedbelowthelevelofthepedicle.Theextrapedicularapproachisusuallyusedforhigherthoraciclevelsorvertebraewithsmallpedicles.Ithastheadvantageofallowingmoremedialplacementoftheworkingcannula.Theposterolateralapproachisreservedforlumbarvertebraewithextensivecollapseorsmallpedicles,factorswhichwouldmakethestandardtranspedicularapproachtechnicallychallenging.在病人擺好體位后，要增強的椎體要定位好。可能通過經(jīng)椎弓根、椎弓根外、后外側(cè)入路到達椎體前側(cè)。入路的選擇要根據(jù)影像和骨折的部位，術(shù)前就確定好。經(jīng)椎弓根入路常用于T10－L5，對于椎弓根較小或椎體爆裂骨折位于椎弓根平面下者不合適。椎弓根外入路用于高位胸椎及椎弓根較小者，其優(yōu)點在于套管可以更偏向內(nèi)側(cè)放置。后外側(cè)入路用于腰椎嚴重爆裂或小椎弓根或采用標準經(jīng)椎弓根困難者。第十七頁，共33頁。Forthetranspedicularapproach,anincisionismadeapproximately2-3cmlateralfrommidline,inlinewiththempedicle.Theappropriatetrocarorneedleisselectedand,munder?uoroscopicguidance,itispositionedonthesuperolateralcornerofthepedicle.Thetrocarisadvancedusing?rmbutcontrolledpressure;frequentimagesareobtainedmtocon?rmlocation.Thetrocarshouldbeangledslightlymedial,butcareshouldbetakenthattheneedledoesnotcrossthemedialborderofthepedicleontheAPimageuntilithasreachedtheposterioraspectofthevertebralbodyandtheendofthepedicleonthelateralview.Ifthetrocarisnotedtocrossthemedialborderbeforethisstage,amedialbreachshouldbesuspected,andthetrocarshouldbewithdrawnandredirected.Afterthetrocarhasenteredthevertebralbody,itshouldcontinuetobeangledmediallyandshouldapproach,butnotcross,themidline.Anobliqueviewdirectedstraightdownthepediclemaybehelpfulforcon?rmingthepositionofthetrocarwithinthepedicle.Thisviewisobtainedbybringingthe?uoroscopyunitapproximately10°offthemidlinetoprovideaviewlinewiththepathofthepedicle.采用經(jīng)椎弓根入路，在中線外約2－3cm處椎弓根線做切口。選擇合適的套管針透視下置于椎弓根的外上角，穩(wěn)穩(wěn)控制前進，多透視以確定位置。套管針要輕度偏向內(nèi)側(cè)，但要注意，在側(cè)位上到達椎體后壁、椎弓根末端之前在前后位上不要超過椎弓根的內(nèi)側(cè)界。如果在此之間套管就超過了椎弓根的內(nèi)側(cè)界，要考慮內(nèi)側(cè)壁穿破，套管針要取出重新定向。一旦套管針進入椎體，要盡量向內(nèi)側(cè)傾斜，但不要超過中線。將球管偏離中線10°使球管方向與椎弓根方向一致的斜位片有助于確定套管針是否位于椎弓根內(nèi)。第十八頁，共33頁。Asmentionedpreviously,theextrapedicularapproachistypicallyusedinthemidtoupperthoracicspine.Atranspedicularapproachattheselevelsusuallyresultsinanunacceptablylateralplacementofthetrocar.Toperformtheextrapedicularapproach,thetrocarispositionedjustsuperiorandlateraltothepedicle,andmedialtotheheadoftherib.Occasionally,itisnecessarytocannulatethroughtheribhead.Thestartingpointshouldbeatoranteriortothelevelofthespinalcanalonalateralimage,whichminimizestheriskofspinalcanalviolation.Careshouldbetakennottoslideinferiororsuperiorofftheribhead,whereplungingwiththetrocarrisksinjuringthelung.如前所述，椎弓根外入路主要用于中至上胸椎，在這些部位，經(jīng)椎弓根入路套管針的側(cè)方位置無法接受。要采用椎弓根外入路，套管針必須位于椎弓根的外上方，并位于肋骨頭的內(nèi)側(cè)。偶爾，必須穿過肋骨頭。側(cè)位像上起點要位于椎管水平或其前方。小心不要向上或向下滑過肋骨頭，以免損傷肺臟。第十九頁，共33頁。Idealmedial-to-lateralpositioningwithinthevertebralbodymayvary,dependingontheuseofaunilateralorbilateralapproach(seediscussionlater).Additionally,idealsuperior-inferiorpositioningdependsonthenatureofthefracture.Thetrocarshouldbepositionedinproximitytothefracturedendplate,thatis,positionedadjacenttothesupe-riorendplateforsuperiorendplatefracturesandviceversaforinferiorfractures.Steensetal33suggestedthatendplate-to-endplatecementplacementoffersthebestbiomechanicalstrengthafteraugmentation.Thelocationofthecementwithinthevertebralbodyhasnotbeenshowntoaffectadjacentlevelfractures.34單側(cè)入路和雙側(cè)入路椎體內(nèi)的理想內(nèi)外位置不同（見后述討論）。理想的上下位置取決于骨折的性質(zhì)。套管的位置要接近骨折的終板，也就是說，上終板骨折要鄰近上終板，下終板骨折接近下終板。Steens等認為，終板骨水泥可便椎體強化獲得最好的生物力學強度。椎體內(nèi)骨水泥的位置不會造成鄰近節(jié)段骨折。第二十頁，共33頁。Oncethetrocarissuccessfullypositioned,thevertebralbodyshouldbebiopsiedbypassingaCraigorbiopsyneedlehroughtheworkingcannula.Althoughpatienthistory,physicalexamination,andimagingstudiesshouldsuggestwhetherthefractureisaresultofmalignancy,onlybiopsycancon?rmorrefutethispotentialcausativefactor.Schoeneldetal35reviewed80vertebralaugmentationprocedureson50patients,including8inpatientswhoweresuspectedofhavingVCFsbecauseofmalignancy.Theyreported4positivebiopsyresults,including3inpatientswhowerenotsuspectedofhavingamalignantprocess,leadingtoan8%rateofmalignancy.Additionally,7of8patientssuspectedofhavingamalignantracturewerefoundtohavebenignfractures.Biopsyresultscanhaveasubstantialimpactonpatientcare.套管針成功置入后，可以通過工作通道用Craig或活檢針做個活檢。盡管病史、體檢、影像都可以提示骨折是不是惡性腫瘤引起的，只有活檢是唯一可以確定或排除這種可能的方法。Schoenfeld等回顧了80例椎體增強手術(shù)中的50例患者，包括8例考慮為惡性腫瘤引起的VCF。4例活檢陽性，其中3例為沒有考慮為惡性，惡性率為8％。8例考慮為惡性者，7例發(fā)現(xiàn)為良性?；顧z的結(jié)果對患者的治療有重要的意義第二十一頁，共33頁。Oncethetrocarisinposition,thetechniquesusedforvertebroplastyandkyphoplastydiverge.Forvertebroplasty(Fig.1),thecementisinjecteddirectlyintothevertebralbodythroughthetrocar.Thecementisinjectedinalessviscousstateandunderrelativelyhighpressuretoallowpermeationthroughthecancellousboneofthevertebralbody.29Whenperformingkyphoplasty(Fig.2),anin?atableballoontampisinsertedthroughtheworkingcannulatoreducethefractureandtocreateacavityintowhichthecementwillbeinjected.Careistakentoensurethatnoadditionalendplatefracturesoccur.If2balloonsareused,theyshouldbein?atedalternatelytoensureevenexpansion.Afteradequatereductionisobtained,theballoonsarede?atedandwithdrawn,andthecementistheninjectedintothevoidsusingthetrocar.Usually,cement-?lledcannulasareplacedinthevoid,andtheirplungersareusedtoslowlypushoutthecement,althoughotherinsertiondevicesareavailable.Cementinjectionduringbothtechniquesshouldbecarefullymonitoredunder?uoroscopyandhaltedimmediatelyifthereareanyconcernsforextravasation.套管針放好后，椎體成形術(shù)與后凸形術(shù)的技術(shù)是不同的。椎體成形術(shù)（圖1）將骨水泥通過套管針直接注入椎體，骨水泥在低稠狀態(tài)下注入，注入的壓力相對較高，以使骨水泥滲入松質(zhì)骨中。后凸成形術(shù)（圖2）則通過工作通道置入一個可擴張球囊對骨折進行復位，并制造出一個空腔，以利于骨水泥注入。注意確定沒有另外的終板骨折發(fā)生。如果置入兩個球囊，要交替進行擴張，以使膨脹均勻。復位充分后，讓球囊萎陷，再取出。再注入骨水泥。通常將注滿骨水泥的套管放在空腔處，再用內(nèi)芯將骨水泥緩慢推出，也可能用別的器件。兩種技術(shù)都要在透視監(jiān)視下進行，一旦有骨水泥滲漏，立即停止。第二十二頁，共33頁。Whenperformingkyphoplasty,1or2balloonscanbeused.When2balloonsareselected,1isadvanceddowneachpedicleandshouldbepositionedfairlysymmetricallyinthevertebralbody.If1balloonisused,itshouldbepositionedasclosetomidlineaspossible,withcaretakennottocrosstoomediallyandviolatethespinalcanal.Using1balloonmaybeadvantageousforpatientswithsmallvertebralbodies,particularlyinthehigherthoraciclevels.The1-balloontechniquealsohastheadvantagesofshortenedoperatingroomtimeandlessradiationfrom?uoroscopybecauseonly1cannulaispassed.Chungetal36showedthatusing2balloonsresultedinincreasedfracturereductionandalowerincidenceoflossofreductionpostoperatively.However,theyfoundnodifferenceinpainreliefforthe2techniques.后凸成形術(shù)可以用一個或兩個球囊。如果用兩個球囊，兩側(cè)椎弓根各置一個，并要對稱放置。如果只用一個，則要盡可能靠中線放置。注意不要越過中線侵入椎管。用一個球囊對椎體較小者較為合適，如高位胸椎。用一個球囊也可以減少手術(shù)時間和減少透視，因為只要置入一個插管。Chung等發(fā)現(xiàn)用兩個球囊可以增加骨折復位，減少術(shù)后復位丟失的發(fā)生率。但他們也發(fā)現(xiàn)兩種技術(shù)在疼痛緩解上沒有區(qū)別。第二十三頁，共33頁。ClinicalResultsNumerousstudieshaveevaluatedtheclinicaleffectivenessofvertebroplastyandkyphoplastyforthetreatmentofosteopo-roticandosteolyticVCFs.Inarelativelylargestudy,Gar?netal37retrospectivelyreviewed1439patientswithVCFsandfoundthat90%hadsigni?cantpainreliefafterkyphoplasty.Inaddition,severalrecentmeta-analysesevaluatingthetreat-mentofVCFswithvertebroplastyandkyphoplastyhavebeenreported.Ecketal38reportedthatthepatients’painscoresontheVisualAnalogScale(VAS)decreasedby5.68(8.36-2.68)aftervertebroplastyandby4.60(8.06-3.46)afterkyphoplasty.TheseresultsaresimilartothosereportedbyHulmeetal,39whofounddecreasedVASscoresof5.2(8.2-3.0)aftervertebroplastyand4.8(7.2-3.4)afterkyphoplasty.Theslighttrendinbetterpainrelieffromvertebroplastywasnotseeninthemeta-analysisperformedbyGilletal,40whichfoundthatVASscoresdecreasedby5.44aftervertebroplastyand5.62afterkyphoplasty,orbythestudyperformedbyTayloretal,41whichlikewiseshowednosigni?cantdifference.Tayloretal41alsoshoweddecreasedpainscoreswithvertebralaugmentationat3,6,12,and36monthscomparedwithnonoperativetreatmentandthatthelengthofhospitalizationdecreasedfrom13.4to7.4days.Inaddition,multiplestudieshaveshownimprovedfunctional