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A76-year-oldwomanpresentedwithbilateralkneepain,leftworsethanright.Pre-operativeradiographsoftheleftkneeshowsevere,end-stageosteoarthritis.Theradiographichallmarksofosteoarthritisare:jointspacenarrowing,sclerosisofthesubchondralbone,osteophyteformationandeventuallycysticchangesintheadjacentboneStandingalignmentviewsareusedtodeterminethepatient'sweightbearingandmechanicalaxis.ThetechnicalgoalsofTotalKneeArthroplastyincludere-establishingthepatientsmechanicalaxisandrestoringthejointline.Oftentimes,patientswillhavedevelopedseverevarusdeformity(bowedlegs)orlesscommonly,valgusdeformity(knockkneed).Afterasterileprep,thelimbisdraped,landmarksareidentifiedandthemid-linekneeincisionisplannedunlesspatientshaveoldscarswhicharenotcompatiblewiththisstandardincisionThelegisexsanguinatedandatourniquetisusedtomaintainhemostasisthroughoutthecase.Oncetheincisionismade,thequadricepstendon,thepatellaandthepatellartendonareidentified.Amedialpara-patellararthrotomyismadeandthesofttissuesareelevatedfromthetibia.Greatcaremustbetakennottostriptomuchmediallyorlaterallyasthismayresultindisruptionofthemedialcollateralligamentorthepatellartendon,respectfully.Botharedisastrouscomplications.Thepatellaandpatellartendonarereleasedfromtheunderlyingfatpadandothersofttissuessothepatellamaybeevertedlaterallytoexposethedistalfemurandproximaltibia.Afterthepatellaandtendonareeverted(underrakeinphoto),remainingcapsulartissuesarereleased.Thepatellar-femoralligamentabovetheclampisabouttobedivided.Onlyasinglecutismadetopreparethetibia.Anextramedullaryalignmentguideisplacedandsecuredwithpinsintheproximaltibia.ThisguideisusedtoresecttheproperamountofboneandcreatethepropersurfaceangulationforthenewtibialjointlineSeveralpinsareplacedtosecuretheguide.Oncetheguideissecure,thearthriticarticulatingsurfaceofthetibiaisresectedusinganoscillatingsawAfterthecutismadewiththeoscillatingsaw,thesectionoftibiaisremoved.TheresectedarthriticarticularsurfaceofproximaltibiaisshownAfterthetibialboneisresected,edgesandanyremainingboneareremoved.Unlikethetibia,anintra-medullaryguideisusedtomaketheresectioncutsonthefemur.Aholeisreamedfromdistaltoproximalinthefemursotheguidemaybeplaced.ThefemoralguideholeisshownTheplacementoftheintra-medullaryguidewithcuttingblockisshown.Oncethealignmentandrotationofthecuttingblockaredetermined,theblockissecuredintoplacewithpinsIncontrasttothetibia,aseriesofcutsaremadetopreparethedistalaspectofthefemur.Thefirstandmostimportantisthedistalfemoralcut.ThiswillbeusedtodeterminesofttissuebalancingandproperpositioningofthereplacementcomponentsOsteophytesareresectedafterthedistalcutiscompleted.Thekneeisthenextendedandaspacerblockispositionedtochecktheaccuracyoftheproximaltibiaanddistalfemoralcuts.Thesecutsultimatelydeterminethepositionofthekneereplacementcomponents,theadequacyofthesofttissuebalancingandtheoverallsuccessofthearthroplasty.AtensioningdeviceisusedtodetermineifadjustmentsarerequiredNext,aseriesofblocksareusedtodeterminethepropersizeofimplanttobeselected.ThesizingblockispinnedtoassurepropersizeandpositioningThesizingblockisremoved.Thepinsareleftinplaceandareusedtopositionthecuttingblock.Theanterioraspectofthefemuristhenresected?nbsp...followedbytheposterioraspect?nbsp;...andfinallythechampfercuts(angledcutsconnectinganteriorandposteriorsurfaceswiththedistalsurface).SofttissueandexcessboneareremovedThediagramdemonstratestheplanesoftheanterior,posteriorandchampfercutsThenotchofthedistalfemurispreparedusingaseriesofguidesaswellTheanteriorpartofthenotchiscompletedwithaV-shapedcutThebottomnotchcutisshown.Onceallthecutsarecompletedthesurfacesarepreparedforplacementoftrialcomponents.Thetrialcomponentsareplacedtodetermineiffinaladjustmentsareneededandoccasionallytodetermineifalargerorsmallersizedcomponentshouldbeused.Here,thefemoraltrialisplaced.ThefemoraltrialcomponentisshowninplaceOncethefemoraltrialcomponentispositionedtheposteriorcapsuleofthekneeisreleasedandosteophytesareremovedThefemoralcomponentisthenremovedtogainaccesstothetibialsurface.AsizingguideisusedtodeterminethefitforthetibialcomponentThetibialguideispinnedintoplaceThetibialguidehasanextensionthroughwhichanalignmentrodisplaced.ThisisyetanotherbuiltinwaytocontinuallyreassessthepositioningofthefinalimplantsAcavityiscreatedinthecancellousboneoftheproximaltibia.Theactualtibialimplanthasastemtoprovidegreaterstability.Then,bothfemoralandtibialcomponentsareplacedtogethertoassesshowtheyfunctioninunisonTheundersurfaceofthepatellaisalsoresected?nbsp;...measuredwithacaliper?nbsp...sizedappropriately?nbsp...andfittedwithatrialcomponent.AnyadjustmentsaremadeaftertakingthekneethroughaseriesofmotionandstabilitytestsThetrialcomponentsareremovedforafinaltimeAllpreparedsurfacesareinspectedforafinaltime.Therawbonesurfacesaretheirrigatedwithantibioticsolutionusingapulsatilelavagesystem.Thisremovesloosebonyfragmentsandparticles.Afterirrigating,thebonysurfacesaredriedandpolymethylmethacrylatebonecementisappliedtotheendofthefemur.Theactualfemoralstainlesssteelimplantisthenpositionedandimpactedforaperfectfi