proximal humerus fractures in the...

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Abstract

Proximal humerus fractures in the elderly are a relatively rare injury, the treatment of which remains controversial, especially regarding Neer displaced two-part, and three-part and four-part fractures. Operative indications for most displaced proximal humerus fractures in the elderly remain poorly defined, but recent literature is actually supporting less aggressive approaches except for the most severe frac-tures. Recent epidemiological and larger scale retrospec-tive studies fail to show a significant functional difference between operative and non-operative treatment of displaced two-part and three-part fractures in the elderly. Most four-part fractures appear to be best treated with hemiarthro-plasty. Recent meta-analyses show a need for well-executed, randomized, prospective studies that can be used to provide evidence-based templates for appropriate management of displaced proximal humerus fractures in the elderly.

Proximalhumerusfracturesintheelderlyarearela-tively rare injury, and appropriate treatment, espe-ciallyofdisplacedfractures,remainscontroversial.

Theincidenceofproximalhumerusfracturesis4%to5%ofallfractures.1Thereisaunimodaldistribution,withthisfractureoccurringinpeopleover70yearsofage.However,unlikemanyosteoporoticfractures,proximalhumerusfrac-turestendtooccurinthefitelderly.Eighty-sevenpercentoftheseinjuriesareduetogroundlevelfallsandarenearlythreetimesmorecommoninwomenthanmen.2,3Minimallyornondisplacedfracturescomprise85%oftheseinjuries,2,3

andnon-operative treatment isgenerally the treatmentofchoice.4There isnoconsensus in the literatureregardingtheoptimumtreatmentoftheremaining15%ofproximalhumerusfractures.Therearemanytreatmentoptions,rang-ing from closed treatment5-7 to prosthetic replacement,3yettheindicationsforoperativemanagementandthebestsurgicaloptionsarenotwell-delineated.Inaddition,recentmeta-analysesandlargerretrospectiveandprospectiveserieshavenotshownaclearadvantagetooperativeversusnon-operativemanagementformanytypesofproximalhumerusfractures,includingmanydisplacedfractures.5-10

AnatomyThekeytoclassifyingandtreatingproximalhumerusfrac-turesisunderstandingproximalhumerusanatomy.Neer3describedfourwell-definedpartsoftheproximalhumerus:thegreatertuberosity,thelessertuberosity,theproximalshaft, and the humeral head.The Neer classification ofproximalhumerusfracturesisbasedondisplacementandangulationof thesefourparts.Thesignificanceof theseparts lies in thedeformingforces thatacton themoncetheyarefractured.Theseforcesactasfollows:1.therota-torcuffcausesproximalandposteriordisplacementofthegreater tuberosityandmedialdisplacementofthelessertuberosity and humeral head through the subscapularis;2.thepectoralismajorcausesmedialdisplacementofthehumeralshaft;and3.thedeltoidcausesabductionofthehumeralshaft(Fig.1).4

Although thevascular supplydoesnotplaya role inNeer’sclassificationscheme,itisimportanttounderstand,asitmayhelpdictateappropriatemanagementbyhelpingtopredictthepost-fracturevascularityofthehumeralhead.Therearethreemaincontributionstothevascularsupplyofthehumeralhead.Thearcuateartery,aninterosseousvesselthatistheterminalbranchoftheanteriorhumeralcircumflex,isthemainarterialcontributiontothehumeral

Proximal Humerus Fractures in the ElderlyAre We Operating on Too Many?

Toni M. McLaurin, M.D.

ToniM.McLaurin,M.D.,isanAssistantProfessorofOrthopaedicSurgery in the NYU-HJD Department of Orthopaedic Surgery,NewYork,NewYork.Correspondence: ToniM.McLaurin,M.D.,NYUMedicalCen-ter,DepartmentofOrthopaedicSurgery,550FirstAvenue,NBV21W37,NewYork,NewYork10016.

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headandperfusestheentireepiphysis.Damagetothisves-selrequiresamoredistalanastomosistocompensateforthelackofbloodsupply.Abranchoftheposteriorhumeralcircumflexsuppliesasmallportionoftheposteroinferiorpart of the articular surface, and small vessels enteringthroughtherotatorcuffinsertionsalsosupplyinconsistentvascularitytothehumeralhead(Fig.2).Bothofthesesup-plyvascularity toamuchlesserdegree thanthearcuateartery.4

ClassificationAstheNeerclassificationisbasedonthesefouranatomicalparts, it is important toobtainadequateandappropriateradiographstodeterminethepresenceoffracturelines,dis-placement,andangulation.Thestandardshoulder“traumaseries”consistsofanAPoftheshoulder,ascapularYview,and an axillary view (Fig. 3).Additional studies, suchasinternalandexternalrotationviewsandtransthoraciclateralviews,canaddmoreinformationwhentheclassi-ficationisequivocal.AccordingtotheNeerclassification,displacementgreaterthanonecentimeterorangulationofmorethan45°isrequiredforclassificationasapart.Al-thoughthisclassificationhasbeenshowntohavesignificantproblemswithintra-observerandinter-observervariabilityand reproducibility,11,12 it remains the most widely-usedclassificationofproximalhumerusfractures. TheAOclassification13,14(Fig.4)emphasizesthevas-cularsupplytothearticularsegment.Thisclassificationisgenerallyonlyusedforreportingpurposesintheliterature,but may have more significance in identifying specificfracturepatterns.AOTypeAfracturesareunifocal,usually

involvingthegreatertuberosityorsurgicalneckandhavenovascularinterruptiontothearticularsegment.TypeBfracturesarebifocal,includesomefracture-dislocations,andhaveanincreasedriskofavascularnecrosis.TypeCfracturesincludeallintra-articularanatomicalneckfrac-tures, includinghead-splitting fractures.These fracturesinvolvetotalvasculardissociationofthearticularsegmentandhaveahighriskofavascularnecrosis.Therearead-ditionalsubdivisionstofurtherdescribethefractures,butduetoboththeclassification’scomplexityandthefactthatithasnotyetbeen shown tobepredictiveof long-termoutcomes,itsuseremainsuncommon.

Current Treatment RecommendationsThecontroversyregardingappropriatetreatmentofproxi-malhumerusfracturesincreasesasthecomplexityofthefractureincreases.Non-displacedorminimallydisplacedfracturesarereportedtocompriseanywherefrom49%to85%ofallproximalhumerusfractures.2-4Clearly,intheelderly,non-operativemanagementoftheseinjuriesistherecommendedtreatment.Thecontroversybeginswhendis-placedfracturesareconsidered.Currenttrendsinorthopae-dicshavefavoredoperativemanagementofdisplacedtwo-,three-,andfour-partfractures.Recommendationsformostdisplaced two- and three-part fractures include internalfixation,withpossibleprostheticreplacementinthree-partfracturesthatarenotamenabletoreconstruction.15-18Theseincludefracturesthatareseverelycomminutedorthatoccurinveryosteopenicbone.Intheelderly,four-partfracturesaregenerallybesttreatedwithhemiarthroplasty,withtheexceptionofthevalgusimpactedfour-partfracture.19,20This

Figure 1Deformingforcesontheproximalhumerus.Directionofarrowsshowsdirectionofdeformitycausedbyeachmuscle.

Figure 2Bloodsupplyoftheproximalhumerus.

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particular fracture pattern has a significantly lower rateofavascularnecrosisthanotherfour-partfractures(20%versusupto90%)andanattemptatlimitedinternalfixation

isrecommended.19Ifadequatefixationisnotpossible,thentreatmentwithhemiarthroplastyshouldproceed. Many different types of internal fixation have been

Figure 3Radiographicshoulder“traumaseries”including:APoftheshoulder(AandB notethelackofoverlapofthehumeralheadontheglenoidascomparedtotheshoulderviewseenonanAPchestx-ray);C, scapularYview;andD, axillaryview.

C

D

BA

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described,andpapersaredispersedthroughoutthelitera-turebothsupportingandcondemningalmosteverytypeoffixation.Discussingtheindicationsandcontraindicationsofthemallisbeyondthescopeofthisreview,butfollowingaremanyofthesefixationoptions:tensionbandwiring16,21;modifiedtensionbandwiringwithEndersrods22;closedreductionandpercutaneouspinning23;intramedullarynail-ing24;andopenreductioninternalfixationwithavarietyofplate-and-screwconstructs,includingstandardT-plates,18,25bladeplates,17and thenewer lockingproximalhumerusplates. Complications of proximal humerus fractures canderivefromboththefractureitselfandfromitstreatment.One of the most devastating of these complications isavascularnecrosis(AVN).ThehighestrateofAVNoccurswithfour-partfractures,and,aspreviouslystated,maybe

ashighas90%.Itcanalsooccurinthree-partfractures,butsinceonlyaportionoftheheadisinvolved,theAVNmaynotbeasclinically significant.However,operativetreatment can exacerbate this, as increased stripping offracturefragmentsduringopenreductioncanincreasetheproportionoftheheadthatisaffectedbyAVN.17,26Othercomplicationsare related to the fact thatanyattemptatinternalfixationinvolvesattemptingtogetadequatebonypurchaseinosteopenicbone.Thesecomplicationsincludemultipletypesofhardwarefailuresuchasscrewcutout,failureofplatefixation,andbackingoutofintramedullarynails,anyofwhichcanresult inbonycollapseand lossofreduction(Fig.5).Aswithall fractures, there isalsoalwaystheriskofmalunion,nonunion,neurologicinjury,and vascular injury, all possible either with or withoutoperativeintervention.

Figure 4AOclassificationofproximalhumerusfractures.

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Are We Operating on Too Many Proximal Humerus Fractures in the Elderly?Astheliteratureoverthepasttwodecadeshastendedtosupport,operativemanagementofdisplacedtwo-part,andmost three-,and four-part fractures,even in theelderly,it is important to critically review the literature regard-ing these injuries.A review of the literature to try todeterminethenaturalhistoryofnon-operativetreatmentof proximal humerus fractures reveals that many of therepeatedlyquotedstudiesaredecadesoldwithmultipleflawsandmanyotheraspectsthatmakedistillingthemallintoasinglerecommendationinappropriate.Thesestud-iesfrequentlyhavedifferentrehabilitationprotocolsnotonly in a study-to-study comparison, but oftenbetweenpatientsgroupswithinthesamestudy.Mostofthestudiesarenonrandomized,retrospective,comparative,andbasedonsmallserieswithnocontrols.9,10Manyhaveinclusion

criteria thatallowtheresultsofnon-operative treatmentoflow-energyfracturesinelderlypatientstobecombinedwith those of young patients with high-energy injuries.Widelyvaryinginjurytypesareoftencombined.Mostim-portantly,inthiseraofevidence-basedmedicine,inmanyofthesestudies,whenoutcomeswereactuallyevaluated,avarietyofoutcomemeasureswereused,butmostofthemwerenotvalidated.9

Asystematicreviewoftheliteratureontreatmentofthree-andfour-partproximalhumerusfracturesbyMisraandcolleagues10lookedat147comparativetrialsandcaseseriesoverthe30-yearperiodfrom1969to1999.Inclusioncriteriaforreviewincludedstudiesevaluatingthree-andfour-part fractures in skeletally mature patients, with aminimum of 15 patients enrolled in each study, treatedwithin48hoursof injury,withaminimumof6monthsoffollowupandat least85%patientfollowup.Ofthese

Figure 5This65-year-oldpatienthadanopenproximalhumerusfracture-dislocation(A)andunderwentirrigationdebridementandoperativefixationinitiallywithmodifiedtensionbandwiring(B).Thisfixationfailed(C,APveiw)andwasrevisedtoabladeplate(D),whichalsofailed(E).Thepatientdevelopedapost-operativeinfectionrequiringnumerousrepeatdebridements,buteventuallywentontohealwithantibioticbeadsbutnohardwareinplace(F).

A B C

D E F

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147studies,only24wereeligiblefortheauthors’review.Twenty-onewerecaseseries,threewerecomparativetri-als,andonlytwowererandomized,controlledtrials.Theauthorslookedatnumerousfactorstoattempttoderiveanyconclusionsfromtheirmeta-analysis.Theonlyconclusionstheywereabletodrawwere:1.conservativemanagementcomparedtoeitherfixationorarthroplastyresultedinmorepainandpoorerrangeofmotion,althoughthedifferenceinrangeofmotionwhencomparingconservativemanage-menttofixationwasnotsignificant;and,interestingly,2.restorationof anatomywasnot shown to correlatewithbetter functionaloutcome.These investigatorswereun-abletoreachanyotherconclusionsbasedontheliterature,despitethelargenumberofstudiestheyreviewed. TheCochranedatabaseofsystematicreviews,acol-lection of evidence-based medicine databases, containsa reviewof interventions forproximalhumerus fracturesoriginally performed in 2001, and updated in 2002 and2003.9,27,28Evenwithupdates,only12randomizedstudiesonproximalhumerusfractureswerefoundintheliterature.Allweresmall,withthelargestinvolvingonly86patients.Eight evaluated conservative treatment, three comparedconservative treatment with surgery, and one comparedtwosurgicaltechniques.OneofthemajorconclusionsfromboththisreviewandthatofMisraandcolleagues10isthatnoevidence-baseddecisionsregardingappropriatetreatmentofproximalhumerusfracturescanbemadebasedonthecurrentliterature. Inoneofthefewrandomized,prospectivestudiesintheliterature,Zytoandassociateslookedatthree-andfour-partfracturesin40patientswithameanageof74years,comparingtensionbandwiringtoconservativetreatment.21UsingtheConstantscore,29pain,rangeofmotion,power,andactivitiesofdailylivingwereassessed.Theseinvestiga-torsfoundnosignificantdifferenceinfunctionafter1yearbetween theoperativeandnon-operativegroups,withnostatisticallysignificantdifferencesinpain,rangeofmotion,abduction/flexionpower,orabilitytoperformactivitiesofdaily living. In both groups, little improvement in theseoutcomeswasseenafter1year.Surgerydidimprovethepositionofthefracturefragments,butthisdidnotcorrelatewithanyimprovementinfunctionaloutcomecomparedtothe non-operative patients, plus surgery resulted in morecomplications.Theseinvestigatorsconcludedthat,asout-comeswere similarbutoperative treatmenthad ahighercomplication rate, conservative treatment should be con-sideredfordisplacedthree-partfractures.Sinceonlythreepatientsinthestudyhadfour-partfractures,theauthorsfelttheir sample sizewas too small todrawanyconclusionsaboutthisfracturetype.However,theydidnotethatofthetwopatients treatednon-operatively,bothhadacceptablefunctionaloutcomes. Ilchmann and coworkers7 performed a retrospectivereviewof34patients,withameanageof70years,inwhomthree-andfour-partfracturesweretreatedeithernon-opera-

tivelyorwithtension-bandwiring.Inthree-partfractures,theyfoundbetterpainreliefandfunctionwithnon-operativemanagement,althoughbothformsoftreatmentresultedindecreasedrangeofmotion.Allfour-partfractureshadanoverallpooroutcomeregardlessoftreatmentmodality,buttension-bandwiringdidseemtoimprovefunctionandmo-tionintheseinjuries.However,theseinvestigatorsrecom-mendedinternalfixationoffour-partfracturesonlyforthevalgus-impactedfractures.Otherwise,theirrecommendationwasforprostheticreplacement. AretrospectivestudybyZyto5lookedat17three-andfour-part fractures in15patients,withameanageof66years,whoweretreatednon-operativelyandfollowedforaminimumof10years.Althoughthesamplesizewassmall,thisstudyisuniqueinitslong-termfollow-up.AllpatientshadlowConstantscores,butallalsohadhighacceptanceoftheirshoulderconditiondespitedecreasedrangeofmotionandweakness.Thiswasbelievedtobemostlikelyduetothefactthatonlyfourpatientsreportedmildpain,andtherest,includingallofthepatientswithfour-partfractures,hadnopain.Asradiographsshowedthatonly3outof17ofthesefractureshadacceptablealignment,andonly7showedthegreatertuberosityinanacceptableposition,theauthorcon-cludedthattherewasnoclearrelationshipbetweenfracturereduction,functionaloutcome,andpatientsatisfaction. In 2001, Court-Brown and colleagues2 revisited theNeer classification in an epidemiological study of 1,027proximal humerus fractures.They concluded that certainfracturepatternsweremissedusingtheNeerclassification,includingthemostcommonfracturetypeseen:theimpactedbifocalfracture(AO11-B1.1)(Fig.6).Thisfracturepatternrepresentednearly15%ofallproximalhumerusfractures,while Neer three- and four-part fractures combined ac-countedforonly13%ofproximalhumerusfractures,withthe rare four-part fracture occurring in only 3% of the1,027fracturesevaluated.ThistypeB1.1fracturemayberepresentedbyaminimallydisplacedfracture,adisplaced

Figure 6AOTypeB1.1impactedbifocalfracture.

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two-partsurgicalneckfracture,adisplacedtwo-partgreatertuberosityfracture,orathree-partvariantwithsignificantdisplacementofboththesurgicalneckandgreatertuberos-itywithvalgusimpaction(Fig.7).Inaretrospectivereviewevaluatingthisspecificfracturepattern,Court-Brownandassociates6reviewed125patientswithB1.1fractureswithameanageof71yearswhoallhadavalgusimpactedB1.1fracture treatednon-operatively.All fracturesunitedwith80.6%goodtoexcellentresultsatoneyearusingtheNeercriteria.Therewasagreaterimprovementinsubjectivethanobjectivemeasures.Thepatientsaveragedonly75%abduc-tionandflexionpowerandhadmarkedlylimitedinternalandexternalrotationafteroneyear,withmeanpowerjustover70%ofnormal.However,subjectivelypatientsperceivedtheirstrengthasgreaterthan90%ofnormalinallfracturepatternsexceptthethree-partvariant,inwhichpowerwasstillperceivedatgreaterthan85%ofnormal.Fullglenohu-meralmovementorpowerclearlyisnotrequiredforelderlypatients to return to routine activities. Comparing theirresultstothoseofotherstudiesevaluatingbothoperativeandnon-operativemanagement,7,17,20,21,24,30theinvestigators

concludedthattherewaslittleevidencethatoperativetreat-mentofimpactedvalgusthree-partfracturesintheelderlyprovidesanybenefitandtheyrecommendednon-operativemanagement.

Figure 7Different typesofB1.1 fracturesincludingaminimallydisplacedfracture(A),a displaced two-part surgical neck fracture(B), a displaced two-part greater tuberos-ityfracture(C),orathree-partvariantwithsignificantdisplacementofboththesurgicalneckandgreatertuberositywithvalgusim-paction(D).(Reprintedwithpermissionfrom:Court-BrownCM,CattermoleH,McQueenMM: Impacted valgus fractures (B1.1) ofthe proximal humerus:The results of non-operative treatment. J Bone Joint Surg Br84(4):504-508, 2002.)

A

DC

B

Figure 8AOTypeA3.2translatedtwo-partfracture.

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Despite the large number of studies addressingmanagement of displaced proximal humerus fractures inthe literature, most of them refer to three- and four-partfractures.A prospective study of 126 displaced two-partfracturesfollowedforfiveyearsinpatientswithameanageof72yearsshowedinterestingresults.8Allpatientshadatranslatedtwo-partfracture(AO11-A3.2)(Fig.8),which,basedontheinvestigators’previousepidemiologicalstudy,2represents12.7%ofallproximalhumerusfractures.Mostofthepatientshadgreaterthan67%translationplusposteriorangulation.Allfracturesweretreatednon-operatively;allunited(Fig.9)andallhadahighNeerscoreatoneyear.Aswithpreviousstudies, thepatients’subjectiveviewoftheirprogresswasbetterthantheobjectivemeasures.Goodorexcellentresultswereseenin64.5%ofpatients.Therewasnocorrelationbetweentranslationorangulationandapatient’sabilitytoreturntodailyactivities.Thesepatientswere compared to anoperative cohort, alsowith at least66%translation,andtherewasfoundtobenodifferenceinNeerscoresatoneyear.Surgerydidnotimproveoutcomesregardless of the amount of initial translation. Based ontheseresults,theseinvestigatorsdonotrecommendinternalfixationofanytwo-partfracturesintheelderlyregardlessofdegreeofinitialdisplacement.

ConclusionsDespitethelargenumberofretrospectivereviewsandcaseseriesdetailingresultsofoperativetreatmentofproximalhumerus fractures, newer literature is trending towardsupportofnon-operative treatmentofdisplaced two-partfractures and most three-part fractures, as there appearstobenodifferenceinfunctionaloutcomeswithoperativeversusnon-operativetreatment.Thetreatmentofchoiceforfour-partfracturesremainsunclear–partlyduetotheirlowincidenceinmoststudies–butcurrentliteraturecontinuestosupportoperativetreatmentoffour-partfracturesintheelderly.Limitedopenreductioninternalfixationisrecom-mended for the stable four-part valgus impacted fractureandhemiarthroplastyformoreunstablefour-partfractures

includinghead-splittingfractures,anatomicneckfractures,and head impression fractures. Results in the literaturecontinuetoshowthat,althoughnoonehasmatchedNeer’sresults,hemiarthroplastyforfour-partfracturescanprovidepredictablepainrelief,butunpredictablefunction.31,32Well-designed,multicenter,prospective,randomizedstudiesareneededtoprovidetrueevidence-basedtreatmentrecommen-dationsforthesecomplexandcontroversialinjuries.

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A B

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32. Mighell MA, Kolm GP, Collinge CA, et al: Outcomes ofhemiarthroplasty for fractures of the proximal humerus. JShoulderElbowSurg12(6):569-577, 2003.