Zimmer® Gender Solutions™

NexGen® High-Flex Implants

Because Women and Men are Different

Something new is taking shape

Womenandmenaredifferent.That’snotnewstothemedicalestablishment.WhatisnewsisthatZimmerisfirstintheorthopaedicindustrytoaddressthisfact…

withtheintroductionoftheZimmer®Gender Solutions™ NexGen®High-FlexImplants.

Whatmakesthemrevolutionaryisthewayinwhichtheycompensateforthemostimportantdifferences

betweenwomen’sandmen’sknees.Itisn’tstrictlyamatterofsize;it’samatterofshape.

Why a woman’s knee?Agrowingbodyofresearchhasledtobreakthroughsindistinctivefemaleandmalediagnosesandtreatments—forconditionsrangingfromheartdiseasetorheumatoidarthritis.Theneedtoaccountforgender-specificsolutionsinorthopaedicsisapparent.

• Orthopaedicsurgeonshavereportedanatomicaldifferencesinwomen’sandmen’skneesforyears.1,2,3,4,5,6,7,8

• Orthopaedicsurgeonsoftenhavetoconsiderintraoperativeadjustmentsduringkneesurgerytoaccommodatewomen’sanatomicaldifferences.4

• Womenaccountfornearlytwo-thirdsofkneearthroplastiesperformedannuallyintheU.S.9,10

• Womenarethreetimesmorelikelythanmentoforegokneearthroplasty.11

It’s all about shape.

Two distinct populations: women and menPioneeringresearchconductedbyZimmerhasmappedtheanatomicaldifferencesbetweenfemaleandmaleknees,12,13layingthefoundationforthedesignanddevelopmentofGender SolutionsHigh-FlexFemoralImplants.

• Three-dimensionalCTdatawascollectedandanalyzedformorethan800femursandpatellas.

• Significantdifferenceswereidentifiedbetweenfemaleandmalekneeanatomy.

• PlottingM/LandA/Pdimensionsofthedistalfemurrevealstwodistinctpopulations:femaleandmale.

Implantdesignsthatdistinguishbetweenfemaleandmaleanatomicaldifferencesallowforimprovedimplantfitandfewerintraoperativeadjustments.

Gender SolutionsHigh-FlexFemoralImplantsaddressthedistinctivedifferencestypicallyfoundinthefemaleanatomy.

“Historically we have shaped the patients to fit the implants. Now we have implants shaped to fit the patients.”

Robert E. Booth, Jr., M.D.

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A/P

Overall A/P (mm)

Mid

-Box

M/L

(mm

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Male Data

Average Male Data

Female Data

Average Female Data

M/L Mid-Box

Mid-box M/L vs. overall A/P

Traditional implant GenderSolutions High-FlexFemoral Implant

Anterior flange thickness Researchhasshownthatthefemalekneehasaless-pronouncedanteriorcondylethanmales.2,13Thisless-pronouncedanteriorcondyleresultsinlessbonebeingresectedfromthefemaleknee:

• 0.8mmlessonthelateralcondyle(p<0.02).13

• 1.3mmlessonthemedialcondyle(p<0.01).13

Gender SolutionsHigh-FlexFemoralImplantsaddressthedistinctiveanteriorcondyledifferencesby:

• Reducingtheanteriorflangethicknessoftheimplant.

• Recessingthepatellarsulcus.

• RetainingtheclinicallysuccessfulNexGenpatellararticulation.

• Avoidingoverstuffingthatmaylimitpostoperativerangeofmotion14,15thatcanoccurwhenplacingatraditionalimplantonaresectedfemaleknee.

It’s all about shape –Modified Anterior Flange

Female Male DifferenceLateral condyle height (mm) 10.1 10.9 0.8Medial condyle height (mm) 5.1 6.4 1.3

Male resection Female resection

GenderSolutions High-FlexFemoral Implant

Traditional implant

Anterior flange widthThefemoralanteriorresectionofthefemaleboneisnarrowerthanthemalefemoralanteriorresection.

Female resectionMale resection

Increased Trochlear Groove Angle Patellarmaltrackingremainsaconcern— particularlywithfemales— followingtotalkneearthroplasty.5

ResearchdocumentsthatwomenhaveastatisticallysignificanthigherQ-anglethanmen.6,7,8

Gender SolutionsHigh-FlexFemoralImplantsreplicatethedistinctQ-angledifferencebyincreasingthetrochleargrooveangleoftheimplantthreedegrees.

Traditional implant GenderSolutions High-FlexFemoral Implant

“Twenty-five years ago TKA femoral components were symmetrical. As we recognized the need to improve patellar tracking, industry responded by offering left and right components. Providing an implant that better accommodates the patellar tracking typical of the female patient is just one of the design innovations that the GenderSolutionsNexGen High-Flex Femoral Components offers.”

Aaron G. Rosenberg M.D., Professor of Orthopaedic Surgery

Male

Female

Whenatraditionalimplantisplacedontoaresectedfemaleknee:

• Theimplantmayoverhangtheboneatthedistal,anterior,andposteriorM/Linterfaces,whichmayleadtosoft-tissueirritationandaffectsoft-tissuebalancing.1,3,4

• Thesurgeonmaybefacedwithintraoperativeadjustmentstocompensatefortheoverhang.

Gender SolutionsHigh-FlexFemoralImplantshavebeennarrowedmediolaterally.

Thisallowssurgeonstoaddressthefemalepopulationwithunprecedentedaccuracy.

CTdatadocumentsdistinctiveshapedifferencesinfemaleandmaledistalfemurs.12,13

Femalefemursare:

• Moretrapezoidal-shaped.

• NarrowerintheM/LdimensionwhencomparedtoamalefemurofthesameA/Pdimension.

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Overall A/P (mm)

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M/L

(mm

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A/P

Male Data

Zimmer NexGen High-Flex Femorals

Female Data

Zimmer Gender Solutions High-Flex Femorals

M/L Mid-Box

Female and male aspect ratio

It’s all about shape –Modified ML/AP Aspect Ratio

Female-to-male comparison

Femoral mapping —applying the scienceToaddresstheissueofoverhanginfemalekneearthroplasty,Zimmerhasdevisedauniquepatentpendingmethodforpredeterminingthecontourofaresectedboneandthefitofanimplantonthebone,andappliedthisnovelmethodinitsdevelopmentoftheGender Solutions High-FlexFemoralImplant.

2) This shape is then extracted… 3) …and unfolded into a two-dimensional profile.

4) The resection planes of the female bone are rendered in a two-dimensional profile and overlayed on the implant profile.

6) Additional female data sets are then added to increase the statistical accuracy.

7) A two-dimensional female profile is created…

8) …that replicates the shape of the female bone.

1) The three-dimensional inner box shape of the traditional implant is determined.

5) Arrows indicate the areas where traditional implants overhang the female bone.

Traditional implant overhangs female bone

GenderSolutionsHigh-Flex Implant on female bone showslittle to no overhang

Gender Solutions NexGen CR-Flex and LPS-Flex

Contact your Zimmer representative or visit us at www.zimmer.com

• BuiltuponZimmer’s30-yearsofclinicalsuccesswithtotalkneearthroplasty.

• Safelyaccommodateshighflexion —upto155degrees—forpatientswiththeabilityanddesiretodoso.

• CanbeimplantedusinganyZimmersurgicaltechniqueincludingZimmer ® Minimally Invasive Solutions™(MIS™)Procedures.

Zimmer Gender Solutions High-FlexFemoralImplantsarespecificallydesignedtoalleviatekneepain,restoremobility,andofferoptimalfitandfunctionality.Toachievethesegoals,Gender SolutionsHigh-FlexFemoralImplantsaddressthedistinctivecharacteristicstypicallyseenwithawoman’sknee.Because women and men are different.

References:

1.HittK,ShurmanIIJ,GreeneK,etal.Anthropometricmeasurementsofthehumanknee:correlationtothesizingofcurrentkneearthroplastysystems.J Bone Joint Surg.2003;85:155-122.

2.PoilvachePL,InsallJN,ScuderiGR,Font-RodriguezDE.Rotationallandmarksandsizingofthedistalfemurintotalkneearthroplasty,Clin Orthop.1996;331:35-46.

3.VaidyaSV,RanawatCS,AroojisA,LaudNS.AnthropometricmeasurementstodesigntotalkneeprosthesesfortheIndianpopulation.J Arthroplasty.2000;15(1):79-85.

4.ChinKR,DaluryDF,ZurakowskiD,ScottRD.Intraoperativemeasurementsofmaleandfemaledistalfemursduringprimarytotalkneearthroplasty.J Knee Surg.2002;15(4):213-214.

5.CsintalanRP,SchulzMM,WooJ,McMahonPJ,LeeTQ,GenderDifferencesinPatellofemoralJointBiomechanics,Clin Orthop.September,2002;402:260-269.

6.AgliettiP,InsallJN,CerulliG.Patellarpainandincongruence.I:Measurementsofincongruence.Clin Orthop.1983;176:217-224.

7.HsuRWW,HimenoS,CoventryMB,ChaoEYS.Normalaxialalignmentofthelowerextremityandloadbearingdistributionattheknee,Clin Orthop.1990;255:215-227.

8.WoodlandLH,FrancisRS.Parametersandcomparisonsofthequadricepsangleofcollege-agedmenandwomeninthesupineandstandingpositions.American Journal of Sports Medicine.1992;20:208-211.

9.U.S.DepartmentofHealthandHumanServices,CentersforDiseaseControlandPrevention,NationalCenterforHealthStatistics.2003NationalHospitalDischargeSurvey,AdvanceDataNo.359.July8,2005;Table8:14.

10.U.S.DepartmentofHealthandHumanServices,CentersforDiseaseControlandPrevention,NationalCenterforHealthStatistics.2003NationalHospitalDischargeSurvey,AdvanceDataNo.359.July8,2005;Table10:16.

11.HawkerG,WrightJ,CoyteP,etal.,Differencesbetweenmenandwomenintherateofuseofhipandkneearthroplasty,The New England Journal of Medicine.342:1016-1022,2000.

12.MahfouzM,BoothRJr,Argenson,J,Merkl,BC,AbdelFatahEE,KuhnMJ.Analysisofvariationofadultfemorausingsexspecificstatisticalatlases.Presentedat:ComputerMethodsinBiomechanicsandBiomedicalEngineeringConference;2006.

13.DataonfileatZimmer14.ScottNW.Pearlsonavoidanceandtreatmentofintraoperativeand

postoperativecomplications–exposureofthestiffknee.Presentedat:AmericanAssociationofHipandKneeSurgeons,KneeSocietySpecialtyDay;March25,2006.

15.BengsBC,ScottRD.Theeffectofpatellarthicknessonintraoperativekneeflexionandpatellartrackingintotalkneearthroplasty.J Arthroplasty.2006;21(5):650-655.

GenderSolutionsNexGen LPS-Flex

GenderSolutionsNexGen CR-Flex

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