ASTM_F_2033_-_12.pdf

Designation:F203312Standard Specification forTotal Hip Joint Prosthesis and Hip Endoprosthesis BearingSurfaces Made of Metallic,Ceramic,and PolymericMaterials1This standard is issued under the fixed designation F2033;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers the requirements for the mat-ing bearing surfaces of total hip prostheses and hip endopros-theses.More specifically,this specification covers hip jointreplacement of the ball-and-socket configuration.1.2 This specification covers the sphericity,surface finishrequirements,and dimensional tolerances for the sphericalarticulating metallic or ceramic femoral heads of total hip jointprostheses.1.3 This specification covers the sphericity,surface finishrequirements,and dimensional tolerances for the sphericalconcave mating surface of metallic and ceramic acetabularcomponents,including the inner polymeric bearing surface ofbipolar heads,and the surface finish requirements and dimen-sional tolerances for the spherical concave mating surface ofpolymeric acetabular components.1.4 This specification covers the sphericity and surfacefinish requirements for the spherical metallic or ceramicfemoral heads of hip endoprostheses,and the outer bearingsurface of bipolar heads.1.5 This specification is intended for standard practiceregarding the design of total hip joint bearing surfaces.Additionally,the tolerances imposed on the polymeric portionof the bearing surface are intentionally large due totemperature-induced size changes and other manufacturingconcerns.Some manufacturing methods or designs may inten-tionally reduce the diameter of the polymeric bearing to moreclosely mate with the diameter of the head.1.6 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.2.Referenced Documents2.1 ISO Documents:2ISO 4287/1 Surface RoughnessTerminologyISO 4291 Methods for the Assessment of Departure fromRoundness,Measurement of Variations,and RadiusISO 5436 Surface Texture of ProductsCalibration Speci-mens for Stylus InstrumentsISO6318-1985 MeasurementofRoundnessTerms,Definitions,and Parameters of Roundness(Equivalent toBS 3730 Part 1:1987)ISO 7206-1 Implants for SurgeryPartial and Total HipJoint ProsthesisPart I:Classification,Designation ofDimensions,and RequirementsISO 7206-2 Implants for SurgeryPartial and Total HipJoint ProsthesisPart II:Bearing Surfaces Made of Me-tallic and Plastics Materials2.2 ANSI/ASME Document:2ANSI/ASME B46.1-1995 Surface Texture3.Dimensions and Characteristics3.1 Definition:3.1.1 pole of the articulating surfaceThe pole of anarticulating surface is defined by a point at the intercept of therevolution axis of the component and the spherical articulationsurface.3.1.2 equator of the articulating surfaceThe equator ofthe articulating surface is the circle normal to the revolutionaxis of the component,the center of which is the center of thespherical articulating surface.3.1.3 cutoff lengthThe cutoff length defines the maximalvalue of the mean twist of profile irregularities that shall beconsidered in the roughness measurement,that is,with a cutofflength of 0.8 mm,the profile irregularities with a mean twisthigher than 0.8 mm shall not be considered.3.1.3.1 Precise definitions of roughness parameters,cutofflength,and roundness are given in ISO 4287/1,ISO 5436,ISO4291,and ISO 6318:1985.1This specification is under the jurisdiction of ASTM Committee F04 onMedical and Surgical Materials and Devices and is the direct responsibility ofSubcommittee F04.22 on Arthroplasty.Current edition approved Feb.15,2012.Published March 2012.Originallyapproved in 2000.Last previous edition approved in 2005 as F2033 05.DOI:10.1520/F2033-12.2Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.4 stylus tipThe stylus tip is the tip of the measuringdevice(diamond or Focodyn)which measures the surfaceroughness.A stylus has a pseudoconical shape with a hemi-spherical tip.Typical sizes for the tip are 2,5,or 10 m.Theselection of the stylus tip is dependent on the range of theroughness measured.3.2 Total Hip Joint Prosthesis:3.2.1 Femoral Head:3.2.1.1 Wheninspectedvisuallyunder5-dioptermagnification,the bearing surface shall be free from particles,scratches,and score marks other than those arising from thefinishing process.3.2.1.2 sphericityThe metal or ceramic spherical bearingsurface of a femoral hip component shall have a departure fromroundness of not greater than 10 m(390 in.)This shall bemeasured as Zzin accordance with the Minimum Zone CenterMethod