1、Designation: F2565 13Standard Guide forExtensively Irradiation-Crosslinked Ultra-High MolecularWeight Polyethylene Fabricated Forms for Surgical ImplantApplications1This standard is issued under the fixed designation F2565; the number immediately following the designation indicates the year oforigin
2、al 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 guide covers extensively crosslinked ultra-highmolecular wei
3、ght polyethylene (UHMWPE) materials (fabri-cated forms) that are produced starting with virgin resinpowders and consolidated forms meeting all the requirementsof Test Method F648.1.2 This guide does not cover fabricated forms of ultra-highmolecular weight polyethylene which have received only gaspla
4、sma, ethylene oxide, or less than 40 kGy ionizing radiationtreatments, that is, materials treated only by historical steril-ization methods.1.3 This guide pertains only to UHMWPE materials exten-sively crosslinked by gamma and electron beam sources ofionizing radiation.1.4 The specific relationships
5、 between these mechanicalproperties and the in vivo performance of a fabricated formhave not been determined. While trends are apparent, specificproperty-polymer structure and polymer-design relationshipsare not well understood. These mechanical tests are frequentlyused to evaluate the reproducibili
6、ty of a fabrication procedureand are applicable for comparative studies of different materi-als.1.5 The following precautionary caveat pertains only to thetest method portion, Section 5, of this guide. This standarddoes not purport to address all of the safety concerns, if any,associated with its us
7、e. It is the responsibility of the user of thisstandard to establish appropriate safety and health practicesand determine the applicability of regulatory limitations priorto use.2. Referenced Documents2.1 ASTM Standards:2D638 Test Method for Tensile Properties of PlasticsD695 Test Method for Compres
8、sive Properties of RigidPlasticsD1898 Practice for Sampling of Plastics (Withdrawn 1998)3D2765 Test Methods for Determination of Gel Content andSwell Ratio of Crosslinked Ethylene PlasticsE647 Test Method for Measurement of Fatigue CrackGrowth RatesF619 Practice for Extraction of Medical PlasticsF64
9、8 Specification for Ultra-High-Molecular-Weight Poly-ethylene Powder and Fabricated Form for Surgical Im-plantsF748 Practice for Selecting Generic Biological Test Methodsfor Materials and DevicesF749 Practice for Evaluating Material Extracts by Intracuta-neous Injection in the RabbitF756 Practice fo
10、r Assessment of Hemolytic Properties ofMaterialsF763 Practice for Short-Term Screening of Implant Materi-alsF813 Practice for Direct Contact Cell Culture Evaluation ofMaterials for Medical DevicesF895 Test Method forAgar Diffusion Cell Culture Screeningfor CytotoxicityF981 Practice for Assessment of
11、 Compatibility of Biomate-rials for Surgical Implants with Respect to Effect ofMaterials on Muscle and BoneF2003 Practice for Accelerated Aging of Ultra-High Mo-lecular Weight Polyethylene after Gamma Irradiation inAir1This guide is under the jurisdiction of ASTM Committee F04 on Medical andSurgical
12、 Materials and Devices and is the direct responsibility of SubcommitteeF04.11 on Polymeric Materials.Current edition approved July 15, 2013. Published August 2013. Originallyapproved in 2006. Last previous edition approved in 2006 as F2565-06. DOI:10.1520/F2565-13.2For referenced ASTM standards, vis
13、it the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright AS
14、TM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1F2102 Guide for Evaluating the Extent of Oxidation inUltra-High-Molecular-Weight Polyethylene FabricatedForms Intended for Surgical ImplantsF2183 Test Method for Small Punch Testing of Ultra-HighMol
15、ecular Weight Polyethylene Used in Surgical ImplantsF2214 Test Method forIn Situ Determination of NetworkParameters of Crosslinked Ultra High Molecular WeightPolyethylene (UHMWPE)F2381 Test Method for Evaluating Trans-Vinylene Yield inIrradiated Ultra-High Molecular Weight PolyethyleneFabricated For
16、ms Intended for Surgical Implants by In-frared SpectroscopyF2625 Test Method for Measurement of Enthalpy of Fusion,Percent Crystallinity, and Melting Point of Ultra-High-Molecular Weight Polyethylene by Means of DifferentialScanning CalorimetryF2759 Guide for Assessment of the Ultra High MolecularWe
17、ight Polyethylene (UHMWPE) Used in Orthopedic andSpinal Devices2.2 ISO Standards:4ISO 10993 Biological Evaluation of Medical Devices, Parts1-12ISO 527 PlasticsDetermination of Tensile PropertiesPart 1: General Principles3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 fabricate
18、d formany bulk shape of UHMWPE, fab-ricated from the virgin polymer powder and used during theprocess of fabricating surgical implants prior to crosslinking,packaging, and sterilization.3.1.2 extensively crosslinked UHMWPEUHMWPE mate-rial that has been subjected to total doses of gamma and/orelectro
19、n beam ionizing irradiation greater than 40 kGy for thepurpose of generating crosslinks within the material.3.1.3 ionizing radiationgamma or high energy electronradiation.3.1.4 crosslinkingthe process by which ionizing radiationproduces chemical bonds between two UHMWPE molecules.4. Sampling4.1 Wher
20、e applicable, the requirements of this guide shallbe determined for each lot of powder and fabricated form bysampling sizes and procedures according to Practice D1898,oras agreed upon between the purchaser and seller.5. Extensively Crosslinked UHMWPE Fabricated FormRequirements5.1 Compositional Requ
21、irements:5.1.1 The virgin powder and fabricated forms from whichthe extensively crosslinked material is manufactured shall meetall the requirements of Practice F648.5.2 Physical Requirements:5.2.1 The manufacture of an extensively crosslinked UHM-WPE material may be accomplished many different ways.
22、Therefore, each manufacturer of such material(s) has devel-oped its own proprietary method(s) for doing so. The end resultof this variation is that some of the mechanical properties ofextensively crosslinked materials currently used for orthopae-dic implant applications exhibit a wide range of value
23、s. Whenthis is coupled with the fact that the limiting value for anyspecific mechanical property necessary for clinical success isyet unknown, a listing of such data for these materials iscurrently impractical. It is more useful and practical to describestandard methods suitable for characterizing t
24、hese materials.5.2.2 UHMWPE Mechanical and Physical AssessmentsPart 1The tests shown in Table 1 should be conducted on theextensively crosslinked UHMWPE. Alternative tests may beconsidered with documented analysis and rationale.5.2.3 Mechanical and Physical AssessmentPart 2Thetests shown in Table 2
25、should be conducted on the extensivelycrosslinked UHMWPE. Alternative tests may be considered,such as electron spin resonance (see Appendix X1) withdocumented analysis and rationale.5.2.4 Preclinical SimulationFunctional testing on the fin-ished UHMWPE component that simulates clinical functionsand
26、known failure modes should be considered. Testing thatshould be considered include creep, accelerated aging, orshelf-life testing, or combinations thereof, functional fatigueloading, and wear as described in Guide F2759. Practice F2003should be considered for determining relative oxidative stabil-it
27、y.6. Biocompatibility6.1 This material has been shown to produce a well char-acterized level of biological response following long termclinical use in humans. The results of these studies and theclinical history indicate an acceptable level of biologicalresponse in the applications in which the mate
28、rial has been4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.TABLE 1 UHMWPE Mechanical and Physical Assessments, Part 1Test Description MethodTensile Strength D638 or ISO 527UltimateYieldElongation, % D638Izod impact strength, kJ/m2F648, Ann
29、ex A1Elastic modulus D638Compression modulus, MPa D695Thermal properties F2625Percent crystallinityMelting temperatureTABLE 2 Mechanical and Physical Assessment, Part 2Test Description MethodSmall punch ultimate load, N F2183Fatigue crack propagation E647Swell ratio D2765 or F2214Oxidation index (OI
30、), surface oxidation index(SOI)and OI MaximumF2102t-Vinylene content, trans-vinylene index(TVI)F2381F2565 132utilized. When new applications of the material, or modifica-tion to the material or physical forms of the materials are beingcontemplated, the applicable parts of ISO 10993 and PracticeF748
31、should be considered and testing considered as describedin Practices F619, F749, F756, F763, F813, and F981 as wellas Test Method F895.7. Keywords7.1 fabricated forms; powdered form; ultra-high molecularweight polyethyleneAPPENDIX(Nonmandatory Information)X1. RATIONALEX1.1 This guide is intended to
32、describe the minimum set ofrequired test methods that are necessary to fully characterizethe physical, chemical, and mechanical behavior of anirradiated, extensively crosslinked UHMWPE material that isintended for use in orthopedic or spine implants.X1.2 In 1995, the Food and Drug Administration pub
33、lisheda guidance document for the characterization of UHMWPEmaterials (1).5Since that time, extensively crosslinked mate-rials have been developed, and the 1995 FDA guidancedocument has been withdrawn, but is available upon request.Therefore, one of the expected uses for the current ASTMguide is to
34、provide guidance to regulatory bodies and orthope-dic manufacturers by identifying a standardized set of testmethods for characterizing extensively crosslinked UHMWPEmaterials.X1.3 While it is currently possible to identify which testmethods are necessary for characterizing extensively cross-linked
35、UHMWPE, it remains impractical to assign minimumacceptable values for each test method. For many of thesemethods, the association between the properties measured andclinical performance is currently unknown. Therefore, it is theresponsibility of the manufacturer to develop its own minimumdataset for
36、 its process of producing extensively crosslinkedUHMWPE, using the test methods in this guide for processvalidation.X1.4 Although the test methods listed in Table 1 areintended to be the minimum data set necessary for processvalidation with an extensively crosslinked UHMWPE material,they are not all
37、 intended to be performed routinely duringquality control. It is the responsibility of the manufacturer todevelop a specification for its material, and to identify which ofthe test methods listed in Table 1 will be performed routinelyfor quality control purposes.X1.5 Fatigue resistance is a desirabl
38、e property for exten-sively crosslinked UHMWPE materials. Table 1 lists fatiguecrack propagation tests, in accordance with Test Method E647,as the reference test method for this attribute. However, certainlinear elastic fracture mechanics principles (for example, theassumption of the plane strain co
39、nditions), which underlie themethods of fatigue crack propagation assessment outlined inTest Method E647, are not strictly applicable to ductilepolymers, such as UHMWPE, regardless of whether or not thematerial has been extensively crosslinked. Therefore, theinterpretation of fatigue crack propagati
40、on test data for UHM-WPE is currently limited, because the results of such tests arespecimen-geometry specific. Furthermore, there is some debatein the literature about which are the most useful properties tomeasure for highly crosslinked UHMWPE during fatigue crackpropagation testing, such as the e
41、xponent during the Parisregime and/or K inception value (2-4). If, in the future, amore relevant fatigue characterization test can be identified forUHMWPE, it may be incorporated into Table 1.X1.6 Similarly, analysis of free radicals is also considered tobe important for extensively crosslinked mate
42、rials. Electronspin resonance spectroscopy is currently considered to be themethod of choice for quantifying the concentration and type offree radicals in UHMWPE, however a standard has not yetbeen developed for this purpose. Until such time as a standardmethod for measuring free radicals in UHMWPE
43、has beencreated (at which point Table 1 will be updated), the reader isreferred to the literature for details related to this procedure (5).X1.7 Although this guide lists a minimum number ofcharacterization tests for an extensively crosslinked UHMWPEmaterial in Table 1, this guide does not purport t
44、o address all ofthe functional testing that a manufacturer should perform toevaluate the fatigue and wear performance of a particulardevice. Device testing is recognized to be crucial for UHM-WPE implants, but is beyond the scope of this guide.5The boldface numbers in parentheses refer to the list o
45、f references at the end ofthis standard.F2565 133REFERENCES(1) Food and Drug Administration, “Data Requirements for Ultra-HighMolecular Weight Polyethylene (UHMWPE) Used in OrthopedicDevices,” Orthopedic Devices Branch, Rockville, MD, March 28,1995.(2) Gencur, S. J., Rimnac, C. M., and Kurtz, S. M.,
46、 “Fatigue CrackPropagation Resistance of Virgin and Highly Crosslinked, ThermallyTreated Ultra-High Molecular Weight Polyethylene,” Biomaterials,27, 2006, pp. 1550-1557.(3) Bradford, L., Baker, D., Ries, M. D., and Pruitt, L. A., “Fatigue CrackPropagation Resistance of Highly Crosslinked Polyethylen
47、e,” ClinOrthop Relat Res, 429, 2004, pp. 68-72.(4) Baker, D. A., Bellare, A., and Pruitt, L., “The Effects of Degree ofCrosslinking on the Fatigue Crack Initiation and Propagation Resis-tance of Orthopedic-Grade Polyethylene,” J Biomed Mater Res, 66,2003, pp. 146-154.(5) Jahan, M. S., “ESR Insights
48、into Macroradicals in UHMWPE,”Chapter 29, The UHMWPE Biomaterials Handbook: Ultra-HighMolecular Weight Polyethylene in Total Joint Replacements andMedical Devices, Second Edition, S. M. Kurtz, Ed., Elsevier Aca-demic Press, Burlington, MA, 2009.ASTM International takes no position respecting the val
49、idity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to AST
