1、Designation: F 2565 06Standard Guide forExtensively Irradiation-Crosslinked Ultra-High MolecularWeight Polyethylene Fabricated Forms for Surgical ImplantApplications1This standard is issued under the fixed designation F 2565; the number immediately following the designation indicates the year oforig
2、inal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers extensively crosslinked ultra-highmolecular
3、weight polyethylene (UHMWPE) materials (fabri-cated forms) that are produced starting with virgin resinpowders and consolidated forms meeting all the requirementsof Test Method F 648.1.2 This guide does not cover fabricated forms of ultra-highmolecular weight polyethylene which have received only ga
4、splasma, 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 relations
5、hips 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 reproduci
6、bility 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 it
7、s use. 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:2D 638 Test Method for Tensile Properties of PlasticsD 1621 Test Method for
8、Compressive Properties Of RigidCellular PlasticsD 1898 Practice for Sampling of Plastics3D 2765 Test Methods for Determination of Gel Content andSwell Ratio of Crosslinked Ethylene PlasticsD 3418 Test Method for Transition Temperatures of Poly-mers By Differential Scanning CalorimetryE 647 Test Meth
9、od for Measurement of Fatigue CrackGrowth RatesF 619 Practice for Extraction of Medical PlasticsF 648 Specification for Ultra-High-Molecular Weight Poly-ethylene Powder and Fabricated Form for Surgical Im-plantsF 748 Practice for Selecting Generic Biological Test Meth-ods for Materials and DevicesF
10、749 Practice for Evaluating Material Extracts by Intracu-taneous Injection in the RabbitF 756 Practice for Assessment of Hemolytic Properties ofMaterialsF 763 Practice for Short-Term Screening of Implant Mate-rialsF 813 Practice for Direct Contact Cell Culture Evaluation ofMaterials for Medical Devi
11、cesF 895 Test Method for Agar Diffusion Cell Culture Screen-ing for CytotoxicityF 981 Practice for Assessment of Compatibility of Bioma-terials for Surgical Implants with Respect to Effect ofMaterials on Muscle and BoneF 2102 Guide for Evaluating the Extent of Oxidation inUltra-High-Molecular-Weight
12、 Polyethylene FabricatedForms Intended for Surgical ImplantsF 2183 Test Method for Small Punch Testing of Ultra-HighMolecular Weight Polyethylene Used in Surgical ImplantsF 2214 Test Method for In Situ Determination of NetworkParameters of Crosslinked Ultra High Molecular WeightPolyethylene (UHMWPE)
13、1This guide is under the jurisdiction of ASTM Committee F04 on Medical andSurgical Materials and Devices and is the direct responsibility of SubcommitteeF04.11 on Polymeric Materials.Current edition approved July 1, 2006. Published July 2006.2For referenced ASTM standards, visit the ASTM website, ww
14、w.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.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United
15、States.F 2381 Test Method for Evaluating Trans-Vinylene Yield inIrradiated Ultra-High-Molecular-Weight Polyethylene Fab-ricated Forms Intended for Surgical Implants by InfraredSpectroscopy2.2 ISO Standard:ISO 10993 Biological Evaluation of Medical Devices, Parts1-1243. Terminology3.1 Definitions of
16、Terms Specific to This Standard:3.1.1 fabricated formany bulk shape of UHMWPE, fab-ricated from the virgin polymer powder, used during theprocess of fabricating surgical implants prior to crosslinking,packaging, and sterilization.3.1.1.1 extensively crosslinked UHMWPEUHMWPE ma-terial that has been s
17、ubjected to total doses of gamma and/orelectron beam ionizing irradiation greater than 40 kGy for thepurpose of generating crosslinks within the material.3.1.2 ionizing irradiationgamma rays or high energyelectrons irradiation sources.3.1.3 crosslinkingthe process by which ionizing irradia-tion prod
18、uces chemical bonds between two UHMWPE mol-ecules.4. Sampling4.1 Where applicable, the requirements of this guide shallbe determined for each lot of powder and fabricated form bysampling sizes and procedures according to Practice D 1898,oras agreed upon between the purchaser and seller.5. Extensivel
19、y Crosslinked UHMWPE Fabricated FormRequirements5.1 Compositional Requirements:5.1.1 The virgin powder and fabricated forms from whichthe extensively crosslinked material is manufactured shall meetall the requirements of Practice F 648.5.2 Physical Requirements:5.2.1 The manufacture of an extensivel
20、y crosslinked UHM-WPE material may be accomplished many different ways. Assuch, each manufacturer of such material(s) has developed itsown proprietary method(s) for doing so. The end result of thisvariation is that some of the mechanical properties of exten-sively crosslinked materials currently use
21、d for orthopaedicimplant applications exhibit a wide range of values. When thisis coupled with the fact that the limiting value for any specificmechanical property necessary for clinical success is yetunknown, a listing of such data for these materials is currentlyimpractical. It is more useful and
22、practical to describe standardmethods suitable for characterizing these materials.5.2.2 Table 1 lists some tests and methods found useful forcharacterizing extensively crosslinked UHMWPE materials.These tests should be conducted on final product material ormaterials essentially equivalent to the fin
23、al product.6. Biocompatibility6.1 This material has been shown to produce a well char-acterized level of biological response following long termclinical use in laboratory animals. The results of these studiesand the clinical history indicate an acceptable level of biologi-cal response in the applica
24、tions in which the material has beenutilized. When new applications of the material, or modifica-tion to the material or physical forms of the materials are beingcontemplated, the recommendations of ISO 10993, Parts 1-12and Practice F 748 should be considered and testing consideredas described in Pr
25、actices F 619, F 749, F 756, F 763, F 813,and F 981 as well as Test Method F 895.7. Keywords7.1 fabricated forms; powdered form; ultra-high molecularweight polyethylene4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.TABLE 1 Requirements for
26、UHMWPE Fabricated FormsTest Parameter Test Method Test ConditionsTensile Strength, 23C, MPa ASTM D 638 Type IV, 5.08 cm/minUltimateYieldElongation, % ASTM D 638 Type IV, 5.08 cm/minIzod Impact Strength, kJ/m2ASTM F 648, Annex A1Ultimate Load, MPa ASTM F 2183Fatigue Crack Propagation ASTM E 647Compre
27、ssive Modulus, MPa ASTM D 1621Thermal Properties ASTM D 3418Percent CrystallinityMelting Temperature, maxResidual Free Radicals, spins/g ESRSwell Ratio ASTM D 2765 or F 2214Oxidation Index, SOI andOI maxASTM F 2102t-Vinylene Content, TVI ASTM F 2381F2565062APPENDIX(Nonmandatory Information)X1. RATIO
28、NALEX1.1 This guide is intended to describe the minimum set ofrequired test methods that are necessary to fully characterizethe physical, chemical, and mechanical behavior of an irradi-ated, extensively crosslinked UHMWPE material that is in-tended for use as orthopedic or spine implants.X1.2 In 199
29、5, the Food and Drug Administration publisheda 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 expecte
30、d uses for the current ASTMguide is to provide guidance to regulatory bodies and orthope-dic manufacturers by identifying a standardized suite of testmethods for characterizing extensively crosslinked UHMWPEmaterials.X1.3 While it is currently possible to identify which testmethods are necessary for
31、 characterizing extensivelycrosslinked UHMWPE, it remains impractical to assign mini-mum acceptable 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 manufactu
32、rer to develop their own mini-mum dataset for their process of producing extensivelycrosslinked UHMWPE, using the test methods in this guide forprocess validation.X1.4 Although the test methods listed in Table 1 areintended to be the minimum data set necessary for processvalidation with an extensive
33、ly crosslinked UHMWPE material,they are not all intended to be performed routinely duringquality control. It is the responsibility of the manufacturer todevelop a specification for their material, and to identify whichof the test methods listed in Table 1 will be performed routinelyfor quality contr
34、ol purposes.X1.5 Fatigue resistance is a desirable property for exten-sively crosslinked UHMWPE materials. Table 1 lists fatiguecrack propagation tests, in accordance with Test Method E 647,as the reference test method for this attribute. However, certainlinear elastic fracture mechanics principles
35、(for example, theassumption of the plane strain conditions), which underlie themethods of fatigue crack propagation assessment outlined inTest Method E 647, are not strictly applicable to ductilepolymers, such as UHMWPE, regardless of whether or not thematerial has been extensively crosslinked. Ther
36、efore, theinterpretation of fatigue crack propagation 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 dur
37、ing fatigue crackpropagation testing, such as the exponent during the Parisregime and/or DK 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 consid
38、eredto be important for extensively crosslinked materials. 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 s
39、tandardmethod for measuring free radicals in UHMWPE 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 UHMW
40、PEmaterial in Table 1, this guide does not purport to 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
41、 boldface numbers in parentheses refer to the list of references at the end ofthis standard.F2565063REFERENCES(1) Food and Drug Administration, “Data Requirements for Ultra-HighMolecular Weight Polyethylene (UHMWPE) Used in OrthopedicDevices,” Orthopedic Devices Branch, Rockville, MD, March 28,1995.
42、(2) Gencur, S. J., Rimnac, C. M., and Kurtz, S. M., “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 CrackPropa
43、gation Resistance of Highly Crosslinked Polyethylene,” 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
44、,2003, pp. 146-154.(5) Jahan, M. S., Wang, C., Schwartz, G., and Davidson, J.A., “CombinedChemical and Mechanical Effects on Free Radicals in UHMWPEJoints During Implantation,” J Biomed Mater Res, 25, 1991, pp.1005-1017.ASTM International takes no position respecting the validity of any patent right
45、s 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 t
46、ime 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 ASTM International Headquarters. Your comments will
47、 receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM
48、 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).F2565064
