1、Designation: F 1781 03Standard Specification forElastomeric Flexible Hinge Finger Total Joint Implants1This standard is issued under the fixed designation F 1781; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. 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 specification covers elastomeric flexible hingefinger total joint implants, used with and without metalgrommets in the r
3、econstruction of the metacarpophalangeal(MCP) and proximal interphalangeal (PIP) joints.1.2 This specification excludes those implants that do nothave an across-the-joint elastomeric linkage. The specificationis limited to implants made from one material in a singleone-step molding procedure.1.3 The
4、 values stated in SI units are to be regarded asstandard. The inch-pound units given in parentheses are forinformation only.2. Referenced Documents2.1 ASTM Standards:2D 412 Test Methods for Vulcanized Rubber and Thermo-plastic Rubbers and Thermoplastic ElastomersTensionD 624 Test Method for Tear Str
5、ength of ConventionalVulcanized Rubber and Thermoplastic ElastomersD 813 Test Method for Rubber-DeteriorationCrackGrowthD 1052 Test Method for Measuring Rubber DeteriorationCut Growth Using Ross Flexing ApparatusD 2240 Test Method for Rubber PropertyDurometerHardnessF 67 Specification for Unalloyed
6、Titanium for SurgicalImplant Applications (UNS R50250, R50400, R50550,R50700)F 86 Practice for Surface Preparation and Marking of Me-tallic Surgical ImplantsF 601 Practice for Fluorescent Penetrant Inspection of Me-tallic Surgical ImplantsF 748 Practice for Selecting Generic Biological Test Meth-ods
7、 for Materials and DevicesF 981 Practice for Assessment of Compatibility of Bioma-terials for Surgical Implants with Respect to Effect ofMaterials on Muscle and BoneF 983 Practice for Permanent Marking of Orthopaedic Im-plant ComponentsF 2038 Guide for Silicone Elastomers, Gels and FoamsUsed in Medi
8、cal Applications, Part IFormulations andUncured MaterialsF 2042 Guide for Silicone Elastomers, Gels and FoamsUsed in Medical Applications, Part IICrosslinking andFabrication2.2 Government Standards:21 CFR Part 820 Good Manufacturing Practices for Medi-cal Devices3MIL STD 177A Rubber Products, Terms
9、for Visible De-fects32.3 Other Standard:EN 30993-1 Biological Evaluations of Medical DevicesPart 1: Guidance on Selection of Tests43. Significance and Use3.1 The prostheses described in this specification are in-tended for use in the proximal interphalangeal (PIP) andmetacarpophalangeal (MCP) joints
10、.4. Classification4.1 ConstrainedA constrained joint prosthesis is used forjoint replacement and prevents dislocation of the prosthesis inmore than one anatomical plane and consists of either a single,flexible, across-the-joint component, or more than one compo-nent linked together or affixed.5. Mat
11、erials and Manufacture5.1 Proper material selection is necessary, but insufficient toensure suitable function of a device. All devices conforming tothis specification shall be fabricated from materials withadequate mechanical strength, durability and biocompatibility.5.2 All elastomeric components s
12、hall conform to GuidesF 2038 and F 2042. Test and evaluation parameters that couldbe considered for the elastomeric implant materials are GuidesF 2038 and F 2042, Practice F 748, Test Methods D 813,1This specification is under the jurisdiction of ASTM Committee F04 onMedical and Surgical Material an
13、d Devices and is the direct responsibility ofSubcommittee F04.22 on Arthroplasty.Current edition approved Nov. 1, 2003. Published December 2003. Originallyapproved in 1997. Last previous edition approved in 1997 as F 1781 97.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcon
14、tact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Superintendent of Documents, U.S. Government PrintingOffice, Washington, DC 20402.4Available from American National Stan
15、dards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D 1052, D 2240, D 412 and D 624. Before implants can bemanufactured from other materials, manufacturers must com-ply
16、 with 5.4.5.3 Titanium used as a material of construction for metalgrommets shall conform to Specification F 67. Metal grommetsmust match the shape of the implant and not interfere with theflexible hinge implant function.5.4 BiocompatibilityFlexible hinge implants shall bemanufactured from the mater
17、ials listed in 5.2 and 5.3. Beforeimplants can be manufactured from other materials, theirbiocompatibility must be demonstrated by producing an ac-ceptable response after testing in accordance with PracticesF 748 and F 981, and others (see EN 30993-1) as needed.5.5 When appropriate for metallic grom
18、mets, fluorescentpenetrant inspection shall be performed in accordance withPractice F 601.5.6 Design and manufacture will follow 21 CFR Part 820.6. Performance Requirements6.1 Fatigue TestingThe fatigue characteristics of materialfrom which the elastomeric components are fabricated must beevaluated
19、according to Test Method D 813. Any test should bedesigned to measure fatigue rate (for example, crack growthlength) as a function of a million(s) cycles.6.2 Range of Motion of the Device Before ImplantationThe implant shall be evaluated to determine the maximumflexion and extension possible before
20、subluxation occurs or themotion is arrested by the implant (elastomer-to-elastomercontact within the hinge). These results shall be reported in theproduct labeling.6.3 Guidelines for in vitro Laboratory TestingNo ASTMstandards for testing finger implants have been developed.Laboratory testing that s
21、imulates the conditions of use, by ajoint function simulator, is desirable to compare materials anddesigns and to provide an indication of clinical performance.Implant testing shall be done in keeping with the implantsintended function, that is, implants intended to partially stabi-lize or stabilize
22、 a joint shall be subjected to the maximumdestabilizing force or motion, or both, anticipated in clinicalapplication during flexural testing.6.4 DurometerThe hardness of elastomeric componentsshall be measured according to Test Method D 2240.6.5 The mechanical properties (such as tensile strength,pe
23、rcentage elongation, modulus, and tear strength) of theelastomeric materials used in components shall be determinedaccording to Test Methods D 412 and D 624.7. Dimensions7.1 Dimensions of finger and joint replacement componentsshall be reported in labeling (see Figs. 1 and 2):7.1.1 Distal stem lengt
24、h,7.1.2 Proximal stem length,7.1.3 Hinge width in medial/lateral plane,7.1.4 Hinge height in dorsal/palmar plane,7.1.5 Distal stem width,7.1.6 Proximal stem width, and7.1.7 Distal-proximal hinge width.7.2 Dimensions of finger implant with metal grommets shallbe reported in labeling (see Fig. 3):7.2.
25、1 Distal stem length,7.2.2 Proximal stem length,7.2.3 Distal grommet length,7.2.4 Proximal grommet length, and7.2.5 Hinge height in dorsal/palmar plane.8. Finish and Marking8.1 Items conforming to this specification shall be finishedand marked in accordance with Practice F 86 and F 983, whereapplica
26、ble.8.2 Polymeric Surface FinishPolymeric Surface Finishshall conform to manufacturers documented standards con-cerning roughness, knit lines, void, bubbles, mold fill, color,inclusions, and dimensions, when applicable. Descriptions ofthese terms can be located in MIL STD 177A.9. Labeling and Packag
27、ing9.1 The maximum range of motion values as determined by6.2 shall be included in the product labeling. The minimumlimits for the mechanical properties of the elastomeric materi-al(s) used in components shall be included in theproductlabeling.9.2 The dimensions shall be included in the product labe
28、l-ing.FIG. 1 Dimensions of Finger and Joint Replacement ComponentsF17810329.3 The material(s) used for the implant shall be specified inthe package labeling.9.4 The site, orientation (if any), and catalog number ifspace permits should be present on the component or within thelabeling.NOTE 1If space
29、permits the manufacturers trademark must appearlegibly on each of the components. If space does not permit such, theinformation must be written in the labeling.10. Keywords10.1 elastomer; finger; implantFIG. 2 Dimensions of Finger and Joint Replacement ComponentsFIG. 3 Dimensions of Finger ImplantF1
30、781033APPENDIXES(Nonmandatory Information)X1. RATIONALEX1.1 The objective of this specification is the provision ofguidelines for the physical characteristics of the componentsfor elastomeric total finger joint replacement. Total finger jointreplacement parts are intended for use in a patient who is
31、skeletally mature under conditions of imposed dynamic loads,in a corrosive environment and subject to motion at the bearingsurfaces, (grommet-hinge interface, hinge-bone interface, orgrommet-bone interface). Laboratory tests for finger jointswhich accurately simulate imposed loads, appropriate range
32、sof motion, aggressive electrolytes, and the complex constitu-ents of body fluids have not been developed. Long termprojections of satisfactory performance over many decades canbe suggested but not accurately predicted using availablescreening procedures. This document identifies those factorsfelt t
33、o be important to assure a satisfactory prosthetic life. It isrecognized that failure of an arthroplasty can occur, even whilethe components are intact. This is due to the composite natureof the arthroplasty procedure, which includes the implants, thesurgical procedure, post-operative care, patient
34、use, and thephysiological environment.X1.1.1 This specification excludes those implants that donot have an across-the-joint elastomeric linkage and is limitedto implants made from one material in a single, one-stepmolding procedure. It also excludes implants which utilizebone cement as affixation me
35、thod, and implants defined as“partially constrained” or “non-constrained.”X1.1.2 Under applicable documents and materials, the listreflects the current state of the art. It is recognized that shouldmaterials not now included appear and be proved acceptable,they shall be inserted into this standard d
36、uring the process ofrevision.X1.2 Performance ConsiderationsComponent perfor-mance can be predicted only indirectly at this stage by referringto fatigue performance, range of motion, and other parameters.Reference to parameters applicable to materials may or maynot adequately describe a device made
37、from the materials. Inthe future as new materials are developed, other materialtesting methods not described in the standard, such as TestMethod D 1052, may be considered for screening possiblematerials for flexible hinge implants. If these materials aresuitable, this standard will be revised to inc
38、lude them aspotential candidate materials for total flexible finger implants.In a period of transition from materials specification standardsto device performance standards, both methods of descriptionmay be appropriate.X1.2.1 Component performance shall be considered withregard to patient anatomy.
39、It is well recognized that physicalstresses resulting from events or activities out of the ordinaryrange, as in accidents or especially vigorous sports, predictablyexceed allowable stresses in levels in any component design.When mal-alignment, or dislocation/subluxation occurs in aMCP or PIP joint r
40、econstructed with a constrained flexiblehinge implant, the forces borne by the implant may causepremature destruction. It is also recognized that other forms ofarthroplasty failure are known to occur, related primarily topatient factors, such as osteoporosis, aggressive rheumatoiddisease misuse, and
41、 others.X1.2.2 Specific criteria need to be established in assessingthe biocompatibility of finger implants made of new materials.Practice F 748 will need to be used to determine whichadditional biocompatibility tests are required.X1.2.3 In the course of evaluating new materials, it isrecommended th
42、at if the material is used in an application thatcauses small particle formation from abrasion or normal wearprocesses that the biocompatibility of those particles be deter-mined in addition to the bulk material.X1.3 DimensionsThe methods of dimensional measure-ment must conform with the industry pr
43、actice and wheneverpossible, on an international practice.X1.4 Finish and MarkingsDimensions and tolerances areas described by manufacturers standards. Material composi-tion can be determined by referring to the manufacturersinformation, instead of marking the material on each implant.X2. ADDITIONAL
44、 PUBLICATIONSFrisch, E. E., “High Performance Medical Grade SiliconeElastomer,” Advances in Biomaterials 1, Stuart M. Lee ed.,Technomic Publishing Co., Inc., Lancaster, PA, 1987, pp.143156.Peimer, C. A., Meidige, J., Eckert, B. S., Wright, J. R.,Howard, C. S., “Reactive Synovitis After Silicone Arth
45、ro-plasty,” Journal of Hand Surgery, 11, 1986, pp. 624638.Savory, K. M., Hutchinson, D. T., Bloebaum, R., “AMaterials Testing Protocol for Small Joint Prostheses,” Trans-actions for Society for Biomaterials, 17:244, 1994.Schneider, L. H., M.D., and Kirschenbaum, D., M.D.,“Arthroplasty at the Metacar
46、pophalangeal Joints,” OperativeTechniques in Orthopaedics, 6: 1996, pp. 110116.F1781034Swanson, A. B., Swanson, G. de Groot, Frisch, E. E.,“Flexible (Silicone) Implant Arthroplasty in the Small JointExtremities: Concepts, Physical and Biological Consider-ations, Experimental and Clinical Results,” B
47、iomaterials inReconstructive Surgery, L. R. Rubin, M.D. ed., C. V. MosbyCompany St. Louis, MO, Chapter 40, 1983.Wilson, Y. G., Sykes, P. J., and Niranjan, N. S., “Long-TermFollow-Up of Swansons Silastic Arthroplasty of the Metacar-pophalangeal Joints in Rheumatoid Arthritis,” Journal of HandSurgery,
48、 18B: 1993, pp. 8191.ASTM International takes no position respecting the validity 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 infringemen
49、t 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 ASTM International Headquarters. Your comments will 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 h
