1、BSI Standards PublicationBS ISO 14242-1:2014Implants for surgery Wear oftotal hip-joint prosthesesPart 1: Loading and displacementparameters for wear-testing machines andcorresponding environmental conditions fortestBS ISO 14242-1:2014 BRITISH STANDARDNational forewordThis British Standard is the UK
2、 implementation of ISO 14242-1:2014.It supersedes BS ISO 14242-1:2002 which is withdrawn.The UK participation in its preparation was entrusted toTechnical Committee CH/150/4, Surgical Implants - Bone and JointReplacements.A list of organizations represented on this committee can beobtained on reques
3、t to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2014. Published by BSI StandardsLimited 2014ISBN 978 0 580 82475 3ICS 11.040.40Compliance with a British Stan
4、dard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 October 2014.Amendments issued since publicationDate Text affectedBS ISO 14242-1:2014 ISO 2014Implants for surgery Wear of total hip-joint pro
5、stheses Part 1: Loading and displacement parameters for wear-testing machines and corresponding environmental conditions for testImplants chirurgicaux Usure des prothses totales de larticulation de la hanche Partie 1: Paramtres de charge et de dplacement pour machines dessai dusure et conditions env
6、ironnementales correspondantes dessaiINTERNATIONAL STANDARDISO14242-1Third edition2014-10-15Reference numberISO 14242-1:2014(E)BS ISO 14242-1:2014ISO 14242-1:2014(E)ii ISO 2014 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2014All rights reserved. Unless otherwise specified, no part of this pu
7、blication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the co
8、untry of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 14242-1:2014ISO 14242-1:2014(E)Contents PageForeword iv1 Scope . 12 Normative references 13 Terms and definition
9、s . 14 Principle 25 Test and control specimens and test fluid 26 Apparatus . 27 Procedure. 68 Test report . 79 Disposal of test specimen 8Annex A (informative) Generation of rotation and load curves by formulae . 9 ISO 2014 All rights reserved iiiBS ISO 14242-1:2014ISO 14242-1:2014(E)ForewordISO (th
10、e International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committ
11、ee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechn
12、ical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted i
13、n accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
14、 Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute
15、 an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committe
16、e responsible for this document is ISO/TC 150, Implants for surgery, Subcommittee SC 4, Bone and joint replacements.This third edition cancels and replaces the second edition (ISO 14242-1:2012), which has been technically revised.ISO 14242 consists of the following parts, under the general title Imp
17、lants for surgery Wear of total hip-joint prostheses: Part 1: Loading and displacement parameters for wear-testing machines and corresponding environmental conditions for test Part 2: Methods of measurement Part 3: Loading and displacement parameters for orbital bearing type wear testing machines an
18、d corresponding environmental conditions for testiv ISO 2014 All rights reservedBS ISO 14242-1:2014Implants for surgery Wear of total hip-joint prostheses Part 1: Loading and displacement parameters for wear-testing machines and corresponding environmental conditions for test1 ScopeThis part of ISO
19、14242 specifies the relative angular movement between articulating components, the pattern of the applied force, the speed and duration of testing, the sample configuration, and the test environment to be used for the wear testing of total hip-joint prostheses.2 Normative referencesThe following doc
20、uments, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 3696, Water for analy
21、tical laboratory use Specification and test methodsISO 7206-1, Implants for surgery Partial and total hip joint prostheses Part 1: Classification and designation of dimensionsISO 14242-2, Implants for surgery Wear of total hip-joint prostheses Part 2: Methods of measurement3 Terms and definitionsFor
22、 the purposes of this document, the terms and definitions given in ISO 7206-1 and the following apply.3.1abduction/adductionangular movement shown in Figure 1 a)3.2flexion/extensionangular movement shown in Figure 1 b)3.3inward/outward rotationangular movement shown in Figure 1 c)3.4polar axisaxis o
23、f the acetabular component which intersects the centre of the spherical articulating surface and is perpendicular to the plane of the flange or, if no flange is present, perpendicular to the plane of the entry diameterINTERNATIONAL STANDARD ISO 14242-1:2014(E) ISO 2014 All rights reserved 1BS ISO 14
24、242-1:2014ISO 14242-1:2014(E)4 PrincipleThe femoral and acetabular components of a test specimen are placed in position in their normal configuration. The test apparatus transmits a specified time-varying force between the components, together with specified relative angular displacements. A control
25、 specimen, if polymers are the object of investigation, is subjected to the same time-varying force to determine the creep of the test specimen and/or the amount of mass change due to fluid transfer. The test takes place in a controlled environment simulating physiological conditions.5 Test and cont
26、rol specimens and test fluid5.1 Fluid test medium, calf serum diluted with deionized water in accordance with ISO 3696.The fluid test medium shall be filtered through a 2 m filter and have a protein mass concentration of 30 g/l 2 g/l. To minimize microbial contamination, the fluid test medium shall
27、be stored frozen until required for testing. An antimicrobial reagent (such as sodium azide) can be added.WARNING Antimicrobial reagents can be potentially hazardous.Routine monitoring of the pH of the fluid test medium can be undertaken. If so, the values and the relevant number of load cycles shou
28、ld be included in the test report see Clause 8 item f) 6).The recommended protein concentration of 30 g/l has been shown to result in reasonably physiological wear mechanisms and wear rates with a variety of materials in a variety of hip simulators, and is stipulated here in the interest of facilita
29、ting comparison of results among laboratories implementing this part of ISO 14242. Nevertheless, the user should routinely validate the results obtained in a hip simulator by direct comparison with implants of the same design and bearing materials that have been worn in vivo. If substantial differen
30、ces are noted, the user might wish to use a higher or lower concentration of protein in the test lubricant, if it can be documented that this provides a closer agreement with in the vivo wear mechanisms and wear rates.NOTE The use of a fluid test medium of non-biological origin can be considered whe
31、n performance requirements relating to this test method are being decided.5.2 Test specimen, femoral head and acetabular components.The acetabular component shall have the articulating surface attached by its normal immediate backing (for example bone cement or a machined replica of the inner surfac
32、e of the backing) unless this is impractical due to physical features of the implant system. If the component forming the articulating surface is fixed to the backing by a rim/snap-fit system, the machined replica shall provide the same fixation conditions.If it is not practical to use the normal ba
33、cking or cement fixation due to physical features of the implant system, the support system for the acetabular component should reproduce the design features and conditions intended for clinical use but should allow removal of the component for measurement of wear without destruction.The features co
34、nnecting the acetabular component to the test rig shall prevent any movement and should not apply forces in restricted regions that might develop localized points of high stress.5.3 Control specimen, identical to test specimen.6 Apparatus6.1 Testing machine, capable of producing the angular displace
35、ments specified in Figures 1 and 2 in association with the corresponding forces specified in Figures 1 and 3, and operating at a frequency of 1 Hz 0,1 Hz.2 ISO 2014 All rights reservedBS ISO 14242-1:2014ISO 14242-1:2014(E)6.2 Means of mounting and enclosing the test specimen, using a corrosion-resis
36、tant material, capable of holding femoral and acetabular components using attachment methods comparable to the intended anatomical fixation. An enclosure shall be provided which is capable of isolating the test specimen to prevent third-body contamination from the test machine and the atmosphere.6.3
37、 Means of aligning and positioning the femoral component of the test specimen in the inferior position, so that its axis is situated at the centre of the axes of rotation of the test machine and so that the same position and orientation can be reproduced following removal for measurement or cleaning
38、, if required.6.4 Means of aligning and positioning the acetabular component of the test specimen so that its axis is situated at the centre of the axes of rotation of the test machine and so that the same position and orientation can be reproduced following removal for measurement.NOTE It is advisa
39、ble that care be taken during start-up and operation of the test so that air does not accumulate in the acetabular cup and deprive portions of the articulating surfaces of lubricant.6.5 Motion control system, capable of generating the angular movements of the femoral component given in Figures 1 and
40、 2 with an accuracy of 3 at the maxima and minima of the motion and 1 % of the cycle time for phasing. The angles are specified to produce three-dimensional angular movements. The sequence of the angular transformation is: abduction/adduction, followed by flexion/extension, followed by internal/exte
41、rnal rotation. Other sequences should be documented in the test report.6.6 Force control system, capable of generating a force whose direction is shown in Figure 1 and which varies as shown in Figure 3, and maintaining the magnitude of the maxima and minima of this force cycle to a tolerance of 3 %
42、of the maximum force value for the cycle and 3 % of the cycle time for phasing.6.7 Lubrication system, capable of maintaining the contact surfaces immersed in the fluid test medium.NOTE It is advisable to use sealed enclosures in order to prevent evaporation.6.8 Temperature control system, capable o
43、f maintaining the temperature of the fluid test medium at 37 C 2 C.The test shall be closely monitored for evidence of excessive temperatures and corrective measures taken if needed. These can include stopping the test periodically to allow the bearing and lubricant to cool, and cooling the lubrican
44、t bath by, for example, circulating it through a cooling apparatus.6.9 Control station(s), capable of applying the loading regime shown in Figures 1 and 3 without the angular displacements shown in Figures 1 and 2, and incorporating the provisions of 6.2, 6.3, 6.4, 6.6, 6.7, and 6.8. ISO 2014 All ri
45、ghts reserved 3BS ISO 14242-1:2014ISO 14242-1:2014(E)a) Abduction/adduction b) Flexion/extensionc) Inward/outward rotationd) Orientation of acetabular component and femoral component in mid-position relative to the load lineKey1 load axis2 flexion/extension angle3 abduction/adduction angle4 inward/o
46、utward rotation angle5 polar axis of acetabular componentL inclination of the polar axis of the acetabular component to the load line4 ISO 2014 All rights reservedBS ISO 14242-1:2014ISO 14242-1:2014(E)N inclination of the face of the acetabular component equal to 60 3, or as specified by the manufac
47、turerP inclination of stem axis to load line in mid-position of abduction/adduction rangeNOTE Angles N, L, and P are specified in 7.3 and 7.4.Figure 1 Angular movement of femoral component and orientation of components relative to the load lineKeyX time, as a percentage of cycle timeY angle of femor
48、al movement, in degreesAB AbductionAD AdductionE ExtensionF FlexionIR Inward rotationOR Outward rotationFigure 2 Variation with time of angular movement to be applied to the femoral test specimen ISO 2014 All rights reserved 5BS ISO 14242-1:2014ISO 14242-1:2014(E)Time, % of cycle (1 %) 0 21 50 62 10
49、0Angle of flexion (+) or extension () 3 25 -18 25Angle of adduction (+) or abduction () 3 3 7 -4 3Angle of inward (+) or outward () rotation 3 -10 2 -10KeyX time, as a percentage of cycle timeY load in kNFigure 3 Variation with time of the force to be applied along the loading axisTime, % of cycle (3 %) 0 12 32 50 62 100Applied force, kN (90 N) 0,3 3,0 1,5 3,0 0,3 0,37 Procedure7.1 Make any initial measurements required to determine the subsequent amount of wear and/or creep
