1、BSI Standards PublicationBS ISO 14243-3:2014Implants for surgery Wear oftotal knee-joint prosthesesPart 3: Loading and displacementparameters for wear-testing machines withdisplacement control and correspondingenvironmental conditions for testBS ISO 14243-3:2014 BRITISH STANDARDNational forewordThis
2、 British Standard is the UK implementation of ISO 14243-3:2014.It supersedes BS ISO 14243-3:2004 which is withdrawn.The UK participation in its preparation was entrusted toTechnical Committee CH/150/4, Surgical Implants - Bone and JointReplacements.A list of organizations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 committ
3、ee can beobtained on request 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 73554 7ICS 11.040.40Com
4、pliance with a British Standard 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 14243-3:2014 ISO 2014Implants for surgery
5、Wear of total knee-joint prostheses Part 3: Loading and displacement parameters for wear-testing machines with displacement control and corresponding environmental conditions for testImplants chirurgicaux Usure des prothses totales de larticulation du genou Partie 3: Paramtres de charge et de dplace
6、ment pour machines dessai dusure avec contrle de dplacement et conditions environnementales correspondantes dessaiINTERNATIONAL STANDARDISO14243-3Second edition2014-11-01Reference numberISO 14243-3:2014(E)BS ISO 14243-3:2014ISO 14243-3:2014(E)ii ISO 2014 All rights reservedCOPYRIGHT PROTECTED DOCUME
7、NT ISO 2014All rights reserved. Unless otherwise specified, no part of this publication 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 b
8、e requested from either ISO at the address below or ISOs member body in the country 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 14243-3:2014ISO 14243-3:2014(E) IS
9、O 2014 All rights reserved iiiContents PageForeword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 45 Specimens, lubricants, and sample size . 55.1 Fluid test medium 55.2 Test specimen . 55.3 Control specimen 55.4 Number of test specimens . 56 Apparatus . 67 Procedure. 7
10、7.1 Initial Measurements . 78 Test report 129 Disposal of test specimen .13Annex A (informative) Details of load and displacement parameters for the test cycle described in Figures 2 to 5 14BS ISO 14243-3:2014ISO 14243-3:2014(E)ForewordISO (the International Organization for Standardization) is a wo
11、rldwide 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 committee has been established has the right to be represented o
12、n 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 electrotechnical standardization.The procedures used to develop this
13、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 in accordance with the editorial rules of the ISO/IEC Dire
14、ctives, Part 2 (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. Details of any patent rights identified during the developmen
15、t of the document will be in the Introduction and/or on the ISO list of patent declarations received (www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific t
16、erms 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 information.The committee responsible for this document is ISO/TC 150, Implants for surgery,
17、 Subcommittee SC 4, Bone and joint replacement.This second edition cancels and replaces the first edition (ISO 14243-3:2004) which has been technically revised. It incorporates also the Technical corrigendum ISO 14243-3:2004/Cor 1: 2006.ISO 14243 consists of the following parts, under the general ti
18、tle Implants for surgery Wear of total knee-joint prostheses: Part 1: Loading and displacement parameters for wear-testing machines with load control and corresponding environmental conditions for test Part 2: Methods of measurement Part 3: Loading and displacement parameters for wear-testing machin
19、es with displacement control and corresponding environmental conditions for testiv ISO 2014 All rights reservedBS ISO 14243-3:2014INTERNATIONAL STANDARD ISO 14243-3:2014(E)Implants for surgery Wear of total knee-joint prostheses Part 3: Loading and displacement parameters for wear-testing machines w
20、ith displacement control and corresponding environmental conditions for test1 ScopeThis part of ISO 14243 describes a test method that specifies flexion/extension relative angular movement between articulating components, the pattern of the applied force, speed and duration of testing, sample config
21、uration and test environment to be used for the wear testing of total knee-joint prostheses in wear-testing machines having axial load control, flexion/extension angular motion control, AP displacement control and tibial rotation control.The kinematics of this part of ISO 14243 may not be applicable
22、 to knee designs with a high degree of constraint, which could result in damage to the articulating components in the early stages of the test that would not be representative of clinical service.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this d
23、ocument 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 7207-1, Implants for surgery Components for partial and total knee joint prostheses Pa
24、rt 1: Classification, definitions and designation of dimensionsISO 14243-2:2009, Implants for surgery Wear of total knee-joint prostheses Part 2: Methods of measurement3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 14243-1 and the following apply.3.1
25、Anterior/Posterior (AP) displacementoffset between the femoral component and the tibial component, measured in a direction which is perpendicular to both the force and flexion/extension axesNote 1 to entry: The AP displacement is considered to be zero when the total knee-joint prosthesis is in the r
26、eference position (3.7) and is considered to be positive when the tibial component is anterior to its position with the total knee-joint prosthesis in the reference position.3.2AP forceshear force applied by the tibial on the femoral component along a line of action which is perpendicular to both th
27、e tibial axis and the flexion/extension axis and which passes through the axial force axis.Note 1 to entry: The AP force is considered to be positive when it acts in a posterior-to-anterior direction. ISO 2014 All rights reserved 1BS ISO 14243-3:2014ISO 14243-3:2014(E)Key1 flexion (of femoral compon
28、ent)2 tibial rotation3 AP displacement by the tibial component4 axial forceFigure 1 Sign convention for the forces and motions, shown for a left total knee replacement system3.3axial forceforce applied by the tibial component of the knee-joint prosthesis on the femoral component in a direction paral
29、lel to the tibial axisNote 1 to entry: It is considered to be positive when it acts in an inferior-to-superior direction. (See Figures 1 and 2).3.4axial force axisline of action of the axial force taken to pass through a point on the tibial component of the knee-joint prosthesis which is offset by 0
30、,07 w 0,01 w in the medial direction from the tibial axis, where w is the overall width of the tibial component, measured in accordance with ISO 7207-1Note 1 to entry: The value of 0,07 w offset equals 5 mm offset for a tibial component of average width, i.e. 74 mm. See Figure 2.3.5flexion/extension
31、 axisnominal axis of rotation of the femoral component relative to the tibial componentNote 1 to entry: For condylar and meniscal knees, the flexion/extension axis can be estimated by considering the condyles of the femoral component in contact with an imaginary plane perpendicular to the tibial axi
32、s when the femoral component is at 30 and 60 of flexion, and then visualizing four lines (contact normals) perpendicular to the imaginary plane running through the points where the two femoral condyles would contact the imaginary plane at each of these flexion angles. The flexion/extension axis is t
33、hen the line that would intersect all four of the contact normals.Note 2 to entry: The axis of rotation of the femoral component in the test will not exactly match the theoretical flexion/extension axis. The coincidence of the flexion/extension axis and the axis of rotation of the test machine shoul
34、d be as close as possible within reasonable laboratory practice.2 ISO 2014 All rights reservedBS ISO 14243-3:2014ISO 14243-3:2014(E)3.6load and displacement control wear-testing machinewear-testing machine having axial load control, flexion/extension angular motion control, AP displacement control a
35、nd tibial rotation control as its control parametersKey1 axial force axis2 tibial axis3 0,07w offset4 holder of tibial component5 cement mounting for tibial component6 axial force applied through free-turning pivot(s)7 forceFigure 2 Test specimen configuration3.7reference positionangular and linear
36、alignment of the tibial component relative to the femoral component which gives static equilibrium of the tibial component when it is loaded against the femoral component by a positive axial force applied along the axial force axis, with the most distal points on the femoral bearing surface resting
37、on the lowest points on the tibial bearing surfaceNote 1 to entry: The reference position is equivalent to the position of 0 flexion (i.e. full extension) in vivo.Note 2 to entry: For the purpose of determining the reference position, the effect of friction between the tibial and femoral components
38、is ignored. ISO 2014 All rights reserved 3BS ISO 14243-3:2014ISO 14243-3:2014(E)Note 3 to entry: The reference position can be determined by geometrical calculations based on the three-dimensional form of the tibial and femoral surfaces. For the purpose of these calculations, the form of the tibial
39、and femoral surfaces can be taken either from design data or from coordinate measurements of an unworn total knee-joint prosthesis.Note 4 to entry: In a moderately constrained or flat design of tibial component, and/or installation of the tibial component with a large posterior slope (see 7.4), the
40、lowest points on the tibial bearing surface may span a large (flat) range of anterior-posterior positions, or be the most posterior edge of the tibial component (no dish effect). In such a situation, the above definition of reference position cannot apply. In such situations, the prosthesis manufact
41、urer is consulted to decide what neutral position should be forced/set, and this should be noted in detail in the test report.3.8tibial axisnominal longitudinal axis of the tibia, corresponding to the central axis of the medullary cavity of the proximal tibia3.9tibial rotationrotation of the tibial
42、component of the knee-joint prosthesis about an axis parallel to the tibial axisNote 1 to entry: The rotation is considered to be zero when the total knee-joint prosthesis is in the reference position (3.7). For a right-sided total knee-joint prosthesis, the tibial rotation is positive when a view f
43、rom a superior position onto the tibial component shows the tibial component rotated anti-clockwise from its position with the total knee-joint prosthesis in the reference position (3.7).3.10tibial rotation torquetorque applied by the tibial component on the femoral component of the total knee-joint
44、 prosthesis about an axis parallel to the tibial axisNote 1 to entry: When seen from a position superior to the tibial component, the axial torque is positive when it acts clockwise on a left-sided total knee-joint prosthesis and positive when it acts anti-clockwise on a right-sided total knee-joint
45、 prosthesis.3.11passive soak control specimensamples of the same polymer articulating components used in wear test will be immersed in the same fluid test medium at the same temperature for the same time as the wear test duration3.12loaded control specimensample(s) of the same polymer articulating c
46、omponents used in wear test will be immersed in the same fluid test medium at the same temperature for the same time with the same time varying axial force as the wear test, but without any articulating motions3.13tibial base platecomponent of a modular tibial knee in contact with the tibia that sup
47、ports the tibial polyethylene bearing component4 PrincipleThe total knee-joint prosthesis is mounted in an apparatus that applies cyclic variations of flexion/extension angle, tibial rotation angle, AP displacement and axial force to the interface between tibial and femoral components, simulating no
48、rmal human walking. The tibial component moves relative to the femoral component under the influence of the applied flexion/extension rotation, tibial rotation, AP displacement, and axial forces. The applied contact force/displacement actions are axial force, flexion/extension rotation, AP displacem
49、ent and tibial rotation. All the applied force/displacement actions follow a specified cyclic variation, with a fixed relationship between the phases of the actions.4 ISO 2014 All rights reservedBS ISO 14243-3:2014ISO 14243-3:2014(E)The contacting surfaces of the femoral and tibial components are immersed in a fluid test medium simulating human synovial fluid. A control specimen is subjected to the fluid medium and optionally to the same time-varying axial force to determine the creep of the test specimen and/or the
