BS ISO 14243-1-2009 Implants for surgery - Wear of total knee-joint prostheses - Loading and displacement parameters for wear-testing machines with load control and corresponding e.pdf

1、BS ISO14243-1:2009ICS 11.040.40; 19.060NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDImplants for surgery Wear of total knee-jointprosthesesPart 1: Loading and displacementparameters for wear-testing machineswith load control and correspondingenvironmental con

2、ditions for testThis British Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 31 December2009 BSI 2009ISBN 978 0 580 61307 4Amendments/corrigenda issued since publicationDate CommentsBS ISO 14243-1:2009National forewordThis British Standard is the UK implement

3、ation of ISO 14243-1:2009. Itsupersedes BS ISO 14243-1:2002 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CH/150/4, Surgical Implants - Bone and Joint Replacements.A list of organizations represented on this committee can be obtained onrequest to its

4、secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.BS ISO 14243-1:2009Reference numberISO 14243-1:2009(E)ISO 2009INTERNATIO

5、NAL STANDARD ISO14243-1Second edition2009-11-15Implants 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 Implants chirurgicaux Usure des prothses totales de lart

6、iculation du genou Partie 1: Paramtres de charge et de dplacement pour machines dessai dusure avec contrle de la charge et conditions environnementales correspondantes dessai BS ISO 14243-1:2009ISO 14243-1:2009(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes

7、 licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobes licensing policy. T

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9、as been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. COPYRIGHT PROTECTED DOCUMENT ISO 2009 All rights reserved. Unless otherwise specified, no pa

10、rt of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale

11、56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2009 All rights reservedBS ISO 14243-1:2009ISO 14243-1:2009(E) ISO 2009 All rights reserved iiiContents Page Foreword iv 1 Scope1 2 Normative references1 3 Terms

12、and definitions .1 4 Principle4 5 Specimens and lubricants4 6 Apparatus.5 7 Procedure.9 8 Test report10 9 Disposal of test specimen 11 Annex A (informative) Details of load and displacement parameters for the test cycle described in Figures 3 and 4 12 BS ISO 14243-1:2009ISO 14243-1:2009(E) iv ISO 20

13、09 All rights reservedForeword ISO (the 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

14、 subject for which a technical committee 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 Commissio

15、n (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical co

16、mmittees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall no

17、t be held responsible for identifying any or all such patent rights. ISO 14243-1 was prepared by Technical Committee ISO/TC 150, Implants for surgery, Subcommittee SC 4, Bone and joint replacements. This second edition cancels and replaces the first edition (ISO 14243-1:2002), which has been technic

18、ally revised. ISO 14243 consists of the following parts, under the general title 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 me

19、asurement Part 3: Loading and displacement parameters for wear-testing machines with displacement control and corresponding environmental conditions for test BS ISO 14243-1:2009INTERNATIONAL STANDARD ISO 14243-1:2009(E) ISO 2009 All rights reserved 1Implants for surgery Wear of total knee-joint pros

20、theses Part 1: Loading and displacement parameters for wear-testing machines with load control and corresponding environmental conditions for test 1 Scope This part of ISO 14243 specifies the flexion/extension relative angular movement between articulating components, the pattern of the applied forc

21、e, speed and duration of testing, sample configuration and test environment to be used for the wear testing of total knee-joint prostheses in wear-testing machines with load control. 2 Normative references The following referenced documents are indispensable for the application of this document. For

22、 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 Part 1: Classification, definitions and designation of

23、dimensions ISO 14243-2, Implants for surgery Wear of total knee-joint prostheses Part 2: Methods of measurement 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 AP displacement offset of the axial force axis from the flexion/extension axis mea

24、sured in a direction that is perpendicular to both of these axes NOTE 1 AP is an abbreviation for anterior posterior. NOTE 2 The displacement is considered to be zero when the total knee-joint prosthesis is in the reference position (3.7) and is considered to be positive when the axial force axis is

25、 anterior to its position with the total knee-joint prosthesis in the reference position (3.7). See Figure 1. 3.2 AP force force applied to the tibial component along a line of action that is perpendicular to both the tibial axis and the flexion/extension axis and which passes through the axial forc

26、e axis NOTE The force is considered to be positive when it acts from a posterior to an anterior direction on the tibial component. See Figure 1. BS ISO 14243-1:2009ISO 14243-1:2009(E) 2 ISO 2009 All rights reservedKey 1 flexion (of femoral component) 2 tibial rotation, tibial rotation torque 3 AP di

27、splacement by the tibial component, AP force on the tibial component 4 axial force Figure 1 Sign convention for the forces, torques and motions, shown for a left total knee replacement system Key 1 axial force axis 2 tibial axis 3 0,07 w offset 4 holder of tibial component 5 cement mounting for tibi

28、al component 6 axial force applied through free turning pivot(s) Figure 2 Test specimen configuration BS ISO 14243-1:2009ISO 14243-1:2009(E) ISO 2009 All rights reserved 33.3 axial force force applied to the tibial component of the knee-joint prosthesis in a direction parallel to the tibial axis NOT

29、E The force is considered to be positive when it acts in an inferior-to-superior direction (see Figures 1 and 2). 3.4 axial force axis line 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 0,07 w 0,01 w in the medial d

30、irection from the tibial axis, where w is the overall width of the tibial component, as designated in ISO 7207-1 NOTE 1 See Figure 2. NOTE 2 The value of 0,07 w offset is equivalent to 5 mm offset for a tibial component of average width, i.e. 74 mm. 3.5 condylar centres centres of two circles which

31、are a best fit to the sagittal sections through the curved surfaces of the posterior regions of the two condyles of the femoral component of a condylar or meniscal total knee-joint prosthesis 3.6 flexion/extension axis nominal axis of rotation of the femoral component relative to the tibial componen

32、t NOTE 1 For hinged knees, the flexion/extension axis is the hinge axis. NOTE 2 For condylar and meniscal knees, the flexion/extension axis may be determined by: considering the condyles of the femoral component to be in contact with an imaginary plane perpendicular to the tibial axis when the femor

33、al component is at 30 and when it is at 60 of flexion; and then visualising four lines (contact normals) normal to the imaginary plane running through the points where the two femoral components would contact the plane at each of these flexion angles. The flexion/extension axis is then the line inte

34、rsecting all four contact normals. NOTE 3 The axis of rotation of the femoral component relative to the machine frame does not necessarily coincide with, but can be made to approximate to, the flexion/extension axis. 3.7 reference position angular and linear alignment of the tibial component relativ

35、e 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 on the lowest points on the tibial bearin

36、g surface NOTE 1 The reference position is equivalent to the position of 0 flexion (i.e. full extension) in vivo. NOTE 2 For the purpose of determining the reference position, the effect of friction between the tibial and femoral components is ignored. NOTE 3 The reference position may be determined

37、 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 and femoral surfaces can be taken either from design data or from co-ordinate measurements of an unworn total knee-joint prosthesis. NOTE

38、 4 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 lowest points on the tibial bearing surface can span a large (flat) range of anterior-posterior positions, or would not exist (no dish effect). I

39、n such a situation, this definition of reference position cannot apply. In such situations, the prosthesis manufacturer should be consulted to decide what neutral position should be set and this should be noted in detail in the test report. BS ISO 14243-1:2009ISO 14243-1:2009(E) 4 ISO 2009 All right

40、s reserved3.8 tibial axis nominal longitudinal axis of the tibia, corresponding to the central axis of the medullary cavity of the proximal tibia 3.9 tibial rotation rotation of the tibial component of the knee-joint prosthesis about the axial force axis NOTE The rotation is considered to be zero wh

41、en the total knee-joint prosthesis is in the reference position (3.7). This rotation is +ve when it is internal (see Figure 1). This means that for a left-sided total knee-joint prosthesis, the tibial rotation is positive when a view from a superior position on the tibial component shows the tibial

42、component rotated clockwise from its position with the total knee-joint prosthesis in the reference position (3.7). 3.10 tibial rotation torque torque applied to the tibial component of the total knee-joint prosthesis around the axial force axis NOTE From a plan view on the tibial component, the axi

43、al torque is +ve when it acts clockwise on a left-sided total knee-joint prosthesis (see Figure 1) and +ve when it acts anti-clockwise on a right-sided total knee-joint prosthesis. 4 Principle The total knee-joint prosthesis is mounted in an apparatus which applies a cyclic variation of flexion/exte

44、nsion angle and contact force to the interface between tibial and femoral components, simulating normal human walking. The tibial component is free to move relative to the femoral component under the influence of the applied contact forces, this motion having all degrees of freedom except for the fl

45、exion/extension angle which follows a specified cyclic variation. The applied contact force actions are axial force, anterior posterior (AP) force and tibial rotation torque. The axial force follows a specified cyclic variation. The AP force comprises two components, one being a specified cyclic var

46、iation and the other having a magnitude which depends on, and is in the opposite direction to, AP displacement. Similarly, the tibial rotation torque comprises two components, one being a specified cyclic variation and the other a rotation torque having a magnitude that depends on, and is in the opp

47、osite direction to, tibial rotation. The load actions that depend on the AP displacement and tibial rotation correspond to the tensions transmitted by anatomical ligaments in normal knee-joint function. The restraint as a function of AP displacement and rotation is described in 6.9 and 6.10. The con

48、tacting surfaces of the femoral and tibial components are immersed in a fluid test medium simulating human synovial fluid. If polymers are the object of investigation, a control specimen is subjected to the fluid medium and, optionally, to the same time-varying force to determine the creep of the te

49、st specimen and/or the amount of mass change due to fluid transfer. The test takes place in a controlled environment simulating physiological conditions. 5 Specimens and lubricants 5.1 Fluid test medium, calf serum diluted with deionized water to have a protein mass concentration of 20 g/l. Normally the fluid test medium is filtered through a 2 m filter. To minimize microbial contamination, the fluid test medium should be stored frozen until required for test. An anti-microbial reagent (such as sodium azid