欢迎来到麦多课文档分享! | 帮助中心 海量文档,免费浏览,给你所需,享你所想!
麦多课文档分享
全部分类
  • 标准规范>
  • 教学课件>
  • 考试资料>
  • 办公文档>
  • 学术论文>
  • 行业资料>
  • 易语言源码>
  • ImageVerifierCode 换一换
    首页 麦多课文档分享 > 资源分类 > PDF文档下载
    分享到微信 分享到微博 分享到QQ空间

    ASTM F1798-1997(2008) Standard Guide for Evaluating the Static and Fatigue Properties of Interconnection Mechanisms and Subassemblies Used in Spinal Arthrodesis Implants《脊椎关节固定术植入用.pdf

    • 资源ID:535691       资源大小:168.06KB        全文页数:10页
    • 资源格式: PDF        下载积分:5000积分
    快捷下载 游客一键下载
    账号登录下载
    微信登录下载
    二维码
    微信扫一扫登录
    下载资源需要5000积分(如需开发票,请勿充值!)
    邮箱/手机:
    温馨提示:
    如需开发票,请勿充值!快捷下载时,用户名和密码都是您填写的邮箱或者手机号,方便查询和重复下载(系统自动生成)。
    如需开发票,请勿充值!如填写123,账号就是123,密码也是123。
    支付方式: 支付宝扫码支付    微信扫码支付   
    验证码:   换一换

    加入VIP,交流精品资源
     
    账号:
    密码:
    验证码:   换一换
      忘记密码?
        
    友情提示
    2、PDF文件下载后,可能会被浏览器默认打开,此种情况可以点击浏览器菜单,保存网页到桌面,就可以正常下载了。
    3、本站不支持迅雷下载,请使用电脑自带的IE浏览器,或者360浏览器、谷歌浏览器下载即可。
    4、本站资源下载后的文档和图纸-无水印,预览文档经过压缩,下载后原文更清晰。
    5、试题试卷类文档,如果标题没有明确说明有答案则都视为没有答案,请知晓。

    ASTM F1798-1997(2008) Standard Guide for Evaluating the Static and Fatigue Properties of Interconnection Mechanisms and Subassemblies Used in Spinal Arthrodesis Implants《脊椎关节固定术植入用.pdf

    1、Designation: F 1798 97 (Reapproved 2008)Standard Guide forEvaluating the Static and Fatigue Properties ofInterconnection Mechanisms and Subassemblies Used inSpinal Arthrodesis Implants1This standard is issued under the fixed designation F 1798; the number immediately following the designation indica

    2、tes the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers the measurement of uniaxia

    3、l staticand fatigue strength, and resistance to loosening of the com-ponent interconnection mechanisms of spinal arthrodesis im-plants.1.2 The purpose of this guide is to provide a means ofmechanically characterizing different designs of spinal implantinterconnections. Ultimately, the various compon

    4、ents and in-terconnections should be combined for static and fatiguetesting of the spinal implant construct. It is not the intention ofthis guide to address the analysis of spinal implant constructsor subconstructs or to define levels of performance of spinalimplants as insufficient knowledge is ava

    5、ilable to predict theconsequences of the use of particular spinal implant designs.1.3 This guide sets out definitions for use in measuring thestrength of component interconnections of spinal implants,possible test methods themselves, and the reporting of testresults.1.4 The values stated in SI units

    6、 are to be regarded asstandard, with the exception of angular measurements, whichmay be reported in terms of either degrees or radians.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to est

    7、ablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing MachinesF 383 Practice for Static Bend and Torsion Testing ofIntramedullary Rods3F 1582 Te

    8、rminology Relating to Spinal Implants3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 active length of longitudinal elementthe span be-tween rigid supports (for example, 50 mm is the active lengthin Fig. 1, Fig. 2, Fig. 3(a), Fig. 3(b), and Fig. 4.3.1.2 global coordinate system

    9、spinal column motion hassix degrees of freedom, having translational motion along, androtational motion about three axes. The axes are labeledanterior-posterior or a-p (X), medial-lateral or transverse (Y),and caudal-cranial or axial (Z). This coordinate system is righthanded with +X in the anterior

    10、 direction, +Y towards the leftside of the body, and +Z in the cranial direction. Positiverotations are defined by the right hand rule (see Fig. 5(a).3.1.3 gripping capacitythe maximum applied load ormoment across an interconnection mechanism within the first1.5 mm of permanent displacement or 5 of

    11、permanent rotationbetween the connected components.3.1.4 local coordinate systemthe spines global coordi-nate system shall be applied locally at the position of theinterconnection. The local direction, z, shall be centeredthrough the longitudinal element of the x-y plane. The localdirection, x, shal

    12、l be defined as parallel to the axis of a screwor back of a hook. The local transverse axis, y, shall be parallelto a transverse element (See Fig. 5(b) and Fig. 5(c).3.1.5 loosening torquethe torque required to disconnectthe various threaded fasteners that might comprise the im-plants interconnectio

    13、n mechanism.3.1.6 major directions of loadingdirections of the pre-dominant forces and moments (relative to the local axes) towhich vertebral connection elements are subjected, (that is,axial load, Fz; A-P load, Fx; axial torsion, Mz; and flexion-extension moment, My).1This guide is under the jurisd

    14、iction of ASTM Committee F04 onMedical andSurgical Materials and Devices .Current edition approved Dec. 1, 2008. Published December 2008. Originallyapproved in 1997. Last previous edition approved in 2003 as F 1798 97(2003).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcont

    15、act 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 States.3.1.7 maxim

    16、um run out load/momentthe maximum loador moment that can be applied to a subassembly where all thetested constructs have withstood 2.5 3 106 cycles without afailure.3.1.8 relevant directions of loadingthose directions ofloading in which a particular component interconnection isdesigned to provide re

    17、sistance to loading. For example, aparticular spinal hook may be designed to withstand a positiveaxial load, A-P load, and flexion-extension moment, but not anegative axial load or axial torsion. Hence, positive axial load,A-P load, and flexion-extension moment are the relevantdirections of loading.

    18、3.1.9 spinal arthrodesis implantan implant applied to thespine with the intention of providing temporary correction andstability to vertebrae while bony fusion occurs.3.1.10 subassembly failurepermanent deformation result-ing from fracture, plastic deformation, loosening or slippagethat renders the

    19、subassembly ineffective or unable to ad-equately resist load.3.1.11 subassembly permanent deformationthe displace-ment (mm) or angular displacement (degree of the subassem-bly relative to the unloaded condition) remaining after theapplied load moment or torque has been removed. Care mustbe taken to

    20、ensure that the loading fixtures are rigid and do notcontribute to the measurement of deflection.3.1.12 tightening torquethe specified torque that is ap-plied to the various threaded fasteners that might comprise theimplants interconnection mechanism.3.1.13 ultimate load/moment of the subassemblymax

    21、imum load or moment applied to a subassembly (see PointEinFig. 6).3.1.14 yield load/moment of the subassemblythe load ormoment required to produce a permanent deformation equal to0.020 times the active length of the longitudinal element (seePoint D in Fig. 6).4. Summary of Test Methods4.1 Vertebral

    22、attachment components (for example, hook,screws, bands) and transverse elements must be attached tolongitudinal elements (for example, rods, plates) to form spinalimplant subassemblies.4.2 The interconnections are tested only in the relevantdirections of loading by applying loads at specific locatio

    23、nsrelative to the local coordinate system.4.3 The interconnections and subassemblies are tested stati-cally in a load-to-failure mode and also can be tested cyclicallyto estimate the maximum run out value at 2.5 3 106cycles.5. Significance and Use5.1 Spinal implants are generally composed of several

    24、components that, when connected together, form a spinalimplant construct. Spinal implant constructs are designed toprovide some stability to the spine while arthrodesis takesplace. This guide outlines standardized evaluations of differentinterconnection mechanisms to facilitate comparison betweendif

    25、ferent designs. Comparisons must be made cautiously andwith careful analysis, taking into account the effects that designdifferences can have on the loading configurations.5.2 This guide is used to quantify the static and fatigueproperties of different implant interconnection designs. Themechanical

    26、tests are conducted in vitro using simplified,unidirectional loads and moments. Fatigue testing in a simu-lated body fluid or saline may have a fretting, corrosive, orlubricating effect on the interconnection and thereby affect therelative performance of tested devices. Hence, the test envi-ronment,

    27、 whether a simulated body fluid, saline (9g NaCl per1000 mL H2O), with a saline drip, or dry, is an importantcharacteristic of the test and must be reported accurately.5.3 The loading of spinal implant constructs in vivo will, ingeneral, differ from the loading configurations used in thisguide. The

    28、results obtained here cannot be used directly topredict in vivo performance. However, the results can be usedto compare different component designs in terms of relativemechanical parameters.FIG. 1 A-P Test Apparatus for SubassemblyFIG. 2 Transverse Test Apparatus for SubassemblyF 1798 97 (2008)2FIG.

    29、 3 Flexion-Extension Moment Test Apparatus for SubassemblyF179897(2008)36. Apparatus6.1 Machines used for the test shall conform to the require-ments of Practices E4.6.2 The apparatus for axial (z) gripping capacity measure-ments of an interconnection mechanism is depicted in Fig.7(a). One end of th

    30、e longitudinal element shall be clampedrigidly, leaving 5 mm exposed between the interconnectionmechanism and the test machine base.Asection of longitudinalelement at least 5 mm shall extend beyond the interconnectionlinkage and remain unfixed. Axial loads are applied to theinterconnection mechanism

    31、 along the axis of the longitudinalelement via a sleeve (collar) which freely surrounds thelongitudinal element. The sleeve (collar) should evenly distrib-ute the load around the interconnection. An alternate method,depicted in Fig. 7(b), applies the load to the longitudinalelement and pushes it thr

    32、ough the interconnection clamp.6.3 The apparatus forA-P (x) mechanical property measure-ments of a subassembly is depicted in Fig. 1. Both ends of thelongitudinal element shall be clamped rigidly, with the inter-connection centered on a 50-mm section of the longitudinalelement. The local origin of t

    33、he interconnection mechanismshall be centered between the mounts. Loads are applied to theinterconnection (perpendicular to the longitudinal element) viaa clamp on the hook, screw, or band. The load should becentered through the local x coordinate axis.6.4 The apparatus for transverse (y) mechanical

    34、 propertymeasurements of a subassembly is depicted in Fig. 2. Bothends of the longitudinal element shall be clamped rigidly, withFIG. 4 Transverse Moment Test Apparatus for SubassemblyF 1798 97 (2008)4FIG. 5 Coordinate SystemF 1798 97 (2008)5the interconnection centered on a 50-mm section of thelong

    35、itudinal element. The local origin of the interconnectionmechanism shall be centered between the mounts. Loads areapplied to the interconnection (perpendicular to the longitudi-nal element) via a clamp on the transverse connector. The loadshould be centered through the local y coordinate axis.6.5 Th

    36、e apparatus for flexion-extension moment (My) me-chanical property measurements of a subassembly is depictedin Fig. 3. Both ends of the longitudinal element shall beclamped rigidly, with the interconnection centered on a 50-mmsection of the longitudinal element. The local origin of theinterconnectio

    37、n mechanism shall be centered between theFIG. 6 Load/Displacement CurveF 1798 97 (2008)6mounts. Loads are applied to the interconnection (parallel tothe longitudinal element). For spinal hooks, the load shall beapplied via a cylinder set in the hook notch (see Fig. 3(a). Forother elements (screws) t

    38、he load shall be applied 25 mm fromthe local z axis (see Fig. 3(b).6.6 The apparatus for transverse moment (Mx) mechanicalproperty measurements of a subassembly is depicted in Fig. 4.As in the previous test, 6.5, both ends of the longitudinalelement shall be clamped rigidly, with the interconnection

    39、centered on a 50-mm section of the longitudinal element. Thelocal origin of the interconnection mechanism shall be centeredbetween the mounts. Loads are applied to the interconnection(parallel to the longitudinal element), 25 mm from the z axis.6.7 The apparatus for axial torque (Mz) gripping capaci

    40、tymeasurements of an interconnection mechanism is depicted inFig. 8(a) and is similar to that described in 6.2 with theexception that the axial torque is applied via notches in thesleeve that surrounds the longitudinal element. An alternativemethod is to hold the interconnection rigidly and apply th

    41、etorsional force to the longitudinal element as shown in Fig.8(b). A third alternative is to apply the torque via a forceapplied to a moment arm as shown in Fig. 8(c), but thisalternative may introduce an additional variable of bending ofthe anchor component. In any case, care must be taken toevalua

    42、te and minimize the effect of the torsional properties ofthe longitudinal element on the results.7. Sampling7.1 The samples tested shall be previously unused parts, andshall not be re-tested.7.2 The test constructs shall be labeled and maintainedaccording to good laboratory practice.7.3 Static tests

    43、 of mechanical properties should have aminimum sample size of five.7.4 Fatigue tests for determining the maximum run out loador moment of a subassembly at 2.5 3 106cycles shall utilize arun down, half-interval approach4with one specimen per rundown interval or half-interval and three consecutive spe

    44、cimensshowing run out to 2.5 3 106cycles. Alternative methods fordetermining the starting point of the fatigue curve are therun-up method or choosing 75 % of the ultimate static load ormoment.8. Procedure for Measuring Static Mechanical Properties8.1 Measure the tightening torques for any set screws

    45、 ornuts which are incorporated into the interconnection linkage.8.2 Apply all tightening, crimping, or locking mechanismsas specified by the manufacturer.8.3 The recommended maximum rate for applying a load is20 N/s (or 25 mm/min) and is 25 N-m/min (or 25 /min) forapplying a moment or torque. Since

    46、rate is machine- andsoftware-dependent, it may be necessary to run the tests slowerto achieve accurate data.8.4 StaticA-P load (Fx), transverse load (Fy), axial grippingcapacity (Fz), and transverse moment (Mx), flexion-extensionmoment (My), and axial torque (Mz) shall be measured usingthe apparatus

    47、 described in 6.1-6.7.8.5 Loads and moments need to be measured only in therelevant directions of loading.8.6 After each load or moment measurement, looseningtorque shall be measured (if applicable).4“Optiminal Stress Amplitude Selection in Estimating Median Fatigue LimitsUsing Small Samples”, Littl

    48、e, R.E., ed., J. of Testing and Evaluation, ASTM, 1990,pp. 115122.FIG. 7 Axial Gripping Capacity Test ApparatusF 1798 97 (2008)7FIG. 8 Axial Torque Gripping Capacity Test ApparatusF 1798 97 (2008)89. Procedure for the Measurement of Fatigue Run Out9.1 Measure the tightening torques for any set screw

    49、s ornuts that are incorporated into the connection linkage.9.2 Apply all tightening, crimping, or locking mechanismsas specified by the manufacturer.9.3 The maximum frequency of cyclic loading is not speci-fied but shall be measured and reported.9.4 All fatigue loading should be sinusoidal, accomplishedvia continuous load amplitude control, rather than in a con-trolled deflection manner.9.5 A-P fatigue run out (Fx), transverse fatigue run out (Fy),axial fatigue run out (Fz), transverse moment fatigue run out(Mx), flexion extension moment fatigue ru


    注意事项

    本文(ASTM F1798-1997(2008) Standard Guide for Evaluating the Static and Fatigue Properties of Interconnection Mechanisms and Subassemblies Used in Spinal Arthrodesis Implants《脊椎关节固定术植入用.pdf)为本站会员(fatcommittee260)主动上传,麦多课文档分享仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知麦多课文档分享(点击联系客服),我们立即给予删除!




    关于我们 - 网站声明 - 网站地图 - 资源地图 - 友情链接 - 网站客服 - 联系我们

    copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
    备案/许可证编号:苏ICP备17064731号-1 

    收起
    展开