1、Designation: F2582 08F2582 14Standard Test Method forImpingement of Acetabular Prostheses1This standard is issued under the fixed designation F2582; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers a procedure for measuring the range of motion, impingement, and dislocation of a to evaluateacetabular component fat
3、igue, deformation, and wear and femoral head assembly and acetabular prosthesis.dislocation underdynamic impingement conditions.1.2 This test method covers the procedure for static and cyclic fatigue tests.1.2 This test method maycan be used to evaluate single piece single-piece acetabular prosthese
4、s, modular prostheses, andconstrained prostheses manufactured from polymeric, metallic, or ceramic materials.1.3 The values stated in SI units are regarded as the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibil
5、ityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing MachinesE467 Practice for Verification of Constant Ampl
6、itude Dynamic Forces in an Axial Fatigue Testing SystemF2003 Practice for Accelerated Aging of Ultra-High Molecular Weight Polyethylene after Gamma Irradiation in AirF2033 Specification for Total Hip Joint Prosthesis and Hip Endoprosthesis Bearing Surfaces Made of Metallic, Ceramic, andPolymeric Mat
7、erialsF2091 Specification for Acetabular Prostheses2.2 ISO Standards:3ISO 7206-1 Implants for Surgery Partial and Total Hip Joint Prostheses Part 1: Classification and Designation of DimensionsISO 14242-1 Implants for Surgery Wear of Total Hip-Joint Prostheses Part 1: Loading and Displacement Parame
8、ters forWear-Testing Machines and Corresponding Environmental Conditions for TestISO 14242-2 Implants for Surgery Wear of Total Hip-Joint Prostheses Part 2: Methods of MeasurementISO 21535 Non-Active Surgical Implants Joint Replacement Implants Specific Requirements for Hip-Joint ReplacementImplants
9、3. Terminology3.1 Definitions:3.1.1 component separationthe disruption of a connection between components. May be stable or unstable.3.1.2 dislocationthe loss of normal physical contact between opposing components, usually indicated by large separation anda loss of stability.3.1.3 dislocation moment
10、the maximum torsional moment (N-m) measured at the point of dislocation. See Fig. 6.3.1.3 femoral headconvex spherical bearing member for articulation with the natural acetabulum or prosthetic acetabulum.1 This test method is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Mater
11、ials and Devices and is the direct responsibility of SubcommitteeF04.22 on Arthroplasty.Current edition approved June 1, 2008April 1, 2014. Published July 2008April 2014. Originally approved in 2008. Last previous edition approved in 2008 as F2582 08. DOI: 10.1520/F2582-08.10.1520/F2582-14.2 For ref
12、erencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from International Organization for Standardization (ISO),
13、 1, ch. de la Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to ad
14、equately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshoh
15、ocken, PA 19428-2959. United States13.1.4 impingementthe point at which two opposing components collide to restrict motion, usually indicated by a sharp changein force or moment. See motion.Fig. 3 and Fig. 6.3.1.6 impingement momentthe moment (N-m) measured or applied at the point of impingement.3.1
16、.5 joint reaction forcethe force directed normal to the contacting surfaces between two opposing articulating components.entry diameter of the acetabular prosthesis (see ISO 7206-1).3.1.6 locking mechanismthe pieces of various components that contribute to the fixing of one component to another.3.1.
17、7 range of motionthe effective pattern of motion limited by impingement. In one plane this is measured from oneimpingement point to the opposite impingement point.3.1.8 subluxationpartial dislocation.4. Summary of Test Method4.1 Acetabular prostheses are evaluated for range of motion until impingeme
18、nt. The impingement behavior is measured up toa dislocation or failure point. fatigue, deformation, and wear under repeated impingement conditions. Modular acetabularprostheses mayshould be evaluated for additional failure mechanisms including separation, loosening, fracture, and deformationof any c
19、omponent or locking mechanism, or both.4.2 This test method maycan be used to evaluate static or dynamic characteristics. Various joint reaction forces andimpingements maycan be applied in order to simulate known clinical conditions.5. Significance and Use5.1 TheThis test method mayshould be used to
20、 evaluate and compare acetabular prostheses to assess the relative degree ofconstraint for the prosthesis and the damage tolerance under controlled laboratory conditions.FIG. 2 Schematic Representation of the Test SetupNOTE 1The acetabular and femoral prostheses should have freedom to move relative
21、to each other in the plane perpendicular to the joint reactionforce. Flexion-extension (FE), abduction-adduction (AA), and internal-external (IE) rotations are relative motions between the acetabular and femoralprostheses.FIG. 31 Schematic Representation Principle of the Test Setup at the PointSet-U
22、pof ImpingementF2582 1425.2 It is recognized that there are several clinical failure modes for acetabular prostheses and that this test method may or maynot be capable of reproducing them.Although the methodology described attempts to identify physiologically relevant motions andloading conditions,
23、the interpretation of results is limited to an in vitro comparison between acetabular prosthesis designs regardingconstraint and their ability to resist impingement fatigue, wear, deformation, and dislocation under the stated test conditions.6. Apparatus for Impingement6.1 One axis mustshall be capa
24、ble of applying either a constant joint reaction force for static and dynamic loading or aphysiological waveform for dynamic loading.6.2 A second axis mustThree motion axes shall be capable of controlling and monitoring angular displacement andtorque.displacement.6.3 The equipment may be electromech
25、anical, servo-hydraulic or other, as long as it meets the requirements of Practices E4 andE467 for force verification.6.4 The joint reaction force mustshall be applied through unconstrained fixturing that allows for the separation of the acetabularprosthesis from the femoral prosthesis during the im
26、pingement and dislocation test. See Fig. 1 for representative fixture. See Fig.2 for the test set-up.principle.7. Sampling and Test Specimens7.1 All acetabular and femoral head components shall be representative of implant quality products. This shall include anysterilization processes if the steril
27、ization may affect the results.7.2 Femoral neck components shall have geometries representative of finished product but may be manufactured fromnon-implant grade materials.FIG. 42 An Example Test SetupMotions for Impingement Wear TestingFIG. 5 An Example Test Setup Showing the Point of ImpingementF2
28、582 1437.2 A minimum of five assembliesthree samples shall be tested under any set of boundary conditions chosen to determine thestatic range of motion and dislocationimpingement wear. Three additional samples should be used as reference samples withoutimpingement in order to provide a comparison to
29、 the amount of mode 1 wear4 moment.that would otherwise occur if the primarysamples were not impinging.7.4 Multiple tests may be performed on each specimen. The appropriateness of performing multiple tests on the samecomponents will depend on the type of testing and will require careful monitoring a
30、nd reporting of component properties.7.3 Precondition the specimens for 24 h inaccording to Practice F2003 the laboratory test environment, for example 25 6 3Cand 50 6 10 % relative humidity (RH).(artificial aging).7.4 Precondition the specimens for 48 h in the test environment if this is water at 3
31、762C.according to ISO 14242-2 (soaking).8. Procedure8.1 Static Range of Motion (ROM) and Dislocation Testing: Test Procedure:8.1.1 Weigh the acetabular inserts as described by ISO 14242-2.8.1.2 Measure the original (unworn) geometry of the impingement section of the acetabular insert.8.1.3 See Fig.
32、21 for a schematic representation of the test setup. See Figs. 4 and 5 for an example setup for testing.8.1.4 Mount the acetabular prosthesis with the entry diameter plane orthogonal to the direction on the main joint reaction forceimposed by the simulator.8.1.5 Mount a femoral head assembly on the
33、main joint reaction force actuator. The the femoral prosthesis separately, such thatthe simulator actuators allow for relative motion with the acetabular component, providing flexion/extension, abduction-adduction,and internal-external rotation. The femoral component assembly shall consist of a femo
34、ral head and stem neck region for theminimum length that may contact the acetabular component.8.1.6 Adjust the simulator actuators for the hip assembly to have zero internal/external rotation and zero flexion/extension.NOTE 1Computer analysis as well as range of motion testing as described by ISO 21
35、535 might support the adjustment of the reference position.8.1.7 Mount an acetabular prosthesis onto a separate but orthogonal actuator (an axis perpendicular to the mainApply a constantjoint reaction force axis). Careful attention should be given to the position of the acetabular component relative
36、 to the center ofthe actuator that will rotate the component (see of 600 N.Fig. 2).8.1.4 Static tests do not require lubricant but water may be used if desired.8.1.5 Apply a joint reaction force.Aforce of 225 N is recommended for evaluation of range of motion. Higher forces may alsobe used and 1000
37、N is recommended for determination of boundary conditions for dynamic testing.8.1.8 Rotate the acetabular prosthesis around the a subset of three test assemblies around the center of the femoral head underangular displacement control in abduction motion until impingement occurs in the direction of r
38、otation. An angular displacementrate of 5/s is recommended. Measure the total range of motion up torotation of these test samples occurs. With this starting pointand the abduction motion described in Fig. 2the impingement point in both directions of rotation., impingement will occurthroughout the en
39、tire test cycle.NOTE 1This test method evaluates characteristics of acetabular prostheses in one plane and many prostheses exist as asymmetric designs. Thevariation in geometry of any single prosthesis may be evaluated by choosing different orientations for the initial positioning of the prosthesis
40、and thenrepeating the measurement procedure. Physiologically relevant positions may be tested by changing the position of the acetabular cup.Atypical positionwould place the acetabular component at an angle to replicate a 45 superior inclination while measuring ROM and dislocation events during rota
41、tionthat simulates a flexion/extension action of the femoral component.8.1.9 Adjust the other subset (optional) of three assemblies (control samples) in a position which allows for a minimum of 5of abduction motion before contacting the acetabular component.NOTE 2The contact conditions shall represe
42、nt the worst cast in-vivo situation. Internal/external rotation or flexion/extension of the stem, or both, shallbe considered.NOTE 3Computer models may be used to evaluate the worst-case impingement.NOTE 4Testing of constrained prostheses will require additional mechanical or electronic systems, or
43、both, to limit the test load to the joint reactionforce of 600 N.NOTE 5Soak control samples (loaded or unloaded) might be used to correct wear measurements for fluid absorption of the specimens.NOTE 2Computer models may be used to evaluate the range of motion of acetabular prostheses.8.1.10 The test
44、 fluid and test chamber shall be in accordance with ISO 14242-1.8.1.11 The relative motion between the femoral stem and the acetabular cup about the reference position (see 8.1.7 and 8.1.8)shall be 0 to 5 for abduction, -5 to 5 for internal/external rotation, and 0 to 10 for extension. See Fig. 2 fo
45、r phasing of theindividual motions.8.1.12 The dislocation moment may be measured by continuing the angular displacement beyond impingement until dislocationoccurs.maximum test frequency shall be 3 Hz.FIG. 1 Representative Unconstrained Planar Bearing Fixture for Femoral Component4 McKellop, H. A., “
46、The Lexicon of Polyethylene Wear in Artificial Joints,” Biomaterials, Vol 28, 2007, pp. 50495057 (Definition of wear modes).F2582 144NOTE 3The angular displacement rate may be adjusted to simulate the intended cyclic test rate.8.1.13 Determine the acetabular component weight as described by ISO 1424
47、2-2 at 0.2 million cycle intervals.8.1.14 Measure the dislocation moment with an apparatus that has an accuracy of at least 0.2 N-m.Ensure that the impingementtest specimens are in contact with the acetabular component at each test interval starting point. Readjustment of the referenceposition might
48、 become necessary due to wear and deformation of the components.8.1.15 Test for a maximum of one million cycles or failure, whichever comes first. Failure is defined in 8.2.8.1.16 Continuously record torque and displacement data at a sufficient rate to capture the peak moment and provide a graphof m
49、oment versus angular displacement (seeMeasure the final surface geometry of the worn impingement section of Fig. 6).theacetabular insert and determine the volume difference between the original and the final geometry.8.2 Unidirectional Dynamic Impingement Testing:8.2.1 This method may be used for the unidirectional cyclic or dynamic evaluation of acetabular prostheses with the followingconsiderations.8.2.2 An environment of water at 37 6 2C shall be used to provide lubrication and temperature control during the test.8.2.3 A constant
