Significance and Use
5.1 This in-vitro test method includes the use of cyclic forces to evaluate the fatigue strength of acetabular shells or monoblock acetabular devices used in THR.
5.2 Fracture or cracking of acetabular shells or monoblock acetabular devices in THR, although rare, does occur.
Scope
1.1 This test method is intended to evaluate the fatigue strength of metallic acetabular shells with hemispheric outer surfaces.
1.2 This test method, as described, is not intended to evaluate the following: the strength of components that may be mated with the acetabular shells (for example, augments, acetabular liners); attributes of the shells not related to strength (for example, fixation, coating adhesion); the strength of acetabular shell features away from, or loaded differently than, the primary load bearing region of the shell (for example, screws, spikes, flanges); non-hemispherical shells (for example, patient-matched geometries); or corrosion between modular components.
1.3 Modifications to this test method (for example, different support medium, different size/position of unsupported region, different testing environment) may result in a method appropriate to evaluate the characteristics listed in 1.2. Such modification must have adequate justification.
1.4 Although the methodology described does not replicate all physiological force conditions, it is a means of in vitro comparison of acetabular device designs under repeated forces.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.