ASTM F2694-26

1.1 This test method provides guidance for the functional, kinematic, and wear testing of motion-preserving total facet prostheses for the lumbar spine. These implants are intended to allow motion and lend support to the functional spinal unit(s) through replacement of the natural facets.

1.2 This test method is not intended to address the bone-implant interface or the static characteristics of the prosthesis components. Fatigue characteristics are included, but only as a by-product of cyclic wear testing under facet load and thus are not addressed in the typical process of generating a Stress-Life (S-N) characterization.

1.3 Biocompatibility of the materials used in a total facet prosthesis are not addressed in this test method.

1.4 The values stated in SI units are to be regarded as the standard with the exception of angular measurements, which may be reported in either degrees or radians.

1.5 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.

1.6 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.

4.1 This test method can be used to describe the function, kinematics, and wear behavior of total facet prostheses subjected to cyclic loading/motion for relatively large numbers of cycles. (For example, various designs of total facet prostheses, as well as the effects of materials, manufacturing techniques, and other design variables on one particular design can be studied using this test method.)

4.2 This test method is intended to be applicable to total facet prostheses that support and transmit motion by means of an articulating joint or by use of compliant materials. Ceramics, metals, and/or polymers may be used in total facet prosthesis design, and it is the goal of this test method to enable a kinematic wear comparison of these devices, regardless of material and type of device.