ASTM_F_2267_-_04_2011.pdf

Designation:F226704(Reapproved 2011)Standard Test Method forMeasuring Load Induced Subsidence of Intervertebral BodyFusion Device Under Static Axial Compression1This standard is issued under the fixed designation F2267;the number immediately following the designation indicates 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 test method specifies the materials and methods forthe axial compressive subsidence testing of non-biologic in-tervertebral body fusion devices,spinal implants designed topromote arthrodesis at a given spinal motion segment.1.2 This test method is intended to provide a basis for themechanical comparison among past,present,and future non-biologic intervertebral body fusion devices.This test method isintended to enable the user to mechanically compare interver-tebral body fusion devices and does not purport to provideperformance standards for intervertebral body fusion devices.1.3 This test method describes a static test method byspecifying a load type and a specific method of applying thisload.This test method is designed to allow for the comparativeevaluation of intervertebral body fusion devices.1.4 Guidelines are established for measuring test blockdeformation and determining the subsidence of intervertebralbody fusion devices.1.5 Since some intervertebral body fusion devices requirethe use of additional implants for stabilization,the testing ofthese types of implants may not be in accordance with themanufacturers recommended usage.1.6 UnitsThe values stated in SI units are to be regardedas the standard with the exception of angular measurements,which may be reported in terms of either degrees or radians.1.7 The use of this standard may involve the operation ofpotentially hazardous equipment.This standard does not pur-port to address all of the safety concerns,if any,associatedwith its use.It is the responsibility of the user of this standardto establish appropriate safety and health practices anddetermine the applicability of regulatory limitations prior touse.2.Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing MachinesF1582 Terminology Relating to Spinal ImplantsF1839 Specification for Rigid Polyurethane Foam for Use asa Standard Material for Testing Orthopaedic Devices andInstrumentsF2077 Test Methods For Intervertebral Body Fusion Devices3.Terminology3.1 All subsidence testing terminology is consistent with thereferenced standards above,unless otherwise stated.3.2 Definitions:3.2.1 coordinate system/axesthree orthogonal axes aredefined by Terminology F1582 as seen in Fig.4.The center ofthe coordinate system is located at the geometric center of theintervertebral body fusion device assembly.The X-axis is alongthe longitudinal axis of the implant,with positive X in theanterior direction,Y is lateral,and Z is cephalic.3.2.2 ideal insertion locationthe implant location withrespect to the simulated inferior and superior vertebral bodies(polyurethane)dictated by the type,design,and manufacturerssurgical installation instructions.3.2.3 intended method of applicationintervertebral bodyfusion devices may contain different types of stabilizingfeatures such as threads,spikes,and knurled surfaces.Eachtype of feature has an intended method of application orattachment to the spine.3.2.4 intended spinal locationthe anatomic region of thespine intended for the intervertebral body fusion device.Intervertebral body fusion devices may be designed anddeveloped for specific regions of the spine such as the lumbar,thoracic,and cervical spine.Also,there potentially existdifferent anatomical surgical approaches,which will result indifferent implant orientation at different levels of the spine.1This test method is under the jurisdiction ofASTM Committee F04 on Medicaland Surgical Materials and Devicesand is the direct responsibility of SubcommitteeF04.25 on Spinal Devices.Current edition approved Dec.1,2011.Published January 2012.Originallyapproved in 2003.Last previous edition approved in 2004 as F2267 04.DOI:10.1520/F2267-04R11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.5 intervertebral subsidencethe process of a vertebralbody cavitating or sinking around an implanted intervertebralbody fusion device resulting in the loss of intradiscal height.3.2.6 intradiscal heightthe straight-line distance along theZ-axis between the unaltered simulated vertebral bodies.SeeFig.1.FIG.1 Intradiscal Height DiagramFIG.2 Typical Load-Displacement Curve with 1.5 mm(Thoracic Device)Offset f