Standard Test Method for Determination of Total Knee Replacement Constraint

SCOPE
1.1 This test method covers the establishment of a database of total knee replacement (TKR) motion characteristics with the intent of developing guidelines for the assignment of constraint criteria to TKR designs. (See the Rationale in .Appendix X1)
1.2 This test method covers the means by which a TKR constraint may be quantified according to motion delineated by the inherent articular design as determined while under specific loading conditions in an in vitro environment.
1.3 Tests deemed applicable to the constraint determination are antero-posterior draw, medio-lateral shear, rotary laxity, valgus-varus rotation, and distraction, as applicable. Also covered is the identification of geometrical parameters of the contacting surfaces which would influence this motion and the means of reporting the test results. (See Practices E 4.)
1.4 This test method is not a wear test.
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
30-Sep-2004
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM F1223-04a - Standard Test Method for Determination of Total Knee Replacement Constraint
English language
8 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F 1223 – 04a
Standard Test Method for
1
Determination of Total Knee Replacement Constraint
This standard is issued under the fixed designation F 1223; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.2 anterior posterior (AP)—any geometrical length
aligned with the AP orientation.
1.1 This test method covers the establishment of a database
3.1.3 AP displacement—the relative linear translation be-
of total knee replacement (TKR) motion characteristics with
tween components in the AP direction.
the intent of developing guidelines for the assignment of
3.1.4 AP draw load—the force applied to the movable
constraint criteria to TKR designs. (See the Rationale in
component with its vector aligned in the AP direction causing
Appendix X1.)
or intending to cause an AP displacement.
1.2 This test method covers the means by which a TKR
3.1.5 biconcave—a condylar design with pronounced AP
constraint may be quantified according to motion delineated by
and MLcondylar radii seen as a “dish” in the tibial component
theinherentarticulardesignasdeterminedwhileunderspecific
or a “toroid” in the femoral component.
loading conditions in an in vitro environment.
3.1.6 bearing surface—those regions of the component
1.3 Tests deemed applicable to the constraint determination
which are intended to contact its counterpart for load transmis-
are antero-posterior draw, medio-lateral shear, rotary laxity,
sion.
valgus-varus rotation, and distraction, as applicable. Also
3.1.7 condyles—entity designed to emulate the joint
covered is the identification of geometrical parameters of the
anatomy and used as a bearing surface primarily for transmis-
contacting surfaces which would influence this motion and the
sion of the joint reaction force with geometrical properties
means of reporting the test results. (See Practices E 4.)
which tend to govern the general kinematics of the TKR.
1.4 This test method is not a wear test.
3.1.8 distraction—the separation of the femoral compo-
1.5 This standard does not purport to address all of the
nent(s) from the tibial component(s) in the z-direction.
safety concerns, if any, associated with its use. It is the
3.1.9 flexion angle—the angulation of the femoral compo-
responsibility of the user of this standard to establish appro-
nent (about an axis parallel to the y-axis) from the fully
priate safety and health practices and determine the applica-
extended knee position to a position in which a “local” vertical
bility of regulatory limitations prior to use.
axis on the component now points posteriorly.
2. Referenced Documents
3.1.9.1 Discussion—For many implants, 0° of flexion can
2
be defined as when the undersurface of the tibial component is
2.1 ASTM Standards:
parallel to the femoral component surface that in vivo contacts
E 4 Practices for Force Verification of Testing Machines
the most distal surface of the femur.This technique may not be
F 2083 Specification for Total Knee Prosthesis
possibleforsomeimplantsthataredesignedtohaveaposterior
3. Terminology
tilt of the tibial component. In these cases, the user shall
specify how the 0° of flexion position was defined.
3.1 Definitions—Items in this category refer to the geo-
3.1.10 hinge—a mechanical physical coupling between
metricalandkinematicaspectsofTKRdesignsastheyrelateto
femoral and tibial components which provides a singular axis
their human counterparts:
about which flexion occurs.
3.1.1 anterior curvature—a condylar design which is gen-
3.1.11 hyperextension stop—a geometrical feature which
erally planar except for a concave—upward region anteriorly
arrests further progress of flexion angles of negative value.
on the tibial component.
3.1.12 internal-external rotation—the relative angulation of
the moveable component about an axis parallel to the z-axis.
1
This test method is under the jurisdiction ofASTM Committee F04 on Medical
3.1.13 joint reaction force—the applied load whose vector
and Surgical Materials and Devices and is the direct responsibility of Subcommittee
is directed parallel to the z-axis, generally considered parallel
F04.22 on Arthroplasty.
to tibial longitudinal axis.
Current edition approved Oct. 1, 2004. Published October 2004. Originally
approved in 1989. Last previous edition approved in 2004 as F 1223 – 04.
3.1.14 medio-lateral (ML)—the orientation that is aligned
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
with the y-axis in the defined coordinate system.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3.1.15 ML condylar radius—the geometrical c
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.