ASTM F2033-20

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. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F2033 − 12 F2033 − 20
Standard Specification for
Total Hip Joint Prosthesis and Hip Endoprosthesis Bearing
Surfaces Made of Metallic, Ceramic, and Polymeric
Materials
This standard is issued under the fixed designation F2033; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This specification covers the requirements for the mating bearing surfaces of total hip prostheses and hip endoprostheses. joint
prostheses or resurfacing hip devices, intended for total hip arthroplasty; and hip endoprostheses, intended for hemiarthroplasty.
More specifically, this specification covers hip joint replacement of the ball-and-socket configuration.
1.2 This specification covers the sphericity, surface finish requirements, and dimensional tolerances for the spherical articulating
metallic or ceramic femoral heads of total hip joint prostheses.
1.3 This specification covers the sphericity, and surface finish requirements, and dimensional tolerances requirements for the
spherical concave mating surface of metallic and ceramic acetabular components, including the inner polymeric bearing surface
of bipolar heads, and the surface finish requirements and dimensional tolerances for the spherical concave mating surface of
polymeric acetabular components.
1.4 This specification covers the sphericity and sphericity, surface finish requirements requirements, and dimensional tolerances
for the spherical metallic or ceramic femoral heads of hip endoprostheses, and the outer bearing surface of bipolar
heads.endoprostheses.
1.5 This specification covers the surface finish requirements and dimensional tolerances for the inner polymeric bearing surface
of bipolar hip components, and the sphericity and surface finish requirements of the inner metallic or ceramic bearing surface of
bipolar hip components; and the sphericity, surface finish requirements, and dimensional tolerances of outer metallic or ceramic
bearing surfaces of bipolar hip components of hip endoprostheses.
1.6 This specification is intended for standard practice regarding the design of total hip joint bearing surfaces. Additionally, the
tolerances imposed on the polymeric portion of the bearing surface are intentionally large due to temperature-induced size changes
and other manufacturing concerns. Some manufacturing methods or designs may intentionally reduce the diameter of the
polymeric bearing to more closely mate with the diameter of the head.
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
This specification is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices and is the direct responsibility of Subcommittee
F04.22 on Arthroplasty.
Current edition approved Feb. 15, 2012Oct. 1, 2020. Published March 2012December 2020. Originally approved in 2000. Last previous edition approved in 20052012
as F2033 – 05.F2033 – 12. DOI: 10.1520/F2033-12.10.1520/F2033-20.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2033 − 20
1.8 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.
1.9 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.
2. Referenced Documents
2.1 ISO Documents:
ISO 4287/14287:1997 Surface Roughness—Terminology Geometrical Product Specifications (GPS)—Surface texture: Profile
method—Terms, definitions and surface texture parameters
ISO 42914291:1985 Methods for the Assessment of Departure from Roundness, Measurement of Variations, andRoundness—
Measurement of Variations in Radius
ISO 5436-1:2000 Geometrical Product Specifications (GPS)—Surface texture: Profile method; Measurement standards—Part 1:
Material measures
ISO 54366318:1985 Surface Texture of Products—Calibration Specimens for Stylus InstrumentsMeasurement of roundness—
Terms, definitions and parameters of roundness
ISO 6318-198512181-1:2011 Measurement of Roundness—Terms, Definitions, and Parameters of Roundness (Equivalent to BS
3730 Part 1: 1987)Geometrical product specifications (GPS)—Roundness—Part 1: Vocabulary and parameters of roundness
ISO 7206-17206-1:2008 Implants for Surgery—Partial and Total Hip Joint Prosthesis—Part I: Classification, Designation of
Dimensions, and Requirementssurgery—Partial and total hip joint prostheses—Part 1: Classification and designation of
dimensions
ISO 7206-27206-2:2011 Implants for Surgery—Partial and Total Hip Joint Prosthesis—Part II: Bearing Surfaces Made of
Metallic and Plastics Materialssurgery—Partial and total hip joint prostheses—Part 2: Articulating surfaces made of metallic,
ceramic and plastics materials
ISO 7206-2:2011/Amd1:2016 Implants for surgery—Partial and total hip joint prostheses—Part 2: Articulating surfaces made
of metallic, ceramic and plastics materials + Amendment 1:2016
ISO 25178-2:2012 Geometrical product specifications (GPS)—Surface texture: Areal—Part 2: Terms, definitions and surface
texture parameters
2.2 ANSI/ASMEASME Document:
ANSI/ASME B46.1ASME B46.1-2009 -1995 Surface Texture (Surface Roughness, Waviness, and Lay)
3. Dimensions and Characteristics
3.1 Definition:Definitions:
3.1.1 pole of the articulating surface—cutoff length—The pole of an articulating surface is defined by a point at the intercept of
the revolution axis of the component and the spherical articulation surface.cutoff length defines the maximal value of the mean
twist of profile irregularities that shall be considered in the roughness measurement; that is, with a cutoff length of 0.8 mm, the
profile irregularities with a mean twist higher than 0.8 mm shall not be considered. Cutoff length requirements for bearing surfaces
covered by this standard are given in ISO 7206-2.
3.1.1.1 Precise definitions of roughness parameters, cutoff length, and roundness are given in ISO 4287, ISO 5436-1, ISO 4291,
and ISO 6318:1985.
3.1.2 equator of the articulating surface—The equator of the articulating surface is the circle normal to the revolution axis of the
component, the center of which is the center of the spherical articulating surface.
3.1.3 cutoff length—pole of the articulating surface—The cutoff length defines the maximal value of the mean twist of profile
irregularities that shall be considered in the roughness measurement, that is, with a cutoff length of 0.8 mm, the profile irregularities
with a mean twist higher than 0.8 mm shall not be considered. pole of an articulating surface is defined by a point at the intercept
of the revolution axis of the component and the spherical articulation surface.
3.1.3.1 Precise definitions of roughness parameters, cutoff length, and roundness are given in ISO 4287/1, ISO 5436, ISO 4291,
and ISO 6318:1985.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
www.asme.org.
F2033 − 20
3.1.4 stylus tip—The stylus tip is the tip of the measuring device (diamond or Focodyn) which measures the surface roughness.
A stylus has a pseudoconical shape with a hemispherical tip. Typical sizes for the tip are 2, 5, or 10 μm. The selection of the stylus
tip is dependent on the range of the roughness measured.
3.2 Total Hip Joint Prosthesis:
3.2.1 Femoral Head:
3.2.1.1 When inspected visually under a 5-diopter magnification, the metal bearing surface shall be free from particles, scratches,
and score marks other than those arising from the finishing process.within the specifications of the manufacturing process. Ceramic
bearing surfaces need to be inspected visually only under a 3.5-diopter magnifying glass. Since lighting is an important factor in
this inspection the lighting conditions shall be stable and repeatable.
3.2.1.2 sphericity—The metal or ceramic spherical bearing surface of a femoral hip component used in conjunction with a
polyethylene acetabular component shall have a departure from roundness of not greater than 10 μm (390(~390 μin.) This shall
be measured as ΔZ in accordance with the Minimum Zone Center Method in ISO 4291 measuring the roundness in more than
z
two planes, or by the method in Appendix X2. For metallic femoral heads used in conjunction with metallic acetabular components
and ceramic femoral heads used in conjunction with ceramic acetabular components, the departure from roundness values shall
not be greater than 5 μm (200 μin.).(~200 μin.). Alternatively, the departure from surface profile can be used for the characterization
of sphericity. This shall be measured in accordance with ISO 7206-2, by use of the scanning technique described in A.1. In such
a case, the metal or ceramic spherical bearing surface of the femoral hip component shall have a departure from surface profile
of not greater than 10 μm (~390 μin.) when used in conjunction with a polyethylene acetabular component; or 5 μm (~200 μin.)
when used in a metal-on-metal or ceramic-on-ceramic system respectively, as specified above.
3.2.1.3 surface finish—When measured in accordance with ANSI/ASMEASME B46.1, the spherical bearing surface of a metallic
femoral component shall have a R value not greater than 0.05 μm (2 μin.) and the spherical bearing surface of a ceramic femoral
a
component shall have a R value not greater than 0.02 μm (0.8 μin.). The measurements shall be taken at the location of the pole
a
and 30° from the pole.
3.2.1.4 dimensional tolerances—The spherical bearing surface shall have a diameter equal to the nominal diameter with a
tolerance of +0.0, −0.2–0.2 mm (+0.000, −0.008 in.)–0.008 in.).
3.2.1.5 For metallic femoral heads used in conjunction with metallic acetabular components, or ceramic femoral heads used in
conjunction with ceramic acetabular components, the manufacturer should report the diameters and tolerances of the heads, if
different from the tolerance values in 3.2.1.4.
3.2.2 Polymeric Acetabular Components:
3.2.2.1 When inspected visually under 5-diopter magnification, the bearing surface shall be free from particles, scratches, and
score marks other than those arising from the finishing process.within the specifications of the manufacturing process. Since
lighting is an important factor in this inspection the lighting conditions shall be stable and repeatable.
3.2.2.2 surface finish—When measured in accordance with ANSI/ASMEASME B46.1, the spherical bearing surface of the
acetabular component shall have a R value not greater than 2 μm (80 μin.)μin.).
a
3.2.2.3 dimensional tolerances—The spherical socket shall have a diameter equal to the nominal diameter within a tolerance of
+0.3, −0.0–0.0 mm (+0.012, −0.0–0.0 in) at a temperature of 20 6 2°C2 °C (68 6 4°F).4 °F). The socket should be oversized to
the nominal within the given tolerance range.
3.2.3 Metallic Acetabular Components:
3.2.3.1 When inspected visually under 5-diopter magnification, the bearing surface shall be free from particles, scratches, and
score marks other than those arising from the finishing process.within the specifications of the manufacturing process. Since
lighting is an important factor in this inspection the lighting conditions shall be stable and repeatable.
3.2.3.2 sphericity—The spherical bearing surface of the metal acetabular component shall have a departure from roundness of not
F2033 − 20
greater than 15 μm (590 μin.). This shall be measured as ΔZ in accordance with the Minimum Zone Center Method in ISO 4291
z
measuring the roundness in more than two places, or as determined by the method in Appendix X2.
3.2.3.3 surface finish—When measured in accordance with ANSI/ASMEASME B46.1, the spherical bearing surface of the
acetabular component shall have a R value of not greater than 0.05 μm (2 μin.).
a
3.2.3.4 Diametral clearance values shall be as follows: for head diameters of 28 to 36 mm, the clearance between the articulating
part of the socket and metallic head, when both components are at maximum material condition (MMC), shall never be less than
40 μm. When both components are at least material condition (LMC) the clearance shall never be larger than 190 μm. For head
diameters larger than 36 mm, the MMC clearances shall never be less than 70 μm or the LMC clearances greater than 360 μm.
3.2.3.5 Metallic heads and sockets from different manufacturers should not be mated because the combinations of tolerances
within the family, surface finish, and configuration for the different manufacturers may not have been validated through appropriate
testing.
3.2.4 Ceramic Acetabular Components:
3.2.4.1 When inspected visually under 5-diopter3.5-diopter magnification, the bearing surface shall be free from particles,
scratches, and score marks other than those arising from the finishing process.within the specifications of the manufacturing
process. Since lighting is an important factor in this inspection the lighting conditions shall be stable and repeatable.
3.2.4.2 sphericity—The ceramic spherical bearing surface of aan acetabular component shall have a departure from roundness of
not greater than 5 μm (200(~200 μin.). This shall be measured as ΔZ in accordance with the Minimum Zone Center Method in
z
ISO 4291, measuring the roundness in more than two planes, or as determined by the method in Appendix X2. Alternatively, the
departure from surface profile can be used for characterization of sphericity. In this case, the bearing surface shall have a departure
from surface profile of not greater than 7 μm (275 μin). This shall be measured in accordance with ISO 7206-2, by use of the
scanning technique described in A.2.
3.2.4.3 surface finish—When measured in accordance with ANSI/ASMEASME B46.1, the spherical bearing surface of the
acetabular component shall have a R value of not greater than 0.05 μm (2 μin.).
a
3.2.4.4 Under MMC, the articulating part of the socket and ceramic head, there should be clearance and both components never
produce an interference fit.
3.2.4.5 Ceramic heads and sockets from different manufacturers should not be mated because the combinations of tolerances
within the family, surface finish, and configuration for the different manufacturers may not have been validated through appropriate
testing.
3.3 Hip Endoprostheses:
3.3.1
...