ASTM F384-17

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.
Designation: F384 − 17
Standard Specifications and Test Methods for
Metallic Angled Orthopedic Fracture Fixation Devices
This standard is issued under the fixed designation F384; 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.
NOTE 2—There is currently no ISO standard that is either similar to
1. Scope
equivalent to this standard.
1.1 These specifications and test methods provide a com-
1.6 Multiple test methods are included in this standard.
prehensive reference for angled devices used in the surgical
However, the user is not necessarily obligated to test using all
internal fixation of the skeletal system. This standard estab-
of the described methods. Instead, the user should only select,
lishes consistent methods to classify and define the geometric
with justification, test methods that are appropriate for a
and performance characteristics of angled devices. This stan-
particular device design. This may be only a subset of the
dard also presents a catalog of standard specifications that
herein described test methods.
specify material, labeling, and handling requirements, and
1.7 This international standard was developed in accor-
standard test methods for measuring performance related
dance with internationally recognized principles on standard-
mechanical characteristics determined to be important to the in
ization established in the Decision on Principles for the
vivo performance of angled devices.
Development of International Standards, Guides and Recom-
1.2 It is not the intention of this standard to define levels of
mendations issued by the World Trade Organization Technical
performance or case-specific clinical performance for angled
Barriers to Trade (TBT) Committee.
devices, as insufficient knowledge is available to predict the
consequences of their use in individual patients for specific
2. Referenced Documents
activities of daily living. Futhermore, this standard does not
2.1 ASTM Standards:
describe or specify specific designs for angled devices used in
E4 Practices for Force Calibration and Verification of Test-
the surgical internal fixation of the skeletal system.
ing Machines
1.3 This standard may not be appropriate for all types of
E8 Test Methods for Tension Testing of Metallic Materials
angled devices. The user is cautioned to consider the appro-
[Metric] E0008_E0008M
priateness of this standard in view of a particular angled device
E122 Practice for Calculating Sample Size to Estimate, With
and its potential application.
Specified Precision, the Average for a Characteristic of a
NOTE 1—This standard is not intended to address intramedullary hip
Lot or Process
screw nails or other angled devices without a sideplate.
F67 Specification for Unalloyed Titanium, for Surgical Im-
1.4 This standard includes the following test methods used
plant Applications (UNS R50250, UNS R50400, UNS
in determining the following angled device mechanical perfor-
R50550, UNS R50700)
mance characteristics:
F75 Specification for Cobalt-28 Chromium-6 Molybdenum
1.4.1 Standard test method for single cycle compression
Alloy Castings and Casting Alloy for Surgical Implants
bend testing of metallic angled orthopedic fracture fixation
(UNS R30075)
devices (see Annex A1).
F90 Specification for Wrought Cobalt-20Chromium-
1.4.2 Standard test method for determining the bending
15Tungsten-10Nickel Alloy for Surgical Implant Applica-
fatigue properties of metallic angled orthopedic fracture fixa-
tions (UNS R30605)
tion devices (see Annex A2).
F136 Specification for Wrought Titanium-6Aluminum-
1.5 The values stated in SI units are to be regarded as 4Vanadium ELI (Extra Low Interstitial) Alloy for Surgical
standard. No other units of measurement are included in this Implant Applications (UNS R56401)
standard. F138 Specification for Wrought 18Chromium-14Nickel-
2.5Molybdenum Stainless Steel Bar and Wire for Surgical
Implants (UNS S31673)
These specifications and test methods are under the jurisdiction of ASTM
Committee F04 on Medical and Surgical Materials and Devices and are the direct
responsibility of Subcommittee F04.21 on Osteosynthesis. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Feb. 1, 2017. Published March 2017. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1973. Last previous edition approved in 2012 as F384 – 12. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/F0384-17. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F384 − 17
FIG. 1 Diagram Illustrating Compression Hip Screw Angled Devices
F139 Specification for Wrought 18Chromium-14Nickel- ISO 9269 Implants for Surgery—Metal Bone Plates—Holes
2.5Molybdenum Stainless Steel Sheet and Strip for Sur- and Slots corresponding to Screws with Conical Under-
gical Implants (UNS S31673) Surface
F382 Specification and Test Method for Metallic Bone Plates ISO 14602 Non-active Surgical Implants—Implants for
F565 Practice for Care and Handling of Orthopedic Implants Osteosynthesis—Particular Requirements
and Instruments
F620 Specification for Titanium Alloy Forgings for Surgical 3. Terminology
Implants in the Alpha Plus Beta Condition
3.1 Definitions: Geometric
F621 Specification for Stainless Steel Forgings for Surgical
3.1.1 angle (degree)—defined at either the barrel/sideplate
Implants
or blade/sideplate junction (see Fig. 1 and Fig. 2).
F983 Practice for Permanent Marking of Orthopaedic Im-
3.1.2 angled device—an orthopaedic device for the fixation
plant Components
of fractures in the metaphyseal areas of long bones that has a
F1295 Specification for Wrought Titanium-6Aluminum-
component aligned at an angle to the long axis of the bone.
7Niobium Alloy for Surgical Implant Applications (UNS
R56700)
3.1.3 barrel—the portion of an angled device which cap-
F1314 Specification for Wrought Nitrogen Strengthened 22
tures the lag screw (see Fig. 1).
Chromium–13 Nickel–5 Manganese–2.5 Molybdenum
3.1.4 barrel length, L (mm)—the distance from the free
BR
Stainless Steel Alloy Bar and Wire for Surgical Implants
end of the barrel to the interior vertex of the barrel/sideplate
(UNS S20910)
junction (see Fig. 1).
F1472 Specification for Wrought Titanium-6Aluminum-
4Vanadium Alloy for Surgical Implant Applications (UNS 3.1.5 blade—the portion of an angled device which trans-
R56400) mits the off axis loading of the anatomical loading condition to
the sideplate portion of the angled device (see Fig. 2).
F1713 Specification for Wrought Titanium-13Niobium-
13Zirconium Alloy for Surgical Implant Applications
3.1.6 blade length, L (mm)—the distance from the free
BD
(UNS R58130)
end of the blade to the interior vertex of the blade/sideplate
F2503 Practice for Marking Medical Devices and Other
junction (see Fig. 2).
Items for Safety in the Magnetic Resonance Environment
3.1.7 lag screw—that component of a compression hip
2.2 ISO Standards:
screw angled device which is threaded into the metaphysis and
ISO 5835 Implants for Surgery—Metal Bone Screws with
transmits the off axis load to the sideplate through the barrel
Hexagonal Drive Connection—Spherical Under Surface
(see Fig. 1).
of Head, Asymmetrical Thread
3.1.8 lag screw length (mm)—the straight line distance
ISO 5836 Implants for Surgery—Metal Bone Plates—Holes
corresponding to Screws with Asymmetrical Thread and measured between the proximal and distal ends of the lag
screw (see Fig. 1).
Spherical Under Surface
ISO 9268 Implants for Surgery—Metal Bone Screws with
3.1.9 sideplate—that portion of the angle device generally
Conical Under-Surface of Head—Dimensions
aligned with the long axis of the bone which attaches to the
bone via bone screws (see Fig. 1 and Fig. 2).
3.1.10 sideplate length, L (mm)—the distance from the free
Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
4th Floor, New York, NY 10036, http://www.ansi.org. end of the sideplate to the interior vertex of the barrel/sideplate
F384 − 17
4. Classification
4.1 Angled devices used in general orthopedic surgery
represents a subset of bone plates. Angled devices are mainly
used in the treatment of fractures in the metaphyseal areas of
long bones. Angled devices can be categorized into general
types according to the following classifications:
4.1.1 Blade Plate—an angled device where the component
of the device that is oriented at an angle from the long axis of
the bone is fixed relative to the sideplate; this component often
is shaped like a blade to achieve fixation into the metaphysis
(see Fig. 2), and
4.1.2 Compression Hip Screw—an angled device where the
FIG. 2 Diagram Illustrating Blade Plate Angled Devices
component of the device which is oriented at an angle from the
long axis of the bone is free to translate relative to the sideplate
through a barrel; this component often achieves fixation into
the metaphysis through the use of deep threads (see Fig. 1).
junction or to the interior vertex of the blade/sideplate junction
(see Fig. 1 and Fig. 2).
5. Marking, Packaging, Labeling and Handling
3.1.11 sideplate thickness, b (mm)—the linear dimension of
5.1 Dimensions of angled devices should be designated by
the sideplate measured parallel to the screw hole axis (see Fig.
the standard definitions given in 3.1.
1 and Fig. 2). For a sideplate with a crescent section, the
5.2 Angled devices shall be marked using a method speci-
thickness is measured at the thickest point along the section.
fied in accordance with either Practice F983 or ISO 14602.
3.1.12 sideplate width, w (mm)—the linear dimension of the
5.3 Markings on angled devices shall identify the manufac-
sideplate measured perpendicular to both the length and
ture or distributor and shall be situated away from the most
thickness axes (see Fig. 1 and Fig. 2).
highly stressed areas, where possible.
3.1.13 thread diameter (mm)—the maximum outer diameter
5.4 Packaging shall be adequate to protect the angled device
of the lag screw threads (see Fig. 1).
during shipment.
3.1.14 thread length (mm)—the straight line distance mea-
5.5 Package labeling for angled devices shall include when
sured between the tip and thread runout positions of the screw
possible the following information:
(see Fig. 1).
5.5.1 Manufacturer and product name;
3.2 Definitions:Mechanical/Structure:
5.5.2 Catalog number;
3.2.1 bending strength (N-m)—of the sideplate, the bending 5.5.3 Lot or serial number;
moment necessary to produce a 0.2 % offset displacement in
5.5.4 Material and, where applicable, its associated ASTM
the sideplate when tested as described in Annex A1 of specification designation number;
Specification and Test Method F382.
5.5.5 Device angle, between the sideplate and the barrel
2 (blade);
3.2.2 bending structural stiffness, El (N-m )—of the
e
5.5.6 Barrel (blade) length;
sideplate, the normalized effective bending stiffness of the
5.5.7 Number of screw holes;
sideplate that takes into consideration the test setup configu-
5.5.8 Sideplate width;
ration when tested according to the method described in Annex
5.5.9 Sideplate length;
A1.
5.5.10 Sideplate thickness;
3.2.3 compression bending stiffness, (K) (N/m)—of a device,
5.5.11 Screw hole size; and
the maximum slope of the linear elastic portion of the load
5.5.12 ASTM specification designation number.
versus displacement curve, when tested as described in Annex
5.6 Bone plates should be cared for and handled in accor-
A1.
dance with Practice F565, as appropriate.
3.2.4 compression bending strength (N/m)—of a device, the
5.7 Consider Practice F2503 to identify potential hazards
bending moment necessary to produce a 0.2 % offset displace-
produced by interactions between the device and the MR
ment in the device when tested as described in Annex A1.
environment and for terms that may be used to label the device
3.2.5 fatigue strength at N cycles—an estimate of the cyclic
for safety in the MR environment.
forcing parameter (for example, load, moment, torque, stress,
etc.) at a given load ratio, for which 50 % of the specimens
6. Materials
within a given sample population would be expected to survive
6.1 All angled devices made of materials which can be
N loading cycles.
purchased to an ASTM specification shall meet those require-
3.2.6 fatigue life, N—the number of loading cycles of a ments given in the ASTM specification. Such specification
specified character that a given specimen sustains before include: F67, F75, F90, F139, F1295, F1314, F1472, and
failure of a specified nature occurs. F1713.
F384 − 17
6.2 Angled devices of forged Specification F136 shall meet 7.2.1 The relevant compression bending properties (com-
the requirements of Specification F620. pression bending stiffness and compression bending strength)
of the device shall be determined using Annex A1.
6.3 Angled devices of forged Specification F138 shall meet
7.2.2 The relevant bending properties (bending stiffness,
the requirements of Specification F621.
bending structural stiffness and bending strength) of the
7. General Requirements and Performance
sideplate shall be determined using the Annex A1 of Specifi-
Considerations
cation and Test Method F382.
7.2.3 Determine the relevant angled device bending fatigue
7.1 Geometric Considerations—For angled devices that are
properties according to the methods described in Annex A2.
intended to be used with bone screws that conform to ISO 5835
7.2.4 Determine the relevant side plate bending fatigue
or ISO 9268, the screw holes shall correspond to the dimen-
properties according to the methods described in Annex A1 of
sions and tolerances of ISO 5836 or ISO 9269, respectively.
Specification and Test Method F382.
7.2 Bending Properties—Bending properties are a critical
characteristic of angled devices for orthopedic applications
8. Keywords
since the plate provides the primary means of stabilizing the
bone fragments. Additionally, the bending stiffness of the 8.1 angled devices; bend testing; blade plate; compression
angled device may directly affect the rate and ability of hip screw; fatigue test; orthopedic medical devices; surgical
healing. devices; surgical implants
ANNEXES
(Mandatory Information)
A1. STANDARD TEST METHOD FOR SINGLE CYCLE COMPRESSION BEND TESTING OF METALLIC ANGLED ORTHO-
PEDIC FRACTURE FIXATION DEVICES
A1.1 Scope A1.3 Terminology
A1.1.1 This test method describes methods for single cycle
A1.3.1 Definitions:
bend testing for determining intrinsic, structural properties of
A1.3.1.1 0.2 % offset displacement, q (mm)—permanent
metallic angled orthopedic fracture fixation devices. The test
deformation equal to 0.2 % of the lever arm length (see point
method measures compression bending stiffness and compres-
B in Fig. A1.1).
sion bending strength of the angled device.
A1.3.1.2 compression bending stiffness, K (N/m)—of an
A1.1.2 This test method is intended to provide a means to
angled device, the maximum slope of the linear elastic portion
mechanically characterize different angled device designs. It is
of the load versus displacement curve, when tested as de-
not the intention of this test method to define levels of
scribed in A1.8. (See the slope of line Om in Fig. A1.1).
performance for angled devices, as these characteristics are
A1.3.1.3 compression bending strength (N-m)—of an
driven by patient-specific clinical requirements.
angled device, the bending moment necessary to produce a
A1.1.3 This test method is designed to provide flexibility in
0.2 % offset displacement in the angled device when tested as
the testing configuration so that a range of clinical failure
described in A1.8 (the bending moment corresponding to point
modes for the angled fixation devices (for example, sideplate,
P in Fig. A1.1). If the angled device fractures before the proof
lag screw, and barrel fractures) can be evaluated.
load is attained, the compression bending strength shall be
defined as the bending moment at fracture.
A1.1.4 The values stated in SI units are to be regarded as
A1.3.1.4 fracture load, F (N) —the applied load at the
standard. No other units of measurement are included in this
max
standard. time when the angled device fractures.
A1.3.1.5 lever arm, L (mm)—the instantaneous distance
A1.1.5 This standard does not purport to address all of the
from the line of load application to the surface of the sideplate
safety concerns, if any, associated with its use. It is the
that is intended to be in contact with the bone at the most
responsibility of the user of this standard to establish appro-
proximal location where the sideplate contacts the test fixture
priate safety, health, and environmental practices and deter-
support (shown in Fig. A1.2); the initial unloaded angled
mine the applicability of regulatory limitations prior to use.
device lever arm length shall be held constant for comparative
A1.2 Referenced Documents
tests.
A1.2.1 ASTM Standards: E4 Practices for Load Verifica-
A1.3.1.6 permanent deformation (mm)—the relative change
tion of Testing Machines in the position of the load application point (in the direction of
E122 Practice for Choice of Sample Size to Estimate the the applied load) remaining after the applied load has been
Average Quality of a Lot or Process removed.
F384 − 17
A1.3.1.7 potential critical stress concentrator, CSC—any A1.6 Apparatus
change in section modulus, material property, discontinuity, or
A1.6.1 A typical test configuration is illustrated in Fig.
other feature of an angled device design expected to cause a
A1.1.
concentration of stress, that is located in a region of the angled
A1.6.2 The plate of the angled device being tested is rigidly
device expected to be highly stressed under the normal
attached to an anchor block that is fully constrained. Alterna-
anticipated loading conditions.
tive test setups are allowed (for example, the device support is
A1.3.1.8 proof load, P (N)—the applied load at the intersec-
unconstrained with rollers as allowed by the previous version
tion point of line BC with the load versus total displacement
of this standard) as long as the following conditions are met.
curve (see Fig. A1.1).
A1.6.2.1 The angled device shall be loaded in such a
A1.3.1.9 proof point displacement—the total displacement
manner as to satisfy the goals or requirements of A1.4.1,
associated with the compression bending strength of the angled
A1.5.1, and X2.1.
device (see point A in Fig. A1.1).
A1.6.2.2 If the support of the angled device is allowed to
A1.3.1.10 total displacement (mm)—the relative change in
translate normal to the loading axis of the test machine in
the position of the load application point (in the direction of the
reaction to the applied load during the test, then the lever arm
applied load) when a specified load is applied.
distance shall be monitored during the test. This information
shall then be used to correct the load versus displacement curve
A1.4 Summary of Test Method
(A1.8.2.1) and the compression bending stiffness and strength
A1.4.1 Angled devices are subjected to a single-cycle load
values calculated in A1.8.2.3 and A1.8.2.7, respectively.
introduced at the angled portion of the device. This results in
A1.6.2.3 If the contact point of the loading adapter is
the simultaneous application of compressive and cantilever
allowed to translate normal to the loading axis of the test
bending stresses to the device. The compression bending
machine in reaction to the applied load during the test, then the
stiffness and compression bending strength of the device are
lever arm distance shall be monitored during the test. This
then derived from the record generated during the test using
information shall then be used to correct the load versus
relevant test configuration parameters.
displacement curve (A1.8.2.1) and the compression bending
stiffness and strength values calculated in A1.8.2.3 and
A1.5 Significance and Use
A1.8.2.7, respectively.
A1.5.1 This compression bend test is used to determine
A1.6.3 The applied load should act only parallel to the long
values for the mechanical response of angled devices to a
axis of the sideplate. Apply the load at a point that will produce
specific type of bending load. The information resulting from
a lever arm length that is equivalent to 80 % of either the blade
this test can give the surgeon some insight into the mechanical
length or the longest screw. Equivalent lever arm lengths shall
response of a given angled device.
be used for comparative tests. Deviations to this requirement
A1.5.2 Since the loading on the angled device in situ will, in
shall be noted and justified in the final report. Additionally, the
general, differ from the loading configuration used in this test
application of off axis loads to the load cell shall be avoided
method, the results obtained from this test method cannot be
since, depending on their magnitude, they can confound the
used directly to predict in vivo performance of the angled
determination of the actual loading condition of the device.
device being tested. Such mechanical property data can be used
A1.6.4 The test fixture should, in general, support the
to conduct relative comparisons of different angled device
angled device in such a way as to generate the failure being
designs.
evaluated (sideplate, lag screw, or barrel fracture). A typical
A1.5.3 Since the test method provides flexibility to evaluate
configuration that can be used to evaluate the sideplate failure
a variety of clinical failure modes, the user shall first determine
characteristics of the angled device is illustrated in Fig. A1.2.
which failure mode will be evaluated. Futhermore, the user
A1.6.5 The device being tested should be suitably anchored
should determine the relevance of the failure mode for the
to the support fixture. The intent of the test method is to
angled device being evaluated.
evaluate the angled device and not the sideplate anchors.
A1.5.4 The compression bending stiffness of the angled
A1.6.6 Displacement shall be measured as the displacement
device, as defined in A1.3.1.2, is an indicator of the stiffness of
of the load application point parallel to the long axis of the
the angled device when subjected to a compression-bending
sideplate.
load. This mechanical property is a comparative indicator of
the stability that the user can achieve in the treatment of
A1.6.7 Alternative loading configurations are allowed (1)
metaphyseal fractures with the angled device.
but shall be noted and fully described in the final report.
A1.5.5 The compression bending strength of the angled
A1.6.8 Machines used for the bending test shall conform to
device, as defined in A1.3.1.3, identifies the bending moment
the requirements of Practice E4.
that shall be applied to the angled device in order to produce a
A1.6.9 The test machine and fixtures (test system) should be
specific amount of permanent deformation.
sufficiently stiff that their deformation under the load is
A1.5.6 This test method assumes that linear-elastic material
behavior will be observed and, therefore, the test method is not
applicable for the testing of materials that exhibit non-linear
The boldface numbers in parentheses refer to a list of references at the end of
elastic behavior. this standard.
F384 − 17
negligible relative to that of the angled device being tested. The where:
machine compliance of the test system (combined test machine
L = the lever arm.
and fixture compliance) should be measured and reported.
A1.8.2.5 On the load versus displacement diagram lay off
Typically, the machine compliance of the test system should be
OB equal to q. Then draw line BC parallel to Om.
less than 1 % of the compliance of the tested angled device.
A1.8.2.6 Locate the proof load at the intersection point of
line BC with the load versus displacement curve.
A1.7 Sampling
A1.8.2.7 Calculate the compression bending strength of the
A1.7.1 Determine sample size using the methods outlined in
angled device from the equation:
Practice E122.
compression bending strength 5 P·L (A1.2)
A1.7.2 In those circumstances when there is insufficient
where:
information
...