FprEN ISO 10328

• Abstract:

  IMPORTANT - ISO 10328:2016 is suitable for the assessment of the conformity of lower limb prosthetic devices/structures with the strength requirements specified in 4.4 of ISO 22523:2006 (see NOTE 1). Prosthetic ankle-foot devices and foot units on the market, which have demonstrated their compliance with the strength requirements specified in 4.4 of ISO 22523:2006 through submission to the relevant tests of ISO 10328:2006, need not be retested to ISO 22675:2016.; WARNING - ISO 10328:2016 is not suitable to serve as a guide for the selection of a specific lower limb prosthetic device/structure in the prescription of an individual lower limb prosthesis! Any disregard of this warning can result in a safety risk for amputees.; ISO 10328:2016 specifies procedures for static and cyclic strength tests on lower-limb prostheses (see NOTE 2) which typically produce compound loadings by the application of a single test force. The compound loads in the test sample relate to the peak values of the components of loading which normally occur at different instants during the stance phase of walking.

• Status: Not Published
• Publication Date: 03-Jan-2027
• ICS: 11.040.40 - Implants for surgery, prosthetics and orthotics
• ICS: 11.180.10 - Aids and adaptation for moving
• Technical Committee: CEN/TC 293 - Technical aids for disabled persons
• Current Stage: 5060 - Closure of Vote - Formal Approval
• Start Date: 02-Oct-2026
• Completion Date: 02-Oct-2026
• Directive: 2017/745 - Regulation (EU) 2017/745 of the European Parliament and of the Council of 5 April 2017 on medical devices, amending Directive 2001/83/EC, Regulation (EC) No 178/2002 and Regulation (EC) No 1223/2009 and repealing Council Directives 90/385/EEC and 93/42/EEC
• Mandate: M/575 - Medical devices in support of Regulation (EU) 2017/745 and in vitro diagnostic medical devices in support of Regulation (EU) 2017/746
• Mandate: M/575 AMD 2 - Medical devices in support of Regulation (EU) 2017/745 and in vitro diagnostic medicial devices in support of Regulation (EU) 2017746
• Ref Project: kSIST FprEN ISO 10328:2026 - Prosthetics - Structural testing of lower-limb prostheses - Requirements and test methods (ISO/FDIS 10328:2026)

• Consolidated By: ISO 10328 - Prosthetics — Structural testing of lower-limb prostheses — Requirements and test methods
• Effective Date: 12-Feb-2026
• Revises: EN ISO 10328:2016 - Prosthetics - Structural testing of lower-limb prostheses - Requirements and test methods (ISO 10328:2016)
• Effective Date: 03-May-2023

FprEN ISO 10328 is a CEN draft European standard for structural testing of lower-limb prostheses. It specifies static and cyclic strength test methods, test loading levels, sample preparation, and reporting for manufacturers, test laboratories, and submitters who need to assess prosthetic devices, structures, and components.

What does FprEN ISO 10328 specify?

FprEN ISO 10328 specifies how to test the strength of lower-limb prostheses under repeatable static and cyclic loading. It is written for complete structures, partial structures, and individual components, but it is not a guide for prescribing a specific device to an individual amputee.

The document applies to ankle-disarticulation prostheses with foot components from the normal production line, transtibial prostheses, knee-disarticulation prostheses, transfemoral prostheses, and the distal part of hip-disarticulation and hemi-pelvectomy prostheses. It also limits the test geometry to use up to 150 mm above the knee-joint centre, which matters because the loading setup is only intended for that structural range.

The main body is organized as follows:

• Clauses 1 to 3 cover scope, normative references, and terms.
• Clause 5 sets the strength categories and the intended-use conditions.
• Clauses 6 to 8 define the coordinate systems, loading conditions, loading levels, and numerical test data.
• Clauses 9 to 12 cover compliance, sample selection, responsibility, and the test submission document.
• Clauses 13 to 15 cover equipment, accuracy, and test principles.
• Clauses 16 and 17 give the principal and separate test procedures.
• Clauses 18 to 21 cover logs, test reports, classification, designation, and compliance marking.

Annex	What it covers
Annex A	Internal loads and their effects
Annex B	Reference data, test loading conditions, and formulas for principal cyclic tests
Annex C	Guidance on an alternative static ultimate strength test
Annex D	Summary of records for the test laboratory/facility log
Annex E	Loading profiles used for ankle-foot device and foot unit cyclic testing
Annex G	Additional lower test loading level P2
Annex H	Alternative test geometry for loading conditions I and II
Annex ZA	Relationship with Regulation (EU) 2017/745 and presumption of conformity

What are the key requirements of FprEN ISO 10328?

FprEN ISO 10328 requires the manufacturer or submitter to assign a Test Range (R) from the written intended use of the device, then test the device at the matching loading level and body mass limit. In practice, that means the test setup must match how the prosthesis is meant to be used, not just its nominal type.

Strength categories and intended use

Clause 5 and Table 2 define the main strength categories:

• Proof strength - the structure must sustain prescribed static loading and stay within limits for permanent deformation.
• Ultimate strength - the structure must withstand higher static loading, even if it is no longer usable afterward.
• Fatigue strength - the structure must survive repeated loading for a prescribed number of cycles, followed by a final static load.
• Static strength in torsion - the structure must sustain a static twisting load for a prescribed time.
• Security against slippage of clamped components - the joints and clamps must not slip beyond the stated limit.

This matters because the standard separates safe use, permanent deformation, failure under overload, and repeated-use durability.

Clause 5.2 adds a safety concept: the device or structure shall meet the relevant compliance clauses, be used within the manufacturer’s body mass limit, and be used only for the intended use stated in the instructions. That is the practical link between the laboratory result and the product’s permitted real-world use.

Coordinate systems and loading geometry

Clauses 6 and 7 define right- and left-sided coordinate systems, the reference planes T, K, A, and B, the load line, and the reference points where the force is applied. These definitions matter because the test forces are not arbitrary - they are positioned to generate compound internal loads in a controlled way.

The document uses offsets, lever arms, and effective joint centres and centrelines to place the sample correctly. For a lab, this is the core alignment step: if the geometry is wrong, the resulting bending and twisting loads are not the intended ones.

Principal and separate test procedures

Clause 16 covers the principal structural tests:

• principal static proof test
• principal static ultimate strength test
• principal cyclic test, followed by a final static test

Clause 17 covers separate tests:

• static test in torsion for all components
• static proof, static ultimate strength, and cyclic tests for ankle-foot devices and foot units
• static ultimate strength test in maximum knee flexion for knee joints and associated parts
• optional separate tests on knee locks

This split matters because different prosthetic parts fail in different ways, so a complete prosthesis, an ankle-foot device, and a knee lock do not all need the same test sequence.

Test loading levels and data

Clause 8 and the tables in the main body set the test forces, twisting moments, segment lengths, offsets, angles, and cycle counts. The principal loading levels in the main body cover P3 to P8, and Annex G adds P2 for lower loading, which is relevant where smaller users would otherwise require a prosthesis that is too heavy.

The cyclic test uses prescribed loading ranges and prescribed numbers of cycles, and the final static test checks the sample after cyclic loading. For the user of the standard, that means the product must pass both repeated-use loading and a last static check.

Static ultimate loading rate

Annex C explains that the static ultimate strength tests use a loading rate between 100 N/s and 10 kN/s. This is important in practice because the loading rate can affect how some non-metallic materials respond, so the laboratory must select and document the rate within that normative range.

Compliance, samples, and re-use

Clauses 9 and 10 require the tests to be run on a prescribed number of samples from the allowed batch, with the sample in the worst-case alignment and, where relevant, the most adverse prosthetic assembly possible. The document also allows re-use of samples in some cases, but only under the stated restrictions and with re-alignment.

That means compliance is not based on a single convenient setup. The laboratory must test a deliberately adverse setup, and the report must state the test loading level and Test Range (R) used.

What terms does FprEN ISO 10328 define?

FprEN ISO 10328 defines the key strength terms it uses so that test reports and compliance claims are consistent.

• Proof strength - a static load representing an occasional severe event that the device can sustain and still function as intended.
• Ultimate strength - a static load representing a gross single event that the device can sustain, although it could become unusable afterward.
• Fatigue strength - a cyclic load that the device can sustain for a given number of cycles.
• Batch - the set of test samples submitted together to a laboratory or facility for conformity testing.
• Shock absorption capacity - the specimen’s ability to absorb energy by deflection without a proportional increase in force.
• Force applied to a sample under test - the load that is applied to the specimen during the test.
• Test Range (R) - the loading range assigned from the written intended use and used to select the appropriate test loading level.

Who uses FprEN ISO 10328?

FprEN ISO 10328 is used by prosthetic manufacturers, component suppliers, test laboratories, and submitters who need to demonstrate structural performance. It is also used by quality, regulatory, and product verification teams who must decide which tests to run, how to set up the samples, and how to document the results.

In practice, users rely on it to prepare test samples, choose the correct alignment and loading level, run proof, ultimate, cyclic, and torsion tests, and prepare the test log and report. It is particularly relevant when a prosthetic design includes ankle-foot devices, foot units, knee joints, or knee locks.

What changed in FprEN ISO 10328 from the previous edition?

FprEN ISO 10328 reflects several updates described in the document itself. Annex C makes the loading rate for the static ultimate strength tests normative at 100 N/s to 10 kN/s, Annex G adds a lower loading level P2, and Annex H provides an alternative test geometry for loading conditions I and II as guidance.

Annex B also explains that the current loading-level designations P5, P4, and P3 correspond to former A100, A80, and A60 designations. This matters because older references may use the earlier names, while the current document uses the P-level system for classification and identification.

Which standards are used with FprEN ISO 10328?

FprEN ISO 10328 cites several standards in Clause 2:

• ISO 7000 - provides registered graphical symbols for equipment and supports the identifier layout.
• ISO 8549-1 - provides vocabulary for external limb prostheses and external orthoses.
• ISO 22675:2024 - provides requirements and test methods for ankle-foot devices and foot units.
• ISO 22523:2006 - provides requirements and test methods for external limb prostheses and external orthoses, including the strength context referenced by this document.
• IEC 60417 - provides graphical symbols for equipment.

Annex ZA also maps the standard to Regulation (EU) 2017/745 and lists these supporting standards for presumption of conformity in the European medical-device context.

What does the FprEN ISO 10328 document contain?

FprEN ISO 10328 contains the drawings, tables, formulas, and step-by-step procedures needed to set up and run the tests. It includes coordinate-system figures, load-line and reference-plane definitions, tables of loads and cycles, and the formulas used to derive internal forces, moments, offsets, and lever arms.

It also contains flowchart-based procedures for the principal static, cyclic, torsion, ankle-foot device, foot unit, and maximum knee flexion tests. The annexes provide background data, alternative loading profiles, logging guidance, an alternative geometry, and an additional lower loading level.

For laboratories and manufacturers, the document is therefore not just a list of pass/fail criteria. It is a complete test framework for preparing samples, applying loads, recording results, writing reports, and classifying compliant lower-limb prosthetic structures.

SLOVENSKI STANDARD
oSIST prEN ISO 10328:2025
01-september-2025
Protetika - Preskušanje strukture protez spodnjih okončin - Zahteve in preskusne
metode (ISO/DIS 10328:2025)
Prosthetics - Structural testing of lower-limb prostheses - Requirements and test
methods (ISO/DIS 10328:2025)
Prothetik - Prüfung der Struktur von Prothesen der unteren Gliedmaßen - Anforderungen
und Prüfverfahren (ISO/DIS 10328:2025)
Prothèses - Essais portant sur la structure des prothèses de membres inférieurs -
Exigences et méthodes d'essai (ISO/DIS 10328:2025)
Ta slovenski standard je istoveten z: prEN ISO 10328
ICS:
11.040.40 Implantanti za kirurgijo, Implants for surgery,
protetiko in ortetiko prosthetics and orthotics
oSIST prEN ISO 10328:2025 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 10328:2025
oSIST prEN ISO 10328:2025
DRAFT
International
Standard
ISO/DIS 10328
ISO/TC 168
Prosthetics — Structural testing
Secretariat: DIN
of lower-limb prostheses —
Voting begins on:
Requirements and test methods
2025-06-17
Prothèses — Essais portant sur la structure des prothèses de
Voting terminates on:
membres inférieurs — Exigences et méthodes d'essai
2025-09-09
ICS: 11.040.40
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
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Reference number
ISO/DIS 10328:2025(en)
oSIST prEN ISO 10328:2025
DRAFT
ISO/DIS 10328:2025(en)
International
Standard
ISO/DIS 10328
ISO/TC 168
Prosthetics — Structural testing
Secretariat: DIN
of lower-limb prostheses —
Voting begins on:
Requirements and test methods
Prothèses — Essais portant sur la structure des prothèses de
Voting terminates on:
membres inférieurs — Exigences et méthodes d'essai
ICS: 11.040.40
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
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BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
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Published in Switzerland Reference number
ISO/DIS 10328:2025(en)
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Contents Page
Foreword .vii
Introduction .ix
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 2
4 Symbols . 2
5 Strength and related performance requirements and conditions of use . 3
6 Coordinate systems and test configurations . 4
6.1 General .4
6.2 Axes of coordinate systems.5
6.3 Reference planes .5
6.3.1 General .5
6.3.2 Top reference plane, T.5
6.3.3 Knee reference plane, K .5
6.3.4 Ankle reference plane, A .5
6.3.5 Bottom reference plane, B . .6
6.4 Reference points.8
6.5 Test force . .8
6.6 Load line .8
6.7 Longitudinal axis of the foot and effective joint centres and centrelines .8
6.7.1 General .8
6.7.2 Longitudinal axis of the foot .8
6.7.3 Effective ankle-joint centre .8
6.7.4 Effective ankle-joint centreline .10
6.7.5 Effective knee-joint centreline . .10
6.7.6 Effective knee-joint centre .11
6.8 Reference distances .11
6.8.1 Offsets .11
6.8.2 Combined offsets . 12
6.8.3 Effective lever arms L and L . 12
A K
6.8.4 Distance L . 12
BT
7 Test loading conditions and test loading levels .12
7.1 Test loading conditions . 12
7.1.1 General . 12
7.1.2 Test loading conditions of principal structural tests . 12
7.1.3 Test loading conditions of separate structural tests . 13
7.2 Test loading levels and Test Ranges (R) . 13
8 Values of test loads, dimensions and cycles . 14
9 Compliance .20
9.1 General . 20
9.2 Selection of tests required to claim compliance with this document . 20
9.3 Arrangements for tests on samples of prosthetic structures including ankle-foot
devices or foot units, required to claim compliance with this document . 20
9.3.1 General . 20
9.3.2 Particular arrangements concerning the ankle-foot device or foot unit . 20
9.3.3 Particular arrangements and requirements concerning the part required to
connect the ankle-foot device or foot unit to the remainder of the prosthetic
structure .21
9.4 Number of tests and test samples required to claim compliance with this document .21
9.5 Multiple use of test samples . .21
9.5.1 General .21

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9.5.2 Restriction . 22
9.6 Testing at particular test loading levels not specified in this document . 22
10 Test samples .24
10.1 Selection of test samples .24
10.1.1 General .24
10.1.2 Selection of ankle-foot devices and foot units of appropriate size of foot . 25
10.2 Types of test samples . 25
10.2.1 Complete structure . 25
10.2.2 Partial structure . 28
10.2.3 Any other structure . 28
10.3 Preparation of test samples . 28
10.4 Identification of test samples . 29
10.5 Alignment of test samples . 30
10.5.1 Test samples for principal tests and optional separate tests on knee locks . 30
10.5.2 Test samples for separate tests on ankle-foot devices and foot units . 30
10.5.3 Test samples for separate static ultimate strength tests in maximum knee
flexion for knee joints and associated parts . 30
10.6 Worst-case alignment position of test samples .31
11 Responsibility for test preparation .32
12 Test submission document . .33
12.1 General requirements . 33
12.2 Information required for test samples . 34
12.2.1 All test samples . 34
12.2.2 Test samples for tests on ankle-foot devices and foot units . 34
12.2.3 Test samples for static ultimate strength tests in maximum knee flexion for
knee joints and associated parts . 34
12.3 Information required for tests . 34
12.3.1 General . 34
12.3.2 For all tests . 34
12.3.3 For static tests in torsion and on ankle-foot devices and foot units . 35
12.3.4 For static ultimate strength tests . 35
12.3.5 For cyclic tests . 35
12.3.6 For tests in torsion . 35
12.3.7 For tests on ankle-foot devices and foot units . 35
13 Equipment .35
13.1 General . 35
13.2 Equipment for the principal tests specified in 16.2 and 16.3 . 36
13.2.1 End attachments . 36
13.2.2 Jig (optional) . 38
13.2.3 Test equipment . 38
13.3 Equipment for the separate static test in torsion specified in 17.1 . 40
13.3.1 Test equipment . 40
13.4 Equipment for the separate tests on ankle-foot devices and foot units specified in 17.2 . 40
13.4.1 Test equipment . 40
13.5 Equipment for the separate static ultimate strength test in maximum knee flexion for
knee joints and associated parts specified in 17.3 . 44
13.5.1 Extension pieces . 44
13.5.2 Test equipment to perform static compression loading – (Compression testing
machine or other equipment) . 44
13.6 Equipment for the optional separate tests on knee locks specified in 17.4 . 44
13.6.1 End attachments . 44
14 Accuracy .44
14.1 General . 44
14.2 Accuracy of equipment .45
14.3 Accuracy of procedure .45
15 Test principles .45

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15.1 General .45
15.2 Static test procedure .45
15.3 Cyclic test procedure . 49
16 Test procedures – Principal structural tests .49
16.1 Test loading requirements . 49
16.1.1 Preparation for test loading . 49
16.1.2 Application of test loading . 50
16.2 Principal static test procedure . .51
16.2.1 Principal static proof test .51
16.2.2 Principal static ultimate strength test . 56
16.3 Principal cyclic test procedure . 58
16.3.1 General requirements . 58
16.3.2 Test method .59
16.3.3 Performance requirements . . 63
16.3.4 Compliance conditions . 63
17 Test procedures — Separate structural tests . 67
17.1 Separate static test in torsion .67
17.1.1 General .67
17.1.2 Purpose of test .67
17.1.3 Test method .67
17.1.4 Performance requirements . . 69
17.1.5 Compliance conditions . 69
17.2 Separate tests on ankle-foot devices and foot units .71
17.2.1 General .71
17.2.2 Purpose of tests .71
17.2.3 Separate static proof test for ankle-foot devices and foot units .71
17.2.4 Separate static ultimate strength test for ankle-foot devices and foot units . 75
17.2.5 Separate cyclic test for ankle-foot devices and foot units . 78
17.3 Separate static ultimate strength test in maximum knee flexion for knee joints and
associated parts . 84
17.3.1 General . 84
17.3.2 Purpose of test . 84
17.3.3 Applicability of the test to specific test samples. 84
17.3.4 Test method . 85
17.3.5 Performance requirement . 86
17.3.6 Compliance conditions . 86
17.4 Separate optional tests on knee locks . 87
17.4.1 General . 87
17.4.2 Purpose of tests . 87
18 Test laboratory/facility log .87
18.1 General requirements . 87
18.2 Specific requirements . 87
19 Test report .87
19.1 General requirements . 87
19.2 Specific requirements . 88
19.3 Options. 88
20 Classification and designation .88
20.1 General . 88
20.2 Examples of classification and designation . 89
21 Compliance with this document .89
21.1 General . 89
21.2 Example of identifier layout . 89
21.3 Identifier placement . 90
Annex A (informative) Description of internal loads and their effects .91

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Annex B (informative) Reference data for the specification of test loading conditions and test
loading levels and Test Ranges (R) of principal cyclic tests .95
Annex C (informative) Guidance on the application of an alternative static ultimate strength
test .99
Annex D (informative) Summary of the records to be entered in the test laboratory/facility log .100
Annex E (informative) Background information on the loading profiles generated by test
equipment according to 13.4.1.2 for separate cyclic tests for ankle-foot devices and foot
units according to 17.2.5.1 .110
Annex F (informative) Background Data (reduced) of the six-minute walk test for Adults
(see [5]) .112
Annex G (informative) Guidance on the application of an additional test loading level P2 .113
Annex H (informative) Alternative test geometry for loading condition I and II derived from
recent biomechanical studies .118
Annex ZA (informative) Relationship between this European standard and the General Safety
and Performance Requirements of Regulation (EU) 2017/745 aimed to be covered .120
Bibliography .123

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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of patent.
ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights in respect
thereof. As of the date of publication of this document, ISO had not received notice of patents which may be
required to implement this document. However, implementers are cautioned that this may not represent the
latest information, which may be obtained from the patent database available at www.iso.org/patents. ISO
shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 168, Prosthetics and orthotics.
This third edition cancels and replaces the second edition (ISO 10328:2016), which has been technically
revised.
The main changes are as follows:
— Offsets for P3 and P4 are combined into the test offset for P5 in Table 7 and have been removed from
document. Outward offset at bottom reference plane has been changed from -19 mm to +19 mm to align
with results from modern gait analysis. Outwards offsets knee and ankle have been adjusted accordingly.
— Test load levels P6 through P8 previously in former Annex D have been included in Tables 5, 9 and 12 and
the Annex removed from the document. Former Annex E and F have been renamed to Annex D and E and
references updated. Former Annex G has been removed. New Annex F, Annex G, Annex H and Annex ZA
have been added.
— Test Ranges (R) for the strength test have been introduced, related to the intended use of the device. The
ranges differ by different loading factors, while tests load levels remain unchanged apart from rounding
and accommodation to changed offsets (see below).
— Test forces in Table 12 have been adjusted for P3 and P4.
— A method to analyse shock absorption capacity has been added, which eliminates the difficulty to decide
whether a device passes or fails above the ultimate static lower load level.
— Separate tests on knee locks are now optional tests and the test methods on separate tests on knee locks
have been removed from the document.
— Test geometry of this document is limited to 150mm above knee-joint centre.
— Section 21 has been renamed to Compliance to Standard and reference to Labelling has been removed
from the document.
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— Table 2, Table 5, Table 6, Table 7, Table 8, Table 9, Table 10, Table 11 and Table 12 have been updated and
forces adjusted for new unified offsets.
— Table B.1, Table B.2, Table B.3 and Table B.4 have been updated.
— The rate of loading of between 100 N/s and 10 kN/s is now normative.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

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Introduction
Throughout this document, the term prosthesis means an externally applied device used to replace wholly,
or in part, an absent limb segment.
As a result of concern in the international community about the need to provide prostheses that are safe in
use, and also because of an awareness that test standards would assist the development of better prostheses,
a series of meetings was held under the aegis of the International Society for Prosthetics and Orthotics
(ISPO). The final one was held in Philadelphia, PA, USA in 1977 at which a preliminary consensus was
reached on methods of testing and the required load values. From 1979 onwards this work was continued by
ISO Technical Committee 168 leading to the development of ISO 10328:1996. The test procedures may not be
applicable to prostheses of mechanical characteristics different from those used in the consensus.
During use, a prosthesis is subjected to a series of load actions, each varying individually with time. The test
methods specified in this document use static and cyclic strength tests which typically produce compound
loadings by the application of a single test force.
The static tests relate to the worst loads generated in any activity. The cyclic tests relate to normal walking
activities where loads occur regularly with each step. This document specifies fatigue testing of structural
components. The tests specified do not provide sufficient data to predict actual service life.
The evaluation of lower-limb prostheses and their components requires controlled field trials in addition to
the laboratory tests specified in this document.
The laboratory tests and field trials should be repeated when significant design changes are made to a load-
bearing part of a prosthesis.
Ideally, additional laboratory tests should be carried out to deal with function, wear and tear, new material
developments, environmental influences and user activities as part of the evaluation procedure. There are
no standards for such tests, so appropriate procedures will need to be determined.

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oSIST prEN ISO 10328:2025
oSIST prEN ISO 10328:2025
DRAFT International Standard ISO/DIS 10328:2025(en)
Prosthetics — Structural testing of lower-limb prostheses —
Requirements and test methods
1 Scope
WARNING — This document is not suitable to serve as a guide for the selection of a specific lower
limb prosthetic device/structure in the prescription of an individual lower limb prosthesis! Any
disregard of this warning can result in a safety risk for amputees.
This document specifies procedures for static and cyclic strength tests on lower-limb prostheses (see NOTE
2) which typically produce compound loadings by the application of a single test force. The compound loads
in the test sample relate to the peak values of the components of loading which normally occur at different
instants during the stance phase of walking.
This document specifies Test Ranges (R) by specifying locomotion profiles for the cyclic test in relation to
the intended use. According to the concept of the tests of this document, each sample of lower limb prosthetic
device / structure submitted for test is, nevertheless, free to develop its individual performance under load.
The tests desc
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