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: 5020 - Submission to Vote - Formal Approval
• Start Date: 06-Aug-2026
• Completion Date: 06-Aug-2026
• Directive: Harmonized Standard2017/745 - 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: oSIST prEN ISO 10328:2025 - Prosthetics - Structural testing of lower-limb prostheses - Requirements and test methods (ISO/DIS 10328:2025)

• Consolidated By: ISO/FDIS 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

Overview

FprEN ISO 10328: Prosthetics - Structural Testing of Lower-Limb Prostheses - Requirements and Test Methods (ISO/FDIS 10328:2026) sets internationally recognized requirements and methodologies for the structural testing of lower-limb prosthetic devices. Developed by CEN in conjunction with ISO Technical Committee 168, this standard is critical to the assessment of conforming lower-limb prostheses against rigorous strength, safety, and performance benchmarks.

Applicable for conformity assessment as outlined in ISO 22523:2006, FprEN ISO 10328 details specific static and cyclic testing methods to evaluate the structural integrity of prostheses under compound loadings similar to those encountered during walking. The document covers both complete and partial prosthetic structures, including essential subcomponents like ankle-foot devices and knee joints.

Important: This standard is NOT intended to guide prescription or individual selection of prostheses, and misuse may present safety risks to amputees.

Key Topics

• Scope and Applicability

  • Outlines which lower-limb prosthetic devices and subassemblies fall under the standard’s requirements.
  • Clarifies situations where retesting is not mandatory if prior compliance can be demonstrated.

• Testing Requirements

  • Defines static and cyclic test load applications that simulate real-life stresses experienced during walking.
  • Identifies standard test configurations, axes of loading, and reference points for test alignment and reproducibility.

• Test Sample Preparation

  • Specifies criteria for selecting and preparing test samples, including foot and knee subassemblies.
  • Details alignment and worst-case orientation procedures to ensure robust test results.

• Compliance and Reporting

  • Lists the minimum number of samples and test repetitions needed for conformity claims.
  • Provides comprehensive guidelines for test documentation, classification, and reporting to support traceability and regulatory requirements.

• Annexes and Supporting Information

  • Offers additional guidance on alternative test methods, test equipment, background data, and mapping to EU regulation requirements.

Applications

FprEN ISO 10328 is crucial for:

• Manufacturers: Demonstrating that new lower-limb prosthetic designs comply with globally recognized strength and durability criteria before market release.
• Testing Laboratories: Providing standardized methods for evaluating prosthetic integrity, ensuring consistent and comparable results across different facilities.
• Regulatory Bodies: Supporting evidence-based conformity assessments for medical device approvals and market surveillance in accordance with the EU Medical Device Regulation (MDR 2017/745).
• Healthcare Providers and Procurement: Ensuring supplied prosthetic components are tested to validated standards, minimizing the risk of structural failure in clinical use.

By adhering to FprEN ISO 10328, stakeholders can enhance patient safety, product reliability, and facilitate market access for innovative prosthetic devices.

Related Standards

Consider reference to the following connected standards for a comprehensive approach to prosthetic device evaluation:

• ISO 22523:2006 - Requirements and test methods for lower limb prostheses
• ISO 22675:2016 - Additional test procedures for ankle-foot devices and foot units
• EN ISO 13485 - Quality management systems for medical device manufacturers
• EN ISO 14971 - Application of risk management to medical devices

Keywords: FprEN ISO 10328, lower-limb prostheses, prosthetic testing, structural strength, cyclic testing, prosthetics standards, conformity assessment, ISO 22523, CEN, medical device regulation, patient safety, prosthetic device testing.

SLOVENSKI STANDARD
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
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 10328:2025(en)
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.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
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or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
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RECIPIENTS OF THIS DRAFT ARE INVITED
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TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
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PROVIDE SUPPORTING DOCUMENTATION.
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 10328:2025(en)
ii
ISO/DIS 10328:2025(en)
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

iii
ISO/DIS 10328:2025(en)
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

iv
ISO/DIS 10328:2025(en)
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

v
ISO/DIS 10328:2025(en)
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

vi
ISO/DIS 10328:2025(en)
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.
vii
ISO/DIS 10328:2025(en)
— 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.

viii
ISO/DIS 10328:2025(en)
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.

ix
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
...