ISO 8551:2020

INTERNATIONAL ISO
STANDARD 8551
Second edition
2020-03
Prosthetics and orthotics —
Functional deficiencies — Description
of the person to be treated with
an orthosis, clinical objectives
of treatment, and functional
requirements of the orthosis
Prothèses et orthèses — Malformations des membres — Description
de la condition de l'utilisateur d'orthèse, objectifs cliniques, et
exigences fonctionnelles et biomécaniques de l'orthèse
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Description of the person to be treated with an orthosis . 2
4.1 General . 2
4.2 Personal factors . 2
4.3 Health conditions to be treated with an orthosis. 2
4.3.1 Disorders or diseases . . 2
4.3.2 Impairments of body structures and functions . 2
4.4 Other health conditions . 2
4.5 Motivation and perceived needs . 3
4.6 Activity limitations . 3
4.6.1 General. 3
4.6.2 Changing and maintaining body position . 3
4.6.3 Walking . 4
4.6.4 Hand and arm use . 4
4.7 Use of assistive devices . 4
5 Clinical objectives of treatment . 4
6 Functional requirements of the orthosis . 5
Bibliography . 7
Foreword
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described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
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iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 168, Prosthetics and orthotics.
This second edition cancels and replaces the first edition (ISO 8551:2003), which has been technically
revised. The main changes compared to the previous edition are as follows:
— the terminology used in this document has been revised to make it fully consistent with the
terminology used in Reference [5].
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.
iv © ISO 2020 – All rights reserved

Introduction
The quality of life of a person will depend on the health conditions which affect them, the consequential
impairments to the body functions and structures, and the resulting activity limitations
The aim of orthotic treatment is to manage the impairments, reduce the activity limitations and thus
improve participation in all aspects of daily life.
This document provides clinicians with a method of recording the relevant information regarding the
condition of their patients, the clinical objectives of treatment and the functional requirements of the
orthoses provided to achieve these objectives.
A standard method is essential for comparing the clinical practices and the outcomes of treatment
provided in different centres. Such a method is also of value to epidemiologists and government health
officials.
INTERNATIONAL STANDARD ISO 8551:2020(E)
Prosthetics and orthotics — Functional deficiencies
— Description of the person to be treated with an
orthosis, clinical objectives of treatment, and functional
requirements of the orthosis
1 Scope
This document establishes a method of describing the person to be treated with an orthosis, the clinical
objectives of treatment and the functional requirements of the orthosis.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced do
...