ISO 8548-2:2020

INTERNATIONAL ISO
STANDARD 8548-2
Second edition
2020-04
Prosthetics and orthotics — Limb
deficiencies —
Part 2:
Method of describing lower limb
amputation stumps
Prothèses et orthèses — Malformations des membres —
Partie 2: Méthode de description des moignons d'amputation des
membres inférieurs
Reference number
ISO 8548-2:2020(E)
©
ISO 2020

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ISO 8548-2:2020(E)

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© ISO 2020
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Published in Switzerland
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ISO 8548-2:2020(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3  Terms and definitions . 1
4 Stump description . 1
4.1 General . 1
4.2 Stump characteristics . 1
4.3 Skin . 2
4.4 Circulation . 2
4.5 Pain. 2
4.6 Phantom sensation and phantom pain . 2
4.7 Joint function . 2
4.7.1 Measurement of abnormal range of joint movement. 2
4.7.2 Assessment of stump muscle strength . 2
4.7.3 Assessment of joint stability . 2
4.7.4 Joint pain . 3
5 Measurement of lower limb amputation stumps . 3
5.1 Reference levels and reference planes . 3
5.1.1 General. 3
5.1.2 Reference levels . 3
5.1.3 Reference planes used for partial foot amputations . 4
5.2 Measurements . 4
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ISO 8548-2:2020(E)

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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
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 second edition cancels and replaces the first edition (ISO 8548-2:1993), which has been technically
revised. The main changes to the previous edition are as follows:
— the stump descriptors (Tables 1 to 7) have been revised;
— the lists of measurements to be taken by all members of the team and the additional measurements
to be taken only by the prosthetist have been revised (Table 8).
A list of all parts in the ISO 8548 series can be found on the ISO website.
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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ISO 8548-2:2020(E)

Introduction
This document provides a standard method for describing and measuring amputation stumps. Such
a method is essential to allow comparisons of the outcomes of amputation surgery and rehabilitation
provided by different teams.
The healthcare professionals who will use the method include surgeons of different disciplines, other
doctors (especially those concerned with rehabilitation), nurses, physical and occupational therapists
and prosthetists.
Such a method is also of value to epidemiologists and government health officials.
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INTERNATIONAL STANDARD ISO 8548-2:2020(E)
Prosthetics and orthotics — Limb deficiencies —
Part 2:
Method of describing lower limb amputation stumps
1 Scope
This document establishes a method of describing and measuring lower limb amputation stumps. It
also lists the measurements required for the provision of a prosthesis.
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 document (including any amendments) applies.
ISO 8549-2, Prosthetics and orthotics — Vocabulary — Part 2: Terms relating to external limb prostheses
and wearers of these prostheses
ISO 8549-4, Prosthetics and orthotics — Vocabulary — Part 4: Terms relating to limb amputation
3  Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8549-2 and ISO 8549-4 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Stump description
4.1 General
Specify the amputation side and describe the stump using the relevant descriptors listed in the
appropriate tables (Tables 1 to 7) and the guidance given in 4.2 to 4.6.
4.2 Stump characteristics
The shape of the stump should be described as either conical, bulbous or cylindrical. In this context, the
meanings of these terms are self-evident.
The soft tissues of the stump should be described by reference to their amount and consistency. The
amount should be described as sufficient, insufficient or excessive and the consistency described as
normal, flabby or indurated. If the heel pad is retained, its position should be recorded as correctly
positioned, displaced or mobile.
It is important to record whether the stump musculature is attached, detached or displaced.
Relevant bony features such as prominences, remnants, length or position should be described. The
presence of any prominent foreign bodies, for example grafts, implants or shrapnel, should be noted.
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ISO 8548-2:2020(E)

Where appropriate, the end-bearing status of the stump should be recorded.
For partial foot amputations, record the level of amputation specified in ISO 8549-4. The complete
description requires the identification of the amputated bones and their levels of amputation.
4.3 Skin
Record whether the skin barrier is intact or not, and whether the skin has normal sensation.
The position/orientation of the incisional scar and whether it is healed or not and mobile or adherent
should be recorded. Additionally, the presence and condition of other scarring or skin grafting should
be noted.
Any history of skin pathology, for example contact dermatitis, skin allergy and/or hyperhidrosis, should
be noted.
4.4 Circulation
The factors which should be described concerning the circulation are colour, temperature and oedema.
The skin should be described as either normal in colour, cyanotic or otherwise discoloured, and as
warm to examination or not.
The presence of excessive oedema should be noted. Excessive oedema is considered as that which would
adversely affect stump healing or prosthetic fitting and use.
4.5 Pain
Significant pain is regarded as that which is greater than expected at the stage of treatment.
The presence of significant pain or tenderness from whatever source (e.g. painful neuroma, pain after
exercise or from prosthetic use) should be recorded using an appropriate pain scale.
4.6 Phantom sensation and phantom pain
Phantom sensation and phantom pain are sensation and pain felt as if in the amputated part of the limb.
Phantom sensation is common after amputation and does not normally require treatment. Phantom
pain varies in intensity and should be recorded using an appropriate pain scale.
4.7 Joint function
4.7.1 Measurement of abnormal range of joint movement
Abnormalities of the range of joint movement in the proximal joint(s) of the amputated limb should be
recorded using the neutral zero method in which zero is the anatomical position.
4.7.2 Assessment of stump muscle strength
Reduced strength of the muscle groups responsible for producing movements at the proximal joint(s) of
the amputated limb should be recorded using the manual muscle testing 0–5 scale.
4.7.3 Assessment of joint stability
Instability of the proximal joint(s) of the amputated limb, which is a consequence of bony or ligamentous
impairments, should be recorded.
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4.7.4 Joint pain
Pain in the proximal joint(s) should be recorded.
5 Measurement of lower limb amputation stumps
5.1 Reference levels and reference planes
5.1.1 General
Identify the reference levels and planes relevant to the particular level of amputation as described in
5.1.2 and 5.1.3.
5.1.2 Reference levels
5.1.2.1 Waist
The level midway between the costal margin and the iliac crest.
5.1.2.2 Iliac crest
The level defined by a line joining the highest point on the crest of each ilium.
5.1.2.3 Proximal
The most proximal level at which a circumferential measurement, perpendicular to the mid-line of the
thigh, can be obtained.
5.1.2.4 Minimum circumferential
In knee and ankle disarticulation stumps only, the level of the minimum circumference.
5.1.2.5 Femoral condylar
In knee disarticulation and transcondylar amputation stumps only, the level of the maximum condylar
circumference.
5.1.2.6  Inflection
In transfemoral and transtibial stumps only, the level on the stump at which the slope of the stump
shape changes as it curves in towards the end.
5.1.2.7 Stump end
The level of the stump end.
5.1.2.8 Medial joint line
The level of the medial tibial plateau, unless there is a fixed deformity of the knee, in which case this
level is the highest at which a circumferential measurement perpendicular to the mid-line of the stump
can be obtained.
5.1.2.9 Mid-patellar tendon
The level mid-way between the origin and insertion of the patellar tendon.
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5.1.2.10 Malleolar
In ankle disarticulation stumps only, the level of the maximum distal circumference.
5.1.2.11 Ground
The level on which the patient is standing barefoot.
5.1.3 Reference planes used for partial foot amputations
5.1.3.1 Heel
The plane at the posterior aspect of the heel parallel with the mid-line of the leg.
5.1.3.2 Anterior tibial
The plane at the anterior aspect of the tibia at the ankle joint line parallel with the mid-line of the leg.
5.1.3.3 Stump end
The plane at the stump end parallel with the mid-line of the leg.
5.1.3.4 Toe
The plane at the tips of the toes of the contralateral leg parallel with the mid-line of the leg.
5.2 Measurements
This document does not specify the method to be used to obtain the measurements. It specifies both
the measurements which should be taken by the team responsible for the rehabilitation of the person
and those to be taken only by the prosthetist responsible for the provision of a prosthesis.
In order that the description of the stump can be related to the person as a whole, the contralateral limb
needs some minimal measurement.
Measure and record the length, circumferential, width and antero-posterior measurements as specified
in Table 8 and illustrated in Figures 1 to 6 for the level of amputation.
The posture of the person in which the measurements are taken should be recorded.
Table 1 — Descriptors for transpelvic amputations
Descriptor Statement to be recorded
Stump characteristics
Pelvic remnant Present/absent
Soft tissues of the stump
Amount Sufficient/insufficient/excessive
Consistency Normal/flabby/indurated
Skin
General Skin barrier intact/skin barrier not intact
Sensation normal/sensation impaired
Incisional scar Healed/unhealed
Mobile/adherent
Additional scarring or grafting Healed/unhealed
Mobile/adherent
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Table 1 (continued)
Descriptor Statement to be recorded
Pathology Inflammatory conditions (
...