Re: Modular adapters rated to the weights grater than 100kg/220lbs??

Re: Modular adapters rated to the weights grater than 100kg/220lbs??

Brian Coop

2/13/2003

On Thu, 16 Jan 2003 18:49:23 +0200, =?iso-8859-9?Q?Ozan_Din=E7el?= <ozan@IB-
ER.COM> wrote:

>Dear List members,
>
>I see that some of the companies have been marketing and presently some of
the companies start to market CE MARKED modular adapters which is rated to
the weights greater than 100kg/220 lbs. I would like share the issue with
you which is confusing my mind. The last international standard-ISO 10328
(the testing of lower limb prostheses) describing the tests up to
100kg/220lbs. However I also know that CE marking of the items requires ISO
10328 test reports of the items. How this companies affix CE mark to the
items which are rated to the weights greater than 100kg/220lbs without the
availability of the formal international test standard?
>
>Thanks
>Ozan
>

As one of the O&P manufacturers that market (and CE mark) components
designed for patients over 100kg (as well as for patients under 60kg),
Fillauer, Inc., feels that a brief discussion of how the CE mark is
assigned and how our products are tested may help to answer this question.
In Article 5 of the EU Medical Device Directive it is written that a
product may be presumed to be in compliance with the essential requirements
if it conforms to harmonized standards (such as ISO 10328, EN 1041, and EN
1441) if such standards exist. It does not explicitly state that a product
can not be CE marked if a harmonized standard does not exist, only that the
particular standards which do exist are applied and which directives have
been fulfilled.

ISO 10328 is an international standard defining the structural testing of
lower-limb prostheses, and in its current state only directly covers
devices designed for three adult weight limits – A60 (60kg, 132lbs), A80
(80kg, 176lbs), and A100 (100kg, 220lbs). As of its publication (in 1996)
only the A100 load level had been validated in field trials. Both the A80
and A60 load levels had been determined statistically from A100. ISO 10328
also states that there were no published standards regarding performance
for pediatric prostheses, but that these standards were under development
along with expanded load levels for adults.

In the meantime, how exactly does a manufacturer design and CE mark
prosthetic devices that do not fit the narrow range explicitly discussed in
ISO 10328? How do we address the need for devices for patients that do not
fit the norm? This is where we, as a manufacturer, need to look at setting
internal requirements based on existing harmonized standards to ensure the
safety of a device beyond the scope of the available harmonized standards.
In the case of lower-limb prostheses, compliance with ISO 10328 is only one
of the many pieces of information available to determine the safety of a
device, and as it is currently written, ISO 10328 is only missing defined
load levels for higher and lower weight patients.

In fact, ISO 10328 addresses its own limitations stating, “The test
procedures may not be applicable to prostheses of mechanical
characteristics different from those used in the consensus.” and, “The
evaluation of lower-limb prostheses and their components requires
controlled field trials in addition to the laboratory tests specified in
the different parts of ISO 10328.” This leaves it open for the manufacturer
to define additional test loads as well as additional test procedures to
use along with our field trials to ensure the structural integrity of
components that are outside the scope of the standard.

Brian Coop
Design Engineering Manager
Fillauer, Inc.