CE marking or norm in relation to components for prosthetic arms

CE-marking or norm

The CE-marking establishes that a particular item or product conform to European product law in relation to health, safety, and environmental protection standards [link].

As this text is not public or may be hard to get into the public eye, why not just go ahead and drag it out. I started to be interested by the backgrounds of what our prosthetic limbs and their technical documentation ideally could be already a few years ago [link].  So, a few blog posts here do have a long history, longer than others, and were assembled over quite a period of time.

Devices are promised to function in a certain way, which is the one that is also intended, declared and promoted in instructions, label and in promotional materials

The CE marking generally is required for certain devices or products to be used in a medical context. CE stands for conforming to European law. There, document #31993L0042 (Council Directive 93/42/EEC of 14 June 1993 concerning medical devices, Official Journal L 169 , 12/07/1993 P. 0001 - 0043) (pdf) defines that the relevant purpose, the function to be achieved, the promise to be delivered is contained in Article 1 (2) (a), which reads as follows:

Article 1 (2)

  • "Article 1 (..) 2. For the purposes of this Directive, the following definitions shall apply:
  • (a) 'medical device' means any instrument, apparatus, appliance, material or other article, whether used alone or in combination, including the software necessary for its proper application intended by the manufacturer to be used for human beings for the purpose of: - diagnosis, prevention, monitoring, treatment or alleviation of disease, - diagnosis, monitoring, treatment, alleviation of or compensation for an injury or handicap, - investigation, replacement or modification of the anatomy or of a physiological process, - control of conception, -- and which does not achieve its principal intended action in or on the human body by pharmacological, immunological or metabolic means, but which may be assisted in its function by such means."
  • (...)
  • "(g) 'intended purpose' means the use for which the device is intended according to the data supplied by the manufacturer on the labelling, in the instructions and/or in promotional materials".

Comment to Article 1(2) in context of prosthetic arms

As below elbow amputee, the predominant handicap (as disfigurement is not specified in the CE norm) consists, functionally, in a shorter arm with limited or diverging possibilities to grasp, manipulate or act, definitely without a hand, seeing as if the hand and wrist including a bit of the arm are absent. The actual content of the disability of arm amputation are (1) phantom pain [link], (2) disfigurement, (3) practical handicap with limited divergent or entirely absent grasp, hold, manipulation and from that, (4) bodily asymmetry and possible overuse issues. As prosthetic arms are devices, they need to (5) look good, (6) be reliable, robust and sturdy, (7) be affordable, (8) be functional and useful and (9) cheap and easy to maintain, also (10) not cause direct side effects such as skin rashes or injury, bodily pain or dysbalance. To address the handicap, necessarily, one or several aspects of (1) through (4) as well as (5)-(10) will have to be addressed.

From that implication come expectations.

More specifically, promotional materials and instructions by the manufacturer set the stage on which these promised function improvements are conveyed and in fact legally implemented vice versa the CE-norm law. Any CE-conformant device related promises and the expected purpose are also, and in other words, specifically, not, to perpetuate, aggravate, add burden to, or exacerbate the handicap in any way. Thus, the medical device, prosthesis, or hook, wrist including controls have a clear purpose, that is to treat, alleviate or compensate for impaired grasping. This also means that in no unclear terms, manufacturers must not advertise what their device does not deliver.

Body-powered arms actuate springs or rubbers that are sources of power external to the body, and myoelectric arms are battery driven electrical motor devices.

Annex IX, Classification criteria, I: classification of medical devices such as prosthetic arms as external prostheses

So classification wise, prosthetic devices that fall under body powered or myoelectric systems are Active Medical Devices (Annex IX, Classification criteria, I - Definitions: 1.4: "Any medical device operation of which depends on a source of electrical energy or any source of power other than that directly generated by the human body or gravity and which acts by converting this energy. Medical devices intended to transmit energy, substances or other elements between an active medical device and the patient, without any significant change, are not considered to be active medical devices"), class I devices (Annex IX, Classification criteria, III - Classification "1. Non-invasive devices - 1.1. Rule 1 - All non-invasive devices are in Class I, unless one of the rules set out hereinafter applies".

However, energy is indeed exchanged for body powered or myoelectric arms, so we are looking at "3.1. Rule 9 - All active therapeutic devices intended to administer or exchange energy are in Class IIa unless their characteristics are such that they may administer or exchange energy to or from the human body in a potentially hazardous way, taking account of the nature, the density and site of application of the energy, in which case they are in Class IIb. All active devices intended to control or monitor the performance of active therapeutic devices in Class IIb, or intended directly to influence the performance of such devices are in Class IIb".

Annex I/3: the devices are obligatory to actually deliver the promised function

In Annex I, we read "3. The devices must achieve the performances intended by the manufacturer and be designed, manufactured and packaged in such a way that they are suitable for one or more of the functions referred to in Article 1 (2) (a), as specified by the manufacturer. "

Annex I/1 and /2: the manufacturers have additional duties

We read Articles 1 and 2 of Annex I: "

  • 1. The devices must be designed and manufactured in such a way that, when used under the conditions and for the purposes intended, they will not compromise the clinical condition or the safety of patients, or the safety and health of users or, where applicable, other persons, provided that any risks which may be associated with their use constitute acceptable risks when weighed against the benefits to the patient and are compatible with a high level of protection of health and safety. --
  • 2. The solutions adopted by the manufacturer for the design and construction of the devices must conform to safety principles, taking account of the generally acknowledged state of the art. In selecting the most appropriate solutions, the manufacturer must apply the following principles in the following order: - eliminate or reduce risks as far as possible (inherently safe design and construction), - where appropriate take adequate protection measures including alarms if necessary, in relation to risks that cannot be eliminated, - inform users of the residual risks due to any shortcomings of the protection measures adopted."

In short, manufacturers also have to inform the user of the possible ill side effects, and where appropriate install an alarm or identify risks and tell the user.

Annex II: manufacturing and design requirements

Section II of Annex I says "II. REQUIREMENTS REGARDING DESIGN AND CONSTRUCTION 7. Chemical, physical and biological properties - 7.1. The devices must be designed and manufactured in such a way as to guarantee the characteristics and performances referred to in Section I on the 'General requirements'. Particular attention must be paid to: - the choice of materials used, particularly as regards toxicity and, where appropriate, flammability, - the compatibility between the materials used and biological tissues, cells and body fluids, taking account of the intended purpose of the device. -- 7.2. The devices must be designed, manufactured and packed in such a way as to minimize the risk posed by contaminants and residues to the persons involved in the transport, storage and use of the devices and to the patients, taking account of the intended purpose of the product. Particular attention must be paid to the tissues exposed and to the duration and frequency of exposure. -- 7.3. The devices must be designed and manufactured in such a way that they can be used safely with the materials, substances and gases with which they enter into contact during their normal use or during routine procedures; if the devices are intended to administer medicinal products they must be designed and manufactured in such a way as to be compatible with the medicinal products concerned according to the provisions and restrictions governing these products and that their performance is maintained in accordance with the intended use. -- 7.4. Where a device incorporates, as an integral part, a substance which, if used separately, may be considered to be a medicinal product as defined in Article 1 of Directive 65/65/EEC and which is liable to act upon the body with action ancillary to that of the device, the safety, quality and usefulness of the substance must be verified, taking account of the intended purpose of the device, by analogy with the appropriate methods specified in Directive 75/318/EEC. -- 7.5. The devices must be designed and manufactured in such a way as to reduce to a minimum the risks posed by substances leaking from the device. -- 7.6. Devices must be designed and manufactured in such a way as to reduce, as much as possible, risks posed by the unintentional ingress of substances into the device taking into account the device and the nature of the environment in which it is intended to be used."

Comment to Annex I/3, I/1, I/2 and II

So, to work well relative to the promised function, that is not a bit facultative under the CE norm.

So, devices cannot just achieve any lower performance.

The performance to achieve is the intended performance, and not the actually achieved one - and the verb is "must".

To recap the referenced Article 1(2)(a) and (g):

  • alleviation or compensation of the handicap is the legally stated aim; if a device increases the handicap or causes harm, this is not conformant with the CE label;
  • the device must achieve any performance intended, or mentioned, declared or raised in the data that is contained in the instructions and promotional material; if any data promises a better, higher, more reliable or extensive function, then the device does not conform to the CE label.
  • the device must not compromise the clinical condition or safety, and where applicable other persons, whereas the design must conform to safety principles that are state of the art; if the device does compromise the clinical condition or safety, the device is not CE label conformant;
  • the manufacturer must inform the user of residual risks due to any shortcomings of the protection measures applied; if they do not, there goes the CE conformance;
  • for sockets and liners as well as for prosthetic grippers, 7.1 is most relevant in addition to above statements: basically, conformance with the regulation requires manufacturers to guarantee characteristics and performances, and to check materials compatibility both with each other and with, e.g., the skin of the user

Examples of actual promotional promises and intentions, declared functions

Otto Bock - promise: Quality for Life

Promise, label, documentation Actual experiences
Movohook 2Grip: [pdf]

"1 Verwendungszweck - Die MovoHook 2Grip 10A70=* und 10A80= sind ausschließlich zur exoprothetischen Versorgung der oberen Extremitäten zu verwenden. Sie sind zur Anfertigung einer zugbetätigten Armprothese vorgesehen. Vorteile der Kraftzughooks: Robust gegen Kraft- und Schmutzeinwirkung. Präzises Greifen auch von kleinen Gegenständen. Vielseitige Greiffunktionen. (..) Der Hersteller weist ausdrücklich darauf hin, dass dieses Produkt nur in den vom Hersteller freigegebenen Bauteil-Kombinationen (siehe Bedienungsanleitungen und Kataloge) zu verwenden ist." (English: the MovoHook 2Grip 10A70=* and 10A80=* are solely intended for exoprosthetic fitting of amputations of the upper limb. The hooks are designed for creating a cable-controlled arm prosthesis. Cable-activated hooks feature: A rugged design that withstands the effects of forces and dirt. The ability to grip even small objects with precision. Versatile gripping functions. (...) The manufacturer explicitly states that this product may only be used in combination with components that were authorized by the manufacturer (see instructions for use and catalogs)).

"Der MovoHook 2Grip ist durch neuartige Gleitlager wartungsfrei. Verschleissteile können bei Bedarf durch den Otto Bock Service ausgetauscht werden." (The MovoHook 2Grip does not require maintenance thanks to a new type of slide bearing. If necessary, worn out parts can be be replaced by Otto Bock Service.)

Claim regarding the ability to grip even small objects with precision: an unaltered, unmodified Otto Bock Movohook 2Grip would, after a short while of using it, not close fully any more, likelye due to faulty design [link] that then requires a user fix.

Claim regarding versatile gripping functions:

The gripping function is that of a split hook with a fixed geometry. How that can be a "versatile" function is impossible to understand. However, understandability or sensible content is not an explicit CE-label requirement. They are uncool but legal to provide gibberish as advertising as that also cannot be wrong, technically. So they may write "the hook has a versatile grip" just as much as they may write "the hook is birdish" or maybe "the hook is curalla trallala parallala". No one could prove the contrary.

Claim that the MovoHook 2Grip does not require maintenance thanks to a new type of slide bearing:

With the promise that a Movohook 2Grip is robust to effects of dirt and forces, and, that the wrist can be used with this body powered hook, the manufacturer then gives contradicting advice in the ensuing warnings regarding the wrist. The wrist, which is a required component, to be used with the hook, fails to deliver the hook's promise.

Claim of the hook joint being marked as service free and the hook as robust. In fact the joint is not service free but contains non-parallel metal surfaces where a plastic disc grinds against the metal surfaces. The user has to fix this at least minimally by adding own brass inlays. No one however cares about this discrepancy as no one is interested in checking CE norms or prosthetic arm grippers where users are probably getting billed extra for the product "conforming" to CE norms.

The manufacturer will clearly want to explain just why they designed their product so the reality of their devices is discrepant from their advertising or promotion ("robust", "wartungsfrei"), how they did not avoid that I misunderstood them and in fact they were not one bit offering any classy, robust, useful or otherwise top of the line performing prosthesis.

How can they believe that even getting me as a customer is good business when in fact, I feel that they totally exaggerated their claims, leaving CE-label conformance somewhere out in the open, wondering what they had been about?

Good CE-label conforming products will in all likelihood include a promotion and documentation that avoids people believing that the device can do what really it cannot do, and it does so without generating any misunderstanding.

"Die Otto Bock Rastenlosen Handgelenke 10V9 /10V10 und 10V25 können mit einem Otto Bock Kraftzughook oder mit einer Otto Bock Systemhand eingesetzt werden." (The Otto Bock wrist 10V9 / 10V10 and 10V25 can be used with an Otto Bock Kraftzughook or with an Otto Bock system hand)

Wrist: [pdf]

Wrist restrictions: "Verletzungsgefahr durch Überbeanspruchung. Die hier beschriebenen Otto Bock Prothesenpassteile wurden für Alltagsaktivitäten entwickelt und dürfen nicht für außergewöhnliche Tätigkeiten wie z.B. für Extremsportarten (Freiklettern, Paragleiten, etc.) eingesetzt werden. Sorgfältige Behandlung der Passteile und ihrer Komponenten erhöhen nicht nur deren Lebenserwartung, sondern dienen vor allem der Sicherheit des Patienten. Sollten Passteile extremen Belastungen ausgesetzt worden sein (z.B. durch Sturz), müssen diese umgehend von einem Orthopädie-Techniker auf Schäden überprüft werden. Ansprechpartner ist der zuständige Orthopädie-Techniker, der die Prothese ggf. an den Otto Bock-Service weiterleitet. -- HINWEIS: Korrosionsgefahr. Prothesenpassteile dürfen nicht Umgebungen ausgesetzt werden, die Korrosionen an den Metallteilen auslösen, wie z. B. Süßwasser, Salzwasser und Säuren. Bei Einsatz eines Medizinproduktes unter diesen Umgebungsbedingungen erlöschen alle Ersatzansprüche gegen Otto Bock HealthCare. HINWEIS: Beschädigung durch falsche Umgebungsbedingungen. Prothesenpassteile dürfen nicht intensiven Rauch oder Staub und nicht Vibrationen, Stößen oder großer Hitze ausgesetzt werden. Es dürfen weder feste Teilchen noch Flüssigkeiten eindringen. Nichtbeachtung kann zu Fehlfunktionen und Beschädigungen der Prothese führen." (Risk of injury from overuse. The Otto Bock prosthesis fittings described here have been developed for everyday activities and may not be used for exceptional activities such as for extreme sports (free climbing, paragliding, etc.). Careful treatment of the components and their components not only increase their life expectancy, but also help the patient to be safe. If the components are exposed to extreme loads (eg by fall) they must be checked immediately by an orthopedic technician for damage. The contact person is the responsible orthopedic technician who, if necessary, passes the prosthesis to the Otto Bock service. - NOTE: Risk of corrosion. Parts should not be exposed to environments which cause corrosion on the metal parts, Fresh water, salt water and acids. If a medical device is used under these environmental conditions, all claims against Otto Bock Health Care expire. NOTE: Damage caused by incorrect environmental conditions. Prosthetic parts should not be exposed to intense smoke or dust, or vibrations, bumps or high heat. Neither solid particles nor liquids must penetrate. Failure to do so can lead to malfunctions and damage to the prosthesis.)

The manufacturer

  • advertises a hook as particularly robust
  • requires the user to only use Otto Bock wrist units
  • and then declares that the wrist units are far from robust when confronted with sturdy use requirements

It is a very cunning way to trick a customer in need for robust equipment to "hook them" via the hook product and then make them stop using the hook as robust tool because the wrist does not hold up.

Overall, the CE-label seems a bit curious here because really, the prosthetic hook of Otto Bock in conjunction with that wrist unit would need to be advertised with "seriously reduced robustness due to brand-linked combination with fragile wrist unit" in order to have the actual product conform with what the law really requires.

If they had invested all that time into design and manufacturing rather than silly product combinations, we would not worry about the CE-label at all.

Otto Bock claims that their devices offer or contain "quality for life".

It is my personal experience that this is not an impression their products made on me, ever. I had to run around to get their shit replaced or fixed so much it ain't funny. So, "crap for five seconds, crap for ten minutes, crap for four days" and "crap for a few months" would be a serious honest way to label their produce, given the relatively insane pricing.

if anything, it is a proud and worthy claim, asking for improvement cycles where users and engineers cooperate in improving these devices.

Also that is not an experience that their products or representatives allowed for in my instances.

My Otto Bock cable setups tore up between 4-10 days of use for a period of about two years (link) - then, I started with own patented developments (link).

My Otto Bock Movowrist permanently jammed within 5 seconds of first use.

My Otto Bock hook silver/gold jammed due to thermal material expansion under warm water (link).

My Otto Bock terminal device adapters did not fit Otto Bock wrist well, both with freely turning and jammed adapters due to wide spread bolt diameters (link).

Otto Bock figure 9 harness caused brachial plexus damage that was not permanent but recovered only over several weeks of not using that harness, so it contained a serious injury risk (link). That risk is not contained in their product documentation.

The promise "quality for life" thus will require an  extensive and clear explanation in how that promotional explanation into a expected product longevity really it is conformant to the CE-label laws, as to any user such as me, that is not readily apparent.

 

 

iLimb Ultra Revolution - promises: unsurpassed function, most versatile hand on the global market

iLimb: [pdf]

 

Promise, label, documentation Actual experiences
"The i-limb® product range, combines unsurpassed functionality with style. [pdf] Unsurpassed functionality:

The iLimb will have a seriously flawed precision grip alignment. The precision grip alignment however is perfect in a prosthetic split hook, as an example. A split hook very clearly surpasses the functionality of an iLimb in terms of this aspect. Also, a Becker hand has a fully reliable precision grip and thus clearly surpasses an iLimb with regard to that. Hence, the precision grip as main aspect of any prosthetic terminal device used for ADL and grip is not unsurpassed.

The iLimb seriously lacks grip force. It really is very weak. It is surpassed by many other devices with regard to that, so it is not unsurpassed.

The software really does not start, mostly. What it does is, it crashes very often. So, that type of functionality is easily surpassed by, say, my weather app on my mobile phone. Thus, functionality of the iLimb software is not unsurpassed but surpassed.

As "unsurpassed" is a rather comprehensive claim, showing that the iLimb is substandard and fails even in just one account does away with the iLimb offering unsurpassed function.

Unsurpassed style:

The style of the iLimb clearly s that of broken dreams. In that, it is unsurpassed. So we have to acknowledge that the style of the iLimb is as advertised.

Still, the striking lack of true functionality is in some tension and apparent contradiction to the promotional style of the documentation. It will require a good explanation just how such claims are in keeping with CE-label requirements.

"Individually motorized digits, stall detection and the unique software used to control the i-limb® hands result in the most versatile prosthetic hands currently available to the global market." [pdf]

"The i-limb ultra revolution prosthetic hand is designed for those who want the most advanced and versatile prosthesis available." ([link],2014)

I define versatile as "The word versatility describes having many different skills or qualities. Versatility allows you to adapt to many different situations. (link).

This is clearly does not appear to be the case as such from my view, so the term "versatile" requires narrow restriction to avoid being misunderstood.

"The i-limb® hand is for low to moderate impact activities. It should not be used for heavy lifting or be exposed to excessive forces or vibration. The i-limb® hand cannot absorb any shock as your own body is able to do. If high degrees of force are applied, you may cause damage to your i-limb® hand. If this does happen, then please contact your clinical team." [pdf]

 

This is a great statement showing that the manufacturer tried to at least make the device promotion and documentation somewhat compatible with CE-label legislation.

Obviously, a precise declaration of what this device really can and cannot do would go a whole lot further from my own experience.

"Damaged covers must be replaced or repaired by a qualified Touch Bionics technician or technical partner".  [pdf] A typical piece of evidence demonstrating how little reflected these documentation and promotional materials really are.

  • This means that a user is fine with replacing an intact glove which is harder, than replacing a damaged glove, which can be cut off as it will be discarded anyway.
  • Logically, this means that the user manual, that details how to don and doff gloves / covers, is applicable for intact gloves.
"Choose from a wide selection of automated grips and gestures to help you complete your daily tasks, such as index point for typing, precision pinch mode for gripping small objects or natural hand position for walking or while at rest." ([link],2014) A CE-label compliant product documentation of the iLimb may also have to extensively inform the user about the properties that constitute more serious short comings of the device.

Otherwise you risk that the customer will turn the quest into all the stuff the device cannot do but that then comes as a bad awakening due to promotional and documentation materials not sufficiently informing about ill design, bad engineering, and such, into an Indiana Jones adventure just as I am doing it (e.g., [link]).

The manufacturer thus may have to explain just how poor their device documentation and promotional material was to allow a user such as me to identify their device as at least remotely useful when, in fact, it can almost only serve as a research and development device, but not as reliable prosthetic hand to win all hearts and grip situations ever, and how that discrepancy adds to this device actually conforming to the CE-label. Because from where I am standing, they overadvertised an ill-designed alpha-version of what is sold as insanely overpriced gadget and tore open some serious question about just exactly how this prosthetic hand ever got tested and approved.

Watch my very patient dozens of attempts to start the software on Android to cool your rage (I exaggerate only mildly) [link].

 

Ossur Upper-X silicone liners and pin-locks

My own experience wearing these covers a few years really, with a number of negative aspects:

  • frequent early tearing off of the fabric at the liner rims
  • congestion eczema due to poor fit to the stump
  • profuse sweating and frequent skin rashes

So the question is, whether the documentation leads up to these aspects by helping the novice or experienced user, as well as technician, to better make decisions there. Or, whether the documentation and promotional materials really leave everyone in the dark about real life experiences. Some relevant documents are the user manual [link] and tech sheet for the product [link], with the CE-label at the bottom of the last page.

 

Documentation and promotional material Actual experience
"The Iceross Upper-X liner is a comfortable liner with an excellent suspension method for upper-extremity amputees." (link)

"Liner Sizing - To determine the correct Iceross size: A. Measure the circumference of the residual limb 4cm from the distal end. B. Choose the Iceross size which corresponds to the measurement or which is immediately below the indicated measurement. C. Never choose a liner size which exceeds the measurement or round up"

"Selecting the correct size is very important. If the liner is too tight, this may cause pistoning and / or numbness and blistering. If the liner is too loose, increased perspiration and / or movement of the limb inside the liner may occur. Perspiration and movement can lead to blisters and rashes. If any of the above symptoms or any other indication of improper fit are noted, the user should be instructed to contact his / her physician or prosthetist immediately."

I did get extensive stump rashes as fast as two hours into wearing the liner. The occurrence of rashes is not noted in the documentation.

They are very frequent and always uncomfortable. This is such a real problem for many users, I never understood how these manufacturers will not clearly address this as one of their key problems that the product of a liner will produce after wearing it for as little as 2 hours but mostly after 1-2 days.

I did sweat profusely inside the liner but was always told it was normal.

Ossur specifies a 1-place measurement to estimate the liner fit: 4 cm from the distal end. As reality has it, a fit or non-fit is not adressed adequately with a single diameter but a fit or non-fit must be based on the fact that a stump will have different diameters [link], possibly more different than any given Ossur liner. In other words, I got a chronic congestion eczema from the liner being too tight, without blistering or numbness. After that, it was me that provided the cogent measurements myself [link]. So their text is not correct in that critical details are missing. You need several measurements, as a liner has to be snug all along the stump.

Congestion eczema, with brownish discoloration, had been then examined and treated by a dermatologist as well. Part of the long-term treatment was changing liners to a model that provides an actual fit, unlike the Ossur Iceross, whose fit / non-fit characteristics were not documented to a sufficient degree in their paper works so any prosthetist or user would know what to look for to begin with, or, at first.

As Ossur wants to sell as many liners as possible, an exact fit cannot be anything they possibly target. Instead, they will not answer any customer / user query into liner shapes1)Mail to Ossur on Dec 14, 2009, unanswered: Sehr geehrte Damen und Herren Ihr Iceross Upper X Liner eignet sich fuer meinen Arm (langer Unterarmstumpf) nur noch ~ bedingt, und zwar, weil Sie eine annaehernd tubulaere Form anbieten. Mein Arm ist aber vorne duenner und hinten breiter. Mit dem Upper X Groesse 14, der vorne am Stumpf zu locker ist, habe ich nun vorne am Stumpf deswegen kleine Taschen, in denen der Schweiss sammelt und wo die Haut daher zu Ausschlag, Pilzinfekt und Ekzem neigt. Am Oberrand neben dem Liner ist dieser viel zu eng, dort habe ich vom starken Druck auch schon kleine Blasen gehabt. Nun ist ja mein Arm vorne seit der letzten Anpassung etwas geschrumpft und ich werde den 12-er Upper X bekommen. Er sollte damit vorne am Stumpf gut passen. Aber leider wird dieser hinten / am Rand sehr unangenehm eng sein, dort wo mein Armstumpf breiter ist. Argumente: - Alle langen Unterarmstuempfe sind vorne schmaler und hinten breiter. - Ihre Daher meine Bitte: - koennten Sie die Upper X Liner alternativ leicht konisch anbieten, vorne beim Pin sollte er etwas enger sein als hinten - koennten Sie auch Zwischengroessen 10, 11 und 13 anbieten Das wuerde meine Situation stark verbessern. Ich weiss von aneren Leuten mit genau solchen Armen, die haben auch alle Custom Liner - waere unnoetig, Besten Dank, Wolf Schweitzer .

 

The customer service website of this company claims "We welcome your comments or questions - Please send us your inquiry by using the form below and we will respond as soon as possible." They responded differently than they advertise or claim.

In one instance, where it was really important for me, I did not get an answer at all 2)Mail to Ossur on Dec 14, 2009, unanswered: Sehr geehrte Damen und Herren Ihr Iceross Upper X Liner eignet sich fuer meinen Arm (langer Unterarmstumpf) nur noch ~ bedingt, und zwar, weil Sie eine annaehernd tubulaere Form anbieten. Mein Arm ist aber vorne duenner und hinten breiter. Mit dem Upper X Groesse 14, der vorne am Stumpf zu locker ist, habe ich nun vorne am Stumpf deswegen kleine Taschen, in denen der Schweiss sammelt und wo die Haut daher zu Ausschlag, Pilzinfekt und Ekzem neigt. Am Oberrand neben dem Liner ist dieser viel zu eng, dort habe ich vom starken Druck auch schon kleine Blasen gehabt. Nun ist ja mein Arm vorne seit der letzten Anpassung etwas geschrumpft und ich werde den 12-er Upper X bekommen. Er sollte damit vorne am Stumpf gut passen. Aber leider wird dieser hinten / am Rand sehr unangenehm eng sein, dort wo mein Armstumpf breiter ist. Argumente: - Alle langen Unterarmstuempfe sind vorne schmaler und hinten breiter. - Ihre Daher meine Bitte: - koennten Sie die Upper X Liner alternativ leicht konisch anbieten, vorne beim Pin sollte er etwas enger sein als hinten - koennten Sie auch Zwischengroessen 10, 11 und 13 anbieten Das wuerde meine Situation stark verbessern. Ich weiss von aneren Leuten mit genau solchen Armen, die haben auch alle Custom Liner - waere unnoetig, Besten Dank, Wolf Schweitzer .

In another instance, I had asked about technical solutions for problems I had with Ossur products and instead got a truly arrogant answer first, that despite a more constructive Ausendienst reply, remained not helpful3)  On Dec 27 2011, I wrote: Hallo Ossur Ich habe eine Armprothese mit Ossur Liner / Icelock Pinlock. Fragen. 1) Das Pinlock lottert immer nach einer Weile wieder. Der Deckel innen kommt etwas weg. Ich benutze die Prothese recht stark und nach Umzuegen mit schweren Kisten oder etwas starker Vibration ist meist der Deckel etwas locker. Gibt es ein Werkzeug von Ossur das in dieses Ding passt und man kann es wieder zuschrauben damit, der Deckel ist ja wie eine Vierkantschraube gemacht? Oder empfehlen Sie mir, selbst ein Werkzeug zu basteln (zB. Sperrholz, richtige Form aussaegen)? 2) Die Liner sind Upper X und der graue Stoff geht immer weg. Mein OT hat keinen Leim oder Kleber von Ihnen wie er sagt. Wie soll ich vorgehen? Haben Sie Moeglichkeit dass ich direkt bei Ihnen Kleber bestellen kann, was kostet das? Gibt es im Modellbau oder sonst Klebstoff den Sie empfehlen? oder koennen Sie die chemischen Inhaltsstoffe Ihres Klebstoffes deklarieren damit ich guenstige Kleber von einem anderen Hersteller kaufen kann? Falls nicht, was muss ich machen um an diese Hinweise zu kommen? Besten Dank  Wolf Schweitzer ---- Reply on Dec 28, 2011: Sehr geehrter "WS", vielen Dank für Ihre wertvolle Hilfe. wir haben Ihre email heute morgen erhalten und diese gleich zur weiteren Bearbeitung an unseren Außendienst in der Schweiz zugesendet, ich werde ihm die Information weiterleiten damit er nicht unnötigerweise Ihnen Ihre Lösung erneut vorschlägt. Leider können wir als Hersteller, Ihnen als Anwender keine Fragen beantworten, daher haben wir für eine Hilfestellung den Außendienst für das technische Problem einschalten wollen. Preise sowie Empfehlungen können wir Ihnen aus rechtlichen Gründen leider nicht nennen, sie können diese jedoch in allen Sanitätshäusern erfragen. Ich möchte Ihnen dennoch einen Optimalen Übergang in das neue Jahr 2012 wünschen und verbleibe höflichst. Mit freundlichen Grüßen, Luis Da Silva Oliveira --- Two days later, the Aussendienst did indeed answer my mail, stating "Fragen. 1) Das Pinlock lottert immer nach einer Weile wieder. Der Deckel innen kommt etwas weg. Ich benutze die Prothese recht stark und nach Umzuegen mit schweren Kisten oder etwas starker Vibration ist meist der Deckel etwas locker. Gibt es ein Werkzeug von Ossur das in dieses Ding passt und man kann es wieder zuschrauben damit, der Deckel ist ja wie eine Vierkantschraube gemacht? Oder empfehlen Sie mir, selbst ein Werkzeug zu basteln (zB. Sperrholz, richtige Form aussaegen)? Es gibt für Ihr Icelock System ein Werkzeugsatz mit dem Sie das Icelocksystem immer wieder fest-ziehen können ! Werkzeugsatz : L - 780000 bestellbar nur von Ihren Orthopädie- Techniker (Össur beliefert keine Privatpersonen ) 2) Die Liner sind Upper X und der graue Stoff geht immer weg. Mein OT hat keinen Leim oder Kleber von Ihnen wie er sagt. Wie soll ich vorgehen? Haben Sie Moeglichkeit dass ich direkt bei Ihnen Kleber bestellen kann, was kostet das? Gibt es im Modellbau oder sonst Klebstoff den Sie empfehlen? oder koennen Sie die chemischen Inhaltsstoffe Ihres Klebstoffes deklarieren damit ich guenstige Kleber von einem anderen Hersteller kaufen kann? Falls nicht, was muss ich machen um an diese Hinweise zu kommen? Zu jedem Liner wird normalerweise eine kleine Tube Silikonkleber mitgeliefert ! Nachbestellbar : I – 400310 bestellbar nur von Ihren Orthopädie- Techniker (Össur beliefert keine Privatpersonen ) Silikonliner auf eine dicke Flasche aufrollen. Den Stoffüberzug (der sich gelöst hat) mit silikonkleber einstreichen. Anschließend die silikonbestrichene Stelle mit Frischhaltefolie (für 24 Std.) umwickeln……..dadurch erhält die rep. Stelle eine glatte Oberfäche.". . They never managed to tell the prosthetist about their often-rumored "silicone glue". That never happened.

Ultimately I changed manufacturer for the liner. I now wear Alpha Liners by Ohio Willowwood.

It is funny how that company:

  • can ask high prices for what essentially is an un-customized mass product (silicone liner) when really the milk industry gets cow udder liners for a lot cheaper, being a similar mass product
  • can not answer customer requests directly, and "thanks me" when really I had asked questions, without actually answering the questions well
  • can not provide silicone glue for disintegrating liners (I never got that material they blathered about, asked my prosthetist numerous times)
  • can not provide a documentation that allows use of their liners without continuous rashes and without the risk of an ill fit with congestion eczema

How that is particuarly compliant with the requirements laid down by CE regulations is something I stopped bothering about as neither Ossur liners nor their customer service provided any actual help down along just any line of inquiry.

Ossur Icelock pin-lock device [link] It is in-te-resting that the manufacturer should publish a document called "instructions for use", but in no way addresses the actual user.

This in my experience is in line with other customer contact attempts with Ossur: they just don't care about treating, or dealing with, the end user. Like, at all. Have Ossur sell to end user directly, maybe tools they really need? Wish in one hand, shit in the other and see which one fills up first.

So the most frequent problem that Icelock pin-locks experience during real work and real use is that they fall out. Yes, you read that right. Their threading comes undone. This is a physical consequence of vibration or vibration-like influences, and the only way to remedy this is to regularly fasten the pin-lock.

I did ask Ossur about this, and in the meantime, I got my prosthetist to give me his tool part [link: how to fix losened Ossur pin lock as user], as Ossur themselves find amputees or end-users too problematic to deal with and do not sell to us, despite clear Swiss laws regarding direct imports that state otherwise.

Ohio Willowwood Alpha Liners

Impressive and awe-inspiring just how an American (not European) company gets their user information so much better than the contenders we looked into above, when considered in conjunction with CE-marking. I really talk about Alpha Liners (gel liners) by Ohio Willowwood [link to user information, link to prosthetist guide].

The fact that they have a superior liner product, one that is really better than Ossur Upper X liners, coincides with a far better and as far as I see it, with that, far more CE-compliant product documentation because, from my user perspective, it matches reality a lot better.

Problem Probable Cause Solution Comment
Locking Liner is “pistoning” up and down in your socket. Your limb may have shrunk. Contact your prosthetist Limbs do shrink, great advice! I had that, too. Needed new socket.
Top edge of liner is rolling down your leg. Liner is possibly too short or too tight. Contact your prosthetist. Leg? Arm? At any rate, this is a relevant information.
Heavy sweating (if you have just recently started wearing the liner). Your body has not yet adjusted to the liner. If you are still sweating after several weeks of liner use- contact your prosthetist. Also- some amputees have found that it helps to apply moderate amounts of unscented alum-based antiperspirant to the residual limb before putting on the liner. Always follow your prosthetist’s instructions and the directions on the product label. Note: non-alum-based products may damage the liner. Probably the first extremely relevant product information about very typical use effects.
Heavy sweating (if you had been wearing the liner for a long time without sweating- and suddenly started sweating again). Air is getting between the liner and the residual limb- possibly because your limb has shrunk. Contact your prosthetist. This is certainly one aspect of heavy sweating - the liner may be too large. If I compare with the Ossur wearing experience I will say that the material makes a difference, too: one just appeared to sweat so much more with the Ossur liners. So, the product information somehow will also have to inform about material choice aspects. One way or another, contacting the prosthetist is the right first step. This is an extremely frequent problem that appears to missing from user information of the other contenders in the race for the best CE-compliant documentation.
Skin irritation all over your residual limb. Not cleaning or disinfecting your liner correctly. Make sure that you are following the proper cleaning- rinsing- and disinfection procedures outlined in this pamphlet. Jackpot!

This nails it with the by far most relevant user information concerning a both frequent and irritating, uncomfortable problem.

Rashes must be addressed.

Generally, rash is not rash. It is relevant to identify a friction rash caused by micro-rubs of a liner that sticks to the skin surface too much, as opposed to a rash on an irritated dry skin, or an infection, or allergic reaction maybe. Friction rashes will be by far the most frequent sort of rash, causing solutions to also address mechanics, friction, not cleanliness.

A relevant additional answer I found most relevant was that cleaning and overcleaning makes things worse, whereas wearing a tube gauze underneath the gel liner practically does away with the friction rash. It is a curious thing that this most prevalent, typical and "normal" use-inflicted rash is not addressed as that on any liner information sheet. Thus, also here seems to be room for improvement.

 

Skin irritation all over your residual limb. Use of a harsh or irritation lotion- cream- powder- or soap. Have you recently started using a different cleaning product? (For some amputees- anti-bacterial soap has caused skin irritations.) Have you recently started using any products that contain hydrocarbon oils or animal fats/oils? If so- discontinue using the product. See above.
Skin irritation all over your residual limb. Washing the limb too frequently. Washing the limb more than once per day can result in increased levels of skin irritation. See above.
Skin irritation all over your residual limb. Fungal and/or bacterial infection of the limb and liner. Contact your prosthetist. You may also need to contact a dermatologist. See above.
Skin irritation all over your residual limb. The liner or the socket is loose- possibly because your limb has shrunk. Contact your prosthetist. See above.
Skin irritation along the top edge of your liner. The liner is being pulled onto the limb instead of being rolled onto the limb- or the liner is too tight. Refer to the instructions in this pamphlet for putting on your liner. If the problem continues- contact your prosthetist. Good and relevant information!
Open wounds and non-intact skin. Contact your prosthetist immediately. Always follow your prosthetist’s directions- and never use a liner in direct contact with open sores or non-intact skin. If the liner must be worn over open sores or non-intact skin- wear a bandage or other appropriate covering over the wound to prevent direct contact between the wound and the liner. Very helpful information.

Wounds or non-intact skin are not generally a problem from my experience but must be addressed on a case-by-case basis, on a day-by-day basis, and taken seriously.

-
- -
- -
- -

Summary

CE-label conformance is an insidious thing.

It appears to require a type of honesty of the manufacturer that makes it seem as if the customer has a right to a very down-to-earth product declaration that at least, from practical view of potential or actual user, matches the product and avoids any purchases with later disappointment.

CE-label conformant products necessarily include a promotion and documentation that avoids people believing that the device can do what really it cannot do, and it does so without generating any misunderstanding.

Some existing products have some interesting or arguable aspects there, from view of a user that applies these devices for real work.

User suggestions

The world needs more user suggestions.

 

Suggestion 1: CE-conformant device information or product declaration for the iLimb

A suggestion for the iLimb by Touch Bionics from my view, would be this:

"The iLimb is a multi-articulated prosthetic hand that is myoelectrically controlled. It thus succumbs to skin-related, sweat-related and temperature-related function drop-outs that can be erratic and frequent. The limb-positioning-effect will cause any hand open or close activity to get triggered without voluntary impulse of the user, during arm or body movement, as inherent problem of myoelectric control. The hand itself is suitably light, which means that the motors are very weak. We can therefore only suggest that you wear very thin glove covers with the hand as thicker gloves will stop the motors from functioning well. We would like you to not change the covers yourself but as of now, we have no idea what gloves do or do not work and we definitely have no idea about how to really test, leave alone build better, glove covers for that device. The iLimb is unable to reliably reproduce a variety of grips, including repetitive precision or oblique lateral grips, also because the thumb lacks sufficient coordination. Therefore, you have to figure out yourself how much reliability and how much surprise the device will bring you. The software to change grips runs on iOS and Android but as it was not programmed too well, frequent crashes are the norm. For that product we ask you to pay an enormous sum of money and in return, you get a no-reply type "customer service"".

Suggestion 2: CE-conformant device information or product declaration for body-powered prosthetic arm parts by Otto Bock

Ah, too funny.

Nope, I think we will leave that one out for the moment. I mean, who cares.

"Otto Bock builds parts for body-powered arms that may carry the chance for considerable health surprises you as a user may find out about eventually. Wearing the figure 9-harness may cause brachial plexus injury with double crush or combined carpal tunnel syndrome that may take extra neurologist, radiologist and other appointments for you to find out about. Wearing our cable sheaths and clamps may cause sudden steel cable rips, as early as after 4-10 days of ongoing use, that can cause skin punctures and abrasions that will then entertain you and keep you busy for another 1-2 weeks until you can get an appointment for repair. Wearing our Movowrist wrist product may cause irreversible block of the device after just one press of a button, or, five seconds into the experience, which ever comes first. Wearing a Movohook 2Grip, advertised as service-free and robust, will cause you to experience inability to grasp fine objects after a few months as we devised material tolerances so that would occur; also, the joint contains just two slightly oblique metal surfaces and a plastic disc, grinding in conjunction with any dirt that got in there, making the occurrence of hook joint wiggle a pleasantly surprising event that you, as user, may solve by adding brass inlays yourself, thereby obviously forgoing our "warranty' clauses".

Suggestion 3: liners may be dangerous products

Liners cause friction rashes on a continous basis. It is what they do, generally. The danger is in causing so many friction rashes, to so many users, that support groups are inundated with reports of friction rashes all the time. That means that a prior clear informative product information to the user quite simply has not happened. And that is a cause for concern if one reads the legal information above.

This is remedied effectively only by following pro-user advice such as by me [link], which is bad in itself, because in fact, product information that complies with CE requirements should sufficiently cover negative effects of using a product that causes skin problems as frequently as liners do. Any new user should know these things before they start using these liners. Regardless of the brand.

With that, the Ohio Willowwood Alpha liner information by far exceeds the Ossur information that I find not so informative really. Maybe we need a meta-level instance that informs about these products from afar.

Suggestion 4: potential future products

Even if you are still doing R&D, you really want to start thinking about your CE-conformant product declarations first. Once you hit the road with any therapies or products, this will be a main aspect that leads the way to getting the product approved for market conformance. But then, if other candidates made it to the market, so can you.

Definition of satire

Satire is a way of making fun of people by using silly or exaggerated language [link].

To provide exaggerated language in promotional material and documentation, assuming sub-standard crappy produce, does have a clear satirical element. So any manufacturer that takes it too far with their things risks that I laugh about it as if it was satire: because, dear manufacturers, it is satire.

Even if you do not believe that to be from your view: if you sell me, say, shitty bolts, that are not worth 3 bucks, but at a price of 80 buck a piece, you clearly make me mad, which must have been your intention, but just as well, you do tickle my satirical streak quite a bit. As I am not a CE-label conformant individual, as user and as amputee, you are dealing with a generally undocumented customer or consumer, where all hell breaks lose once you enter the uncharted territories of over-advertised prosthetic arm parts that fall apart all the time, and none of which appear to have ever seen proper testing and actually accessible documentation of actual technical limits.

Even just reading CE-label legislation and comparing it to prosthetic arm part documentation and promotion materials is funny from a general satirical view. Isn't it!

 

Footnotes   [ + ]

1, 2. Mail to Ossur on Dec 14, 2009, unanswered: Sehr geehrte Damen und Herren Ihr Iceross Upper X Liner eignet sich fuer meinen Arm (langer Unterarmstumpf) nur noch ~ bedingt, und zwar, weil Sie eine annaehernd tubulaere Form anbieten. Mein Arm ist aber vorne duenner und hinten breiter. Mit dem Upper X Groesse 14, der vorne am Stumpf zu locker ist, habe ich nun vorne am Stumpf deswegen kleine Taschen, in denen der Schweiss sammelt und wo die Haut daher zu Ausschlag, Pilzinfekt und Ekzem neigt. Am Oberrand neben dem Liner ist dieser viel zu eng, dort habe ich vom starken Druck auch schon kleine Blasen gehabt. Nun ist ja mein Arm vorne seit der letzten Anpassung etwas geschrumpft und ich werde den 12-er Upper X bekommen. Er sollte damit vorne am Stumpf gut passen. Aber leider wird dieser hinten / am Rand sehr unangenehm eng sein, dort wo mein Armstumpf breiter ist. Argumente: - Alle langen Unterarmstuempfe sind vorne schmaler und hinten breiter. - Ihre Daher meine Bitte: - koennten Sie die Upper X Liner alternativ leicht konisch anbieten, vorne beim Pin sollte er etwas enger sein als hinten - koennten Sie auch Zwischengroessen 10, 11 und 13 anbieten Das wuerde meine Situation stark verbessern. Ich weiss von aneren Leuten mit genau solchen Armen, die haben auch alle Custom Liner - waere unnoetig, Besten Dank, Wolf Schweitzer
3.   On Dec 27 2011, I wrote: Hallo Ossur Ich habe eine Armprothese mit Ossur Liner / Icelock Pinlock. Fragen. 1) Das Pinlock lottert immer nach einer Weile wieder. Der Deckel innen kommt etwas weg. Ich benutze die Prothese recht stark und nach Umzuegen mit schweren Kisten oder etwas starker Vibration ist meist der Deckel etwas locker. Gibt es ein Werkzeug von Ossur das in dieses Ding passt und man kann es wieder zuschrauben damit, der Deckel ist ja wie eine Vierkantschraube gemacht? Oder empfehlen Sie mir, selbst ein Werkzeug zu basteln (zB. Sperrholz, richtige Form aussaegen)? 2) Die Liner sind Upper X und der graue Stoff geht immer weg. Mein OT hat keinen Leim oder Kleber von Ihnen wie er sagt. Wie soll ich vorgehen? Haben Sie Moeglichkeit dass ich direkt bei Ihnen Kleber bestellen kann, was kostet das? Gibt es im Modellbau oder sonst Klebstoff den Sie empfehlen? oder koennen Sie die chemischen Inhaltsstoffe Ihres Klebstoffes deklarieren damit ich guenstige Kleber von einem anderen Hersteller kaufen kann? Falls nicht, was muss ich machen um an diese Hinweise zu kommen? Besten Dank  Wolf Schweitzer ---- Reply on Dec 28, 2011: Sehr geehrter "WS", vielen Dank für Ihre wertvolle Hilfe. wir haben Ihre email heute morgen erhalten und diese gleich zur weiteren Bearbeitung an unseren Außendienst in der Schweiz zugesendet, ich werde ihm die Information weiterleiten damit er nicht unnötigerweise Ihnen Ihre Lösung erneut vorschlägt. Leider können wir als Hersteller, Ihnen als Anwender keine Fragen beantworten, daher haben wir für eine Hilfestellung den Außendienst für das technische Problem einschalten wollen. Preise sowie Empfehlungen können wir Ihnen aus rechtlichen Gründen leider nicht nennen, sie können diese jedoch in allen Sanitätshäusern erfragen. Ich möchte Ihnen dennoch einen Optimalen Übergang in das neue Jahr 2012 wünschen und verbleibe höflichst. Mit freundlichen Grüßen, Luis Da Silva Oliveira --- Two days later, the Aussendienst did indeed answer my mail, stating "Fragen. 1) Das Pinlock lottert immer nach einer Weile wieder. Der Deckel innen kommt etwas weg. Ich benutze die Prothese recht stark und nach Umzuegen mit schweren Kisten oder etwas starker Vibration ist meist der Deckel etwas locker. Gibt es ein Werkzeug von Ossur das in dieses Ding passt und man kann es wieder zuschrauben damit, der Deckel ist ja wie eine Vierkantschraube gemacht? Oder empfehlen Sie mir, selbst ein Werkzeug zu basteln (zB. Sperrholz, richtige Form aussaegen)? Es gibt für Ihr Icelock System ein Werkzeugsatz mit dem Sie das Icelocksystem immer wieder fest-ziehen können ! Werkzeugsatz : L - 780000 bestellbar nur von Ihren Orthopädie- Techniker (Össur beliefert keine Privatpersonen ) 2) Die Liner sind Upper X und der graue Stoff geht immer weg. Mein OT hat keinen Leim oder Kleber von Ihnen wie er sagt. Wie soll ich vorgehen? Haben Sie Moeglichkeit dass ich direkt bei Ihnen Kleber bestellen kann, was kostet das? Gibt es im Modellbau oder sonst Klebstoff den Sie empfehlen? oder koennen Sie die chemischen Inhaltsstoffe Ihres Klebstoffes deklarieren damit ich guenstige Kleber von einem anderen Hersteller kaufen kann? Falls nicht, was muss ich machen um an diese Hinweise zu kommen? Zu jedem Liner wird normalerweise eine kleine Tube Silikonkleber mitgeliefert ! Nachbestellbar : I – 400310 bestellbar nur von Ihren Orthopädie- Techniker (Össur beliefert keine Privatpersonen ) Silikonliner auf eine dicke Flasche aufrollen. Den Stoffüberzug (der sich gelöst hat) mit silikonkleber einstreichen. Anschließend die silikonbestrichene Stelle mit Frischhaltefolie (für 24 Std.) umwickeln……..dadurch erhält die rep. Stelle eine glatte Oberfäche.".

Cite this article:
Wolf Schweitzer: Technical Below Elbow Amputee Issues - CE marking or norm in relation to components for prosthetic arms; published December 25, 2018, 15:20; URL: https://www.swisswuff.ch/tech/?p=7749.

BibTeX: @MISC{schweitzer_wolf_1575482689, author = {Wolf Schweitzer}, title = {{Technical Below Elbow Amputee Issues - CE marking or norm in relation to components for prosthetic arms}}, month = {December},year = {2018}, url = {https://www.swisswuff.ch/tech/?p=7749}}