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[WWW]Open Prosthetics is an initiative of the [WWW]Shared Design Alliance.

The Open Prosthetics Project is producing useful innovations in the field of prosthetics and freely sharing the designs. This project is an open source collaboration between users, designers and funders with the goal of making our creations available for anyone to use and build upon. Our hope is to use this and our complementary sites to create a core group of lead users and to speed up and amplify the impact of their innovations in the industry.

This wiki is one of a number of tools available to the Open Prosthetics community to help educate amputees, prosthetic providers and manufacturers, the general public and anyone else that is interested in the field about the history, culture and technology of amputation and prosthetics. In an effort to provide the best that all of these tools offer, we have chosen to provide access to them all, and users are encouraged to use them all, create links from one to another, and to suggest stubs that should be developed. Other sites include
our [WWW]social net, [WWW]The Open Prosthetics Group on Instructables, and [WWW]The Open Prosthetics Google Group.

  1. About
  2. Amputation
  3. Prosthetics
  4. Current Projects
    1. Amputee Preference Census
    2. Open Arms
    3. Open Myoelectric Platforms
    4. Open Standards
    5. RFID Object Identification for Control Information
    6. The OPP "T-Hook," an Updated Trautman-Style Hook
    7. Vector Prehensor
    8. Updating the APRL Hook
    9. New Split Hook
    10. Improved Body Powered Harness
    11. LEGO Hand
    12. Pimp My Arm
    13. Upper Extremity Prosthetic Patent Database
    14. Prosthetic User Repair Kit
    15. Appropriate Technology Prosthetic Solutions
    16. Open Source CAD Program
    17. Cuban Prosthetic Cultural Exchange
    18. Tools for Collaboration on Open Design
    19. Mod Squad
    20. Swimming Prosthesis
    21. D.I.Y. Below Knee Leg Prosthesis
    22. Lego Team Makes Prosthetic Swimming Arm
  5. Useful Links and Tools
    1. Information for People Flying with Prosthetic Limbs and Other Assistive Technology
    2. A Company or Product Here
  6. Discussion
    1. Suggested Projects
    2. Volunteers
    3. Feedback on Collaboration Tools
  7. FAQ


There are just over two million amputees or people with limb absence in the United States. Of these, less than five per cent or fewer than 100,000 are missing an upper extremity. This distribution is somewhat different among veterans of the Iraq and Afghanistan conflicts, from which, as of 2007, there were 862 amputees, of whom 186 are missing arms (as of February 2009). This includes six bilateral upper extremity amputees (that number may be larger by a couple as of 2009). Obviously, there is some overlap, and these numbers refer to individuals, not to limbs. The dramatic difference in the numbers of upper and lower extremity amputees, along with the challenge of replacing a hand or arm as opposed to a foot or leg, conspire to make the prosthetic options for arms less appealing.


The art and science of attempting to replace a limb with a substitute has likely been around as long as limb loss or absence. The history of prosthetics has been somewhat documented, but we would like to start a group effort here. Broadly, prostheses can be divided into Upper Extremity (arms) and Lower Extremity (legs). Additional related areas include [WWW]Anaplastology and Orthotics.

Upper and lower extremity prosthetic components are regulated by the FDA as Class I medical devices. Please contribute to this discussion on the issue.

Prosthetic components are distributed to patients as durable medical equipment, reimbursed by insurance companies and the federal government according to "L-codes." Please see this discussion of all of the business and insurance issues surrounding the provision of prosthetic services and devices. We are frequently contacted by people who are seeking prosthetic limbs for themselves, friends, or family members because they have reached their lifetime insurance cap, or are uninsured. Please consider adding a story about your specific experience and advice for obtaining a limb here.

Within these pages, we would like to give an overview of what types of prosthetic devices are available, give as much information as possible about them, including user reviews of pros and cons, including cost, and describe them with pictures where possible. We are also interested in documenting the challenges to getting good prosthetic care, including the variation in insurance coverage, and the small market in upper extremity prosthetics.

It's worth mentioning here what is NOT available. Fueled by science fiction and the fictionalization of science, prosthetic arms have been imagined as being capable of all kinds of things that they are not. Yet. We've created a round up of arms that would be great to have, if they existed. There are fantasy legs as well.

The representation of amputees and prosthetics in the media, in fiction and fantasy, is interesting and I think says a lot about how we think about amputation as a society. Take a look at this list of Representations of Amputation and Prosthetics in Popular Culture.

Current Projects

Amputee Preference Census

We hear a lot about what amputees want and don't want. We're pretty tired of arguing with anecdotes. Come help us figure out the right questions to ask, and let's ask everyone we can.

Open Arms

This is a project to build a full functional Prosthetic Arm. It uses only open platforms and the designs can be printed in any 3D printer.
This is the VIDEO: [WWW]
and here the Tutorial to build one:!topic/inmoov/vI1sG6WvnQc
Questions can be sent to

Open Myoelectric Platforms

Seeking to expand the user base for myoelectric control, we're hoping to develop myo signal processors that can be used as parts of toys or other user-customizable devices. This is described in more detail here. You can discuss the project in the forum on our Google Group [WWW]site.

Open Standards

While related to the Open Myo Project described above (which will comply with these standards when they are developed), there is a great need within the prosthetic industry (particularly upper extremity) for standards of interoperability. These could extend from mechanical connections, like the Otto-Bock quick disconnect wrist, a de facto standard, to electrical bus standards for communication like the CAN-based OBD-II standard used in automobiles. This topic will be a subject of discussion at a breakout session at the [WWW]MEC 2008 Conference in August, and we have created a project page to serve as a source of information and a place to begin and continue a dialog about the development of these standards.

RFID Object Identification for Control Information

It has been suggested in many places that RFID object information could be useful for augmenting an advanced hand's ability to manipulate and object in context. This could be useful for many types of assistive technology and rehabilitation engineering, as well as home service and hobby robotics. We've started a discussion of the issues associated with aggregating the information that might be helpful to know, and of the mechanics of creating, maintaining and distributing such a database.

The OPP "T-Hook," an Updated Trautman-Style Hook

OPP is seeking to update and return to production an improved hook with many features of the much-loved Trautman Hook. See the project page for more details.

Vector Prehensor

The Vector is an experimental mechanism implemented in a couple of different forms that never made it to production because of patent issues. The inventors have shared the design with the project, and we're looking for folks interested in helping move the open design project toward production. The project is described in more detail, and the documents shared by the inventors are available here.

Updating the APRL Hook

The Army Prosthetic Research Lab (APRL) hook was developed following WWII by the US Army, and has interesting features that distinguish it from other hooks. It is voluntary closing (VC), and has a setting that enables it to lock on the object it closes on. Additionally, it has settings that allow it to open to two different opening distances. While the hook is still produced by Hosmer-Dorrance, some users complain about the durability of the hook and are seeking to update it and increase its durability. Find out more on the project page.

New Split Hook

We've been thinking for a while about updating the split hook, [WWW]versions of which have been around since before WWI. We have a volunteer effort to model an existing hook, and hope to create a design appropriate for plastic injection molding. Check out the project page.

Improved Body Powered Harness

Several problems with the standard figure 8 or 9 body powered harness need fixing. Axillary pressure (in the armpit), slippage and movement, and issues with cleanliness come to mind, among others. An improvement is proposed integrating the harness into a shirt. Check out the project page. Our [WWW]google group page was vandalized but its still up.


Related to the Open Myo project described above, the Project has been pursuing the design of a LEGO hand that could potentially be controlled with myoelectric signals. Volunteer John Bergmann has been working on designs described in the [WWW]group page, which reproduces updates and downloads from our original site. Our ultimate goal is to have the kit available through the user-designed kits section at the [WWW]LEGO Factory site, or even one of the commercial kits. We'd love to have someone helping John figure out how to power the hand. Here's a new project page to help everyone get started.

Pimp My Arm

MTV hasn't threatened to sue us yet, but if they did then we'd get a chance to ask them to be on the show. Any resemblance should be clearly identifiable as parody. And believe it or not, we're not aware of anyone confusing [WWW]Jon with [WWW]Xzibit. Check out the [WWW]explanation of the idea, or go straight to the place where you can post about [WWW]arms, [WWW]legs, or [WWW]whatever you need.

Upper Extremity Prosthetic Patent Database

It's been our belief that for many of the reasons that are discussed above, even receiving a patent on an upper extremity device was no guarantee that the device would ever make it to market, or that it would continue to be available. In fact, it was a 1954 German patent (reference needed), that sunk hopes for the Vector Prehensor to be commercialized. We think that there may be some gems in the patent literature, so we'd like to generate a list of upper extremity patents and the commercial devices (if any) that they led to.

Prosthetic User Repair Kit

We're putting suggestions together here.

Appropriate Technology Prosthetic Solutions

Different economic, social and physical environments demand different solutions to prosthetic problems. These range from differing reimbursement constraints in Europe and the US, to a total lack of infrastructure and funding in parts of the developing world. Social pressures on appearance and function may differ, as may training and materials available in a specific area. Open Prosthetics has begun a partnership with [WWW]Fundacion Amistad, a non-profit, to create a cultural exchange of information about prosthetic technology with the prosthetists and patients of Cuba, beginning with an initial trip in the summer of 2008 the project page to find out more.

Open Source CAD Program

This is something we've hoped would happen for a long time. Perhaps you have, too. Please feel free to comment and document.

There is a very early stage open source CAD program called <groan>[WWW]AcoCADo<\groan> being developed by Adam Kumpf at MIT. It will be interesting to see if this project can gain the momentum necessary to generate the 100 or so lead user developers that it would likely take in order to really get things rolling. We're going to help in any way we can, because this issue is fundamental to the democratization of design.

Cuban Prosthetic Cultural Exchange

Open Prosthetics is beginning a prosthetic cultural exchange with the Cuba Rada Institute, sponsored by Fundacion Amistad. We hope to complete the initial visit by the end of June, and expand the program based on what we learn. Follow our efforts here.

Tools for Collaboration on Open Design

As you may have noticed, we use a collection of free and open tools to allow collaboration on the sharing of physical design ideas. We think there ought to be something better, and we'd like your help in discussing how we might do that.

Mod Squad

I am a student at SVA's MFAD program and I am working to form a group for people who would like to collaborate to modifying donated new and used toys (in addition to other found existing materials needed for reinforcement and functional aspects) into prosthetic arms for kids in developing nations who can't afford a prosthesis.

I don't expect these to be the most advanced high functioning arms but they are better than nothing. We can help a child go from being the kid without an arm to the kid with this awesome arm made from toys! Plus we are finding a way to use existing materials that would otherwise end up in a landfill.

I have created a group on instructables,
It has started some really great conversations about the possibilities of this and realistic materials we could use.

A major issue that I am interested in exploring is cost effective ways to attach the prosthetic to the child's body. Also I am just looking for people who want to experiment with existing materials and see what we can come up with.

So if you want to help make a difference join the Mod Squad!

Swimming Prosthesis

I'm a graduate student at the School of Visual Arts Masters of Fine Art in Design program. I'm working on a project for a Product Design course to redesign a prosthetic arm. I'm interested in creating a better swimming prosthesis.

I'm curious to find out the following:

1. What does the current swimming prosthesis lack?
2. How does the swimming prosthesis affect your balance in swimming?
3. Have you changed the way you swim prior to using the prosthesis vs. with the prosthesis?

If you have any suggestions, comments or would like to collaborate, please contact me.

Thank You,
Irina Lee

D.I.Y. Below Knee Leg Prosthesis

I'm an industrial designer and graduated in 1992 on the design of a D.I.Y leg prosthesis (below knee) for war casualties in Cambodia.
The challenge was to come with a design that a patient could make himself without money, knowledge or training.
My project can be seen/read/downloaded here: [WWW]
I've had lots of support and positive feedback. Yet, the design is never tested in a professional way (many patients for a long time).
I would love to make it become real, but want to be sure it works.

The years I worked in developing countries, I learned that there are a hugh number of people not able to reach prosthesists.
Let alone being able to get a check up every year. This design is made for these people.
My inspiration was "Where there is no doctor" by David Werner ([WWW]

I hope you have time and interest to read about this prosthesis.
If you could help me take my project a step further, I can't thank you enough!

Thanks in advance,

Inne ten Have
The Netherlands

Lego Team Makes Prosthetic Swimming Arm

Hi, my name is Seamus McAvoy. I am 12 years old, and a member of a First Lego League robotics team called the Future Imagineers. We are team of five boys from both Camas, and Hockinson middle schools. This is our fourth year together. I thought you might be interested in our science project this year.
We created a prosthetic swimming arm for Julie Houghtling, who is a nice young lady who wants to swim, but has been missing her left arm since birth. She has recently learned to swim using just one arm, but she would like to use a prosthetic to swim better using both. We recruited the help of some experts in the field of prosthetics to help us make the arm. It turned out amazing! Please see the pictures of the process at the following web site:
Here is the steps we took:
1. We began making a plaster tape cast of Julie’s left arm and a healthy person’s arm of similar size.
2. We inserted a metal pipe into each mold and filled them with liquid plaster.
3. We removed the plaster tape and smoothed the plaster pieces.
4. We heated a sheet of poly-ethylene to 400 degrees and vacuum formed it around the plaster pieces.
5. We cut the plastic off the plaster of the full size arm to created a mold.
6. Insert the socket into the mold at the correct angle and filled it with foam.
7. We removed the outer plastic mold from the foam, filled the imperfections with Bondo, and painted the yellow foam white.
8. We heated a sheet of harder plastic (co-polymer) and vacuum wrapped the arm with it.
9. We tapped the metal pipe with a hammer which broke the plaster out of the socket.

Useful Links and Tools

Information for People Flying with Prosthetic Limbs and Other Assistive Technology

Traveling on the airlines and making your way through TSA checkpoints can be a confusing process. Come and help others navigate it by sharing your experiences with specific airlines and with TSA on our page TSA and Airline Policies on Prosthetic and Assistive Technology.

A Company or Product Here

Please use this space to help us inform users and volunteers about useful tools that might be helpful as they work on projects. These might be electronic components, general use hardware with application to prosthetics, or the like. You can create a page with more information beyond the brief description on this page.

University of Washington Ph.D. student Scott Saponas demonstrates his muscle-movement interface for computer system: [WWW]


Suggested Projects

We'll look here as well as in the [WWW]Pimp My Arm section for ideas.


Post whatever information you choose about yourself, how you can be contacted, and what you're interested in working on. The bio information in Google Groups may be another way to make contacts, but a little organization might help, and there doesn't seem to be an obvious way to organize group members by interest [post solution here.]

Feedback on Collaboration Tools

We'd like to know what you think of this collection of collaboration tools.


Maintained here.

This is a Wiki Spot wiki. Wiki Spot is a 501(c)3 non-profit organization that helps communities collaborate via wikis.