Revolutionizing Prosthetics with 3D Printing

The medical device industry is often at the forefront of technological adoption, and for good reason.  If a new technology can help one person in the short-term, then that advance can often be expanded to help many more people in the future.  Additive manufacturing (AM), or 3D printing, is one technology showing great potential in the medical device industry. And one company looking to capitalize on AM’s potential, is Unlimited Tomorrow with its TrueLimb prosthetics. The company was started by Easton LaChappelle, who, at age 14, created a robotic arm for $300 from household items. But the real spark to innovate came after he learned that many traditional prosthetics were no more than simple pinching devices with very high price tags. Furthermore, studies show that more than half of traditional prosthetic owners do not wear them, often due to fit or comfort issues. This is especially a problem for children because the long lead times to get a prosthetic often mean child users only have an individual prosthetic a short while before it is outgrown.

 

Additive manufacturing turned out to be the key solution to these problems. It provides the ability to produce small lot sizes effectively, the ability to manufacture the complex geometries associated with organic forms, and it enables much more rapid manufacturing cycles to get patients their new limb as quickly as possible. By accelerating the delivery time and making prosthetics more comfortable and functional for the user, Unlimited Tomorrow is looking to improve adoption rates dramatically. To achieve that goal, Unlimited Tomorrow asked for help from Siemens Software to automate product development and to scale their operation.

Streamlining Custom Design and Production

Providing a comfortable fit for a prosthetic is a difficult task for adults who have stopped growing, and a constant struggle for children who continually outgrow their prosthetics.  Paying $80,000 for a prosthetic a child may only use for a few months before outgrowing it is a heavy lift for many families with child amputees. 

TrueLimb is Unlimited Tomorrow’s answer to these problems. It is the industry’s first lightweight, realistic, multi-articulating prosthetic limb, all at a tenth of the cost of traditional solutions. Additive manufacturing and modern parametric design have been crucial to the development of TrueLimb because they enable rapid production of the organic geometries associated with human anatomy. This is especially vital in creating the socket that is the human-device interface between the patient and the prosthetic arm. The geometry to design the socket is taken from 3D scans of the patient’s partial limb and the socket is then custom sized and joined to an arm that has been built to the patient’s requirements including skin tone and fingernail choice.

However, designing the geometry of the socket is only one step.  The parts must then be manufactured with great precision. The tight integrations between Siemens NX software and HP 580 color 3D printers allow Unlimited Tomorrow to produce a precise, custom prosthetic for every patient.

Efficiency for Everyone

To provide customers with TrueLimb devices, Unlimited Tomorrow deploys a direct-to-customer approach enabling an efficient ordering and customization process for patients. Customers can undertake the entire process of obtaining a custom prosthetic without ever leaving the comfort of their home. They first submit a 3D digital model of their limb captured in their home using a tablet with specialized software and hardware. Then they can select the skin tone and fingernails to guide arm design. This streamlines the order and fitting process immensely, compared to the traditional process for prosthetics which often require multiple appointments and possible travel to see specialized physicians.

Siemens software helped Unlimited Tomorrow make the entire process as efficient as possible with improved modeling capabilities.  Designing a comfortable custom prosthetic at scale was a tall order for standard CAD design tools requiring large amounts of re-design and multiple trials to obtain a comfortable fit.

It was obvious that a process like this at the scale of Unlimited Tomorrow’s ambition would have been unsustainable. Therefore, Siemens and Unlimited Tomorrow worked together to improve the workflow using software from Siemens like NX and Product Template Studio to combine automation with rule-based parametric design. This gave the team more control over the design of each custom prosthetic, with much less overhead. The simplicity of this improved interaction between patient and provider opened the door to scale the business beyond what Unlimited Tomorrow’s engineering team could handle on their own.

Scaling for the Future

Unlimited Tomorrow has ambitious goals for the future, and that includes getting prosthetics to as many patients as possible worldwide. This scale of production requires a much wider network of specialists to create the custom fit for every patient. Hiring thousands of specialist engineers to work with patients for socket fitting would bloat the cost of TrueLimb, defeating one of the main goals of the effort.

Instead, Unlimited Tomorrow is working on a simple interface using the power of Siemens software to empower clinicians to modify and customize the sockets for patients. This solves the problem of scalability by allowing medical professionals, without extensive training in engineering or product design, to properly fit a prosthetic.  This simplified workflow allows clinicians to make necessary changes to the prosthetic for fit and comfort without needing to directly manipulate the underlying geometry. 

Success with Additive

Additive manufacturing is a powerful tool for creating personalized devices that are literally an extension of the human body. The ability to create the complex shapes that perfectly complement a human user is a great benefit but being able to create them faster and at a fraction of the cost is life changing. Unlimited Tomorrow is doing amazing work pioneering the use of AM in fully customized products and its work with Siemens Software on expanding the accessibility to the design tools, shows a commitment to providing their technology to as many people who need it as possible. The future for Easton and Unlimited Tomorrow is bright, and that’s good news for millions of amputees globally.

For more information on Siemens Digital Industries Software products and services, visit www.sw.siemens.com.

Ashley Eckhoff has a background in engineering and has been with Siemens for over 20 years in various capacities. He has spent the past few years deep-diving into additive manufacturing in both product design and marketing roles.