Getting from 3D scan to 3D print: computer-aided prostheses and orthoses

Orthopedic technology is a true craft: That's because prostheses and orthoses are rarely off-the-shelf products. Orthopedic technicians must typically use different materials to custom create and fit the devices. Many of these processes are manual. For several years now, 3D scanning and 3D printing have modernized the industry thanks to digital design freedom and flexible production.

"The technicians use plaster to create molds of body parts and they use tools to create their products. Young specialists do not want to work in this environment that does not look like high-tech and medicine very much." This is how Andrei Vakulenko, Chief Business Development Officer at Artec 3D, sums up the old notion of orthopedic technology in a MEDICA-tradefair.com.de interview. Artec 3D produces a variety of professional 3D scanning solutions that benefit orthopedic technology.

"You can scan a part of the body from all angles, just like you would with a camera, to receive a mesh, a digital model of the body part," he details the process. This model can be edited with design software to create the template for a specific device. "The model can then be sent to a manufacturer, or it can be printed directly using a 3D printer."

Functional prosthetic limbs and orthoses are not the only devices that 3D scanning and 3D printing are able to create. Cosmetic prostheses – an ear prosthesis, for example – can also be custom made via the same technology. Here, the still existing body part is scanned and mirrored to create an exact replica for the deformed ear on the other side of the body. The prosthetic devices look very realistic and lifelike thanks to the modern, high resolution scanners.

As a form of measurement, 3D scanning is not exactly a novel technology in orthopedics. It is a popular tool to analyze a patient's gait pattern, to detect misalignment and measure the stress on the sole of the foot. However, the next production steps after the diagnosis are still predominantly analog – including custom insoles made by hand and adjustments done by the orthopedist or orthopedic technician. 3D printing production makes orthopedic technology fully digital and gives the creation of assistive devices a never-before-seen boost.

"3D printing makes it possible to tailor shapes, functions and material thickness to meet each patient's specific needs. The traditional manufacturing process often reaches its limits when it comes to complex structures. The production is also a time-consuming and costly process – but meanwhile patients want quick availability," explains Thomas Rockenbauer, CEO and co-founder of Luxinergy GmbH, in a MEDICA-tradefair.com interview. Together with Kerkoc GmbH, Luxinergy is developing a 3D printing process for orthopedic applications that uses biocompatible resin.

"People like to wear 3D-printed orthoses because they can be customized, which also increases the therapeutic effect," Rockenbauer adds. The latter is very plausible, since past generations of prosthetic and orthotic devices were undeniably bulky, unfashionable products. Beautiful, modern design can make it easier to accept the assistive device, especially for adolescents and young people.

The digitization of orthopedic technology not only improves the properties, appearance, and availability of the assistive devices. It also simplifies and improves the orthopedic technician workflow: when they design a digital prosthetic, they no longer need to manually try different materials and create molds, which require several labor-intensive adaptations to fit the needs and dimensions of the patient. Instead, the technicians can create, modify, and save the assistive devices digitally as a file on the computer. If needed, devices can be replicated with accuracy and used as a template.

Digitization also promotes work specialization in orthopedic technology. While an orthopedic technician specializes in customer service, takes measurements, and gives advice, other employees can focus on technology or design and use the measurement data to create the assistive device.

"I believe the future of orthopedic technology is fully digital. Traditional craftsmanship will switch over to newer technologies – and embrace tools like computer-aided design (CAD)," says Rockenbauer.

Somewhere down the road, this will not just change individual work steps, but is going to transform the entire industry if the models are sent to the manufacturer or a central manufacturing company for further processing or production. This division of labor and separation of tasks is smart because not all companies can currently facilitate full digital operation, and the requisite equipment and know-how are also not yet broadly available.

But that could quickly change because "3D scanners will become extremely easy to use. I think that step-by-step we will make the process of 3D scanning easier and more and more useful to people in each area," Vakulenko predicts.