3D printer builds ‘Magic Arms’ for two-year-old girl with joint disease


Detailed within a YouTube video, researchers at Nemours/Alfred I. duPont Hospital for Children developed a lightweight exoskeleton for a two-year old girl named Emma that was born with arthrogryposis multiplex congenita (AMC). The disease can cause joints to become permanently fixed in a single position. Prevalent in Emma’s arms, it was impossible for her to lift her own arms on her own in order to do something as simple as picking up a toy or even giving her mom or dad a big hug. After researching the disease, Emma’s parents attended a medical conference where they learned about the Wilmington Robotic Exoskeleton (WREX). Emma was able to try out a version of the WREX at the hospital, but she was too small for the bulky metal arms.

WREXIn order to design a version for Emma that would both fit her and weigh significantly less, the researchers used the Stratays Dimension 3D printer to build pieces of the arms out of the same type of plastic that’s used in LEGOs. The pieces snap together and resistance bands are used to adjust the tension on the two arms.

In addition, the researchers also developed a jacket that fits over Emma and the arms are fixed to that exoskeleton. This allowed Emma to have increased mobility in her home. She could finally use her arms to do things like color drawings or eat candy as well as simply having fun being a silly kid.

As Emma has grown up, she outgrew the first version of the exoskeleton. However, the 3D printer allows the researchers to input new specifications into a computer program and print larger parts as she grows older. It’s also handy for printing new sections of the exoskeleton when something happens to break. After Emma’s parents send the researchers a digital photograph of the broken piece, the newly printed piece can be dropped in the mail and delivered to Emma’s parents the next day.

When Emma’s parents tell Emma that they are putting on the WREX each day, Emma calls the device her “magic arms.” Researchers have used the design that they built for Emma and have created similar lightweight exoskeletons for other children.