A 21-year-old engineer has successfully created one of the most advanced prosthetic arms we’ve ever seen and for less than $4,000.

Using a 3D printer (and a little help from Microsoft), Easton LaChappelle has been able to build a prototype from scratch for Momo, 9, who is missing her right arm from the elbow down and is one of 30 million people worldwide who need a prosthetic device.

It has been less than two months since the schoolgirl received the finalised device, which looks and feels like a real limb with moving digits, fingernails and the ability to break away from the joint in the event of a fall.

The engineer and the girl had been speaking online for several years about the requirements, before LaChapelle moved to the Microsoft campus in Seattle to get some help from the team in finalising the project.

And it was last month that LaChappelle was finally able to deliver the finished product.

It is not only impressive because the arm is so life-like, but also because it was produced at a fraction of the cost of regular prosthetics, which are normally in the region of $100,000 instead of sub $4000.

Phillip Stevens, President of the American Academy of Orthotists and Prosthetists told HuffPost, that the reason for this phenomenal cost was the need for a “very nuanced prosthetic hand with internal battery systems, multiple microprocessors and multiple individual drive motors” quickly adds up.

Any ability to reduce this cost would not only be important for individuals, but could also have a dramatic effect on the cost of lifetime care for veterans – a study from Imperial College London calculated that the cost of care for amputee soldiers in the Afghanistan conflict was in the region of £228 million.

And now LaChappelle has proved it can be done more cheaply, as well as publishing his own open-source prosthetic designs that anyone can download and 3D print.

The pioneer first came into the spotlight when he designed his first prototype from Lego, fishing wire and basic electrical wiring at just 14-years-old in his bedroom.

His ultimate goal is to make advanced prosthetics accessible for people who need them around the world, regardless of financial barriers.

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