In the back of a room at the Royal University of Fine Arts, a 3D printer hums as it makes a black, plastic thumb. Once finished, the thumb will join four other fingers, knuckles and all, which will be joined to a hand, a wrist and an arm. All of this originates from inside two printers, illuminated boxes the size of microwave ovens with the label “Ultimaker”. Within 48 hours, the printers can make all the components of a prosthetic arm.
Soon, the entire limb will have a new home, with one of a group of amputees in Siem Reap Province in line for new prosthetic arms. For the first time since losing their arm, or maybe for the first time ever, the recipient will be able to control their hand and to perform the tasks that most people take for granted – to hold and write with a pen, to use a spoon or a fork and to wash the dishes.
The prosthetic arms were designed by engineers at the Victoria Hand Project, an NGO housed at the University of Victoria in Canada. VHP has been working in Cambodia with Arc Hub Pnh, a 3D-printing lab founded and run by brothers KiHow Tran and Ki Chong Tran. Last week, Arc Hub Pnh, VHP and the Siem Reap Physical Rehabilitation Center (PRC) fitted their first three clients with the prosthetic arms, and they hope that a total of 25 amputees working with PRC will be using them by the end of November.
Unlike the more common hook prostheses, the VHP design actually resembles a hand in shape, and it performs like one as well. A taut cord similar to a bicycle brake cable connects the fingers to a harness that is attached to the back. When the client moves his or her shoulders, the hand either clenches or loosens its grasp. If someone wants to hold a pen, for example, they can “lock” their fingers in place so that they don’t drop it. The hand connects to the wrist with a “ball and socket” design, which makes the angle at which it bends adjustable.
Brothers KiHow (left) and Ki Chong Tran (center) and VHP’s Angie MacDonald. KT/Fabien Mouret
“The lead researcher designed this mechanical hand in the 1990s with ‘adaptive grasp’, as we call it, meaning the fingers are able to form around shaped objects,” explains Angie MacDonald, an engineer at VHP. At the time, the prosthetic was too expensive for practical use, so the idea more or less had to wait until 3D printing came along. Now, the total cost of one prosthetic, including labor costs, is just $325.
“There’s a huge need for people who can’t afford traditional prostheses,” MacDonald says, adding that a traditional “hook” prosthesis can cost between $3,000 to $15,000.
Most estimates put the number of amputees in Cambodia at over 40,000 – the harsh legacy of war and of a countryside still cleaning up landmines. The government has supplied amputees with “cosmetic” prostheses on request, but these are more for appearance than for practical use.
The 3D-printed model can replicate much of the natural function of a hand and do so at a reasonable price. One challenge, KiHow says, is for patients to feel comfortable enough to use them. “The thing about Cambodians is that they really want to fit in. They don’t want to look that different,” he says. “Although [the prosthetic arm] is different they realize that it’s super functional. They can use it for different things.”
At the recent fitting, Tran watched the patients’ comfort level evolve. In one case, a 19-year-old woman started off hesitant, but when she grew accustomed enough to it to write with a pen she was convinced. “We had to take it off to make a few adjustments, then when she put it back on she was grabbing everything,” MacDonald says.
“We couldn’t stop her at that point!” KiHow says, laughing.
“Most of the clients had an amputation and thought they could never use that limb again. With this prosthetic they are able to do different things. I think after they saw that they got over how it looked.”