News: a prosthetic hand designed for people with missing fingers has been made available to download from the 3D-printing design database Thingiverse (+ movie).

Dubbed Robohand, the prosthesis was conceived by Richard Van As, a South African carpenter who lost four fingers from his right hand in a work accident.

He got in touch with Ivan Owen, a mechanical props designer from the USA, and the pair designed a set of mechanical fingers printed from plastic with a Replicator 2 desktop 3D printer, donated by Makerbot.

"[The Makerbot] dramatically increased the speed at which we could prototype and try out ideas, and gave us the ability to both hold a physical copy of the exact same thing, even though we were separated by 10,000 miles," says Van As in the movie.

They then tried making a complete hand for a child with amniotic band syndrome, a condition that causes babies to be born with missing or severely shortened fingers.

The resulting Robohand is worn around the wrist and lower arm like a gauntlet and driven by the motion of the wrist.

Bending the wrist forwards causes the cabling to pull the fingers closed, while moving it back releases the fingers.

The digits, knuckle block and wrist hinges are all printed by the Makerbot and joined by cabling and stainless steel bolts, all of which are easy to find and replace.

"With the Makerbot, as [the child] grows, all we do is scale it up and print him another one, and the hardware just gets taken from that and put on the new hand," explains Van As, adding that old hands can then be reused by other children.

The 3D print files for the Robohand are open source and available to print from the Thingiverse website.

Other uses of 3D printing in medicine include a 3D-printed bionic ear that can hear radio frequencies beyond a human's normal range.

We recently reported on the possibility of printing human organs in Print Shift, our one-off publication about the emerging technology – see all 3D printing news or see design for healthcare.