Award-winning academic and mechanical engineer Dr George Vicatos and his Master’s student at the University of Cape Town, Severin Tenim, designed the hand and sent the plans to the Centre for Rapid Prototyping and Manufacturing at the Central University of Technology (CUT) in Bloemfontein.
“We ‘printed’ each of the little parts individually before we sent it back to Cape Town, where it was assembled,” said centre director Gerrie Booysen.
The 3D hand (Dirk Lotriet, News24)
The result is a mechanically operated prosthetic hand that offers a much more affordable option than anything already available, which makes it perfectly suited to the South African public health sector. The Bloemfontein-built prototype has been exhibited at expos and was well received.
According to Booysen, the hand is undergoing evaluation by medical experts.
“A patent application has already been filed,” he told News24. “There has been a lot of interest in the new artificial limb.”
Project engineer Johan Els explained the fascinating building process to News24 at the CUT offices.
A “sacrificial part” is “grown” in polystyrene, using advanced 3D printing technology. This part is covered with a ceramic slurry. The polystyrene piece is then melted away, leaving a cavity in the ceramic which is perfectly suited for pouring a range of materials – nylon in the case of the hand.
The engineers are extremely experienced at building medical designs. In fact, they had to limit the time spent on the interview because they were busy with another project at the time – “growing” heart valves. At the same time a patient was in theatre receiving a new jaw which was manufactured at the centre.
“The hand has been named ‘the Tenim Hand’ in honour of Severin Tenim,” Booysen said. “Tenim and Dr Vicatos won the ‘Cutting Edge’ award for this hand at the last Popular Mechanics annual FutureTech Conference.”
Vicatos has a passion for medicine and often works with orthopaedic surgeons and oncologists. Hundreds of his other designs have been implanted in patients during operations in South Africa and India.