Bionic fingers restore man's dexterity

Until a short time ago, being able to tie his shoelaces by himself would have been impossible for Frank Hrabanek, who lost all four fingers on his dominant left hand in an industrial accident. But two months ago, he was fitted with a prosthesis featuring what are being called the world's first bionic fingers.

Myoelectric sensors inside the elbow-high prosthesis pick up nerve signals from contracting arm muscles, setting the motorized digits in motion — just like natural fingers. 

"I am doing so many things," said Hrabanek, one of just four Canadians and 30 people worldwide to have the dexterity of their hands restored with ProDigits, a product developed by Touch Bionics Inc.

"I can use a fork and knife for eating. It's no problem," the 60-year-old said with a grin. "I can pull my pants on and my socks, because if you have only one hand you're not able to do it."

His wife, Zlata, calls the bionic fingers "a miracle" that have helped return a sense of independence to Hrabanek, who was virtually helpless after his fingers were trapped inside a 500 C die-cast machine in June 2007.

Crushed and burned, the fingers and the knuckles below had to be amputated, leaving him with a mere stump of a hand and one good thumb.

"Frank was like a little kid after the injury," she said of her husband of 40 years, explaining that he had to have everything done for him.

"Now he can do everything himself — eat, cut the meat. He made my dinner two weeks ago.… He can peel the vegetables."

"It's help for both of us. It's not only help for him."

Digits give 'wrap-around grip' 

Rinchen Dakpa, a prosthetist at West Park Healthcare in Toronto who designed Hrabanek's new hand, said before the development of ProDigits, individually powered prosthetic digits for people with a partial hand amputation did not exist.

"Each one of these fingers needs to be individually incorporated into the design of the whole prosthesis," said Dakpa, explaining that although each digit doesn't move independently, they are fine-tuned to work together "to provide a full wrap-around grip."

'I can pull my pants on and my socks, because if you have only one hand you're not able to do it.' — Frank  Hrabanek

Made of a silvery-grey semi-translucent material, the bare ProDigits are certainly robotic in appearance. But Dakpa's lab is working on a cover that can be slipped over Hrabanek's prosthesis that will match the shape and colouring of his other hand, right down to the nails.

"So it actually provides a full body image restoration as well as restoring the function that has been lost."

Touch Bionics, which announced the commercial launch of ProDigits on Tuesday, said prosthetics using the bionic fingers are custom-designed for each patient, who may be missing part of their hands because of congenital anomalies or amputation due to an accident or medical condition.

The Scotland-based company estimates there are about 5,000 Canadians and 1.2 million people worldwide who might be candidates for the bionic fingers. The cost depends on the number of missing fingers, but a prosthetic is estimated to run between $60,000 and $75,000.

"Vocational and social re-engagement is very important to a patient's rehabilitation after a traumatic event," said CEO Stuart Mead. "Partial hand injuries are, by their nature, challenging esthetically and functionally."

Now that Hrabanek is becoming more agile with his bionic hand, he and his wife are looking forward to returning to their favourite hobby — fly fishing.

"That's the miracle," Zlata said of the technology that has helped the couple reclaim their lives. "It isn't any more science fiction; it's a reality."