Each finger can be moved separately

April 22, 2008

It can hold a credit card, use a keyboard with the index finger, and lift a bag weighing up to 20 kg - the world's first commercially available pros-thetic hand that can move each finger separately and has an astounding range of grip configurations. For the first time worldwide a patient at the Orthopedic University Hospital in Heidelberg has tested both the "i-LIMB" hand in comparison with another innovative prosthesis, the so called "Fluidhand". Eighteen-year-old Sören Wolf, who was born with only one hand, is enthusiastic about its capabilities.

The new prosthetic hand developed and distributed by the Scottish com-pany "Touch Bionics" certainly has advantages over previous models. For example, a comparable standard product from another manufacturer al-lows only a pinch grip using thumb, index, and middle finger, and not a grip using all five fingers. This does not allow a full-wrap grip of an object.

Myoelectric signals from the stump of the arm control the prosthesis

Complex electronics and five motors contained in the fingers enable every digit of the i-LIMB to be powered individually. A passive positioning of the thumb enables various grip configurations to be activated. The myoelectric signals from the stump control the prosthetic hand; muscle signals are picked up by electrodes on the skin and transferred to the control electronics in the prosthetic hand. Batteries provide the necessary power.

The "Fluidhand" from Karlsruhe, thus far developed only as a prototype that is also being tested in the Orthopedic University Hospital in Heidelberg, is based on a somewhat different principle. Unlike its predecessors, the new hand can close around objects, even those with irregular surfaces. A large contact surface and soft, passive form elements greatly reduce the gripping power required to hold onto such an object. The hand also feels softer, more elastic, and more natural than conventional hard prosthetic devices.

"Fluidhand" prosthetic device offers better finishing and better grip function

The flexible drives are located directly in the movable finger joints and operate on the biological principle of the spider leg - to flex the joints, elastic chambers are pumped up by miniature hydraulics. In this way, index finger, middle finger and thumb can be moved independently. The prosthetic hand gives the stump feedback, enabling the amputee to sense the strength of the grip.

Thus far, Sören has been the only patient in Heidelberg who has tested both models. "This experience is very important for us," says Simon Steffen, Director of the Department of Upper Extremities at the Orthopedic University Hospital in Heidelberg. The two new models were the best of those tested, with a slight advantage for Fluidhand because of its better finishing, the programmed grip configurations, power feedback, and the more easily adjustable controls. However, this prosthetic device is not in serial production. "First the developers have to find a company to produce it," says Alfons Fuchs, Director of Orthopedics Engineering at the Orthopedic University Hospital in Heidelberg, as the costs of manufacturing it are comparatively high. However it is possible to produce an individual model. Thus far, only one patient in the world has received a Fluidhand for everyday use. A second patient will soon be fitted with this innovative prosthesis in Heidelberg.

Heidelberg Orthopedic Workshop provide a unique service in Germany

The workshop at the Orthopedic University Hospital in Heidelberg has been in existence since 1919 and is unique in Germany. Since the Tha-lidomide tragedy in the 1960s it has had its own research department. Today there are some 60 specialized professionals employed in the orthopedic workshop who have learned their trade in many years of training. Every year, around 5,000 patients are fitted with orthopedic aids.
-end-
Contact:

Alfons Fuchs
Director of Technical Orthopedics
Stiftung Orthopädische Universitätsklinik
Schlierbacher Landstrasse 200
69118 Heidelberg
Germany
Phone: +49 6221 / 96 6406
Email: alfons.fuchs@ok.uni-heidelberg.de

Website from „Touch Bionics" about „i-Limb-Hand": www.touchbionics.com/professionals.php"section=5

German press release from the Orthopedic University Hospital in Heidel-berg on prosthetic arms ("Ein Hauch von Science-Fiction" [A Touch of Sci-ence Fiction]) on September 10, 2007:
idw-online.de/pages/de/news224826

Photo 1:
Prosthetic hand "i-LIMB" from the Scottish company "Touch Bionics".
Source: Orthopedic University Hospital in Heidelberg

Photo 2:
Prototype of the "Fluidhand" of the Research Center in Karlsruhe.
Source: Orthopedic University Hospital in Heidelberg

Requests by journalists:

Dr. Annette Tuffs
Head of Public Relations and Press Department
University Hospital of Heidelberg and
Medical Faculty of Heidelberg
Im Neuenheimer Feld 672
D-69120 Heidelberg
Germany
phone: +49 6221 / 56 45 36
fax: +49 6221 / 56 45 44
e-mail: annette.tuffs(at)med.uni-heidelberg.de

Selected english press releases online:
http://www.klinikum.uni-heidelberg.de/presse

Heidelberg University Hospital

Related Prosthetic Hand Articles from Brightsurf:

The biomimetic hand prosthesis Hannes uniquely similar to a human hand
Researchers from Istituto Italiano di Tecnologia and Centro Protesi INAIL in Italy reported on Science Robotics about the prosthetic hand Hannes able to replicate the key biological properties of the human hand.

Phage therapy shows potential for treating prosthetic joint infections
Bacteriophages, or phages, may play a significant role in treating complex bacterial infections in prosthetic joints, according to new Mayo Clinic research.

Engineers design bionic 'heart' for testing prosthetic valves, other cardiac devices
Engineers at MIT and elsewhere have developed a bionic 'heart' that offers a more realistic model for testing out artificial valves and other cardiac devices.

Two chiral catalysts working hand in hand
The stereoisomers of a molecule can cause different effects in a biological system, which is important for the development of drugs.

Prosthetic joint infections missed in patients with rheumatic diseases
Standard diagnostic methods are not adequate to identify prosthetic joint infections (PJIs) in patients with rheumatic diseases, according to findings from a new study by researchers from Hospital for Special Surgery (HSS) in New York City.

Electronic glove offers 'humanlike' features for prosthetic hand users
An electronic glove, or e-glove, developed by Purdue University researchers can be worn over a prosthetic hand to provide humanlike softness, warmth, appearance and sensory perception, such as the ability to sense pressure, temperature and hydration.

3D printed prosthetic hand can guess how you play rock, paper, scissors
A new 3D-printed prosthetic hand can learn the wearers' movement patterns to help amputee patients perform daily tasks, reports a study published this week in Science Robotics.

Tailor-made prosthetic liners could help more amputees walk again
Researchers at the University of Bath have developed a new way of designing and manufacturing bespoke prosthetic liners, in less than a day.

First step towards a better prosthetic leg? Trip people over and over
The first step a Vanderbilt team took in addressing a challenge in lower-body prosthetics was coming to understand the way people with two legs catch themselves, accomplished by covering test subjects with motion-capturing sensors.

Stanford engineers develop a more stable, efficient prosthetic foot
Hiking trails and other rough terrain are especially difficult for people with prosthetic legs.

Read More: Prosthetic Hand News and Prosthetic Hand Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.