February 5, 2014

expert reaction to a hand prosthesis equipped with artificial sensors

Science Translational Medicine published the results of a one-man clinical trial of a prosthetic hand that enabled an amputee who had lived without the sensation of touch for ten years to feel differences in the shape and stiffness of objects again.

Dr David Gow, Fellow of the Institute of Physics and Engineering in Medicine (IPEM), and Director of Rehabilitation Engineering Services and Bioengineering, NHS Lothian, said:

“One of the key challenges facing the development of upper limb prostheses is how to control and derive feedback from the increasingly complex devices now available clinically. The work of this Italian team gives a strong indication of the usefulness of achieving such sensory feedback. Although based on a single case study the results look like a practical surgical based method of delivering spatial and force information from a robotic hand’s sensors back to the user to allow him fine control of force and to gain some knowledge of the shape and stiffness of the object in his artificial grasp. This opens up exciting possibilities for artificial limb users and takes us a step closer to a clinically viable man-machine interface.”

Dr Alastair Ritchie, Lecturer in Biomaterials and Bioengineering, University of Nottingham, said:

“This is very interesting work, taking research in upper limb prosthetics into the next stage by adding sensory feedback. Upper limb prosthetics has long been a challenge for bioengineers – our hands are one of our principal interfaces with the world, and in recent years we have seen real advances. This technology would enable the user to know how firmly they are gripping an object, which is vital for handling fragile objects – imagine picking up an egg without any feeling in your fingers. Another exciting aspect is the ability of the human brain to learn, allowing the user to become more proficient as he gains experience in using the prosthesis.

“However, the use of a transcutaneous sensor, with the electrodes embedded next to the peripheral nerves, and wires running through the skin, presents biocompatibility challenges and will require rigorous wound care to prevent infection.”

‘Restoring natural sensory feedback in real-time bidirectional hand prostheses’ by Stanisa Raspopovic et al. published in Science Translational Medicine on Wednesday 5 February 2014.