Tactile-Sensing Prosthetic Hand

In a first-of-its-kind surgical procedure, doctors have successfully implanted the first clinically viable prosthetic hand that provides not only dexterity but also gives the user sensory feedback. The revolutionary development represents several breakthroughs in implant technology.

While it is not the first controllable prosthetic hand, earlier versions have relied on skin electrodes to pick up signals from underlying muscles, resulting in control of only a few gross movements such as opening and closing the hand. The new technology uses 16 electrodes implanted into the forearm to extract the signals directly from the nerves that used to be connected to the lost hand. This provides more detailed and reliable information for finer motor control and also enables kinesthetic feedback to the wearer regarding things like contact pressure.

It was also the first demonstration of a sentient prosthesis in a below-elbow amputee. While earlier experiments in above-elbow amputees using similar methods had indicated that the concept was viable, the smaller bones of the forearm posed some challenges in the design of the prosthetic. And since bones weaken from lack of use, patients will need to follow a rehab program to build bone strength before being able to fully load the new prosthetic. One benefit of below-elbow implants, however, is the availability of more muscles in the forearm, which helps to achieve greater dexterity.

Two additional patients are already scheduled to receive the new implants in coming months.