Researchers at the Cleveland Clinic have developed an advanced bionic arm that allows users with upper limb amputations to achieve a similar level of function as non-amputees. The system incorporates a sense of touch and movement and allows for intuitive motor control. The device is intended for users who have undergone targeted sensory and motor reinnervation procedures in which motor and sensory neurons are redirected to the skin and muscles in the residual limb, allowing them to communicate with the bionic limb. Bionic prostheses are advancing apace. This latest device is complex, but boasts impressive functionality. “We modified a standard-of-care prosthetic with this complex bionic system which enables wearers to move their prosthetic arm more intuitively and feel sensations of touch and movement at the same time,” said Paul Marasco, a researcher involved in the study. “These findings are an important step towards providing people with amputation with complete restoration of natural arm function.” While robotic prostheses that feature a sense of touch have been created before, this newest device also includes a sense of movement, so users can feel the sensation of their arm moving through space. This is achieved by small robots that vibrate, activating kinesthetic sensory receptors in the muscles of the residual limb. Becoming more aware of their limb appears to greatly enhance a wearer’s ability to use it. For instance, users were able to perform tasks with their new bionic limb without watching it, just like they would with a regular arm, something that has been difficult for upper-limb prosthetic users before now. “Over the last decade or two, advancements in prosthetics have helped wearers to achieve better functionality and manage daily living on their own,” said Marasco. “For the first time, people with upper limb amputations are now able to again ‘think’ like an able-bodied person, which stands to offer prosthesis wearers new levels of seamless reintegration back into daily life.” The technology is not for everyone, as users must have undergone targeted sensory and motor reinnervation, where a surgical procedure reroutes sensory and motor neurons to the skin and muscles of the residual limb, allowing better communication between the limb and the prosthetic. So far, the device has been tested in two such patients, and their performance with the limb has been impressive. “Perhaps what we were most excited to learn was that they made judgments, decisions and calculated and corrected for their mistakes like a person without an amputation,” said Marasco. “With the new bionic limb, people behaved like they had a natural hand. Normally, these brain behaviors are very different between people with and without upper limb prosthetics.” Source
