When one loses the use of a limb, it becomes hard to perform even the simplest of daily tasks. However, high-tech devices can help in restoring independence.
FREMONT, CA: Currently, existing prosthetic hands are dependent on weak electric nerve signals in order to know the time they need to activate their motors. The reason is that the electrodes are typically put on the skin over the region where the nerves end at the stump, and the skin does not transfer electricity that properly. Implantable electrodes making contact with the nerves form scar tissue that eventually ruins signal fidelity, and brain-computer is too invasive for most of the applications.
Most recently, researchers at the University of Michigan have figured out a way to give a significant boost to the power of nerve so that when they are captured on the skin, they are robust enough to allow the users to intuitively control them from the first time and with striking accuracy.
Individuals who are presently making use of motorized prosthetic arms need to have knowledge about how to get the devices to do what they want. This can be discomforting and pose a challenge for many people, while the quality of movement is not very accurate. The latest approach enables users to begin using their robotic arms instantly after being fitted with one.
All this is possible because the research team of Michigan was able to manipulate the nerve endings, break apart nerve bundles into smaller fibers, and then implant muscle grafts at the tips of the nerve to serve as signal amplifiers.
The researchers have developed a method for providing individual finger control of prosthetic devices by utilizing the nerves in a residual limb of the patient. With it, they can provide some of the most upgraded prosthetic control.
The scientists encompassed the nerve endings with small muscle grafts called regenerative peripheral nerve interfaces (RPNIs). These enable nerves to penetrate them and grab on, building a robust connection, and preventing neuromas that are responsible for phantom limb pain. Most essentially, when the signal transmitted by nerves reach the RPNIs, the muscle grafts automatically facilitate the electric signal.
The modern approach empowers the users to have control over their prosthetic hand, with single finger precision and also multidegree of freedom thumb movement.