Most of us take for granted how well our brains can relay instructions to our limbs. Doctors and engineers have been trying for years to grant that same surety to those with prosthetic limbs. But interfacing the biological and technological is tricky. There have been some impressive advances in this area of research, but they usually require the prosthetic to be directly wired into the patient’s brain—not exactly practical. Doctors in the Netherlands are now testing a new type of prosthetic “click-on” arm that is connected to the patient’s existing nerves. It needs a little help from Bluetooth, but the end result is a prosthetic controlled with the mind.
Johan Baggerman from the Netherlands lost his left arm in a 2010 accident, but now he’s one of the first to get a click-on mind-controlled prosthetic. This part of the design isn’t entirely new, but it’s an important part of the overall project. Click-on prosthetics do away with the need for a prosthetic socket that can slip off and cause skin problems. They connect to the body via a metal rod, which is surgically attached to the patient’s remaining bone. A second surgery is needed several weeks later to attach the external section of the rod to the internal one.
The third surgery is where doctors ready the patient to control their prosthetic by thought. A plastic surgeon performs a procedure known as Targeted Muscle Reinnervation (TMR). The nerves that once controlled muscles in the hand are redirected to muscles that still exist in the upper arm. These muscles act as an amplifier for the nerve impulses. So, how do you get those impulses into the prosthetic? That’s where Bluetooth takes over.
After recovering from surgery, the patient has to undergo a period of physical therapy to strengthen the muscles in the upper arm. Eventually, an electrode ring called a myoband is attached to the arm like a bracelet. It detects the impulse in each muscle, then sends the signals over Bluetooth to the small on-board computer in the prosthetic hand. So, if the patient thinks about closing their hand, series of muscles in the upper arm contract instead. The myoband relays that to the prosthetic, which then processes the pattern of muscle contractions as “close hand.”
Only a few patients in the world have received these new mind-controlled robot arms. The prosthetics are expensive and not available widely yet. Eligibility for the procedure will be determined on a patient-to-patient basis when they do become available.
source : https://www.extremetech.com/extreme/248380-new-prosthetic-arm-powered-bluetooth-brainwaves