FDA Allows Marketing of First Life-like Prosthetic Arm

The U.S. Food and Drug Administration has approved the marketing of DEKA Arm System, which is the first prosthetic arm that performs several complex tasks.

Last week, the first prosthetic arm that translates signals from person's muscles to perform complex tasks was sanctioned by the FDA.  The multiple simultaneous movements are controlled by electrical signals from electromyogram electrodes (EMG).

The EMG electrodes can identify the electrical activity that occurs when the muscles surrounding the region where the prosthesis is attached, contracts.  The electrodes then transfer the electric signals to a computer processor in the prosthesis that decodes it to a particular movement or movements.

In the newly approved DEKA Arm System, the EMG electrodes translate electrical signals into 10 powered movements and the prosthetic arm is of the same shape and weight as an adult arm.  Apart from the EMG electrode, the newly approved prosthetic arm is a mix of mechanism that includes switches, movement sensors and force sensors that trigger the prosthesis into motion.

"This innovative prosthesis provides a new option for people with certain kinds of arm amputations," said Christy Foreman, director of the Office of Device Evaluation at the FDA's Center for Devices and Radiological Health. "The DEKA Arm System may allow some people to perform more complex tasks than they can with current prostheses in a way that more closely resembles the natural motion of the arm."

 The prosthetic arm was passed after the federal regulators examined the data related to the device including a 4-site Department of Veterans Affairs study in which 36 DEKA Arm System study participants gave inputs on how the arm performed in common household and self care tasks.  The study revealed that nearly 90 percent of the participants were able to perform their activities with DEKA Arm System. They were able to perform those tasks that their current prosthesis failed to so such as using keys and locks, cooking food, feeding oneself, using zippers and brushing and combing hair.

Another advantage of the prosthetic arm is that it can be configured for those who have a limb loss at their shoulder joint, mid-upper arm or mid-lower arm. But this new prosthetic arm cannot be configured for limb loss that occurs at elbow or wrist joint.

The data reviewed by the FDA also included testing of software and electrical and battery systems, mitigations to avoid or restrict unintended movement of arm and hand mechanism. It also included durability testing like the ability of the arm to withstand exposure to common environmental factors like dust and light rain. They also reviewed impact testing.

The device was tested through the nevo-classification process.  It was manufactured by the DEKA Integrated Solutions in Manchester, N.H.