Researchers have developed a highly integrated bionic arm prosthesis that enables advanced everyday use via implanted electrodes interfacing with the nervous system. An amputee patient has used it successfully for over 3 years.

Under the guidance of Professor Max Ortiz-Catalan, head of the neuroprosthetics department at the Australian Bionics Institute in Melbourne, a team of engineers and surgeons from around the world developed a new type of prosthesis integration, thanks to which the Swedish amputee patient Karen received a bionic prosthesis, almost as functional as the arm she lost in a farm accident. Moreover, it withstands constant daily use for more than 3 years.

For prosthetics, remaining stump muscles provide intuitive control sources by linking their electrical signals during contraction to robot motions. But higher amputations leave fewer muscles to control the required joints.

The new interface implements osseointegration - direct skeletal attachment of the implant. Electrodes inserted in nerves and muscles then connect to the body's nervous system.

"Karen became the first person with an upper limb amputation below the elbow to receive this new concept of a highly integrated bionic arm that can be used independently and reliably in everyday life," Ortiz-Catalan said. "The fact that she has been able to comfortably and effectively use her prosthesis in everyday activities for many years is a promising indication of the potential of this new technology to change the lives of people faced with limb loss."

This complex integration was tailored to the confined space in the forearm. Surgeons positioned the patient's nerves and muscles optimally to convey motor control signals.

The patient can now control the prosthetic much like her missing biological arm using similar neural pathways. Everyday tasks like carrying full cups and zipping jackets are possible with the dexterity provided.

It also reduced her phantom limb pain, which previously required heavy painkiller use. She describes profound quality of life improvements from the solution.

"The biological integration of titanium implants into bone tissue opens up opportunities for further improvement in the care of amputated patients," says Rickard Bronemark, associate professor at the University of Gothenburg and founder of Integrum, a company engaged in the development of biotechnological implants. - Combining osseointegration with reconstructive surgery, implanted electrodes and AI, we will be able to restore human functions in an unprecedented way. The level of amputation below the elbow is particularly difficult, and the level of functionality achieved is an important milestone in the field of modern limb reconstructions in general."

The modular design allowed testing prosthetic arms from two different companies for taking advantage of latest innovations. This person-centric approach resulted in wide adoption.

The successful integration sets an important precedent in extracting rich control from residual nerves and musculature. It hints at future capabilities as neural interfaces and prosthetics continue improving.

"It seemed to me that my hand was constantly in a meat grinder, which created a high level of stress, and I had to take large doses of various painkillers," she says. "These studies mean a lot to me, because they have allowed me to live better."

This collaborative work combines expertise in surgery, neuroscience, robotics, and bioengineering to maximize restoration of function. Such cross-domain efforts are key to translating ideas into patient realities.