World’s First Prosthesis with Direct Connection to Bone, Nerves, and Muscles

Thanks to the electrodes system, a stable signal is obtained, which allows precise control, like handling an egg without breaking it. It also provides sensations as if it were a real hand.
 
The first prosthesis in the world that connects directly to the bone, nerves, and muscles allows the person to experience sensations and free mobility, and is controlled using the mind.
 
Created by Dr. Max Ortiz Catalan, who lives in Sweden, the device becomes an extension of the human body through osseointegration. This means that it connects directly to the bone via a titanium implant, and thanks to the neuronal and muscle binding interfaces, a robust and intuitive control of the artificial hand is achieved. This way, just by thinking about it, the user is able to move the limb.
 
Graduated from the Tecnológico de Monterrey, Dr. Catalan said that Magnus—a patient with an arm amputated above the elbow—is the first person to use the technology. Since 2013, it has allowed him to develop a more normal working life, as he has returned to his activity as the operator of heavy machinery on the border between Sweden and Finland.
 
A doctor in biomedical engineering, Dr. Catalan explained that the electrodes that are connected in muscles and nerves enable stable signals that allow precise control for the patient handling a small, delicate item without breaking it. It also provides sensations as his own natural hand would and is protected from interference such as sensors in retail stores.
 
The research was conducted at Chalmers Technological University in Gothenburg, Sweden, in collaboration with the Sahlgrenska University Hospital, and the implant company Integrum AB, which works with bone anchoring prosthetics.
 
Setting Up
The device consists of two parts, an implant and a prosthesis. The first part requires surgery during which a titanium piece is placed into the bone and a control system that connects electrodes to the muscles and nerves is installed.
 
The second part corresponds to a removable prosthesis that maintains a mechanical connection with the bone and an electrical connection with the implanted electrodes. This robotic component can be taken off so the patient can get wet and take a bath.
 
About 400 people worldwide already have a titanium implant, but only two with the system of electrodes implanted in nerves and muscles. It is expected that this year, more than ten patients will receive the neural control system.
 
New Technology
Technology osseointegration puts an end to inflammation problems, chafing, and discomfort that conventional prostheses cause. “This one strongly presses the stump; it feels like having shoes half a size too small, which is not comfortable. However, by having a direct connection to the bone and not having any components that disturb the skin, the use increases considerably, as well as the quality of life,” said Dr. Catalan
 
Further, as a result of using a titanium implant, the bone is able to grow around it and bind between them, which would not happen with other materials such as stainless steel, which generates a reaction of encapsulation and creates mechanical instability.
 
The titanium implant to anchor the prosthesis to the bone is only available in Europe, Australia, Chile, and the United States, but agreements are being sought to develop it in Mexico.
 
“We aim to make technology that people can use in their daily activities, and we would like it to become a standard treatment for every amputation, thus prices would fall,” concluded Dr. Catalan.