For the first time, a patient has received an implant that allows her to control a robotic hand prosthesis. This is an osseo-neuromuscular implant that connects the patient's nerves and muscles to a robotic prosthesis. The doctors involved speak of the first clinically feasible and daily deployable hand prosthesis that gives patients sensation.
The operation is part of the European DeTOP research project. This project aims to solve the scientific, technological and clinical challenges around restoring hand function after amputation. Within DeTOP, technologies are being developed that provide an interface between humans and next-generation prosthetics.
Horizon 2020
The DeTOP project is funded as part of the European Union's Horizon 2020 programme and is led by Christian Cipriani of the Scuola Superiore Sant'Anna in Pisa, Italy. The project involves a consortium consisting of:
- Scuola Superiore Sant'Anna
- University of Gothenburg
- Prensilia
- Integrum
- University of Lund CSEM
- University of Essex
- Inail Centro Protesi
- University of Rome's Bio-medico Campus
Existing arm prosthesis offer limited functionality
Arm prostheses that can be controlled by the patient have been available for some time. These are so-called 'myoelectric arm prostheses'. Here, arm muscles if tightened transmit electrical signals to electrodes in the arm prosthesis using electrodes glued to the skin. However, these prostheses are known for their limited functionality, controllability and feedback, according to stakeholders. For example, patients cannot feel when their prosthesis touches an object or with what force they grasp it. This is mainly due to the use of surface electrodes, the parties argue.
The DeTOP project aims to increase the usability of such steerable prostheses. The project builds on the 'osseointegrated human-machine gateway' (OHMG), a technology developed by the company Integrum that allows electrodes to be embedded in bone. These electrodes are connected to the nerves previously connected to the amputated limb, enabling a bidirectional connection between the patient and the prosthesis.
Source image: DeTOP project
First implant placed
Previously, Integrum and Chalmers University of Technology showed that using the technology, it was possible to interface with prostheses for amputations above the elbow. However, because two smaller bones are present in the forearm instead of one larger bone in the upper arm, this earlier solution was not usable in the forearm. This earlier technology was therefore further developed into an implant that can be inserted into the forearm to form an interface between the patient and a hand prosthesis.
This implant has now been implanted in a patient for the first time. A total of 16 electrodes were anchored in her bone and connected to nerves in her forearm. The implant was implanted was developed in Sweden by a team led by Dr Max Ortiz Catalan. The development took place at Chalmers University of Technology and Integrum.
Rehabilitation
The patient is currently undergoing a rehabilitation programme to restore strength the bones in her forearm, which have been weakened by not being loaded for an extended period of time. At the same time, the patient is training with Virtual Reality to control a hand prosthesis. In a few weeks, the patient should be able to use the prosthesis during her daily activities.
Author: Wouter Hoeffnagel
Source: DeTOP
