Advances in robotics are paving the way towards prostheses with functionalities similar to their biological counterparts. While the state-of-the-art prostheses are now capable of mimicking fine movements and grips, the level of intuitive control and sensory feedback individuals with amputation have with their prostheses are still primitive.
Researchers recently published the capabilities of our osseointegrated neuromusculoskeletal interface, the e-OPRA™ Implant System. The prosthetic system is developed upon the OPRA™ Implant System which allows direct connection of the prosthesis to the bone. The e-OPRA™ Implant System allows simultaneous connection to bone, muscles, and nerves for long-term home use. This technology, in addition to providing intuitive and natural control, also provides sensory feedback by stimulating the severed nerves.
EXPLORING STIMULATION STRATEGIES
The study titled “Neural Feedback Strategies to Improve Grasping Coordination in Neuromusculoskeletal Prostheses” published in the journal Scientific Reports, explores several neural stimulation strategies and the effects of tactile sensation on hand prosthesis movements while grasping objects. This research is a collaborative work between Integrum, Chalmers University of Technology, Sahlgrenska University Hospital, Sahlgrenska Academy at the University of Gothenburg, Sant’Anna School for Advanced Studies, Prensilia s.r.l, and Medical University of Vienna.
The well-established Pick and Lift Test (PLT) was used to investigate how sensory feedback affects the coordinated movements of neuromusculoskeletal prostheses. In the test, participants were asked to pick and lift an object repeatedly from a table while the execution forces and time were measured. The researchers also randomly changed the weight of the object and collected information on participant reactions to this unexpected change.
In line with other neuroscience studies, the researchers showed the value of touch sensations for prosthetic hands to carry out grasping effectively, specifically under uncertain conditions. They also found that the effectiveness of tactile sensation can be affected by the selected neural stimulation strategy and, by the prior experience of the prosthesis user.