Enhancing functional abilities and cognitive integration of the lower limb prosthesis

Area of Science:

• Neuroscience
• Biomedical Engineering
• Rehabilitation Medicine

Background:

• Lower limb amputation (LLA) disrupts sensory communication, leading to falls, reduced mobility, and poor prosthesis embodiment.
• Current prosthetic devices lack sensory feedback, increasing amputees' cognitive burden and risk of device abandonment.

Purpose of the Study:

• To develop and evaluate a leg neuroprosthesis that provides real-time tactile and proprioceptive feedback to transfemoral amputees.
• To assess the impact of restored sensory feedback on mobility, fall prevention, prosthesis embodiment, and cognitive load.

Main Methods:

• Developed a leg neuroprosthesis delivering tactile and emulated proprioceptive feedback via nerve stimulation.
• Tested the neuroprosthesis in three transfemoral amputees during active tasks.
• Assessed prosthesis embodiment using phantom limb perception and questionnaires.
• Measured cognitive effort using electroencephalography during a dual-task paradigm.

Main Results:

• The neuroprosthesis improved mobility, fall prevention, and agility in transfemoral amputees.
• Enhanced prosthesis embodiment was observed through phantom limb perception and subjective reports.
• Reduced cognitive effort was demonstrated during dual-task activities.
• Induced sensory feedback was integrated at supraspinal levels, restoring functional abilities.

Conclusions:

• Sensory-enhanced leg neuroprostheses can restore functional abilities and improve quality of life for amputees.
• This technology paves the way for advanced, fully implantable neuroprosthetic solutions.
• Further research into brain interpretation of artificial feedback is warranted.