Integrating Rehabilitation Knee Orthosis and FES-Feedback System for Isometric Training Protocols

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Neuroprosthetics

Background:

• Previous research established foundational work for FES and orthosis integration.
• Current rehabilitation systems require enhanced user integration and adaptive feedback mechanisms.

Purpose of the Study:

• To investigate the integration of functional electrical stimulation (FES) with a portable knee orthosis equipped with a dynamometer.
• To enhance user integration, validate structural improvements, and implement a closed-loop FES feedback system for adaptive rehabilitation protocols.

Main Methods:

• Developed a portable knee orthosis with integrated dynamometer and 3D-printed components.
• Implemented a closed-loop control system for real-time FES signal adaptation based on biomechanical knee torque and muscle response.
• Conducted experimental trials with a non-impaired subject to assess system integration, structural integrity, and FES-induced contractions at varying current levels (40-44 mA).

Main Results:

• Demonstrated successful integration of the FES system and knee orthosis, with the structure withstanding mechanical stress.
• Higher FES currents (40-44 mA) led to increased torque production and faster response times.
• Observed earlier onset of muscle fatigue with higher FES currents, indicating a need for parameter optimization.

Conclusions:

• The integrated FES and knee orthosis system shows potential for improving rehabilitation protocols for individuals with lower limb impairments.
• The system may also serve as a valuable tool for strength training in healthy individuals.
• Future modifications should focus on optimizing stimulation parameters and addressing muscle fatigue during training.