title: A myocontrolled neuroprosthesis integrated with a passive exoskeleton to support upper limb activities.
abstract: This work aimed at designing a myocontrolled arm neuroprosthesis for both assistive and rehabilitative purposes. The performance of an adaptive linear prediction filter and a high-pass filter to estimate the volitional EMG was evaluated on healthy subjects (N=10) and neurological patients (N=8) during dynamic hybrid biceps contractions. A significant effect of filter (p=0.017 for healthy; p<0.001 for patients) was obtained. The post hoc analysis revealed that for both groups only the adaptive filter was able to reliably detect the presence of a small volitional contribution. An on/off non-linear controller integrated with an exoskeleton for weight support was developed. The controller allowed the patient to activate/deactivate the stimulation intensity based on the residual EMG estimated by the adaptive filter. Two healthy subjects and 3 people with Spinal Cord Injury were asked to flex the elbow while tracking a trapezoidal target with and without myocontrolled-NMES support. Both healthy subjects and patients easily understood how to use the controller in a single session. Two patients reduced their tracking error by more than 60% with NMES support, while the last patient obtained a tracking error always comparable to the healthy subjects performance (<4°). This study proposes a reliable and feasible solution to combine NMES with voluntary effort.
authors: NeuroEngineering And Medical Robotics Laboratory, NearLab, Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Italy; Physical Medicine and Rehabilitation Unit, Scientific Institute of Lissone, Institute of Care and Research, Salvatore Maugeri Foundation IRCCS, Lissone, Italy. Electronic address: emilia.ambrosini@polimi.it.
authors: Emilia
authors: E
authors: Ambrosini
authors: NeuroEngineering And Medical Robotics Laboratory, NearLab, Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Italy.
authors: Simona
authors: S
authors: Ferrante
authors: Control Systems Group, Technische Universität Berlin, Germany.
authors: Thomas
authors: T
authors: Schauer
authors: Control Systems Group, Technische Universität Berlin, Germany.
authors: Christian
authors: C
authors: Klauer
authors: Valduce Hospital, Villa Beretta, Rehabilitation Center, Costa Masnaga, Lecco, Italy.
authors: Marina
authors: M
authors: Gaffuri
authors: NeuroEngineering And Medical Robotics Laboratory, NearLab, Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Italy.
authors: Giancarlo
authors: G
authors: Ferrigno
authors: NeuroEngineering And Medical Robotics Laboratory, NearLab, Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Italy.
authors: Alessandra
authors: A
authors: Pedrocchi
mesh_terms: D000328:Adult; D000368:Aged; D001132:Arm / Q000502:physiology; D004550:Elbow / Q000502:physiology; D004558:Electric Stimulation / Q000379:methods*; D004576:Electromyography / Q000379:methods*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D019736:Prostheses and Implants; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013119:Spinal Cord Injuries / Q000534:rehabilitation*; D034941:Upper Extremity / Q000502:physiology
keywords: M-wave; Myocontrolled neuroprosthesis; Neurological disorders; Neuromuscular electrical stimulation; Rehabilitation; Volitional EMG