BCI-Guided Tibialis Anterior FES for Gait Training in Spinal Cord Injury

Introduction:

Spinal Cord Injury (SCI) causes serious motor and sensory deficits, affecting thousands of people globally. Brain-Computer Interface (BCI) combined with Functional Electrical Stimulation (FES) emerges as a promising strategy to rehabilitate individuals with SCI. This mechanism will simultaneously stimulate the affected regions of the lower limbs, causing the compromised muscles to contract, causing movement. The FES technique, with its proven effectiveness in improving muscle strength, stands out as a crucial resource in this process of improving approaches integrated with advanced technology and physiotherapeutic principles to offer a promising perspective in neuromuscular rehabilitation.

Objective:

This study aims to investigate the effectiveness of Brain-Computer Interface (BCI)-guided Functional Electrical Stimulation (FES) in improving muscle activation and gait kinematics in individuals with Spinal Cord Injury (SCI).

Methodology:

This is a quasi-experimental study that will be conducted with four (n=4) volunteers with Spinal Cord Injury (age range: 18-60 years), of both sexes. Data collection will take place at the Edmond and Lily Safra International Institute of Neurosciences (IIN-ELS), Macaíba/RN, Brazil. For the characterization and eligibility of volunteers, the following instruments will be used: Modified Ashworth Scale, Douleur Neuropathique 4 questionnaire (DN4), and the Visual-10, Kinesthetic and Visual Imagery Questionnaire-10 (KVIQ-10). For clinical outcomes, the American Spinal Injury Association (ASIA), Spinal Cord Independence Measure - version III (SCIM-III), and the World Health Organization Quality of Life (WHOQOL-BREF) will be used. At the end of the protocol, the following questionnaires will be administered: System Usability Scale (SUS), Intrinsic Motivation Inventory (IMI), and Task Load Index (NASA-TLX) to assess system usability, intrinsic motivation, and perceived workload. The intervention will consist of 24 sessions aiming to use a brain-computer interface based on kinesthetic motor imagery of dorsiflexion associated with neurofeedback (visual and tactile), focused on the functional outcomes of individuals with paraplegia. During the intervention, volunteers will be instructed to imagine performing the dorsiflexion movement. An electroencephalogram (EEG) will be used to monitor brain activity through sensorimotor rhythms. When activity reaches a minimum threshold, functional electrical stimulation (FES) will be triggered, causing contraction of the tibialis anterior muscle.

Expected Results:

It is expected that BCI-guided FES targeting tibialis anterior muscle activation in individuals with SCI will contribute to the rehabilitation process by promoting improvements in neurological function, functional independence, and cortical activity. Changes are expected in clinical outcomes assessed by the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI/ASIA) and the Spinal Cord Independence Measure III (SCIM III), as well as in EEG patterns associated with sensorimotor cortical activation. Furthermore, this innovative approach will not only provide improvements in the physical performance of individuals with SCI, but will also contribute to the continuous evolution of rehabilitation strategies, highlighting the fundamental role of technological advances in promoting the quality of life and autonomy of these individuals.