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Global Translational Medicine BCI-FES with static magnetic field in SCI

connecting the brain to the paralyzed muscles through affected region. This cortical reorganization causes a
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surface functional electrical stimulation (sFES). Following disconnection from the body representation, turning
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a SCI, the body undergoes molecular changes. Therefore, a command such as “extend your leg” into a challenging
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the implementation of physical rehabilitation techniques activity as the individual is unable to comprehend the
is essential to facilitate neuroplasticity, leading to clinical process and lacks the neural circuit necessary for it. This
improvement in the individual. 6 integrated neuromodulation technique, such as sFES and
The quadriceps femoris muscle is located in the anterior transcutaneous spinal cord stimulation in a pool, has
thigh region. It is innervated by the femoral nerve (lumbar shown initial motor results. 16
plexus/L2 – L4), with hip flexion functions, mainly knee Scientific evidence suggests that the motor imagery
extension. Knee extension is essential to remaining process activates sensorimotor regions similar to actual
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upright, allowing greater autonomy and independence task performance and that repeated practice of motor
in activities of daily living. Injuries to the spinal cord at imagery can induce plasticity changes in the brain. Some
or above the lumbar level compromise activation of the researchers reiterate the potential of this technology,
quadriceps femoris muscle, negatively impacting the suggesting that it can promote neuroplasticity and motor
individual’s level of independence. recovery by applying Hebb’s law, rewarding cortical

Functional electrical stimulation has demonstrated activity associated with sensorimotor rhythms through
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widespread success in treating several clinical cases, the use of a variety of self-guided or assistive modalities.
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especially SCI, with a significant incidence in the world Osuagwu et al. compared NES-FES and sFES interfaces
population. This therapy contributes to improving in the motor rehabilitation of quadriplegic volunteers. The
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muscular trophism and the autonomic system, such as patients were divided into two groups. The participants
the intestinal, vesical, and sexual systems, in SCI patients. of the first group received sessions of FES controlled by a
Facts that enhance the quality of life of people with SCI brain-computer interface (BCI), while the participants of
include functional independence, improved self-esteem, the second group received a manually commanded sFES
and social inclusion. 8 intervention. Neurological assessment measures were: (i)
event-related desynchronization (ERD) during attempted
Conventionally, sFES is applied using commercial movement and (ii) the somatosensory evoked potential
equipment, which allows pre-setting of the stimulation (PEEP) of the ulnar and median nerves. Limb function
current, duty cycle, and frequency; however, they have was evaluated using a range of motion (ROM) and manual
a manual trigger. Recently, the scientific community has muscle testing. The muscle strength of volunteers in the first
been interested in developing research that proposes sFES group improved significantly, whereas those in the second
triggered by surface myoelectric signals (sMES) acquired group showed minor improvements in specific tasks.
through non-invasive electromyography sensors (EMG) Neuromuscular fatigue during the tasks was disregarded
or surface neuroelectric signals (sNES) acquired through in both groups, and small increments were made in the
non-invasive electroencephalography (EEG) sensors. intensity of the sFES (in the open loop) to compensate for
Implementation of this approach reduces spasticity, the reduction in force due to fatigue. The study concluded
contributing to the physical rehabilitation of affected limb that combination therapy with the sNES-sFES interface
movements. 9 resulted in better neurological and muscle strength

Similar to sMES, sNES detects the motor action recovery than sFES alone. For people with SCI, the sNES-
intention of the individual and triggers the sFES to sFES interface should be considered a therapeutic tool for
perform electrically evoked movements. An efficient restoring lost function in individuals with SCI rather than
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strategy for using sNES is event-related desynchronization/ solely a long-term assistive device.
synchronization detection (ERD/ERS). These are Magnetic field (MF) can be applied to the nervous system
sensorimotor oscillatory rhythms associated with motor with a wide range of intensities (4.35 μT – 8 T). Neurites have
imagery (MI), i.e., a mental process by which an individual been proven to grow parallel to the applied MF. Another
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rehearses or simulates a certain motor action. 11 study investigated the intrathecal application of CD133
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Integrated approaches, such as combining stem cells (derived from human blood) in rats associated with the
with intraspinal electrical stimulation, are being evaluated use of a static magnetic field (SMF) with an intensity of 0.6
in animal models. This can be performed using a current T for 30 min. As a result, the group treated with CM and
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intensity below the sensory level to facilitate direct CD133 showed functional improvements after 14 days
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neural growth. SCI causes changes in the organization compared to the group with CD133 without SMF and
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of the somatosensory cortex due to the non-use of the the group with SMF and the application of the phosphate-
Volume 3 Issue 1 (2024) 2 https://doi.org/10.36922/gtm.2285