Transcranial Direct Current Stimulation Versus Virtual Reality on Gait in Children With Spastic Diplegia
Condition: Cerebral Palsy
MeSH terms: Cerebral Palsy
Study type: Interventional

Summary: 
      Spastic diplegia is the most frequent type of cerebral palsy (CP), and impaired gait is a
      common sequela of this condition. The investigators compared the effects of two novel
      research interventions transcranial direct current stimulation (tDCS) and virtual reality
      (VR) on gait impairments in children with spastic diplegia.

      Currently, both tDCS and VR require further investigation to determine their clinical
      effectiveness for children with CP. Thus, the aim of this study was to compare the effects of
      tDCS and VR training on spatiotemporal and kinetic gait parameters in children with spastic
      diplegia, as a supplemental intervention to traditional physical therapy.
    

Detailed description: 
      Cerebral palsy (CP) is caused by early-stage brain injury, affecting 2 to 3 children in every
      1000 live births. CP is divided into different subtypes depending on the dominant
      neurological signs: spastic, dyskinetic, or ataxic. Epilepsy and intellectual disability, as
      well as problems with speech, hearing, and vision, are all common complications [1]. spastic
      diplegic CP is one of the most common developmental disabilities throughout life, caused by
      large-scale changes in subcortical brain activity with a reduced activation of corticospinal
      and somatosensory circuits, which leads to diminished activation of the central nervous
      system during volitional activities.

      Gait impairment is seen in 90% of children with spastic diplegic CP, stemming from this
      decreased cortical excitability and compounded by spasticity of the lower extremities,
      excessive muscular weakness, impaired joint mobility, and poor coordination and balance.
      Specifically, children with CP have reduced gait velocity, cadence, and stride length, among
      other affected spatiotemporal gait parameters. The International Classification of
      Functioning Disability and Health consider changes in the spatial and temporal
      characteristics of gait to be important predictors to poor function and community
      participation. Additionally, crouched gait, scissoring, and other atypical gait patterns are
      common in this population, further affecting the kinematic and kinetic characteristics of
      gait and leading to metabolically expensive locomotion, high fall risk, and long-term
      musculoskeletal injury. For children with spastic diplegic CP, the primary goal of
      rehabilitation is to facilitate mobility and appropriate walking patterns with or without
      external assistance. Improving spatiotemporal and kinetic characteristics of gait would
      improve gait function, increase gait efficiency, and reduce the risk of long-term disability.
      In turn, it would allow these children to participate in more activities of daily living,
      meaningful interactions with family and society, and environmental exploration, as well as to
      improve their physical development.

      In the current study, the investigators considered two technology-driven strategies that
      could potentially target gait impairments and improve gait function in children with CP:
      virtual reality (VR) and transcranial direct current stimulation (tDCS). Both interventions
      have been studied for their therapeutic potential with mixed results, especially in children.
      Specifically, VR can simulate real-life activities while providing repetition, augmented
      sensory input and feedback, error reduction/augmentation to increase motivation during the
      rehabilitation process. As a training tool, VR provides visual perceptual stimulation
      resulting from dynamic changes in context, which may aid in the execution of regulated
      exercises while also requiring concentration and additional postural control. Neuroimaging
      studies suggest that VR can facilitate learning and recovery by stimulating cortical
      reorganization and neural plasticity. Previous research has utilized VR as a therapeutic tool
      for children to improve balance, walking speed, and/or distance, as well as to encourage
      physical activity. Additional VR therapies have been shown to enhance functional performance
      in activities including squatting, standing posture, and energy expenditure. With the
      commercialization of VR-related products like the Nintendo Wii, many virtual games are
      readily available for home use. These games are often designed to challenge and train
      balance, posture, and dynamic movements all of which are critical factors for gait. Thus,
      VR-based rehabilitation may offer a unique, accessible therapeutic approach to reduce gait
      impairments and improve dynamic function.

      In contrast, tDCS is a neuromodulation technique focused on optimizing existing neural
      pathways to prolong and/or improve the functional gains achieved by rehabilitation. tDCS is
      applied through either anodal or cathodal stimulation, which corresponds to excitation or
      inhibition of the stimulated brain areas, respectively. Anodal stimulation enhances cortical
      excitability through depolarization, allowing for more spontaneous cell firing, while
      cathodal stimulation has an inhibitory effect through hyperpolarization. Functionally, this
      means application of tDCS will influence activity in the area of the brain it targets.
      Previous research indicates that inhibited cortical input to the corticospinal tract is a
      possible cause of increased spasticity in CP, so it is reasonable to predict that anodal
      stimulation would mitigate these symptoms in individuals with spastic CP. The
      neurophysiological effects of anodal tDCS can also potentiate motor learning through this
      increase in cortical activity, which is applicable to the treatment of all subtypes of CP.
      These benefits may translate into functionally improved gait as well.
    

Intervention name(s): Transcranial direct current stimulation; Virtual reality
Intervention type(s): Device; Device
Intervention description(s): Transcranial direct-current stimulation (tDCS), over the motor cortex, is a potential therapy option for motor control deficits in children with CP. The application of tDCS involves positioning 2 rubber electrodes sheathed in saline-soaked pads onto the scalp, held in place by a rubber strap. Low-intensity, direct-current, of 1 to 2 mA, is delivered to cortical areas from the device.
The standard-of-care gait training included various gait training and balance tasks as well as resistive exercises and passive stretching as necessary. Task-specific gait exercises included: walking in a closed indoor environment, walking in an open indoor environment, walking on various floor surfaces, and climbing stairs up and down without assistance. The children also performed dynamic balance exercises by walking on a balance board.; Virtual reality rehabilitation is an emerging therapy for motor rehabilitation of children with CP. The therapy is provided through a computer-simulated environment where they interact with real-world-like objects and events through sight, sound, and touch. The Wii Remote was used as the interactive interface, and standard computer/television screens were used as the display hardware. Therefore, VR therapy was of the non-immersive type.
The standard-of-care gait training included various gait training and balance tasks as well as resistive exercises and passive stretching as necessary. Task-specific gait exercises included: walking in a closed indoor environment, walking in an open indoor environment, walking on various floor surfaces, and climbing stairs up and down without assistance. The children also performed dynamic balance exercises by walking on a balance board.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Transcranial direct current stimulation; virtual reality; gait intervention; cerebral palsy