Non-invasive brain stimulation may help improve limb function in children with motor disorders following brain injury, such as cerebral palsy or one-sided weakness. This is a relatively safe procedure where pads placed on the head deliver electric or magnetic currents, which are thought to activate the motor areas of the brain.
This review evaluated 14 trials, including 306 children comparing two types of brain stimulation with a control group. It found that these types of stimulation may improve upper limb function, gait and balance. Results were sustained after one month, but we don’t know if there is a long-term benefit
Non-invasive brain stimulation is not routinely used for rehabilitation of motor disorders in children in the UK, though it is used in specialist tertiary centres. This review has the potential to pave the way for further research.
Why was this study needed?
Every year, approximately 40,000 children in the UK experience a brain injury as a result of an accident or illness.
When children experience a brain injury during their earlier years of brain development, it can negatively impact different functions of the body and result in impaired movement, balance and coordination, and loss of muscle strength.
Non-invasive brain stimulation uses two main techniques, transcranial direct current stimulation (tDCS) or repetitive transcranial magnetic stimulation (rTMS). It has received growing interest for its use in the rehabilitation of adults with brain disorders. It is also increasingly being used in children with an acquired brain injury who have subsequently developed movement disorders.
While many aspects of its use in children are still being investigated, these researchers aimed to review existing evidence to evaluate the immediate and long-term effects in the treatment of movement disorders following childhood brain injury and assess the quality of the existing research
What did this study do?
This systematic review and meta-analyses evaluated 14 randomised-controlled trials with 306 participants for the use of non-invasive brain stimulation in children under the age of 18 who had motor disorders following traumatic brain injury or stroke. Most had cerebral palsy or a paediatric stroke. Participants were excluded if they had developed motor disorders due to genetic disease.
Studies of tDCS or rTMS were small, and the treated subjects were compared with inactive treatment control subjects or sham-stimulated subjects. Individual comparisons were often based on fewer than 100 children. The studies were mainly thought to be of adequate quality despite their small size.
The main outcomes of interest were changes in upper limb function, gait, balance and spasticity (muscle contraction). Follow-up ranged from 20 minutes to six months.
The review only included studies in English.
What did it find?
- Upper limb function improved to a large extent with rTMS according to the Assisted Hand Assessment (standardised mean difference [SMD] 0.94, 95% confidence interval [CI] 0.42 to 1.46; 2 studies, 41 children), the Canadian Occupational Performance Measure (SMD 1.30, 95% CI 0.72 to 1.87; 2 studies, 41 children); and the Melbourne Assessment (SMD 1.83, 95% CI 1.20 to 2.47; 2 studies, 32 children).
- Gait improved with tDCS according to steps per minute both immediately after treatment (SMD 0.91, 95% CI 1.01 to 2.12; 3 studies, 64 participants) and after one month (SMD 1.05, 95% CI 0.43 to 1.67; 2 studies, 43 participants). There was no significant improvement in step length or step width.
- Balance moderately improved with tDCS immediately after treatment according to four different measures (range of SMD 0.45 to 0.83; 5 studies, 82 participants), and after one month (range of SMD 0.28 to 0.70; 3 studies, 50 participants) apart from one measure which showed no difference.
- There was no consistent improvement in functional ability such as Gross Motor Function Measure standing (GMFM-D), Gross Motor Function Measure walking (GMFM-E), mobility or self-care. There was insufficient data to determine the effect on spasticity.
- Both types of non-invasive brain stimulation were well-tolerated with very few side effects reported.
What does current guidance say on this issue?
The NICE guideline (updated in 2016) on spasticity in the under 19s recommends physiotherapy and occupational therapy. Orthoses are recommended on an individual basis. Other treatments may include drugs or surgical interventions.
What are the implications?
The review findings support potential consideration for the use of two types of non-invasive brain stimulation in combination with other treatment methods in children with motor disorders following brain injury. The method is non-invasive, relatively safe and appears to improve upper limb function, gait and walking.
There were few trials in each comparison, and each was small. This leads to uncertainty about the size of these effects. More and particularly larger trials may help consolidate these findings and provide an opportunity to test optimal duration, dose and intensity of the treatment with these findings. It might also be possible to clarify the most effective protocol.
Citation and Funding
Elbanna S, Elshennawy S, and Ayad M. Noninvasive brain stimulation for rehabilitation of pediatric motor disorders following brain injury: systematic review of randomized controlled trials. Arch Phys Med Rehabil. 2019; May 9. doi: 10.1016/j.apmr.2019.04.009. [Epub ahead of print].
No funding information was provided for this study.
The Children’s Trust. Who we are. Tadworth: The Children’s Trust Charity; 2019.
NICE. Spasticity in under 19s: management. CG145. National Institute for Health and Care Excellence. London: 2016.
Synapse. Children and brain injury: an introduction. Brisbane: Synapse; 2019.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre