This study will evaluate the feasibility of transcranial direct current stimulation (tDCS) as an adjunct to an outpatient motor skills-based physiotherapy intervention for children and youth with acquired brain injury. Up to 10 children (age 5-18 years) with childhood onset stroke or traumatic brain injury will be randomly allocated to receive active or sham anodal tDCS immediately prior to the physiotherapy session. These sessions will occur twice weekly for a total of 10 sessions. Assessment of gross motor outcome measures will occur immediately before and after the combined tDCS and physiotherapy treatment protocol. The preliminary treatment effect between the two treatment groups will be compared and other feasibility indicators will be evaluated.

Objectives: The purpose of this study is to evaluate the feasibility of tDCS as a pre-treatment adjunct to outpatient physiotherapy (our outpatient 'physio+tDCS' protocol) for children with stroke or TBI. The primary objective is to evaluate the feasibility of an outpatient twice weekly 'physio+tDCS' protocol given over five weeks, as measured by participant eligibility, recruitment, tolerance, retention, and adherence to treatment protocol (e.g., session frequency and completion timelines). The secondary objective is to explore the preliminary effect of physio+tDCS on gross motor function in children with childhood onset stroke and TBI, as measured by individualized goal achievement and standardized gross motor outcome measures.

Randomization and Blinding: Once enrolled in the study, an independent research assistant (RA) will randomly assign each child to the "sham" or "active" tDCS treatment group using a computer randomization web-based program. Only the RAs involved in the study will be aware of each participant's treatment group assignment. The participants and the assessing/treating PTs will be blinded to the participant's treatment group.

Intervention:

tDCS Treatment- Depending on treatment group allocation, participants will receive 20 minutes of active tDCS or sham tDCS (provided by a trained RA) immediately prior to two physiotherapy sessions each week for a total of 10 sessions. Children and PTs will be blinded to their tDCS/sham allocation. Two electrodes (5x7cm) in size will be used such that the anodal electrode will be attached to the C3/4 position on the scalp, to target the lower extremity region of the primary motor cortex most affected by their brain injury, and the cathodal electrode will be attached to the contralateral supraorbital (Fp1/Fp2) area of the forehead. Each tDCS treatment will consist of up to 2.0 mA of stimulation, adjusting for the child's age, head size, and tolerance as required. Participant symptoms and safety will be tracked before, during, and after each tDCS session. Adverse events reported via a REB-approved standard process to an independent in-house safety monitoring committee. Physiotherapy Intervention- The physiotherapy treatment paired with the tDCS consists of the typical motor skills-based physiotherapy children receive brain injury program at Holland Bloorview. Each 45-minute physiotherapy session promotes motor learning by focusing on functional tasks related to the child's personalized motor goals. Therapists individualize the program by adapting the tasks, instructions, feedback, and the level of challenge based on the child's needs.

Outcomes Feasibility- Feasibility of study implementation and tDCS will be evaluated by tracking process, resource, and treatment indicators. A priori feasibility targets are as follows: 30% of children indentified by the child's clinical physiotherapist or nurse will be eligible for the study, 70% of eligible children will be recruited; 80% of the tDCS sessions started will last the entire 20-minute duration, 75% of treatment sessions will be completed, and 90% of reassessments will occur in the 14 days following the final treatment session. Adherence to the study protocol will be tracked by the number of tDCS and physiotherapy sessions scheduled per week and the number actually completed. Reasons for cancelled sessions or decreased number of sessions booked will be documented. Because tDCS should optimally occur in the half hour prior to physiotherapy, the start time and duration of stimulation will be documented, as well as the start time and duration of each physiotherapy session, on tracking sheets that will be completed by the RA/therapist conducting each tDCS/physiotherapy session.

Gross Motor- Baseline assessments will be conducted by a blinded independent PT assessor in the two weeks prior to beginning the study treatment protocol. The reassessment will be conducted by the same blinded PT assessor up to two weeks after their last study intervention session. A priori targets for the co-primary gross motor outcomes are as follows: The active tDCS group should have at least 3 mean points of change more than the sham group on the Gross Motor Function Measure (GMFM) and at least 2.0 mean points of change more than the sham group on the Canadian Occupational Performance Measure (COPM).

Inclusion Criteria:

• Stroke or moderate to severe traumatic brain injury, diagnosed with imaging (e.g., MRI, CT scan);
• 5-18 years of age inclusive (at time of study enrolment);
• In the outpatient stage of rehabilitiation
• Followed by a physician through ABI medical follow-up clinic at Holland Bloorview OR previously admitted to the inpatient ABI program at Holland Bloorview;
• Medically stable, as determined by their ABI physician;
• Walks a minimum of 10m with or without assistance;
• Stands independently for 10s;
• Balances for less than 20s on most affected leg;
• Hemiplegia, identified by decreased selective motor control at one ankle compared to the other (i.e., decreased ability to isolate ankle plantar flexion and dorsiflexion on the more affected ankle);
• Available to attend twice weekly appointments for five weeks, as well as a two-hour baseline and post-treatment assessment;
• Tolerates 2 hours of physiotherapy assessment (with short breaks as needed);
• Tolerates 45 minutes of physiotherapy treatment;
• Capable of participating in standardized physiotherapy assessment, from a cognitive and behavioural perspective; and
• Can communicate discomfort either verbally or non-verbally
• Follows directions provided in English
• Parent/legal guardian can read and speak English

Exclusion Criteria:

• Admitted to acute care or inpatient rehabilitation hospital
• Seizure(s) in the last 6 months;
• Planned medication changes during study (i.e., any medication that affects their ability to participate in therapy from a physical, cognitive, emotional standpoint);
• Botox injections in the last 3 months;
• Brain tumour;
• Metal implants or fragments in the head;
• Cranial bone flap removed;
• Stitches/staples on the head;
• Wounds or unhealed incisions at electrode placement sites;
• Cochlear implant;
• Implanted neurostimulator (e.g., vagal nerve stimulator, deep brain stimulator);
• Cardiac pacemaker;
• Battery-powered medication infusion device (e.g., baclofen or insulin pump);
• Pregnancy;
• Diagnosed with another neuromotor disorder(s) affecting gross motor function (e.g., cerebral palsy, spinal cord injury, etc.…);
• Onset of ABI before the age of two years;
• Neurodegenerative diagnosis;
• Lower extremity weight bearing activity restrictions secondary to injuries (e.g., fracture, ligamentous injury) as present at time of study enrollment;
• Non-orthopaedic activity restrictions that limit gross motor activity (e.g., splenic laceration with orders not to run or jump); or
• Enrolment in another treatment-based research study during the current study

At this time data will not be shared with other researchers

Physiotherapists providing treatment, physiotherapists conducting assessment, research coordinator, principal investigators, participants are all blinded to treatment allocation. Research assistants administered the transcranial direct current stimulation are not blinded.