Background: Perinatal stroke causes hemiparetic cerebral palsy. Developmental plasticity models have informed central therapeutic targets. Repetitive transcranial magnetic stimulation (rTMS) can modulate motor learning in adult stroke but is untested in perinatal brain injury.

Methods: PLASTIC CHAMPS (www.clinicaltrials.gov/NCT01189058) was a randomized, blinded factorial trial of rTMS and constraint therapy (CIMT) in stroke-induced cerebral palsy. Children 6-18 years participating in a 2 week goal-directed motor learning camp were randomized to inhibitory rTMS (1Hz, 1200 stimulations) over non-lesioned motor cortex, CIMT, both or neither. Primary short-term outcome was 1 week post-camp Melbourne Assessment (MA). Additional outcomes included Assisting Hand Assessment (AHA), Canadian Occupational Performance Measure (COPM), and safety/tolerability. Corticospinal tract (CST) orientation was defined using single-pulse TMS.

Results: All forty-five children completed the trial (median 11.4yrs, 67%/33% arterial/venous, mean MA(SD) 74(23)%). All improved on multiple measures at 1 week. Compared to sham, rTMS was associated with greater gains in MA (5.51(5.9) versus 1.89(4.7), p=0.027). CIMT did not affect 1 week MA. Group comparison suggested greater improvements for rTMS alone compared to CIMT alone (p=0.06). rTMS and CIMT effects did not appear synergistic. rTMS did not decrease function in children with ipsilateral CST projections (MA increased 5.1(4.6)%, p=0.04). Unaffected hand function did not decrease with rTMS or CIMT. Procedures were well tolerated with no serious adverse events.

Conclusions: Non-invasive brain stimulation trials are feasible in children with perinatal stroke. Inhibitory, contralesional rTMS may enhance motor learning therapy in stroke-induced cerebral palsy. Long-term outcomes will help determine clinical relevance.