Grant: Operating Grant

Perinatal (around birth) stroke is devastating, because it permanantly affects a child for life. Almost all such children are diagnosed with cerebral palsy (CP), the most common cause of physical disability in children, of which approximately 70% have walking problems. Symptomatic treatment involving bracing, Botox injections, and/or surgery is the current norm, executed after the problems emerge, and is of limited efficacy. Recent studies in kittens have shown that weakened brain pathways, similar to those in perinatal stroke, can be strengthened through intensive training at an early, CRITICAL PERIOD when the developing nervous system is most plastic, thereby restoring lost motor function. Surprisingly, intensive motor training during a critical period of nervous system development (estimated to be < 2 yr of age) is not a part of current therapy. Most CP children in Alberta receive leg therapy only ~1x/mo, starting around 2 yr of age. Thus, we ask if intensive leg therapy to improve walking produces better short- and long-term effects when applied DURING (< 2 yr old) vs AFTER (> 2 yr old) the critical period, and compared to when there is no intensive training at all. A randomized controlled trial (RCT) is needed to answer this question; this study establishes the ground work for such an RCT. Children with perinatal stroke from the two age groups will be trained to step on a motorized treadmill and to initiate movements with the impaired leg (kicking, climbing stairs, etc.) for 1 hr/day, 4 day/wk for 3 mo. We will compare their change in walking and leg function over the 3-mo training period to that of same-age children who receive standard treatment, and we'll track them at 4 yr of age. We will also use electrophysiological measures of the children to understand how the training affects neural pathways. This study will set the stage for an RCT to establish the neural mechanisms, efficacy and optimal timing of intensive leg training after perinatal stroke.