Background: Hemiparetic cerebral palsy following perinatal stroke leads to lifelong disability for millions. Assessment of bilateral motor function in real life remains a major challenge. We evaluated the ability of bilateral actigraphy to quantify upper extremity movement in normal and hemiparetic children (1-4). We hypothesized that movement asymmetry would correlate with standard motor outcome measures.

Methods: Thirty hemiparetic and 23 control participants aged 1-18 years wore bilateral wrist actiwatches for 48 hours with movement data collected every 15 seconds. The primary outcome was the Actigraphic Movement Asymmetry Index (AMAI), a novel integrated statistic based on relative difference in left and right hand activity. Relationships between AMAI and standard motor outcome tests Assisting Hand Assessment (AHA) and Box and Blocks test (BB) were explored. Bilateral actigraphy was then prospectively collected from the first ten children in a clinical trial of intensive motor therapy paired with brain stimulation at baseline and 6 months.

Results: The cross-sectional data demonstrated that stroke participants had higher asymmetries compared to controls (mean AMAI 0.818 ±0.08 versus 0.963±0.02 controls) (Figure 1). Correlations between AMAI and standard motor tests were only moderate, strongest for BB (r=0.42, p<0.05). Clinical trial data revealed adequate data collection for 70% with compliance issues identified. Shifts in asymmetry indices were varied but appeared to trend with BB scores.

Conclusions: Standard tests may not reflect movement. Bilateral actigraphy appears to be a valuable, real world measure of motor function during daily life in hemiparetic children. Feasibility within clinical trials requires ongoing study.

References:

1. Kirton A et al. Stroke J Cereb Circ 2013;44:3265–71.
2. Kirton A et al. Lancet Neurol 2015;14:92–102.
3. Kulak W et al. Pediatr Neurol 2004;31:101–8.
4. Michielson ME et al. Arch Phys Med Rehabil 2012;93:1975–81.