A recent studied examined the use of wrist monitors on 15 children with hemiplegia to study the hypothesis that wrist extension frequency is an indicator of functional hand use. Using video analysis and a wrist monitor that assessed wrist extension frequency, the subjects participated in the Assisting Hand Assessment (AHA). The results indicated that the wrist monitor was reliable to measure frequency of wrist extension. In addition, wrist extension frequency was significantly correlated with the AHA scores.
Reference: Howcroft J, Fehlings D, Zabjek K, Fay L, Liang J, Biddiss E. Wearable wrist activity monitor as an indicator of functional hand use in children with cerebral palsy. Dev Med Child Neurol. 2011 Aug 30. doi: 10.1111/j.1469-8749.2011.04078.x. [Epub ahead of print]