Funding: the study was performed as a part of the project “Development of a complex of exoskeleton, hands and procedures for the rehabilitation of children with cerebral palsy” supported by the Ministry of Science and Higher Education of Russian Federation (RFMEFI60519X0186).

Compliance with ethical standards: the study was approved by the Ethics Committee of V.I. Vernadsky Crimean Federal University (protocol № 12 dated June 14, 2016). Informed consent to participation in the study was obtained from the parents.

Author contribution: Kaida AI — data acquisition and analysis, manuscript writing; Mikhailova AA — data analysis, manuscript writing; Eismont EV — research planning, data acquisition and analysis, manuscript writing; Dzhapparova LL — data acquisition, manuscript writing; Pavlenko VB — research planning, data analysis, manuscript writing.