Mechanical work, kinematics, and kinetics during sit-to-stand in children with and without spastic diplegic cerebral palsy

Abstract

Background: Sit-to-stand (STS) is one of the most common fundamental activity in daily life. The pathology of the neuromuscular control system in children with spastic diplegic cerebral palsy (SDCP) could contribute to atypical movement patterns leading to the inefficiency performance including the STS task. However, there was also a lack of evidence about kinematics, kinetics, and especially mechanical work during the STS task in children with SDCP aged 7-12 years old.

Research question: What were the differences in mechanical work, kinematics and kinetics during STS task between children with SDCP and typically developing (TD) children?

Methods: Eleven children with SDCP (GMFCS I-II) and eleven age and gender-matched control TD children with an age range of 7-12 years were enrolled. Motion analysis and force plate systems were used to collect data. All participants performed the STS task from an adjustable chair. Independent sample t-test and two-way analysis of variance were used in this study.

Results: The children with SDCP took a longer time and used more mechanical work during STS than TD children. At the beginning of the STS task, children with SDCP showed more trunk flexion and posterior pelvic tilting; in addition, during the STS task they also presented more trunk, hip, and knee flexion than TD children. However, the children with SDCP showed less ankle dorsiflexion compared with TD children. For the kinetic variables, asymmetry was found in children with SDCP. The maximum hip and knee extension moment, plantar flexion moment, and peak vertical ground reaction force (GRF) of the non-dominant leg were higher than the values of the dominant leg in these children.

Significance: Even though, children with SDCP who are able to independently STS. They were also a mechanically less efficient performance during STS task. Therefore, this task still needs to be trained during rehabilitation sessions.

Keywords: Cerebral palsy; Children; Kinematics; Kinetics; Mechanical energy; Sit-to-stand.