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Updated: Jun 18, 2026
Measurement of Spatial Stability in Precision Grip
Published on: June 4, 2020
Predictive and reactive control of precision grip in children with congenital hemiplegia
Yannick Bleyenheuft1, Jean-Louis Thonnard
1School of Medicine, Université Catholique de Louvain, Brussels, Belgium.
Insights
Children with congenital hemiplegia (CH) show impaired grip force control after impact, affecting predictive and reactive abilities in their paretic hand. The nonparetic hand demonstrates preserved motor control, offering potential for neurorehabilitation strategies.
Area of Science:
- Neuroscience
- Motor Control
- Pediatric Neurology
Background:
- Precision grip relies on coordinated grip force (GF) and tangential load force (LF).
- Children with congenital hemiplegia (CH) exhibit impaired grip control.
- Understanding predictive and reactive control deficits is crucial for rehabilitation.
Purpose of the Study:
- To investigate predictive and reactive control contributions in precision grip among children with CH.
- To compare motor control in paretic, nonparetic, and control hands.
Main Methods:
- Participants (12 children with CH, 10-16 years) and controls performed a precision grip task.
- Object load was dynamically perturbed via a falling mass.
- Conditions included participant-triggered (predictive) and examiner-triggered (reactive) perturbations.
Main Results:
- Grip force levels were similar across paretic, nonparetic, and control hands.
- Predictive control GF timing was altered post-impact in CH hands.
- Reactive control showed longer delays in the paretic hand compared to controls.
Conclusions:
- The paretic hand in children with CH has deficits in both predictive and reactive grip control.
- Altered post-impact predictive control suggests difficulty anticipating dynamic perturbations.
- The nonparetic hand's preserved abilities may inform neurorehabilitation for the paretic side.
Background And Objectives:
Grasping an object between the thumb and index finger requires precise coordination between grip force (GF) and tangential load force (LF), which is impaired in children with congenital hemiplegia (CH). This study aimed to determine the respective contributions of predictive and reactive control in the impaired precision grip of 12 children with CH between 10 and 16 years of age when compared with age- and gender-matched controls.
Methods:
The load of a handheld object was increased rapidly by generating an impact through the drop of a mass attached to the object. The drop was triggered by the participant (predictive conditions) or unexpectedly by the examiner (reactive conditions). In both conditions, participants aimed to prevent the object from falling. Both hands of children with CH and controls were tested.
Results:
During our task, no differences in the GF levels were observed between paretic, nonparetic, and control hands. Under predictive conditions, the temporal variables related to the GF were preserved before impact in children with CH but altered after impact. Under reactive conditions, the reactive delays were longer in the paretic hand. Predictive and reactive control were preserved on the nonparetic hand.
Conclusions:
Deficits were observed in both predictive and reactive control for the paretic hand. The predictive control exists but is altered after the impact, suggesting an inability to anticipate the consequences of a dynamic perturbation. The authors suggest that the abilities of the nonparetic side could be used in neurorehabilitation to improve motor control of the paretic side.
