Related Experiment Video
Updated: Aug 8, 2025
The Impact of Motor Task Conditions on Goal-Directed Arm Reaching Kinematics and Trunk Compensation in Chronic Stroke Survivors
Published on: May 2, 2021
Analysis of motor characteristics of reaching movements in children with cerebral palsy
Leia B Bagesteiro1, Tamires L Tellini2, Liana E Brown3
1Department of Kinesiology, San Francisco State University, San Francisco, CA, 94132, USA.
Insights
Children with cerebral palsy (CwCP) exhibit impaired multijoint coordination in both affected and unaffected limbs, showing greater movement distance, duration, and deviation from linearity compared to typically developing children.
Area of Science:
- Neuroscience
- Biomechanical Engineering
- Pediatric Physical Therapy
Background:
- Children with cerebral palsy (CwCP) often experience difficulties with motor control, impacting daily activities like reaching.
- Accurate reaching movements depend on coordinated shoulder and elbow joint actions to guide the hand smoothly to a target.
Purpose of the Study:
- To investigate multijoint coordination during reaching in children with cerebral palsy (CwCP).
- To compare reaching performance between the affected and unaffected limbs of CwCP and control (CTR) children.
Main Methods:
- Speeded reaching movements were performed by CwCP and CTR children using their dominant/affected and non-dominant/unaffected limbs.
- A motion tracker assessed movement kinematics, including distance, duration, speed, hand-path linearity, accuracy, and joint excursions.
Main Results:
- CwCP demonstrated longer movement distances, increased duration, larger shoulder/elbow rotations, and greater hand-path deviation than CTR children.
- CwCP exhibited significantly higher variability in most measures compared to CTR, except for movement duration.
- Distinct shoulder and elbow coordination patterns in CwCP suggest increased reliance on proximal muscle control.
Conclusions:
- Children with cerebral palsy (CwCP) display coordination deficits in both limbs, impacting reaching performance.
- The observed coordination patterns in CwCP may indicate altered neural control, potentially involving the cortical-spinal system.
- Findings highlight the need for targeted interventions to improve motor coordination in CwCP.
Abstract:
Studies confirm that children with cerebral palsy (CwCP) have difficulty with simple, everyday movements like reaching for objects. Accurate reaching requires that shoulder and elbow joints are coordinated to move the hand along a smooth path to the desired target location. Here we examined multijoint coordination by comparing reaching performance in the affected and unaffected limbs of CwCP (nine children, six girls and three boys, aged 8-10 years) to reaching performance in the non-dominant and dominant limbs of typically-developing age- and gender-matched control (CTR) children. The hypothesis was that CwCP would show the effects of coordination deficits in both their affected and unaffected limbs. All children performed two sessions (one session with each arm) of speeded reaching movements to three targets arranged to manipulate the required pattern of shoulder and elbow coordination. The movements were tracked with a motion tracker allowing us to assess the following measures: movement distance, duration, and speed, hand-path deviation from linearity, final position accuracy and precision, and measures of shoulder and elbow excursion. We found that CwCP made reaches that covered a greater distance and took more time, that their shoulder and elbow rotations were larger, and that their movements showed greater deviation from linearity than the movements performed by CTR children. Children with CP were also more variable than CTR children on every measure except movement duration. The pattern of shoulder and elbow rotation observed in the CwCP group represents a coordination pattern that is significantly different from the pattern used by CTR children and may represent a greater reliance by CwCP on proximal muscular control systems. The discussion section considers the role that the cortical-spinal system may play in multijoint coordination.
