Children with bilateral cerebral palsy use their hip joint to complete a step-up task

Area of Science:

• Biomechanics
• Pediatric Rehabilitation
• Neuromotor Control

Background:

• Stair climbing is crucial for mobility and community participation in children with cerebral palsy (CP).
• Understanding the specific motor impairments in bilateral CP during stair ascent is vital for addressing mobility limitations.
• The initial step of stair ascent offers sensitive insights into movement quality in pediatric populations.

Purpose of the Study:

• To quantify lower limb joint moments during the stance phase of a step-up task in children with bilateral CP.
• To compare these moments and their timing between children with bilateral CP and typically developing (TD) children.
• To identify underlying motor control factors contributing to stair climbing difficulties in bilateral CP.

Main Methods:

• Seven children with bilateral CP and seven TD children participated.
• Participants performed multiple step-up trials in a university gait laboratory.
• Key outcome measures included peak extensor support moments, hip abduction moments, and their temporal coordination.

Main Results:

• Peak support and hip abduction moments were comparable between the bilateral CP and TD groups.
• Children with bilateral CP exhibited closer timing of peak moments.
• The bilateral CP group demonstrated increased reliance on hip joint moments, particularly in the more affected limb.

Conclusions:

• Despite similar peak joint forces, altered moment timing and increased hip dependence in children with bilateral CP suggest challenges with selective voluntary motor control (SVMC).
• These findings illuminate potential causes for stair climbing difficulties in children with CP.
• Strengthening lower limb muscles may offer a viable treatment strategy for improving stair climbing ability.