Mechanical work, energetic cost, and gait efficiency in children with cerebral palsy

Area of Science:

• Biomedical Engineering
• Pediatric Orthopedics
• Rehabilitation Science

Background:

• Increased energy expenditure during walking is common in children with hemiplegia.
• The underlying reasons for this elevated energy cost remain unclear.
• Understanding these origins is crucial for effective rehabilitation strategies.

Purpose of the Study:

• To investigate the origin of increased energy expenditure in children with cerebral palsy (CP) during walking.
• To simultaneously assess total mechanical work and work production efficiency.
• To elucidate the relationship between segmental impairments and energy cost.

Main Methods:

• Instrumented gait analysis was performed on 20 children with spastic, hemiplegic CP and dynamic foot equinus.
• Kinematic, mechanical, and energetic variables were analyzed.
• Comparison was made with healthy children to quantify differences in energy cost and mechanical work.

Main Results:

• Children with CP showed a 1.3 times greater energy cost of walking compared to healthy children, despite high Gross Motor Function Measurement scores.
• The increased energy cost was attributed to a rise in total positive mechanical work performed by the muscles.
• No significant decrease in the efficiency of work production was observed.

Conclusions:

• Segmental impairments, such as foot spastic equinus, significantly increase the mechanical work and energy cost of walking in children with CP.
• These impairments contribute directly to the functional disability experienced by these patients.
• A comprehensive evaluation integrating clinical examination, gait analysis, and mechanical/energetic assessments is vital for managing children with CP.