Quantifying the velocity-dependent muscle response during gait of children with Cerebral Palsy

Area of Science:

• Biomedical Engineering
• Neuroscience
• Pediatrics

Background:

• Cerebral Palsy (CP) often involves spasticity, affecting muscle function during movement.
• Quantifying dynamic muscle response in spasticity is crucial for effective treatment assessment.
• Current methods may not fully capture velocity-dependent muscle behavior during functional tasks like gait.

Purpose of the Study:

• To introduce and validate a novel method for quantifying velocity-dependent muscle response in children with CP.
• To assess the relationship between the new index and clinical spasticity measures.
• To explore the index's correlation with gait parameters.

Main Methods:

• Developed the velocity-dependent muscle activation Index using 3D gait analysis and surface electromyography (sEMG).
• Recruited typically developed children and children with hemiplegic CP (ages 8-19).
• Assessed rectus femoris and medial gastrocnemius muscles, comparing the index with the Modified Ashworth Scale (MAS).

Main Results:

• Higher velocity-dependent muscle activation Index values correlated with higher MAS scores for both assessed muscles.
• Significantly lower index values were found in typically developed children compared to CP groups with MAS scores of 1-5.
• The index showed significantly lower values for lower MAS scores (0-2) compared to higher scores (3-5).

Conclusions:

• The velocity-dependent muscle activation Index effectively quantifies spastic muscle response during dynamic walking in children with CP.
• This index shows promise as an objective measure for assessing spasticity and its management.
• Further research is needed to establish the reliability of this novel index for clinical applications, such as evaluating Botulinum toxin A interventions.