Correlation of polyelectromyographic patterns and clinical motor manifestations in children with cerebral palsy

Objective: We investigated the correlation between movement patterns, measured by polyelectromyography (PEMG), and clinical motor manifestations in children with cerebral palsy. Design: Subjects included 53 children with spastic cerebral palsy (diplegic [n = 43] and quadriplegic [n = 10] groups) and 18 normal children. All children underwent PEMG assessments, recorded from pairs of flexor/extensor muscles during voluntary movement. We correlated PEMG patterns with clinical motor assessments, including muscle tone, range of motion, and ambulatory and functional capacities in the children with cerebral palsy. Results: Children with cerebral palsy exhibited four distinct PEMG patterns, ranging from partial reciprocal to complete synchrony. Lower PEMG pattern scores were significantly associated with better ambulatory (rho = 0.88, P < 0.01) and functional (rho = 0.78, P < 0.01) capacities. PEMG patterns also had weakly positive relationships with muscle tone (rho > 0.33, P < 0.01) and range of motion of both lower limbs (rho > 0.31, P < 0.01). Most children of spastic diplegia with PEMG patterns II and III had independent ambulatory capacities and mild limitation of functional capacity, whereas most children with pattern of IV and V had no ambulatory abilities and no independent functional capacities (P < 0.01). Conclusions: These findings suggest that PEMG patterns correlate with clinical motor deficits and may allow us to plan treatment strategies based on underlying motor control in cerebral palsy.