Muscle Tone and Stiffness Comparison in Ambulatory Children With Unilateral Spastic Cerebral Palsy: Implications for Postural Balance and Functional Mobility

Abstract

Objectives: To compare muscle tone and stiffness in ambulatory children with unilateral spastic cerebral palsy (UCP) with typically developing peers and explore their relationship with postural balance and functional mobility. Methods: Forty ambulatory children with UCP and age-matched typically developing peers were assessed for tone and stiffness of lumbar spinal extensors, gastrocnemius, and hamstring muscles using a myotonometer. Functional mobility was evaluated with the 2-Minute Walk Test, and the Timed Up and Go Test, while postural balance was evaluated using the Pediatric Balance Scale and the Trunk Control Measurement Scale (TCMS). Results: The gastrocnemius muscle tone and stiffness were higher on the affected side in UCP compared with the less affected side and typically developing peers (P < .05). Lumbar spinal extensor tone correlated with improved Trunk Control Measurement Scale scores (P = .003). The gastrocnemius and hamstring muscles' tone and stiffness did not significantly affect functional mobility measures in UCP (P> .05). Conclusions: Our study highlights the importance of achieving muscle symmetry, particularly in the plantar flexors, for functional mobility in UCP children. While differences in ankle and knee muscle biomechanics were observed, they didn't significantly impact functional mobility or postural balance. Symmetry in lumbar spinal extensor biomechanics correlated with better outcomes, emphasizing the crucial role of trunk control in rehabilitation strategies for ambulatory children with UCP.