Muscle Biomechanical Properties and Postural Control During Static and Dynamic Standing in Children With Spastic Hemiplegia

Cerebral palsy (CP) is a neurodevelopmental disorder that affects muscle tone, posture and motor skills. It is the most common cause of motor disability in infants and children. It describes a group of permanent disorders resulting from non-progressive injury to the fetal or infant developing brain. Although the disorder itself is non-progressive, the clinical manifestations change over time as the brain matures.Children with hemiplegic CP often have difficulty performing voluntary movements due to decreased muscle strength and abnormal muscle tone. As a result, the child are unable to generate the necessary force to maintain their positions against gravity, leading to abnormal posture and balance. Myotonometers are compact, noninvasive tools that swiftly and efficiently gauge the biomechanical characteristics of soft tissues. In typically developing (TD) children, in children with developmental disabilities, and in individuals affected by stroke, it was found to be reliable.Balance is the capacity to preserve equilibrium against gravity during upright postures by maintaining the COM over the center of the BOS. It involves reacting to internal (voluntary movements) and external disturbing forces rapidly and effectively through different postural mechanisms to recover stability. It can be classified into static (maintaining the BOS with minimum movements), and dynamic (maintaining the BOS during different body movements). A comprehensive examination of muscle tone in UCP children can help us understand its impact on motor function and develop more targeted therapeutic interventions.

This understanding can have important clinical implications for treatment efficacy, rehabilitation strategies, and neurophysiological assessments. Addressing muscle tone abnormalities provides a more complete picture of the motor impairments and guides the development of individualized treatment plans, ultimately improving functional outcomes for children with UCP. Therefore, this study aimed to investigate the biomechanical properties, such as muscle tone and stiffness in the lower limb muscles of children with UCP compared with their TD peers. Additionally, investigators explored the associations between these properties and balance control in children with hemiplegia.