Characteristic of electrophysiological activity of the cerebral cortex in children with arthrogryposis

Background. Arthrogryposis is one of the most severe congenital abnormalities of the musculoskeletal system characterized by 2 or more contractures of the large joints, muscle and anterior grey column pathology. One of the main problems making selfcare limited or impossible for the patients is an absence of the active movements in the joints of the upper extremities which can be restored through autologous trans- plantation from the various donor areas. Processes of the rehabilitation after these operations are associated with neuronal remodeling in the central nervous system both in the spinal cord and the brain, in the cortial regions in particular. The objective is to evaluate possible reflection of arthrogryposis in the amplitude and neurodynamical characteristics of the electroencepha- logram (EEG) in children. Materials and methods. Electrophysiological characteristics of the cerebral cortex in children with arthrogryposis and healthy children of the same age were examined. Such EEG characteristics as power and long-range temporal correlations (evaluation of the neuronal activ- ity dynamics) in ranges of 4–8, 8–12, and 12–16 Hz were measured. The results were evaluated in accordance with clinical scales. Results. Data analysis has shown that children with arthrogryposis have significantly decreased EEG power in all of the studied ranges com- pared to healthy children. Additionally, a significant correlation between EEG power and the level of restoration of motor functions in the upper extremities after autologous transplantation of various muscle groups in the position of the biceps was observed. The obtained results reflect correlation between the electrophysiological parameters of the cerebral cortex and processes associated with arthrogryposis pathology. However, neurodynamical parameters in children with arthrogryposis are similar to those in healthy children. The results allow to state that arthrogryposis is reflected through decreased electrical activity of the cerebral cortex in 4–16 Hz range with preservation of neurodynamic characteristics typical for disease-free children. Conclusion. In this study, a significant difference in EEG power in 4–8, 8–12, and 12–16 Hz ranges between children with arthrogryposis and healthy children was demonstrated. However, there was no difference in such an important neurodynamical characteristic as long- range temporal correlations. It is possible that decreased amplitude of EEG rhythms in children with arthrogryposis is caused by their lower motor activity in general