Kinematic and kinetic features of an unaffected limb during walking in children with spastic hemiplegia

Introduction The study of the functional characteristics of the unaffected side of the musculoskeletal system in patients with spastic hemiparesis contributes to the development of various aspects of medical rehabilitation.Objective To determine the features of compensatory and adaptive behavior of the limb not involved in the pathogenesis in children with hemiplegia during walking and their dependence on age and previous surgical interventions on the triceps surae.Materials and methods Locomotor characteristics of 78 children under 16 years of age with spastic hemiplegia and motor disorders corresponding to levels I-II GMFCS (Gross Motor Function Classification System) were compared with 77 healthy peers. Based on age and the triceps surae lengthening surgery, all children were divided into 6 groups. Kinematic data were recorded using Qualisys 7+ optical cameras and KISTLER dynamometric platforms. The video material was analyzed using QTM and Visual3D programs, and statistical data processing was performed using Microsoft EXСEL-2013 and AtteStat 12.0.5.Results In the unaffected limb of children with spastic hemiplegia, a flexion position in the limb joints was observed, while the kinematics of its ankle joint did not differ significantly compared to healthy peers. Moreover, movements in the joints of the unaffected limb in children with hemiplegia were performed at greater energy consumption, especially in the knee and hip joints, while the power characteristics in the ankle joints were statistically lower than in healthy peers.Discussion Significant increase, in comparison with the norm, and redistribution of power locomotor characteristics, as well as an increase in the GPS indicator of the total joint kinematic variability of the limb not involved in the pathogenesis indicate exclusively the compensatory nature of its behavior. Compensatory behavior is also shown by increased flexion angles in the joints and the sagittal tilt of the pelvis, which posturally eliminate the difference in leg length. Rotational positions of the pelvis and the femur, apparently, also serve to maintain the orientation of the foot.Conclusion Compensatory behavior of the unaffected limb in children with hemiplegia during walking is manifested in kinetic and kinematic activity. Power locomotor characteristics are significantly redistributed compared to the normal values. Power indicators in the knee and hip joints increase, but power characteristics in the ankle significantly decrease. According to the GPS index, the total joint kinematic variability significantly increases, and the joint flexion angles and sagittal pelvic tilt increase to compensate for the difference in leg height. The procedure of early surgical lengthening of the triceps surae did not have a significant effect on the motor characteristics of the uninvolved limb.