Torso rotational component in movement patterns in healthy children

In order to assess the presence of the rotational component of the trunk in locomotor activity and determine its functional status in the horizontal plane, healthy children (n = 63) aged 12-18 years were examined. Biomechanical assessment of the locomotor profile was carried out using 3D video analysis under conditions of habitual gait. To analyze the biomechanical behavior of the elements of the musculoskeletal system, statistical criteria for variational identification for normal distribution were used. And the analysis itself was carried out according to the parame-ters characterizing the final adaptive result in sample populations specially selected with the maximum possible ontogenetic and morphofunctional homogeneity of the studied material. As a result of the study, it was established that: in phylo- and ontogenetically homogeneous sample populations, the parameters of arbitrarily induced locomotor activity characterizing the final adap-tive result approach the normal distribution function. The rotational component of the trunk in the form of in-phase and anti-phase coordinate orientation of its segments in the horizontal plane is not regulated arbitrarily, and in the usual locomotor activity is a postural quantitative characteris-tic of a systemically determined motor stereotype and a result of postural-locomotor self-organization of genetically programmed sensorimotor systems. The recorded systemically de-termined locomotor stereotypes with anti-phase and in-phase postural orientation of the trunk segments in the horizontal plane are implemented by two different sensorimotor systems and are launched, apparently, at the moment of registration by the current balancing value of sensorimo-tor synthesis. From the standpoint of the systems approach, the criteria for variational identifica-tion of the biomechanical behavior of the musculoskeletal system in onto- and phylogenetically homogeneous sample populations will allow, based on the parameters of the final adaptive re-sult, to study the functions of sensorimotor systems in their “pure form” without compensatory-adaptive participation from auxiliary uncontrolled sensorimotor resources.