Trunk rotation alters postural sway but not gait in female children and early adolescents: Results from a school-based screening for scoliosis

The purpose of this study was to assess the influence of trunk rotation (TR) on postural sway and spatial-temporal parameters of gait in children and early adolescents screened at school for the presence of scoliosis.Two hundred and fifty-five individuals aged 9-14 (141 boys, 114 girls) underwent trunk rotation (TR) assessment by means of angle of trunk rotation (ATR) measurements performed with Bunnell's scoliometer. Participants with ATR ≥ 5° formed the TR group whose data were compared with those of a control group (CON) composed of individuals with ATR < 5° matched for age and anthropometric features. Postural sway was calculated on the basis of center of pressure (COP) time series acquired using a pressure plate. Spatial-temporal parameters of gait were derived from trunk accelerations collected by a single inertial sensor located in the low-back region.Sway area, sway path, COP velocities in medio-lateral (ML) and antero-posterior (AP) directions and COP displacements in ML direction were found significantly higher in girls with TR, while no differences between the TR and CON groups were detected in boys. Both boys and girls with TR exhibited gait patterns similar to those of their CON schoolmates.These findings suggest that even mild levels of TR may influence balance of female children and early adolescents screened for scoliosis, and thus early interventions including selective and task-oriented exercises appear advisable. In contrast, TR does not appear to influence gait, but further investigations are required to clarify whether different ATR cut-offs may reveal alterations of spatial-temporal parameters.