Perception of vertical and horizontal orientation in children with scoliosis.

To determine whether the perception of body posture is altered in idiopathic scoliosis, a simple neurophysiologic experiment through laser line projection was conducted to test this hypothesis in three groups of individuals: 89 children with idiopathic scoliosis (IS), 50 children with congenital scoliosis (CS) and 45 controls without scoliosis. The subjects were instructed to adjust a laser line projection to the direction of gravity in vertical and in horizontal projections in a dark environment. The performance, expressed as the deviation from the earth vertical (measured in degrees), was calculated by a computer. The three groups fulfilled the vertical and horizontal adjustments within the same accuracy. No relation with age, sex or severity of scoliotic deformity was found. Yet, the angle between vertical and horizontal laser lines was significantly related with the severity of scoliosis, both in IS and CS. In contrast to our hypothesis, it was concluded that perception of postural control in IS is not altered. Therefore, this study indicates that IS is not likely to be caused by a dysfunction of postural control.