The effect of sublaminar wires on the rib hump deformity during scoliosis correction manoeuvres.

The sublaminar wire tightening towards the concave rod seemed to create an effect opposite of the desired effect, increasing the apical rotation and the thoracic rib hump deformity. Convexity manoeuvres (apical screw derotation and compression) are necessary and must be coupled with an under-bending of the convex rod to neutralise this effect.