Fig. 5.

The efficiency of the “three-point system” depends on several factors, among them, the distance between the two proximal and distal points of the system. Curve pattern by itself is one of the factors determining a major or minor correction. Using here the simplest classification of single, double, or triple structural curve, the best correction might be achieved in the simple structural curve pattern and the worse in the triple structural curve pattern. Looking at the main thoracic curve, the distance between proximal and distal pads is higher in the first case (a) than in the last case (e). The very low distance between the two pads converts the proximal thoracic curve in the most difficult to correct (f) in the hypothetical case of locating all the pads underarm