Table 3.

Aims of treatments, over-, and under-treatment according to the different clinical situations.

Clinical Situation at the Start		Aims of Treatment According to Current Guidelines [11]		Thresholds of Over- and Under-Treatment
Degree of scoliosis	°Cobb	Primary aim	Minimal aim	Over-treatment	Under-treatment
Low	11–20	End of growth < 20°	End of growth < 45°	Improvement > 5°	End of growth > 30°
Moderate	21–25	End of growth < 30°		Improvement > $5{}^{°}+\left(\frac{{}^{°}\mathrm{Cobb}\mathrm{start}-20{}^{°}}{2}\right)$
	26–30				Progression > 5° #
	31–40
Severe	41–45	End of growth < 45°	End of growth < 60° *

Current guidelines [11] define the primary aim as the optimal desired achievement, while the minimal aim corresponds to the minimum desired achievement, in cases where it is impossible to obtain the primary aim. Keeping in mind the threshold of 30° [12,13,14], under-treatment has been defined when the deformity progressed above this significant threshold or, if already above, if it progressed at all. Conversely, over-treatment has been defined when there have been successful (1) improvements, for starting points below 21°; (2) important improvements according to a specific formula, reaching scoliosis below 30°, for starting points above 20°. * For severe curves, the guidelines propose postponing surgery [11]. We arbitrarily decided that a 60° curve requires immediate surgery, while below it is still possible to achieve results with conservative treatment [21] and set this threshold. # Only if therapy intensity was below 6.