Design is a prospective study including all IS patients with 45° or more, Risser 0-4, who had their first evaluation in our Institute from March 1st, 2003 to December 21st, 2010, and utterly deny any surgical intervention. Population: out of 59 patients, we excluded 2 still in treatment. 57 (11 males) were included, who at start of treatment had a mean of: 15.03±1.10 years of age, 52.5° Cobb (range 45-93°), and Risser 2 (0-4). Thirty-nine accepted a full-time brace treatment (BG) to try avoiding surgery, 18 served as controls (CG). Outcomes: radiographic and clinical data. Statistics: efficacy analysis in patients who completed treatment (38 in BG; 10 in CG; failures: surgery, progression 6° or more); intent-to-treat (failures also drop-outs). In CG, we had 8 patients not retrievable: they were considered as positive results (no progression or surgery) in the intent-to-treat analysis.