Reviewed for medical accuracy by Dr Evelyne Jonniaux, Medical Advisor
Last updated 17 September 2026
Bracing keeps 72 percent of adolescents below the surgical threshold against 48 percent without a brace, and three need to be treated to prevent one progression. But the wear actually measured in the trial was 12.1 hours a day against 18 prescribed, and the quartile wearing under 6 hours did no better than plain observation.
The questions we get asked
How many adolescents are concerned?
A meta-analysis of 34 studies and 2.8 million children screened at school gives 0.66 percent above 10 degrees, 0.33 percent above 20 degrees, and 0.02 percent above 40 degrees. The “2 to 3 percent” figure in circulation comes from a narrative review, not from primary data.
Does bracing work?
Yes, and the trial that showed it was stopped early for efficacy. In BrAIST, success, defined as reaching skeletal maturity without exceeding 50 degrees, was 72 percent with a brace against 48 percent under observation in the combined analysis, and 75 against 42 percent in the intention-to-treat analysis. The number needed to treat to prevent one progression warranting surgery is 3.0.
How many hours does it have to be worn?
This is the most useful part of the trial, because a thermal sensor measured actual rather than reported wear. Mean wear was 12.1 hours a day against a prescription of 18. Below 6 hours a day, the success rate is 41 to 42 percent, which is the result of observation alone. Above 12.9 hours it rises to 90 to 93 percent. An independent study showed that prescribing 16 or 23 hours produces exactly the same actual wear.
The claim that “bracing avoids surgery in 90 percent of cases” comes from that most adherent subgroup. It is not a randomised result and it does not describe what an adolescent gets on average.
What becomes of an untreated adolescent scoliosis?
A cohort followed for 50 years compared 117 untreated patients with 62 controls. Estimated survival probability 0.55 against 0.57 expected in the general population. Chronic back pain in 61 percent against 35 percent, but mild or moderate in more than two thirds of those affected. The authors conclude that these adults are productive and functional at a high level.
Respiratory failure appears only beyond extreme thresholds: vital capacity below 45 percent of predicted and a curve above 110 degrees. The documented excess mortality concerns infantile, juvenile and post-polio forms, not the adolescent form.
Is school screening worth it?
The US task force issued an insufficient-evidence statement in 2018: no study has measured the effect of screening on health outcomes. With a single test modality, more than four out of five children referred are false positives. Combining the forward bend test, a scoliometer and Moire topography raises the positive predictive value to 81 percent.
What the figures say
| Finding | Figure | Source |
|---|---|---|
| Adolescents with a curve above 20 degrees | 0.33 percent | Lam et al., Spine, 2026 |
| Bracing success against observation | 72 against 48 percent | BrAIST, N Engl J Med, 2013 |
| Number needed to treat | 3.0 | BrAIST, 2013 |
| Actual against prescribed brace wear | 12.1 hours against 18 | BrAIST, thermal sensor |
| Revision after fusion, at 5 years | 13.0 percent | Joo et al., Spine Deform, 2022 |
| Reported complications in paediatric spine surgery | 2.86 percent | Scoliosis Research Society registry, 2013 to 2020 |
One figure we could not source: the revision rate at 10 or 20 years with contemporary pedicle screw instrumentation. The 42 percent sometimes quoted comes from series operated with Harrington rods, a technique that has been abandoned.
What Noria Health does, and does not do
We organise a paediatric orthopaedic and spine consultation with a specialist team near Brussels, including review of existing radiographs and measurement of the curve. Feasibility is confirmed within 24 to 48 hours, follow-up documented at D14, D30 and D90.
We do not measure a Cobb angle remotely, we do not set an indication for bracing or surgery, and we never recommend interrupting orthopaedic treatment in progress.
Who reviewed this page
Noria Health editorial team.
See also: all our articles on paediatrics.
Have your case reviewed. Noria Health arranges a specialist consultation near Brussels and confirms feasibility within 24 to 48 hours. Open a case.