Case report: 39° curve down to 12.5° after about 4 years of bracing

Scoliosis may be a single (C) curve or a double (S) curve. This case has one lumbar curve with its apex at L1 and a Cobb angle of 38.65°. The range 25°–40° is where bracing has the best evidence in a child who is still growing: the BrAIST trial (NEJM 2013) of 242 children with a Cobb angle of 20°–40° recorded 72% success in the braced group versus 48% with observation alone, and the 2016 SOSORT guidelines recommend bracing for growing children with a curve above about 20° and a risk of progression.

According to the clinic, the patient was 15 and at Risser 3 at the first visit, meaning the skeleton was partly ossified with a limited amount of growth remaining. Risser 3 is within SOSORT’s indication for bracing (Risser 0–3) but outside the range of the BrAIST trial (Risser 0–2), so BrAIST’s figures do not apply directly to this patient. The higher the Risser grade, the less growth remains and the lower the risk of progression usually is compared with Risser 0.

Two X-ray views and the back photo were taken at the same time. The left film is flipped to look as if seen from behind, the right film is seen from the front. The orange lines are the Cobb-angle measurement lines and the red boxes give each measurement. Result: 38.65°.

The back photo shows a shifted trunk and uneven waistlines, matching the lumbar curve on the film. Surface photos only illustrate; they do not replace X-rays.

On 28 August 2026 (the patient aged 19, after about 4 years of treatment) the clinic took the final film of the treatment. The day brace had been weaned about 6 months earlier and only the night brace remains; according to the clinic the night brace will be worn for a while longer, at least a year after the day brace was weaned, before being reduced gradually. With the day brace weaned there is no day-brace film to compare; the final film has only two conditions: out of brace and in the night brace.

Using the lower angle (the lumbar curve, the main curve used for comparison from start to end): out of brace the Cobb angle is 12.5° (curving to the left); in the night brace it is −5.5°, meaning the curve is pushed past straight and now bends to the opposite (right) side. The imaging report (which carries personal details) is not published; the article uses only its numbers.

Compared with the first-visit film (2 Aug 2022, 38.65°): out of brace the angle fell to 12.5°, about 68% lower (26.2°). According to the clinic the curve may relax slightly after the day brace is weaned, which is also why the night brace continues. 12.5° is still far below the surgical range, but as it is above 10° and the Cobb measurement error is about ±5°, it still needs follow-up.

The clinic’s protocol: wear the brace until skeletal maturity is complete and the curve no longer responds to corrective force, then about a year more to be safe; after that the day brace is weaned first, then the night brace is reduced gradually. At the final film the day brace had been weaned about 6 months earlier and the patient was at the night-brace stage (to continue for at least another year). Complete night-brace weaning and further follow-up are needed for a final conclusion on the criterion of avoiding surgery; at 12.5°, far below the 50° threshold, this case is currently very far from the surgical threshold.

We searched PubMed for the average in-brace correction. We found no formal meta-analysis giving one overall average: the systematic review of Peeters et al. (Spine 2022; 28 studies) only synthesised predictive factors (curve flexibility is strongly linked to in-brace correction; CAD/CAM and plaster-cast braces do not differ clearly in correction), and the meta-analysis of Zheng et al. (Children 2023) reports only differences in degrees. We therefore compiled individual studies.

Arithmetic: for the five full-time-brace groups with a reported mean (Emans, Lou, Brown and the two groups of Bonsignore-Opp; 474 patients in all), the sample-size-weighted mean is about 47%. Individual study means range from 22% to 55% for full-time braces, up to 73% for thoracolumbar curves and 96–98% for the Providence night brace measured on supine films (supine films usually give a higher correction than standing films). This is our own arithmetic, not a formal meta-analysis.

Interpretation: at the final film the night brace took the lower angle from 12.5° (out of brace) to −5.5°, i.e. past straight, more than the weighted mean of about 47% and the 73% for thoracolumbar curves in Davis’s study. Note that the night-brace film was taken lying down, and supine films usually show higher correction than standing films (the 96–98% for the Providence night brace was also measured on supine films); this is also only one patient. The main conclusion is therefore that this case’s night brace corrects very well at the time of the final film.

The final result, in the same unit (degrees of improvement): in the Boston study of Emans et al., at least a year after brace wear stopped, 49% of patients had a curve within ±5° of the start, 39% improved by 5°–15° and only 4% improved by more than 15°; the average out-of-brace correction was only about 23% at the start of weaning and 11% at the last follow-up. In Brown et al. the mean final major curve was 32 ± 12° (starting curves 20°–40°). This case improved by 26.2° (about 68%) out of the brace, which falls in the rare group in those studies. Note that the Boston study is old, covers many curve patterns, and the sample case is still wearing a night brace.

On accompanying outcomes: in D’Amato et al., the share with no progression beyond 5° was 93% for thoracolumbar and 94% for lumbar curves (all 102 children: 74%); in Brown et al., the group with correction of 45% or more had an 88% success rate. These rates use different criteria and cannot be compared directly with BrAIST’s rate of avoiding surgery.

Surface photos help parents see the change in trunk posture over time. The photos are kept as in the clinic’s original, including the notes written on the body.

Before comparing, three different kinds of number must be kept apart, because they measure different things and cannot be compared directly: (1) a trial success rate is the share of patients with a good outcome, e.g. in BrAIST a Cobb angle still below 50° at skeletal maturity (i.e. below the surgical threshold); (2) in-brace correction is the percentage by which the curve is reduced while wearing the brace; (3) the 68% of this case is the percentage reduction of one patient’s Cobb angle (38.65° → 12.5°).

These studies show associations at group level; they do not prove that those factors produced the result in this one patient. No study allows an exact success rate to be calculated for this case; an individual estimate can be made with the BrAIST-Calc tool (Dolan et al., Spine 2024), which needs age, sex, BMI, Risser stage, Cobb angle and average daily wear hours. For this case age (15), sex (female), Risser (3), Cobb angle (38.65°) and wear hours (about 22 hours/day) are known; only BMI is missing.