Bracing outcomes in teens with scoliosis do not differ with immediate vs gradual weaning protocol

For teenagers with idiopathic scoliosis who wear a corrective brace, gradual removal of the device offers no significant advantage over immediate removal in terms of bracing outcomes and quality of life, according to the results of an open-label randomized clinical trial in Hong Kong.

In the intention-to-treat population, changes in the primary outcome of major Cobb angle between the immediate and gradual weaning protocols were similar at the postweaning follow-up of 6, 12, and 24 months, the investigators reported.

The adjusted mean change in major Cobb angle at 24 months following brace removal was 3.2° in the immediate weaning group vs 3.0° in the gradual weaning group, with a between-group difference of −0.2° (95 confidence interval [CI], −1.2 to 0.7; p=0.64). The corresponding between-group differences at the 12-month and 6-month postweaning follow-ups were −0.4° (95 percent CI, −1.3 to 0.5; p=0.44) and −0.6° (95 percent CI, −1.4 to 0.2; p=0.15). [JAMA Pediatr 2024;doi:10.1001/jamapediatrics.2024.1484]

“The magnitude of changes in Cobb angle from baseline for each weaning protocol was within the measurement error range of 5°, while the intergroup difference was within the equivalence margin of 2°,” the investigators noted. “The effect of weaning protocol on major Cobb angle changes at all time points was insignificant, with or without covariate adjustment.”

Compared with a gradual weaning protocol, immediate brace removal did not increase the number of curve progression and rebound cases (p=0.35). Neither immediate nor gradual weaning showed a clear advantage in terms of postweaning truncal balance and health-related quality of life (HRQoL).

“Gradual weaning may help minimize muscle discomfort from sudden straining without the brace, whereas immediate weaning is thought to lead to more back pain. Yet, both weaning protocols demonstrated comparable HRQoL, including not only overall but specific aspects, like pain, as captured by the pain domain score on the Scoliosis Research Society 22-item questionnaire and the pain/discomfort score on the EuroQol 5-dimension instrument,” the investigators pointed out.

In light of the findings, the investigators recommended the more frequent use of immediate brace weaning protocol with appropriate patient selection to allow patients to resume exercise and increase their activity level at an earlier time.

The study included 369 adolescent idiopathic scoliosis (AIS) patients (mean age 14.9 years, 83.4 percent girls) who were ready to wean off brace wear. These patients were randomly assigned to immediate (n=193) or gradual (n=176) weaning protocol. The gradual weaning protocol involved a 6-month period of nighttime-only brace wear, followed by complete removal. A total of 77.0 percent of patients completed the 24-month longitudinal follow-up.

Curve progression risk

“Brace weaning can be a slow process… Some clinicians err on the side of gradual weaning to be certain that curves remain stable after some months of reduced brace hours, whereas others prefer immediate weaning for earlier return to normality with complete resumption of exercises, muscle training, and activity level,” the investigators said.

When assessing the risk of progression after brace removal, clinicians must consider curve severity and remaining growth potential rather than the specific weaning process, they pointed out.

Indeed, patients who progressed in the study had significantly larger major Cobb angles at weaning compared with those who did not progress both in the immediate weaning (35.7° vs 29.8°, p=0.002) and gradual weaning (33.5° vs 28.5°, p=0.006) groups. Multivariable analyses showed that curve progression was associated with both Major Cobb angle (p<0.001) and skeletal maturity (radius grades: p=0.007; ulna grades: p=0.001; Sanders stages: p=0.006; Risser stages: p=0.47) at weaning.

“Current practice based on Risser staging can possibly be improved by new brace weaning protocol using other skeletal maturity indices such as Sanders staging and distal radius and ulna classification,” the investigators said.