麻豆传媒

A cautious approach to releasing adolescents from braces to correct scoliosis didn't help keep the back straight better than going cold turkey once the brace had done its job, a randomized trial showed.

Immediate brace removal as soon as patients were eligible yielded similar change in major Cobb angle compared with an additional 6 months of nighttime wear before completely stopping, Jason Pui Yin Cheung, MBBS, MD, of the University of Hong Kong, and colleagues reported in .

That was true at 6 months post-weaning (difference -0.6°, P=0.17) and at 12 and 24 months (-0.3° for both, P=0.47 and P=0.60, respectively).

Given similar maintenance of brace outcomes with all differences well within the 5° measurement error range, the researchers wrote: "We recommend the more frequent use of immediate weaning protocol with appropriate patient selection, as patients with immediate weaning can return to increased exercises and activity level at an earlier time."

"It is important to avoid prolonged bracing as brace wear is potentially associated with flatback, muscle weakness, and reduced HRQoL [health-related quality of life] with time," they added.

What did make a difference was how much curvature and how much growth potential remained when the brace was removed. In both groups, those who progressed had larger mean major Cobb angles at weaning than those who didn't progress (35.7° vs 29.8° in the immediate group, P=0.002, and 33.5° vs 28.5° in the gradual group, P=0.006). Curve progression was independently predicted by radius grades, ulnar grades, Sanders stages, and Risser stages when brace use stopped (P<0.001 for all).

"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 DRU [distal radius and ulna] classification," Cheung's group wrote.

Their open-label trial included 369 adolescent idiopathic scoliosis patients (mean age 15 years, 83.4% female) at a territory-wide tertiary scoliosis clinic. The researchers recruited consecutive patients with good brace-wear adherence beforehand who were ready to wean off use of custom molded thoracolumbosacral orthosis and had reached skeletal maturity. The trial randomized 176 adolescents to the gradual weaning protocol -- with an additional 6 months of nighttime wear before completely stopping -- and 193 to the immediate weaning protocol at randomization. Outcome assessment was done by individuals masked to weaning protocol assigned.

Among the 284 (77.0%) patients who completed 24-month longitudinal follow-up, the gradual and immediate weaning groups had a comparable incidence of curve progression (19.0% overall, 29 vs 24 cases) and rebound (10.6%, 11 vs 19) as well as similar changes in truncal balance and health-related quality of life scores.

The results were similar for intent-to-treat and per-protocol analyses. Concordant results were seen at all three post-weaning time points as well.

"Gradual weaning may help minimize muscle discomfort from sudden straining without the brace, whereas immediate weaning is thought to lead to more back pain," the researchers noted. "Yet, both weaning protocols demonstrated comparable HRQoL, including not only overall but specific aspects, like pain, as captured by the SRS-22r [refined Scoliosis Research Society 22-item questionnaire total score] pain domain and EQ-5D [EuroQol 5-dimension] pain/discomfort dimension."

Any post-weaning intergroup difference was likely within the clinically relevant, minimum detectable measurement difference and also within the minimum clinically important difference, they added.

Limitations of the trial included lack of data on post-weaning exercise and activity levels and that there was no immediate assessment of muscle pain and paraspinal muscle adjustment at the 1- to 2-week point after weaning.

"We therefore cannot conclude on any difference of muscle pain level between weaning protocols though no difference of HRQoL was reflected at 6-month follow-up," Cheung and colleagues wrote. "In addition, the discrepancy of group sample size is suboptimal, and it could have been avoided."

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