Brace Dose in Scoliosis: Measurement, Monitoring, and Clinical Decision-Making—A Narrative Review

Introduction

Adolescent idiopathic scoliosis (AIS) is prevalent during growth and affects musculoskeletal health, psychosocial wellbeing, and long-term function.^1–3 It is also the most common form of scoliosis in adolescence, and although only a proportion of curves progress to a magnitude requiring active treatment, progression during skeletal immaturity remains clinically important because it can increase future deformity burden and the likelihood of more invasive treatment.^4,5 It is associated with back pain, activity limitation, and treatment-related distress,^3,6,7 and it drives repeated imaging, with some patients progressing to surgery.² For skeletally immature patients at risk of progression, bracing is a cornerstone strategy; outcomes depend on patient selection and high-quality implementation within structured, guideline-concordant pathways.^8,9 Landmark prospective evidence has shown that bracing can reduce progression to the surgical threshold in high-risk adolescents, reinforcing its central role in conservative management when applied to appropriate patients.¹⁰

Benefit is often diluted by suboptimal adherence.^9,11,12 Because brace treatment must be incorporated into school, sleep, body image, physical comfort, and daily routines, the amount of treatment actually delivered may differ substantially from the amount prescribed.¹³ Wear is challenged by discomfort/heat and body-image or school pressures, with negative psychosocial quality-of-life (QoL) effects.^6,7 Self-report can overestimate true wear, widening the efficacy-effectiveness gap.^12,14 This discrepancy also makes it more difficult to distinguish undertreatment from true treatment failure in both clinical practice and research.¹³ Compliance-support interventions (counseling and feedback informed by monitoring) may help, but effects are heterogeneous and implementation inconsistent.¹⁵

We therefore frame bracing as dose-dependent therapy in which delivered dose drives benefit, supported by dose–response evidence including wear above 18 h/day.¹¹ This dose-based perspective is also supported by comparative effectiveness evidence showing that time in brace is an important determinant of treatment success.¹³ Objective monitoring (thermal loggers) quantifies wear time and patterns and is linked to radiographic response.^12,14,16 Personalization tools (computer-aided design/computer-aided manufacturing [CAD/CAM]), finite element modeling (FEM) workflows and prognostic indices (eg., supine correction index) may refine correction, but still require dose measurement.^17,18 This narrative review synthesizes post-2015 evidence to present a dose-based framework and highlight gaps, including early adherence trajectories, variability between prescribed and achieved wear, and standardized reporting of delivered dose.

Previous reviews have addressed important but largely separate aspects of scoliosis bracing, including overall brace effectiveness, brace-related quality of life, adherence-enhancing interventions, CAD/CAM- or FEM-related brace design, and nighttime bracing.^7,15,19–22 However, these topics have rarely been integrated within a single clinically oriented synthesis centered on delivered brace dose. The aim of the present narrative review was therefore to synthesize post-2015 evidence on objective dose measurement, correction-related indicators, personalization strategies, wear schedules, EOS/juvenile considerations, and patient-centred outcomes within one framework for measurement, monitoring, and clinical decision-making.

Material and Methods

This narrative review was designed to examine scoliosis bracing as a dose-dependent therapy, with a particular focus on objectively measured adherence (“delivered dose”) and its implications for clinical monitoring and decision-making. We used the Scale for the Assessment of Narrative Review Articles (SANRA) to guide rigor in defining the rationale, scope, transparency, referencing, and clinical interpretability of the review,²³ and we described key search and selection elements to improve methodological clarity without conducting or claiming a systematic review.²⁴

To identify contemporary evidence most relevant to current brace monitoring technologies, personalization strategies, and clinical decision-making, we performed a structured search of MEDLINE (PubMed), Scopus, Web of Science Core Collection, and, when accessible, Embase for studies published from 1 Jan 2015 to 30 Jan 2026. This time window was selected to focus the main synthesis on contemporary literature reflecting current brace-monitoring technologies, newer personalization workflows, and recent comparative outcome data that are most applicable to present-day clinical decision-making. Earlier foundational studies remain relevant to the field and were cited selectively outside the primary search window when needed to provide essential clinical context and support key background concepts. Search terms combined scoliosis populations, bracing/orthoses, adherence and dose monitoring, in-brace correction, computer-aided design/computer-aided manufacturing (CAD/CAM), finite element modeling (FEM), and three-dimensional (3D) printing. Records identified through this search were reviewed for relevance on the basis of title, abstract, and, where needed, full-text assessment.

We prioritized peer-reviewed human studies on brace treatment, mainly in adolescent idiopathic scoliosis (AIS). Selected juvenile and idiopathic early-onset scoliosis (EOS) studies were included only when directly relevant to the review question and were interpreted cautiously given differences in age, growth potential, treatment duration, and overall evidence base. Because the aim of this review was thematic and clinically interpretive rather than exhaustive or meta-analytic, formal duplicate screening, protocol registration, and PRISMA-style study accounting were not undertaken. Older seminal studies were therefore not treated as ineligible; rather, they were cited selectively outside the main search window when needed to provide essential clinical context, foundational evidence, or historical support for concepts that continue to inform contemporary brace research and practice.

The included literature was synthesized narratively across five predefined domains: objective adherence monitoring, CAD/CAM/FEM-related personalization strategies, nighttime versus full-time protocols, early-onset/juvenile scoliosis, and patient-reported outcomes (PROs). Methodological appraisal was performed informally to guide interpretation of the literature rather than to generate formal study-level ratings or determine inclusion. These considerations were applied during full-text interpretation and thematic weighting of the included literature, rather than as formal eligibility or exclusion criteria. In this appraisal, greater interpretive weight was given to study design, sample size, measurement validity, follow-up adequacy, and likely sources of bias or confounding. Key post-2015 evidence across these five domains is summarized inSupplementary Table S1.

Defining “Brace Dose” and Why This Definition Matters

Conceptual Premise

Bracing is best understood as a dose–response therapy in which outcomes depend on the delivered magnitude and consistency of corrective exposure, not the prescription alone. The International Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT) guidance highlights both compliance and initial in-brace correction as key drivers of success, implying that “brace dose” must capture wear and correction quality together.⁸ We conceptualize brace dose as a multidimensional construct spanning quantity (measured wear time), pattern (regularity), and correction/force quality; key components and minimum reporting indices are summarized in Table 1.

Table 1 Conceptual Components of Brace “Dose”, Their Measurement, Suggested Reporting Indices, and Key Limitations

Components of Dose

A clinically useful way to conceptualize brace dose in AIS is as a multidimensional construct. Quantity (objective hours) is foundational because temperature-log studies show persistent gaps between prescribed and achieved wear and systematic overestimation with self-report.¹² Pattern (regularity) also matters: more consistent daily wear has been linked to better short-term results.²⁵ Correction intensity/quality can be pragmatically approximated by in-brace correction (IBC), but IBC should be interpreted as an early surrogate of the brace’s immediate corrective effect rather than a direct measure of wearing quality alone. IBC is influenced by several factors, including curve flexibility, brace design, pad placement, and fitting. 3D analyses show braces differ across coronal, sagittal, and transverse effects, and evidence syntheses identify IBC among the most consistent predictors of outcome.^26,27 Prognostic context can be refined using baseline-adjusted indices such as the supine correction index and related measures.^18,28 Finally, effective dose requires mechanical transmission; force/pressure and real-time monitoring systems can quantify brace–torso interaction and show that delivered forces may drift, potentially decoupling “hours worn” from “hours effectively corrected.”^29–31 Patient-specific modeling supports a mechanobiologic rationale for including loading patterns in the delivered dose construct.³² Taken together, these components are best interpreted as a conceptual framework for describing delivered dose rather than as a single validated metric with fixed clinical thresholds.

Conceptual working model: Delivered brace dose can be understood as a function of objective wear time together with correction intensity/quality, interpreted in the context of wear pattern and fit stability.

Prescribed versus Received Dose

Achieved wear time varies widely and is often overestimated without objective monitoring.¹² Early adherence predicts future wear behavior and is associated with later outcomes, supporting longitudinal “dose trajectory” assessment.³³ Comparative effectiveness analyses indicate that higher hours/day can explain between-cohort failure differences.¹³ Dose–response evidence extends above ~18 h/day for selected endpoints.¹¹ Determinants studies further show that geography, patient factors, and prescription features influence achieved wear time, reinforcing measurement over assumption.^34,35

Implications

Studies should report objective wear distributions/trajectories and include at least one correction-related indicator (eg, IBC and/or force measures) to reduce exposure misclassification, while recognizing that no single measure currently captures delivered dose in full Analyses should separate prescription effects from delivered dose, since monitoring and adherence-support interventions may increase wear time, though effects are heterogeneous.^15,36 Clinically, a treat-to-target approach uses objective monitoring plus early radiographic checks; early out-of-brace radiographs may improve prediction beyond in-brace films alone.³⁷

Objective Monitoring of Adherence: From Sensor Readout to Clinical Decision-Making

Objective monitoring converts brace adherence from self-report to a measurable exposure, enabling dose-based bracing. Temperature loggers with threshold algorithms classify “worn” time and reveal variability that self-report misses.¹² This can make counseling data-driven by highlighting gaps and trends.³⁸ Thermal systems are feasible in routine care, but validity depends on sensor position and temperature thresholds; these choices affect misclassification.³⁹ Because “time worn” cannot confirm “how well worn,” force/pressure sensing and hybrid force+temperature platforms aim to capture both quantity and a tightness/force surrogate, supporting iterative adjustment.^40–42 Connected systems may shorten feedback loops and enable targeted interventions (eg., schedule redesign, refitting).³¹

Monitoring can also modify behavior: families report good acceptability, and consistent daily wear patterns have been linked to better outcomes.^14,25 Evidence syntheses suggest sensor monitoring, often paired with education/feedback, can increase objectively measured wear time, although effects are heterogeneous and certainty is limited.^15,36 In minors, monitoring requires clear assent/consent, data minimization, and secure governance; digital-health ethics and analyses of wearable privacy policies highlight fiduciary-like duties and transparency gaps, supporting clinic-level oversight.^43–45

Objective adherence data reframe “brace efficacy” by separating failure from undertreatment and reducing exposure misclassification.¹² Cohort and comparative-effectiveness data support a relationship between time in brace and outcomes, and secondary analyses suggest that for some selected endpoints the benefit may extend above 18 h/day; however, these findings should not be interpreted as a uniform threshold across all clinical outcomes.^11,13,35 Early adherence predicts future wear, and sensor-derived dosing informs nighttime protocols and correlates with radiographic outcomes in routine care.^16,33,46

Evidence for a Dose–Response Relationship and Key Effect Modifiers (AIS vs EOS/Juvenile)

Bracing remains the cornerstone non-operative strategy for growth modulation in moderate AIS, outperforming observation for preventing clinically meaningful progression (commonly ≥5–6°) and reducing progression to surgical magnitude in skeletally immature patients.^9,47,48 Contemporary evidence supports dose dependence, particularly for objectively measured time in brace: in the Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) vs the Italian Scientific Spine Institute (ISICO) comparative effectiveness analyses, objectively measured time in brace explained differences in failure rates, and each additional hour/day reduced failure odds after adjustment for baseline factors.¹³ Extending beyond the traditional ≤18 h/day framing, a secondary analysis of patients prescribed >18 h/day showed higher objective wear quartiles associated with better performance on stricter endpoints, particularly end-of-growth Cobb <30° and radiographic improvement, while some “avoid surgery” endpoints showed ceiling effects. These findings suggest that the optimal dose may be endpoint-specific rather than defined by a single universal cut-off.¹¹ Wear effects are further conditioned by correction quality and maturity: both brace wear time and in-brace correction predicted avoiding surgical conversion, with skeletal maturity modifying the association.⁴⁹

Dose–response does not occur in isolation. Prognostic syntheses highlight skeletal maturity, initial Cobb magnitude, curve pattern, and early radiographic response as consistent predictors, despite heterogeneous definitions across studies.²⁷ Larger curves remain higher risk even with measured adherence, and thoracic curves may progress more than lumbar curves despite similar wear time, implying curve-type specific dose requirements.⁵⁰ Early out-of-brace radiographs may predict end results better than in-brace films, emphasizing durable correction.³⁷ Achieved dose is also shaped by personal/contextual determinants and real-world care pathways, reinforcing the need to measure delivered dose.⁵¹

Most dose–response and delivered-dose data are AIS-based and should not be assumed to translate directly to juvenile or idiopathic EOS populations. In idiopathic EOS, evidence to skeletal maturity is low quality, with a pooled surgery rate of about 40%, and progression risk linked to larger initial Cobb angles, younger age at bracing, smaller in-brace correction, and poor compliance.⁵² Juvenile-onset cohorts suggest that bracing can delay or avoid surgery in some patients, but outcomes remain highly dependent on baseline curve severity, curve pattern, and the prolonged treatment course, with substantial between-study variability.^53,54 Accordingly, juvenile and idiopathic EOS findings are better interpreted as related but distinct evidence streams rather than direct extensions of AIS-based dose–response data.

Next-Generation Braces for Increasing the “Effective Dose”

Next-generation bracing aims to increase effective dose by improving correction per hour, tolerability, and the speed of iterative adjustment using objective feedback, but the extent of these advantages remains dependent on device type, workflow, and the maturity of the supporting evidence.⁸ CAD/CAM improves reproducibility, while FEM-enabled CAD/CAM is intended to optimize biomechanical features such as pad placement, stiffness, and relief to improve 3D correction with less coverage; RCTs suggest improved immediate in-brace and/or 3D correction with FEM-informed designs in selected settings.^55,56 However, a 2-year RCT with objective adherence monitoring and the Scoliosis Research Society–22 revised questionnaire (SRS-22r) found both CAD/CAM approaches effective without clear differences in correction, adherence, or QoL, implying that digital refinement matters only if it meaningfully changes received hours and/or correction-per-hour.¹⁷ Reviews similarly conclude CAD/CAM outcomes are at least comparable to conventional fabrication, with FEM’s incremental advantage context-dependent.^19,57 Current trends include simulation from one radiograph plus surface topography, improved predictive brace-action models, growth-modulation FEM incorporating compliance, and automated optimization; optimized nighttime designs are advancing through crossover RCTs and prospective protocols.^32,58–61

3D printing enables lightweight, ventilated, locally tuned stiffness shells; feasibility and perforation-optimization studies support technical viability.^62,63 Clinical evidence remains early but includes an RCT with objective wear monitoring, prospective protocols, and patient-specific series.^64–66 Overall, “more hours” alone may be insufficient; current evidence supports considering integrated pathways that combine objective correction assessment, objective wear tracking, PROs, and redesign loops, although this remains a pragmatic interpretation rather than a fully validated care standard.

Brace Selection and Wear Schedule (Full-Time vs Night-Time)

Rigid bracing is the main nonoperative strategy in AIS; guidance positions full-time bracing as the default for meaningful progression risk.⁸ Because prescribed hours do not equal delivered dose, schedule (full-time vs night-time) must be considered with adherence, in-brace correction, and acceptability.⁶⁷ Post-2015 syntheses suggest night-time can be effective in selected patients (thoracolumbar/lumbar, Risser 1–2), but pooled progression is substantial and evidence heterogeneous; reviews caution against universal night-time.²⁰ Comparative cohorts conflict: a multicenter main-thoracic study found similar progression for Boston full-time and Providence night-time,⁶⁸ whereas a 358-patient cohort favored Boston full-time, especially in pre-menarchal patients, thoracic curves, and Cobb >30°.⁶⁹ RCT data indicate comparable 2-year curve control, but early self-image/pain may favor night-time, and the CONservative TReatment for Adolescent Idiopathic Scoliosis (CONTRAIS) trial supports night-time over physical activity alone in moderate AIS declining full-time.⁷⁰ Objective monitoring shows early weeks are pivotal and early adherence predicts future wear.^33,71 Sagittal profile may differ (underarm full-time linked to flatback; Providence night-time shows no hypokyphosis).^72,73 A pragmatic interpretation of the available evidence is to risk-stratify by maturity, Cobb angle, and curve type; generally favor full-time bracing for higher-risk presentations; consider night-time protocols in selected moderate-risk cases or when full-time wear is not feasible; and reassess at 6–12 weeks using objective wear data and radiographic correction before considering escalation.²¹

Patient-Centred Outcomes & Adherence-Enhancement Strategies

PROs are essential in brace-treated AIS because “success” includes functioning, psychosocial well-being, and tolerability, not only radiographic stability. Self-image/body configuration and psychological stress are the most consistently affected domains.⁷ Studies using brace-specific (Brace Questionnaire [BrQ]) and generic instruments (SRS-22r, EuroQol 5-Dimension [EQ-5D]) show heterogeneous trajectories, with a subset experiencing meaningful impairment in psychological, social, and school-related domains, often with pain and activity restriction.^6,74 Body image and QoL are closely related, yet psychosocial distress does not map linearly to objectively measured wear, so counseling should avoid simplistic assumptions.⁷⁵ Regimen can modify PROs: a randomized trial found similar curve control for full-time versus night-time bracing, but time-specific self-image and pain signals favored night-time protocols.⁷⁶ Qualitative evidence highlights school-time challenges (visibility, stigma, discomfort, heat, logistics) and a dynamic adherence process where early disruption can lead to selective wear, while supportive communication and accommodations facilitate re-engagement.^77,78

Implementable adherence support aligns with SOSORT guidance and interprofessional models.^8,79 Core elements include dose literacy and expectation-setting, co-design and comfort optimization, and objective monitoring with non-punitive feedback; syntheses suggest monitoring and multimodal interventions can increase wear time, though effects are heterogeneous, and acceptability is generally high with appropriate consent and governance.^14,15,36 Targeted psychosocial support is feasible and may improve coping and brace use; mindfulness-based intervention showed benefit signals in poorly adherent patients.^80,81 A practical clinic bundle combines baseline PROs, early fit checks, sensor-guided feedback, and escalation when distress threatens dose delivery.

Message for Clinical Practice: “Precision Bracing” as a Pragmatic Clinical Framework

Precision bracing can be viewed as a dose-dependent approach in which clinical benefit is more closely linked to delivered (measured) dose than to prescription alone; in this review, the term is used as a pragmatic clinical framework derived from the available evidence and expert synthesis rather than as a validated guideline.^8,82 This pragmatic framework is illustrated in Figure 1.

Figure 1 Practical “precision bracing” framework integrating risk stratification, brace selection, explicit dose targets, objective dose monitoring, early reassessment, and escalation actions based on delivered dose and clinical/PRO response.

In practical terms, this framework may be applied by first risk-stratifying the patient (maturity, Cobb angle, curve pattern), noting that EOS/juvenile evidence is more heterogeneous and long-term failure risk is higher than AIS; then choose brace type and schedule to maximize effective dose while balancing biomechanics and feasibility, with CAD/CAM ± FEM as potentially useful options to refine correction and tolerability where available, while recognizing that their incremental clinical advantage remains context-dependent.^17,52,56 Set explicit dose targets linked to endpoints, recognizing that evidence for benefits beyond 18 h/day is currently limited to selected outcomes and should not be generalized uniformly across all patients or endpoints.¹¹ Measure adherence objectively (thermal sensors) and use data for supportive feedback, given acceptability and evidence for adherence-enhancing interventions.^12,14,15 Re-titrate by optimizing fit/correction and considering early out-of-brace radiographs for prognosis rather than simply prescribing more hours.^37,73 Minimum reporting should include indication/maturity, baseline curve descriptors, brace type and prescribed dose, objective adherence methods with distributions/regularity, radiographic protocols, standardized clinical outcomes, and patient-centred outcomes.^8,37,82 Figure 2 illustrates the conceptual model linking patient factors, brace strategy, delivered dose, and outcomes, together with the iterative feedback loop for reassessment and care adjustment.

Figure 2 Conceptual “Precision Bracing” model linking inputs (patient factors, curve phenotype, and brace strategy) to radiographic and patient-reported outcomes through objectively measured delivered dose, with an iterative feedback loop for dose optimization actions (refit/redesign and adherence support).

Discussion

Current evidence most consistently supports several points. Brace research is limited by inconsistent reporting of delivered “dose,” despite SOSORT–SRS recommendations.⁸² Objective monitoring shows that received dose often differs from prescriptions, so dose should be measured as an exposure rather than assumed. A minimum dataset should report schedule; objective adherence methods (sensor type/placement/algorithm) with distributions and patterns; brace type/fabrication; and correction-quality metrics, including early out-of-brace radiographs.^12,37 Dose–response signals beyond 18 h/day for selected endpoints, together with prognostic early adherence data, support consideration of early checkpoints and adaptive titration; however, the evidence base remains heterogeneous and does not yet define universal dose thresholds or standardized optimization protocols.^11,33

Beyond these evidence-supported findings, this review offers an interpretive synthesis in which brace treatment is viewed as a dose-dependent intervention and “precision bracing” is framed as a pragmatic, evidence-informed clinical approach. Accordingly, some practice implications in this review should be interpreted as evidence-informed pragmatic inferences rather than as uniformly validated recommendations. The proposed precision-bracing framework should therefore be understood as a conceptual and pragmatic tool to support clinical judgment, rather than as a formal guideline or validated management algorithm.

Several methodological and research priorities follow from this synthesis. Because compliance-enhancing interventions are heterogeneous, pragmatic and registry-embedded studies with objective adherence and standardized outcomes are needed.^15,36 Methods should be reported using the CONSORT extension for trials conducted using cohorts and routinely collected data (CONSORT-ROUTINE) and the REporting of studies Conducted using Observational Routinely collected Data (RECORD) guideline, with EOS/juvenile scoliosis prioritized. Patient-centred outcomes should be core outcomes; a bracing-specific core outcome set (COS) developed and reported using Core Outcome Set–STAndards for Development (COS-STAD) and Core Outcome Set–STAndards for Reporting (COS-STAR), alongside Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020-aligned reviews, would improve comparability.^83–86

This SANRA-guided narrative synthesis is not exhaustive and does not pool estimates.²³ The literature varies in brace concepts, dosing targets, imaging protocols, and outcome definitions, limiting comparability.⁸² Adherence assessment differs (objective sensors vs self-report), potentially biasing delivered-dose estimates and dose–response inference.^12,15,36 Effective dose is not hours/day alone; unmeasured correction quality, fit/force, and wear regularity may confound associations, even where higher-dose effects are observed.^8,11 PROs are inconsistently captured, and the absence of an agreed COS limits synthesis of patient-centred benefit and burden.^83,84 These limitations reinforce standardized reporting and pragmatic designs reported with CONSORT-ROUTINE.^82,87

Conclusion

Bracing is best conceptualized as a dose-dependent therapy in which clinical benefit depends on the delivered, not merely prescribed, dose. Current evidence most consistently supports the value of objective adherence monitoring, early adherence and correction-related assessment, and the importance of distinguishing undertreatment from true treatment failure. On this basis, precision bracing may be viewed as a pragmatic, evidence-informed clinical framework for linking objective dose measurement to individualized reassessment and care adjustment. However, the available literature remains heterogeneous, and many practice implications should still be interpreted cautiously rather than as universally validated rules. Future progress will depend on more standardized reporting of delivered dose and more consistent inclusion of patient-centred outcomes alongside radiographic endpoints.