Efficacy of nighttime brace in preventing progression of idiopathic scoliosis of less than 25°

Adolescent and Juvenile Idiopathic Scoliosis: Which Patients Obtain Good Results with 12 Hours of Cheneau–Toulouse–Munster Nighttime Bracing?

Background: The results of 12 h nighttime Cheneau–Toulouse–Munster (CTM) brace wear on adolescent idiopathic scoliosis are poorly described. Objective: The main objective was to analyze the efficiency of 12 h nighttime CTM brace wear on adolescent idiopathic scoliosis. The secondary objective was to identify the factors influencing good results. Methods: One hundred and fifty consecutive patients treated between 2006 and 2017 were retrospectively analyzed with subgroup analysis for the main curve pattern (main thoracic or main lumbar). The inclusion criteria were evolutive scoliosis, 12 h nighttime CTM brace wear, Risser stages 0-1-2 at the time of the prescription, and Cobb angle below 45 degrees. Success was defined as no surgery, and the main curve Cobb angle (CA) progression ≤5°. The overcurve was defined as the proximal thoracic curve above the main thoracic and mid-thoracic above the main lumbar curves. A logistic regression model was built to assess the predictors of success. RESULTS: Overall success was 70%: 60% for main thoracic (MT) and 84% for main lumbar scoliosis (ML) (p = 0.003). Efficacy was 62% at Risser stage 0 and 78% at Risser stage 1–2 (p = 0.054). For MT, failure was associated with high in-brace sagittal C7 tilt (Odds Ratio = 0.72, p = 0.014) and low initial overcurve CA (Odds Ratio = 0.42, p = 0.044). For ML, a high standing height was associated with success (OR = 1.42, p = 0.035), and frontal unbalanced C7 tilt was associated with failure (OR = 0.43, p = 0.02). Conclusion: Twelve-hour nighttime CTM brace wear provided good results for main lumbar curves with balanced frontal C7 tilt. For MT, this treatment is indicated if the in-brace sagittal C7 tilt is well balanced from Risser stage 2.

Application of deep learning upon spinal radiographs to predict progression in adolescent idiopathic scoliosis at first clinic visit

BACKGROUND

Prediction of curve progression risk in adolescent idiopathic scoliosis (AIS) remains elusive. Prior studies have revealed the potential for three-dimensional (3D) morphological parameters to prognosticate progression, but these require specialized biplanar imaging equipment and labor-intensive software reconstruction. This study aimed to formulate a deep learning model with standing posteroanterior (PA) X-rays at first clinic visit to differentiate between progressive (P) and non-progressive (NP) curves.

METHODS

For this retrospective cohort study, we identified patients presenting with AIS between October 2015 to April 2020 at our tertiary referral centre. Patients with mild curvatures (11 - 30o) who were skeletally immature (Risser sign of ≤2) were recruited. Patients receiving biplanar X-ray radiographs (EOS™) were divided between a training-cross-validation cohort (328 patients) and independent testing cohort (110 patients). Another 52 patients receiving standard PA spinal X-rays were recruited for cross-platform validation. Following 3D reconstruction, we designated the major curve apex upon PA X-rays as the region of interest (ROI) for machine learning. A self-attentive capsule network was constructed to differentiate between curves manifesting P and NP trajectories. A two-stage transfer learning strategy was introduced to pre-train and fine-tune the model. Model performance (accuracy, sensitivity, specificity) was compared to that of traditional convolutional neural networks (CNNs) and a clinical parameter-based logistic regression model.

FINDINGS

3D reconstruction identified that apical rotation of the major curve and torsion were significantly different between P and NP curve trajectories. Our predictive model utilizing an ROI centered on the major curve apex achieved an accuracy of 76.6%, a sensitivity of 75.2% and a specificity of 80.2% upon independent testing. Cross-platform performance upon standard standing PA X-rays yielded an accuracy of 77.1%, a sensitivity of 73.5% and a specificity of 81.0%. Errors in prediction occurred when the degree of apical rotation / torsion was discrepant from that of the subsequent curve trajectory but could be rectified by considering serial X-rays. Performance was superior to that of traditional CNNs as well as clinical parameter-based regression models.

INTERPRETATION

This is the first report of automated prediction of AIS curve progression based on radiomics and deep learning, towards directing treatment strategy at first visit. Patients predicted to be at-risk of progression may be counselled to receive early bracing with enforcement of treatment compliance. Over-treatment may be avoided in curves deemed to be non-progressive. Results need to be consolidated in larger sample populations of different ethnicities.

FUNDING

The Society for the Relief of Disabled Children (SRDC).

The Effectiveness of Different Concepts of Bracing in Adolescent Idiopathic Scoliosis (AIS): A Systematic Review and Meta-Analysis

Brace treatment is the most common noninvasive treatment in adolescent idiopathic scoliosis (AIS); however it is currently not fully known whether there is a difference in effectiveness between brace types/concepts. All studies on brace treatment for AIS were searched for in PubMed and EMBASE up to January 2021. Articles that did not report on maturity of the study population were excluded. Critical appraisal was performed using the Methodological Index for Non-Randomized Studies tool (MINORS). Brace concepts were distinguished in prescribed wearing time and rigidity of the brace: full-time, part-time, and night-time, rigid braces and soft braces. In the meta-analysis, success was defined as ≤5° curve progression during follow-up. Of the 33 selected studies, 11 papers showed high risk of bias. The rigid full-time brace had on average a success rate of 73.2% (95% CI 61-86%), night-time of 78.7% (72-85%), soft braces of 62.4% (55-70%), observation only of 50% (44-56%). There was insufficient evidence on part-time wear for the meta-analysis. The majority of brace studies have significant risk of bias. No significant difference in outcome between the night-time or full-time concepts could be identified. Soft braces have a lower success rate compared to rigid braces. Bracing for scoliosis in Risser 0-2 and 0-3 stage of maturation appeared most effective.

Compliance with night-time overcorrection bracing in adolescent idiopathic scoliosis: Result from a cohort follow-up

The main issue that may be encountered during brace treatment of idiopathic scoliosis is the patient's compliance. While compliance with full-time brace treatment has been well documented, compliance with night-time brace treatment has not. The main feature of night-time braces is their ability to overcorrect the scoliotic curvature, which could decrease compliance. The primary aim of this study was to evaluate objectively the compliance of patients with idiopathic scoliosis when undergoing treatment by means of a night-time overcorrection brace. Twenty patients with adolescent idiopathic scoliosis were prescribed treatment with an overcorrection brace for 8 h per night. Compliance was determined by the percentage of actual hours the brace was worn relative to the prescribed regimen. Compliance was measured during 1 year via a hidden temperature monitor embedded within the brace. Patients were informed that their compliance was monitored. The brace acceptance period and the full acceptance period were analysed, and correlations were measured. The average compliance (% wearing hours/prescribed regimen) was 90.7%; 45% of the participants met or exceeded the prescribed brace time. Three girls were lost to follow-up. The mean acceptance period was 22,8 days, and half of the patients succeeded in achieving the acceptance period in less than 7 days. The mean full acceptance period was 26,9 days. The acceptance period was significantly and negatively correlated with the mean wearing time (r = -0,61, P = 0,004). There was no correlation between the in-brace overcorrection and the wearing time. These results suggest that patients with an overcorrection night-time brace had good compliance. The overcorrection did not seem to influence compliance. The first weeks of treatment seemed to be crucial for treatment compliance.

Factors That Influence In-Brace Correction in Patients with Adolescent Idiopathic Scoliosis

OBJECTIVE

To identify the factors affecting in-brace correction in patients with adolescent idiopathic scoliosis (AIS).

METHODS

We performed a retrospective analysis of patients with AIS receiving Gensingen brace treatment in our scoliosis center from July 2015 to October 2017 was performed. The selection of patients was in accordance with the Scoliosis Research Society inclusion criteria for a bracing study. Some radiographic and clinical parameters, including the Cobb angle, rib-vertebra angle difference, coronal and sagittal balance, lumbar-pelvic relationship (LPR), Risser sign, curve type, age, gender, height, weight, body mass index, and menstrual status were collected. The correlation and difference analyses were performed to identify the factors influencing in-brace correction.

RESULTS

A cohort of 112 patients with AIS (94 girls and 18 boys) were included in the present study. The mean in-brace correction was 59.29% ± 22.33% (range, 16.22%-100.00%). In-brace correction showed a significantly negative correlation with the major curve Cobb angle, minor curve Cobb angle, total curve Cobb angle, and LPR (P < 0.05 for all). Sagittal and coronal imbalance could reduce the curve correction (P < 0.001 and P = 0.008, respectively). The remaining parameters were not related to in-brace correction.

CONCLUSIONS

In-brace correction in the present study was 59.29% ± 22.33% (range, 16.22%-100.00%). Some factors, including the Cobb angle, sagittal and coronal balance, and LPR, have an effect on in-brace correction. The results from the present study can provide some useful information for brace design and fabrication.