It's not just the big kids: both high and low BMI impact bracing success for adolescent idiopathic scoliosis

BrAIST-Calc: Prediction of Individualized Benefit From Bracing for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Prospective multicenter study data were used for model derivation and externally validated using retrospective cohort data.

OBJECTIVE

Derive and validate a prognostic model of benefit from bracing for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

The Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) demonstrated the superiority of bracing over observation to prevent curve progression to the surgical threshold; 42% of untreated subjects had a good outcome, and 28% progressed to the surgical threshold despite bracing, likely due to poor adherence. To avoid over-treatment and to promote patient goal setting and adherence, bracing decisions (who and how much) should be based on physician and patient discussions informed by individual-level data from high-quality predictive models.

MATERIALS AND METHODS

Logistic regression was used to predict curve progression to <45° at skeletal maturity (good prognosis) in 269 BrAIST subjects who were observed or braced. Predictors included age, sex, body mass index, Risser stage, Cobb angle, curve pattern, and treatment characteristics (hours of brace wear and in-brace correction). Internal and external validity were evaluated using jackknifed samples of the BrAIST data set and an independent cohort (n=299) through estimates of discrimination and calibration.

RESULTS

The final model included age, sex, body mass index, Risser stage, Cobb angle, and hours of brace wear per day. The model demonstrated strong discrimination ( c -statistics 0.83-0.87) and calibration in all data sets. Classifying patients as low risk (high probability of a good prognosis) at the probability cut point of 70% resulted in a specificity of 92% and a positive predictive value of 89%.

CONCLUSION

This externally validated model can be used by clinicians and families to make informed, individualized decisions about when and how much to brace to avoid progression to surgery. If widely adopted, this model could decrease overbracing of AIS, improve adherence, and, most importantly, decrease the likelihood of spinal fusion in this population.

Clinical Outcomes of 111 Patients with Early Onset Idiopathic Scoliosis (EOIS) Receiving Brace Treatment: A Longitudinal Retrospective Cohort Study

Introduction: Bracing is one of the first-line treatment for early-onset idiopathic scoliosis (EOIS) to control curves from progression. This study aimed to explore the determinants that govern bracing effectiveness in EOIS. Methods: One hundred and eleven patients with EOIS (mean age of 8.6 ± 1.25 at diagnosis) received bracing treatment and had a final follow-up beyond skeletal maturity were identified from records between 1988 and 2021. Demographic data and clinical features of spinal curvature were obtained for correlation analyses to determine the associations between curve outcomes and clinical features. Results: Most patients were female (85.6%) and had a major curve on the left side (67%). The mean baseline Cobb angle of major curves was 21.73 ± 7.92°, with a mean Cobb angle progression of 18.05 ± 19.11°. The average bracing duration was 5.3 ± 1.9 years. Only 26 (23.4%) of them underwent surgery. The final Cobb angle and curve progression at the final follow-up with a Cobb angle of ≥50° were positively correlated with the initial Cobb angle (r = 0.206 and r = 0.313, respectively) and negatively correlated with maturity parameters. The lumbar curve type was found to correlate with a smaller final Cobb angle. Conclusions: The majority of patients had a final Cobb angle < 50°, which was considered a successful bracing outcome. The final Cobb angle correlated with the initial Cobb angle and curve types observed in EOIS.

Association of success of brace treatment and various aspects of in-brace correction in patients with adolescent idiopathic scoliosis

BACKGROUND

Although skeletal maturity and brace wear time contribute to the success of brace treatment in adolescent idiopathic scoliosis (AIS), the extent of initial in-brace correction for ensuring successful outcomes remains unclear. We hypothesized that the degree of initial in-brace correction correlates with brace success in patients with AIS.

METHOD

The study included 135 AIS patients with a major Cobb angle of 20°-40° treated with a thoracic lumbosacral orthosis for at least one year and followed up for skeletal maturity. The subjects were divided into two groups: the skeletally immature group (group I, n = 72), who met the Bracing in Adolescent Idiopathic Scoliosis Trial study protocol at the start of brace treatment, and the skeletally mature group (group M, n = 63). Treatment success was defined as not needing surgical treatment and a major Cobb angle <40° at the end of brace treatment.

RESULTS

In both groups, the mean major Cobb angles before treatment, while wearing the brace, and at the end of brace treatment were 30.6°/31.7°, 22.9°/24.2°, and 38.8°/33.9° (p < 0.05), respectively, and the treatment success rate was 56.9% and 77.8%, respectively (p < 0.05). Univariate regression analysis revealed the following risk factors: Risser grade 0 in group I, major Cobb angles before treatment, initial in-brace major Cobb angle, and in-brace correction rate in both groups. Cutoff values of in-brace major Cobb angle for treatment success calculated by ROC curve in groups I and M were 24° and 29°, respectively.

CONCLUSIONS

In-brace major scoliosis correction of <25° in patients with immature skeletal status and <30° in patients with mature skeletal structure should be aimed at to achieve significant brace treatment success.

The Sanders Classification and Obesity: Do Obese Kids With AIS Present With More Advanced Skeletal Maturity?

INTRODUCTION

Obese and overweight (OOW) patients with adolescent idiopathic scoliosis (AIS) have been shown to initially present with a more advanced Risser score compared to normal weight (NW) patients. The Sanders Maturity Scale (SMS) is now more commonly used by surgeons to assist with treatment decisions because it more reliably predicts skeletal maturity. However, the relationship between SMS and obesity has not been described. We hypothesize that in patients with AIS, OOW patients will have a higher SMS score on initial presentation when compared to NW patients.

METHODS

Billing data from 2 different institutions were used to identify patients with AIS presenting to a pediatric orthopaedic spine surgeon for an initial visit between July 2012 and March 2020. We excluded those without height/weight data, spine radiographs, or left-hand radiographs for measuring SMS stage. Body mass index-for-age percentiles were calculated and used to group patients into NW (<85th percentile) or OOW (85th percentile and above) per Centers for Disease Control guidelines. After collecting preliminary data, a power analysis was performed using average SMS scores between NW and OOW patients with an alpha of 0.5, determining a needed sample size of approximately 300 male and 300 female subjects.

RESULTS

Five hundred ninety patients (296 female, 294 male) were identified. The SMS stage at presentation was significantly greater in OOW compared to NW patients for both females (5.9±1.8 vs. 5.2±1.7; P =0.003) and males (4.9±1.9 vs. 4.1±1.8; P =0.002). The major curve magnitude for OOW females was significantly different from NW females (36±16 degrees vs. 30±16 degrees; P =0.004). The major curve magnitude was not different for OOW and NW males ( P =0.3).

CONCLUSION

At initial presentation, OOW patients present at a greater skeletal maturity as measured by the SMS compared with NW patients. OOW female patients present with a greater major curve magnitudes than NW female patients. These results highlight negative implications of the pediatric obesity epidemic as it relates to the AIS population. These findings can be used to counsel families and provide anticipatory guidance for the AIS treatment plan.

LEVEL OF EVIDENCE

Level III-cross-sectional study.

Does in-brace correction affect coronal spinal and thoracic cage parameters in individuals with idiopathic scoliosis? A retrospective cohort study

The aim of the study is to identify the effects of in-brace correction on coronal spinal and thoracic cage parameters in individuals with idiopathic scoliosis (IS). The coronal spinal parameters [Cobb angle, apical vertebral rotation (AVR), lateral trunk shift, coronal alignment, biacromial slope and pelvic asymmetry] and the thoracic cage parameters [T1- 12 height, T1-S1 height, thoracic transverse diameter, and apical vertebral body-rib ratio (AVB-R)] of 89 child and adolescent patients were measured on posterior-anterior full-spine radiographs at pre-brace and in-brace conditions using Surgimap software. The initial in-brace correction (IBC) was calculated as a percentage decrease in the Cobb angle on the in-brace radiographs. The mean IBC rate for the primary curve was 37% (range = 10-100%). In the in- brace condition, the Cobb angle (p<0.001), AVR (p<0.001) and lateral trunk shift (p<0.001) decreased significantly; no statistically significant difference was found in the biacromial slope (p=0.713) and the coronal alignment (p=0.074). The T1-12 height and the T1-S1 height increased significantly (p<0.001) whereas the thoracic transverse diameter and the AVB-R decreased significantly (p<0.001). Unlike IBC rate was below 30% as IBC rate was above 30%, the T1-12 height (p<0.001) increased and the AVB-R decreased (p<0.001). The bracing improved the lateral trunk shift, the AVB-R, the thoracic and spine heights, but decreased the thoracic transverse diameter. The thoracic cage parameters may be better when the IBC rate is above 30%.

Outcome of Conservative Therapy of Adolescent Idiopathic Scoliosis (AIS) with Chêneau-Brace

Chêneau-brace (C-Brace) is a potential tool for the treatment of adolescent idiopathic scoliosis (AIS) with a Cobb angle between 20° and 45° for the primary curve. The aim of the present study was (1) to estimate study cohorts with C-brace therapy success and therapy failure and (2) to analyze possible factors that influence the therapy outcome. Seventy-eight patients with AIS were assessed before the initiation of C-brace treatment. Each patient underwent radiography examinations before the brace, in-brace, and at the therapy end. Cobb angle was considered as increased when the value at the end of therapy was increased more than 5° (Δ > 5°), unchanged—when the value was unchanged within ± 5° and decreased- when the value was decreased more than 5° (Δ < −5°). The study cohort was stratified due to curve topography in the thoracic, thoracolumbar, and lumbar scoliosis groups. Global analysis revealed no statistically significant modification of the Cobb angle (Cobb angle pre-brace vs. Cobb angle post-brace: 30.8° ± 8.2 vs. 29.3° ± 15.2, p = 0.26). However, at the end of C-brace therapy, the primary Cobb angle was decreased by more than 5° in 27 patients (35%), unchanged (Δ within the range of ±5°) in 36 patients (46%), and increased more than 5° in 15 patients (19%). Sub-group analysis due to curve topography and skeletal maturity has shown higher rates of brace therapy failure in thoracic curves and in younger patients (Risser grade 0). Patients with higher Cobb angle correction with C-brace had lower rates of therapy failure. The C-brace can be useful for the prevention of scoliotic curve progression in patients with AIS. However, many factors influence the therapy effect.

Compliance with wearing a thoracolumbar orthosis in nonoperative treatment of osteoporotic vertebral fractures: a prospective sensor-controlled study

BACKGROUND CONTEXT

Hyperextension orthoses (HOs) for nonoperative treatment of osteoporotic vertebral fractures (OVFs) are widely prescribed. However, the compliance, how much an HO is worn after it has been prescribed, is widely unknown.

PURPOSE

This study was performed to assess the wearing time of HOs for OVFs in a prospective blinded, sensor-controlled manner.

STUDY DESIGN / SETTING

A prospective, single blinded observational study was performed.

PATIENT SAMPLE

This study prospectively included 18 patients who were treated nonoperatively with an HO for OVFs.

OUTCOME MEASURES

The true wearing time was measured using a hidden temperature-based sensor. The patients were invited to return for regular follow-up every 2 weeks for 6 weeks, at which time clinical evaluation (including a visual analog scale for pain and the Oswestry disability questionnaire) and radiographs of the spine were performed.

METHODS

Full compliance was defined as a wearing time of 15 hours per day. Correlation between compliance and demographic differences, patient reported outcomes and radiographic changes of the vertebral structures were calculated.

RESULTS

The mean HO wearing time was 5.5±3.3 hours (37%±22% compliance). Female patients used the HO significantly longer per day than did male patients (6.5±3.2 vs 2.9±2.0 hours, p=.039). Age and body mass index had no influence on wearing behavior.

CONCLUSIONS

Overall, compliance with wearing HOs is poor and shows great variability with significant gender-dependency but not associated with BMI, age, or pain-level. Further studies are required to confirm our results that the wearing time does not have an influence on kyphotic progression of the osteoporotic fractured segment, nor on clinical outcome at short term.

LEVEL OF EVIDENCE

I.

Association between body mass index and posterior spine fusion among patients with adolescent idiopathic scoliosis

INTRODUCTION

Previous studies have found mixed associations between body mass index (BMI) and adolescent idiopathic scoliosis (AIS) incidence and progression. The aim of this study was to examine the association between BMI and the incidence of posterior spine fusion (PSF) among pediatric patients with AIS.

METHODS

This was a retrospective cohort study of patients diagnosed with AIS at a single large tertiary care center between January 1, 2014 and December 31, 2020. BMI-for-age percentiles were used to categorize BMI into four categories: underweight (<5th percentile), healthy weight (≥5th to <85th percentile), overweight (≥85th to <95th percentile), and obese (≥95th percentile). Chi-square and t-tests were used to compare distributions of baseline characteristics by incident PSF outcome status. Multivariable logistic regression assessed the association between BMI category at baseline and incident PSF adjusting for sex, age at diagnosis, race/ethnicity, health insurance type, vitamin D supplementation, and low vitamin D levels.

RESULTS

A total of 2,258 patients met the inclusion criteria with 2,113 patients (93.6%) who did not undergo PSF during the study period and 145 patients (6.4%) who did undergo PSF. At baseline, 7.3% of patients were categorized as underweight, 73.2% were healthy weight, 10.2% were overweight, and 9.3% were obese. Compared to those in the healthy weight group, there was no significant association between PSF and being underweight (adjusted odds ratio [AOR] 1.64, 95% CI 0.90-2.99, p = 0.107), being overweight (AOR 1.25, 95% CI 0.71-2.20, p = 0.436), or being obese (AOR 1.19, 95% CI 0.63-2.27, p = 0.594).

CONCLUSIONS

This study did not find a statistically significant association between underweight, overweight, or obese BMI category and incident PSF among patients with AIS. These findings add to the current mixed evidence on the relationship between BMI and surgical risk and may support the recommendation of conservative treatment to patients regardless of BMI.

Effect of Body Mass Index Percentile on Clinical and Radiographic Outcome and Risk of Complications after Posterior Instrumented Fusion for Adolescent Idiopathic Scoliosis: A Retrospective Cohort Study

BACKGROUND

The aim of this study is to evaluate the effect of body mass index percentile (BMI%) at postoperative and medium follow-up in AIS patients undergoing posterior instrumented fusion (PSF).

METHODS

We analyzed 87 clinical records of patients (19 male, 68 female) who underwent PSF. The patients were divided into four groups considering BMI%: underweight (UW), normal weight (NW), overweight (OW), and obesity (OB). Demographic, clinical (SRS-22), and radiographic data were collected. The primary outcome was to assess both the surgical and clinical outcomes, whilst the secondary outcome was to compare the radiological findings among the studied groups. Follow-ups were set preoperatively, at 6 months and 5 years.

RESULTS

Our results did not show significant differences of clinical outcomes among the studied groups, except for a longer surgical time and a higher hemoglobin decrease in UW and OB patients (p = 0.007). All BMI categories showed similar radiographic outcomes, with no statistical significance at final follow-up. OB patients showed a worse percentage of major curve correction compared to baseline and to UW and OW patients.

CONCLUSIONS

The present study does not underline substantial differences in clinical and radiographic results among any of the studied groups. However, UW and OB patients showed a worse postoperative progress. Counseling should be provided for patients and families and the achievement of a normal BMI% should be recommended.

Ethnic Disparity in the Incidence of Scoliosis Among Adolescents in Tianzhu Tibetan Autonomous County, China

Objectives

To determine the influence of ethnic disparities, socioeconomic status (SES) and hukou on the incidence of scoliosis.

Methods

We enrolled 2,445 junior high school students (Han: 1,153; ethnic minorities: 1,292) aged 12–16 years from two schools in Tianzhu Tibetan Autonomous County, Gansu Province from November 2020 to February 2021. We measured the angle of trunk rotation (ATR) using a scoliometer. Two-factor analysis of variance was used to comparatively analyze differences in the ATR according to ethnicity, age, sex, body mass index (BMI), and SES between the groups. Associations between risk factors and scoliosis were estimated using odds ratios and 95% confidence intervals with an unconditional multivariate logistic regression model for the two groups.

Results

Adolescents with Han ethnicity were more likely to have scoliosis than their ethnic minority counterparts (10.8% vs. 7.1%, P < 0.05). The ATR value in the Han group decreased with age whereas the minority group showed an upward trend (P < 0.05). The difference between ethnic groups was not significant, only at level 3. In particular, the ATR values among Han girls were significantly higher than those of ethnic minority girls (P < 0.05). Compared with Han adolescents, the BMI of ethnic minorities had a greater impact on the ATR. A statistically significant difference in SES was found between the two ethnic groups (P < 0.05). Hukou and parents' occupation had an important influence on the onset of scoliosis.

Conclusions

Han adolescents had higher ATR values and were more likely to have scoliosis than ethnic minority adolescents in our study. Growth and development indicators (height and BMI) and differences in SES between the two groups played an important role.

Evaluation of In-brace Correction in Individuals with Adolescent Idiopathic Scoliosis: A Retrospective and Descriptive Study

Introductions: Achieving maximum correction at the beginning of brace treatment in AIS is the only factor that can be controlled by the bracing provider if we have a better understanding of the prognostics and factors associated with achieving in-brace correction. The aim of this present study was to evaluate in-brace correction in a cohort of AIS patients who were treated by full-time bracing with plastic moulded thoraco-lumbo-sacral spinal orthosis (TLSO). Methods: This study was a retrospective descriptive study. We collected data from medical records of individuals with AIS who receiving full-time braces treatment from Orthotic Clinic, King Chulalongkorn Memorial Hospital. Demographic data included age, gender, weight, height, and body mass index (BMI). Cobb angle, Risser sign, and curve type were determined using pre and post-brace standing posteroanterior (PA) radiographs. Correlation analysis was performed to investigate in-brace correction with associated factors.  Results: We included 91 patients' data and radiographic images with AIS, with seven (7.69%) boys and 84 (92.31%). The overall mean Cobb angle was 32.9 ± 8.5º, and during brace treatment, it was 22.5 ± 11.5º. There was a significant mean difference in the mean Cobb angle before and in-brace (p < 0.001). The overall mean in-brace correction in the study was 34.1 ± 22.7%. Initial Cobb angle and BMI were found to be significantly negatively associated with in-brace correction with a Pearson coefficient of -0.49 and -0.24, respectively. Conclusion: The mean of first in-brace correction TLSO was 34.1% from the initial Cobb angle. No difference in in-brace correction across curve types in our study. There was a significant Cobb angle changed before and in-brace radiograph. We found that in-brace correction was significantly associated with initial Cobb angle and BMI. Keywords: Adolescent Idiopathic Scoliosis, in-brace correction, bracing

Association of FBN1 polymorphism with susceptibility of adolescent idiopathic scoliosis: a case-control study

BACKGROUND

Fibrillin-1 (FBN1) is an extracellular matrix glycoprotein essential to the structural component of microfibrils and FBN1 gene polymorphisms can be associated with adolescent idiopathic scoliosis (AIS) susceptibility. This study aimed to evaluate the potential role of the FBN1 rs12916536 polymorphism in AIS development or severity and the variation in Cobb angle in relation to patient's characteristics.

METHODS

DNA from 563 subjects (185 AIS patients and 378 controls) were genotyped using a validated TaqMan allelic discrimination assay. A multivariate logistic regression model evaluated the association between polymorphism and AIS, using the adjusted odds ratios (OR) with their respective 95% confidence intervals (95% CI). A linear regression analysis evaluated the variation in Cobb angle according to the patient's age and body mass index (BMI).

RESULTS

Among the AIS group there was a predominance of females (12:1), low or normal BMI (90%), 58% had a Cobb angle greater than 45° and 74% were skeletally mature. Age was a risk factor (4-fold) for curve progression higher than BMI (P < 0.001). The allelic frequency of the rs12916536 G > A polymorphism was 40% in controls and 31% in AIS cases; and this difference was statistically significant (P = 0.004). FBN1 rs12916536 GA + AA genotypes were associated with a lower risk of AIS susceptibility (OR = 0.58 and 95% CI = 0.35-0.98), after adjustment for age, sex and BMI. However, no significant differences were detected in polymorphism distribution with the severity of the disease (Cobb < 45° or ≥ 45°).

CONCLUSION

Age was a risk factor for progression of the scoliotic curve and FBN1 rs12916536 polymorphism a protective factor for AIS susceptibility.

Predictive Factors on Initial in-brace Correction in Idiopathic Scoliosis: A Systematic Review

STUDY DESIGN

Systematic literature review.

OBJECTIVE

The aim of this study was to systematically review the literature and provide an overview of reported predictive factors on initial in-brace correction in patients with idiopathic scoliosis (IS).

SUMMARY OF BACKGROUND DATA

Brace therapy is the best proven non-surgical treatment for IS. There is strong evidence that lack of initial in-brace correction is associated with brace treatment failure. To improve initial in-brace corrections and subsequently long-term brace treatment success, knowledge about factors influencing initial in-brace correction is a prerequisite.

METHODS

A systematic literature search was performed in Pubmed, Embase, Web-of-Science, Scopus, Cinahl, and Cochrane in November 2020. Studies which reported factors influencing initial in-brace correction in IS patients treated with brace therapy were considered eligible for inclusion.

RESULTS

Of the 4562 potentially eligible articles identified, 28 studies fulfilled the inclusion criteria and were included in this systematic review. Nine studies (32%) were classified as high quality studies and the remaining 19 studies (68%) as low quality. Thirty-four different reported factors were collected from the included studies. Strong evidence was found for increased curve flexibility as favorable predictive factor for initial in-brace correction. Moderate evidence was found for thoracolumbar or lumbar curve pattern as favourable predictive factor, and double major curve pattern as unfavourable predictive factor for initial in-brace correction. Also moderate evidence was found that there is no significant difference on initial in-brace correction between computer-aided design and manufacturing systems (CAD/CAM) braces with or without finite element models (FEM) simulation, and braces fabricated using the conventional plaster-cast.

CONCLUSION

The results of this systematic review indicate that increased curve flexibility is strongly associated with increased initial in-brace correction.Level of Evidence: 1.

Supine correction index as a predictor for brace outcome in adolescent idiopathic scoliosis

Aims

The aim of this study was to assess the ability of morphological spinal parameters to predict the outcome of bracing in patients with adolescent idiopathic scoliosis (AIS) and to establish a novel supine correction index (SCI) for guiding bracing treatment.

Methods

Patients with AIS to be treated by bracing were prospectively recruited between December 2016 and 2018, and were followed until brace removal. In all, 207 patients with a mean age at recruitment of 12.8 years (SD 1.2) were enrolled. Cobb angles, supine flexibility, and the rate of in-brace correction were measured and used to predict curve progression at the end of follow-up. The SCI was defined as the ratio between correction rate and flexibility. Receiver operating characteristic (ROC) curve analysis was carried out to assess the optimal thresholds for flexibility, correction rate, and SCI in predicting a higher risk of progression, defined by a change in Cobb angle of ≥ 5° or the need for surgery.

Results

The baseline Cobb angles were similar (p = 0.374) in patients whose curves progressed (32.7° (SD 10.7)) and in those whose curves remained stable (31.4° (SD 6.1)). High supine flexibility (odds ratio (OR) 0.947 (95% CI 0.910 to 0.984); p = 0.006) and correction rate (OR 0.926 (95% CI 0.890 to 0.964); p < 0.001) predicted a lower incidence of progression after adjusting for Cobb angle, Risser sign, curve type, menarche status, distal radius and ulna grading, and brace compliance. ROC curve analysis identified a cut-off of 18.1% for flexibility (sensitivity 0.682, specificity 0.704) and a cut-off of 28.8% for correction rate (sensitivity 0.773, specificity 0.691) in predicting a lower risk of curve progression. A SCI of greater than 1.21 predicted a lower risk of progression (OR 0.4 (95% CI 0.251 to 0.955); sensitivity 0.583, specificity 0.591; p = 0.036).

Conclusion

A higher supine flexibility (18.1%) and correction rate (28.8%), and a SCI of greater than 1.21 predicted a lower risk of progression. These novel parameters can be used as a guide to optimize the outcome of bracing.

Cite this article: Bone Joint J 2022;104-B(4):495–503.

Polymorphisms in paired box 1 gene were associated with susceptibility of adolescent idiopathic scoliosis: A case–control study

Background

Objectives:

Settings and Design:

Materials and Methods:

Statistical Analysis:

Results:

Conclusions:

Lack of in-brace x-rays in compliant AIS patients wearing full-time TLSO braces associates with failure

Background

In-brace correction and brace compliance with thoraco-lumbo-sacral orthotic (TLSO) braces are associated with successful treatment of adolescent idiopathic scoliosis (AIS). This paper compares patients who had consistent radiographic documentation of in-brace correction to those who did not.

Methods

All skeletally immature (Risser 0-2) patients were treated for AIS (25-45°) with full-time TLSO braces that had compliance temperature monitors. All patients wore their braces at least 12 h a day. Brace failure was defined as curve progression to a surgical magnitude (≥ 50°). All patients were followed until brace discontinuation.

Results

Ninety patients (F 82, M 8) with an average age of 12.1 (10.1-15.0) years, Risser grade 0 (0-2), BMI percentile 48.5 (0.0-98.8), and daily brace wear of 16.5 (12.1-21.6) h/day were treated for 24.3 (8.0-66.6) months. Patients went through 1.7 (1-4) braces on average. Forty-two out of 90 (46.7%) patients had some amount of brace time with an unknown in-brace correction, which, on average, was 66.1% of their total treatment course (11.5-100). On univariate analysis, patients that did not have a repeat in-brace x-ray with major brace adjustments or new brace fabrication tended to be more skeletally immature (Risser 0 and tri-radiate open, p = 0.028), wear more braces throughout their treatment (2.0 vs 1.4, p < 0.001), were treated for a longer period of time (27 vs 22 months, p = 0.022), and failed bracing more often (47.6% vs 22.9%, p = 0.014).

Conclusions

Patients who did not have new in-brace x-rays with major brace adjustments and/or new brace fabrication were 3.1 (95% CI 1.2-7.6) times more likely to fail bracing than patients who were re-checked with new in-brace x-rays.

Trial registration

ClinicalTrials.gov—NCT02412137, initial registration date April 2015

Level of evidence

III

Impact of body mass index on the initial in-brace correction in patients with idiopathic scoliosis

Background/Aim: Many factors affect initial in-brace correction and treatment outcome in patients with idiopathic scoliosis. Previous studies have observed contradictory results on the role of BMI in orthotic treatment. The aim of this study was to examine whether BMI impacts in-brace correction, isolated and in relation to other predictive factors (curve magnitude, curve location and Risser sign). Methods: A retrospective study has been conducted on patients with idiopathic scoliosis treated with Cheneau-Sobernheim brace, that had no prior treatment. The collected and analysed data included patient demographics, BMI percentile and radiological parameters (curve magnitude in Cobb angle, curve location, Risser sign). The initial in-brace correction was expressed as a percentage of Cobb angle reduction in the brace as opposed to Cobb angle out of brace. Patients were categorised into groups according to their BMI, expressed in percentiles, ie: low BMI (< 5 percentiles), normal BMI (5-85 percentiles) and high BMI (> 85 percentiles). To determine the significant difference and correlation relationship between the examined variables, variance tests, t-test with unequal variance, and Pearson correlation coefficient have been used. Results: The cohort study comprised 213 patients (170 females and 43 males) with a mean age of 13.5 years at brace prescription. Low BMI has been detected in 10 % patients, normal BMI in 78 % and high BMI in 10 % patients. No significant difference in in-brace correction has been found between BMI groups, nor has there been any significant correlation between BMI and in-brace correction. Regarding other factors, significant difference within BMI groups was found between in-brace correction and curve location, as well as in-brace correction and Risser sign. Lumbar curves had significantly better in-brace correction than thoracic curves. Significant correlations between in-brace correction and curve magnitude, curve location and Risser sign were detected. Conclusion: The results of the present study show that, as an independent factor, BMI does not impact in-brace correction. Other factors, such as curve magnitude, curve location and Risser sign, play a more significant role in the orthotic treatment of patients with idiopathic scoliosis.

Body Posture Defects and Body Composition in School-Age Children

The aim of the study was to assess the relationship between the shape of the anteriorposterior spinal curvature and body composition in schoolchildren. The study included 257 children, aged 11–12. Correct spinal curvature was established in 106 (41.08%) subjects. Other types included: decreased kyphosis and correct lordosis—40 participants (15.50%), correct kyphosis and decreased lordosis—24 individuals (9.30%), increased kyphosis and correct lordosis—17 subjects (6.59%), correct kyphosis and increased lordosis—22 children (8.53%), decreased kyphosis and decreased lordosis—32 people (12.40%), decreased kyphois and increased lordosis—four of the examined subjects (1.55%) increased kyphosis and lordosis—13 people (5.04%). In addition, 134 (51.94%) demonstrated scoliotic posture and eight (3.10%) scoliosis. There were significant relationships between the shape of the anteriorposterior curvatures and body composition in schoolchildren. Those with a strong body build (predominance of mesomorphs) were generally characterised by the correct formation of these curvatures. In contrast, lean subjects (with the predominance of ectomorphic factors) were more likely to experience abnormalities. No correlations with body composition were observed in the group with scoliotic posture or scoliosis. Both in the prevention and correction of postural defects, one should gradually move away from one-sided, usually one-system, therapeutic effects. An approach that takes into account both somatic and neurophysiological factors seems appropriate. With the correct body composition and structure, shaping the habit of correct posture is much easier.

It is not just about the frontal plane: sagittal parameters impact curve progression in AIS patients undergoing brace treatment

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The purpose of this study was to explore the association between pre-brace and in-brace sagittal parameters and curve progression. To date, there has been no published research focused on spinopelvic sagittal parameters and bracing outcomes in AIS. We hypothesize that sagittal spinopelvic parameters are associated with curve progression at 2 years.

METHODS

This study included AIS patients with a pre-brace (PB) major curve between 20° and 45°. The outcome was defined as > 10° curve progression or surgery within 2 years of brace initiation. Spinopelvic parameters included C7-Central Sacral Vertebral Line shift (C7-CSVL), thoracic trunk shift, lumbar lordosis (LL), pelvic incidence (PI), T2-T12 thoracic kyphosis (TK) pelvic incidence-lumbar lordosis (PI-LL) mismatch, sagittal vertical axis (SVA), and pelvic tilt (PT).

RESULTS

Of 50 patients included in this review, [70% Rigo (RCSO) and 30% Boston (BSO)], 16 (32%) patients demonstrated progression (23% of patients with RCSO vs 53% with BSO; p = 0.034). In patients with more than 30% major coronal curve correction (CCC), 23% had progression. 45% of patients progressed when they achieved ≤ 30% correction (p = 0.108). Among PB sagittal parameters and adjusting for coronal curve, patients with an abnormal PB SVA had 3.1 times increased risk of treatment failure compared with patients who had a normal PB SVA. Patients with PB hypo-LL had a 2.8 times increased risk of treatment failure compared with patients who had normal or hyper-LL. Among IB sagittal parameters, patients who had a normal PB PI-LL had a 3.9 times increased risk of treatment failure when they became mismatched in-brace (IB). Patients who had normal pre-brace kyphosis who became hypo-kyphotic IB had an 8.4 times increased risk of treatment failure compared with patients who maintained normal TK or became hyper-kyphotic.

CONCLUSION

These data suggest that we should pay careful attention to sagittal parameters prior to and during brace treatment as braces can control these parameters.

LEVEL OF EVIDENCE

Level III.

Adolescent Idiopathic Scoliosis Bracing Success Is Influenced by Time in Brace: Comparative Effectiveness Analysis of BrAIST and ISICO Cohorts

STUDY DESIGN

Comparative effectiveness study OBJECTIVE.: To evaluate factors leading to higher percentage of brace failures in a cohort of North American patients with adolescent idiopathic scoliosis relative to their peers in Italy.

SUMMARY OF BACKGROUND DATA

Studies of bracing in United States have shown worse outcomes than studies from European centers, possibly due to sample characteristics or treatment approaches.

METHODS

Sample: Braced patients, aged 10 to 15, Risser <3, Cobb 20°- to 40°, observed to Cobb ≥40° and/or ≥Risser 4 selected from prospective databases. Comparators: Bracing per Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) (TLSO) and Italian Scientific Spine Institute (ISICO) protocol (SPoRT braces with or without SEAS exercises). Baseline characteristics (sex, age, BMI, Risser, Cobb, curve type) and average hours of brace wear/day. Differences in programs (e.g., SEAS, type of brace, weaning protocol) were captured by a variable named "SITE."

OUTCOME

Treatment failure (Cobb ≥40 before Risser 4).

STATISTICS

Comparison of baseline characteristics, analyses of risk factors, treatment components, and outcomes within and between cohorts using logistic regression.

RESULTS

A total of 157 BrAIST and 81 ISICO subjects were included. Cohorts were similar at baseline but differed significantly in terms of average hours of brace wear: 18.31 in the ISICO versus 11.76 in the BrAIST cohort. Twelve percent of the ISICO and 39% of the BrAIST cohort had failed treatment. Age, Risser, Cobb, and a thoracic apex predicted failure in both groups. SITE was related to failure (odds ratio [OR] = 0.19), indicating lower odds of failure with ISICO versus BrAIST approach. With both SITE and wear time in the model, SITE loose significance. In the final model, the adjusted odds of failure were higher in boys (OR = 3.34), and those with lowest BMI (OR = 9.83); the odds increased with the Cobb angle (OR = 1.23), and decreased with age (OR = 0.41) and hours of wear (OR = 0.86).

CONCLUSION

Treatment at the ISICO resulted in a lower failure rate, primarily explained by longer average hours of brace wear.

LEVEL OF EVIDENCE

3.

The Influence of Body Habitus on Documented Brace Wear and Progression in Adolescents With Idiopathic Scoliosis

BACKGROUND

Although studies have been published stating obese patients are less compliant with brace use, no objective studies measuring hours of daily brace wear have been performed to correlate brace wear and success with body mass index (BMI). The purpose of this study was to establish the relationship between BMI and brace compliance, and between BMI and progression to surgical magnitude of 50 degrees or more.

METHODS

A total of 175 adolescents were prescribed thoracolumbarsacral orthosis for the treatment of an adolescent idiopathic scoliosis and followed to completion of treatment. BMI was measured at brace prescription, and divided into: (1) underweight (< 5th percentile), (2) normal (>5th, <85%), (3) overweight (>85%, <95%), and (4) Obese (>95%). Thermochron sensors were used to measure compliance. Radiographs were measured at brace prescription, and at time of brace discontinuation or surgery. Outcome was classified as successful if curve magnitude was <50 degrees and no surgery was performed.

RESULTS

The underweight group wore their braces more hours than the other groups (15.7 h low, 12.5 h normal, 11.7 h high, and 9.0 h obese BMI (low vs. normal P=0.031, low vs. high P=0.01, low vs. obese P=0.01). The underweight group had the highest rate of surgical progression (60%), compared with 27.7% of normal BMI teens, 28.6% of overweight patients, and 55.6% of obese patients. The low BMI had a significantly higher rate of surgery than the normal BMI group (P=0.01).

CONCLUSIONS

Although overweight and obese patients wear orthoses the least hours daily, the highest surgical risk is in underweight adolescents despite good compliance.

LEVEL OF EVIDENCE

Level 2.

Brace treatment in adolescent idiopathic scoliosis: risk factors for failure-a literature review

Brace treatment is the most common nonoperative treatment for the prevention of curve progression in adolescent idiopathic scoliosis. The success reported in level 1 and 2 clinical trials is approximately 75%. The aim of this review was to identify the main risk factors that significantly reduce success rate of brace treatment. A literature search using the MEDLINE and Embase databases was conducted. Studies were included if they identified specific risk factor(s) for curve progression. Studies that looked at nighttime braces, superiority of one type of brace over another, the effect of physical therapy on brace performance, cadaver or nonhuman studies were excluded. A total of 1,022 articles were identified of which 25 met all of the inclusion criteria. Seven risk factors were identified: Poor brace compliance (eight studies), lack of skeletal maturity (six studies), Cobb angle over a certain threshold (six studies), poor in-brace correction (three studies), vertebral rotation (four studies), osteopenia (two studies), and thoracic curve type (two studies). Three risk factors were highly repeated in the literature which identified specific subgroups of patients who have a much higher risk to fail brace treatment and to progress to fusion. This data demonstrates that 60% to 70% of the patients referred to bracing are Risser 0 and 30% to 70% of this group will not wear the brace enough to ensure treatment efficacy. Furthermore, Risser 0 patients who reach the accelerated growth phase with a curve ≥40° are at 70% to 100% risk of curve progression to the fusion surgical threshold despite proper brace wear. Skeletally immature patients with relatively large magnitude scoliosis who are noncompliant are at a higher risk of failing brace treatment.

Bracing In The Treatment Of Adolescent Idiopathic Scoliosis: Evidence To Date

Brace effectiveness for adolescent idiopathic scoliosis was controversial until recent studies provided high quality of evidence that bracing can decrease likelihood of progression and need for operative treatment. Very low evidence exists regarding bracing over 40^ο and adult degenerative scoliosis. Initial in-brace correction and compliance seem to be the most important predictive factors for successful treatment outcome. However, the amount of correction and adherence to wearing hours have not been established yet. Moderate evidence suggests that thoracic and double curves, and curves over 30^ο at an early growth stage have more risk for failure. High and low body mass index scores are also associated with low successful rates. CAD/CAM braces have shown better initial correction and are more comfortable than conventional plaster cast braces. For a curve at high risk of progression, rigid and day-time braces are significantly more effective than soft or night-time braces. No safe conclusion on effectiveness can be drawn while comparing symmetrical and asymmetrical brace designs. The addition of physiotherapeutic scoliosis-specific exercises in brace treatment can provide better outcomes and is recommended, when possible. Despite the growing evidence for brace effectiveness, there is still an imperative need for future high methodological quality studies to be conducted.

[Claims and realities of brace treatment : Primary correction of scoliosis in children and adolescents]

BACKGROUND

It is understood that an effective brace therapy requires a primary curve angle reduction of 50% after administering the first orthotic brace.

OBJECTIVES

The aim of the study was to determine the efficacy of conservative brace therapy for scoliosis with a curve angle above 20° and to determine possible influencing factors.

MATERIALS AND METHODS

The current study included a cohort of 110 scoliosis patients with conservative brace therapy. The development of the scoliotic curve during brace therapy was documented for an average of 40 months. Influencing factors such as the initial Risser sign, age at the start of treatment, gender, curve patterns and body mass index were analyzed.

RESULTS

The collective consisted of 88 patients with idiopathic and 22 with neuromuscular spinal deformities. At the beginning of the brace therapy, the average age was 12.2 ± 2.8 years with a mean scoliosis curve angle of 30.4° ± 12.5°. The primary brace reduced the scoliotic curve by 31% to 20.9°. In children and adolescents with lower maturity status, the success of the brace therapy was greater than in patients with a higher Risser sign. In addition, children with obesity had less success during brace therapy than normal- or underweight children.

CONCLUSIONS

The initial curvature correction of 50% required for effective brace therapy could only be achieved in one third of the patients. On average, the correction was 31%.

Evaluation of Predictors and Outcomes of Bracing with Emphasis on the Immediate Effects of in-Brace Correction in Adolescent Idiopathic Scoliosis

Background

Adolescent idiopathic scoliosis (AIS) is defined as a lateral curvature of the spine of unknown etiology with a Cobb angle of greater than 10 degrees with vertebral rotation. Bracing, specifically with a rigid thoracolumbosacral orthosis (TLSO), decreases the risk of curve progression to over 50 degrees, the threshold for surgical intervention. Some authors have suggested that 30-50% in-brace correction of the Cobb angles is required to prevent significant curve progression. The purpose of the study is to evaluate the current bracing protocol at the University of Iowa as a quality control exercise for the treatment team.

Methods

AIS patients (n = 61; 8 male, 53 female) who received a Rosenberger TLSO at the University of Iowa Department of Orthopaedics and Rehabilitation from 2016-2017 were included in the study. Inclusion criteria include presence of pre-brace and in-brace x-rays within 3 months of initiating brace treatment. Patients with other diagnoses were excluded. Radiographic indicators of brace effectiveness, such as the Cobb angle, were measured.

Results

The in-brace x-rays of 46 (76%) patients showed less than 30% correction. Minimal changes from the pre- to in-brace x-ray were observed in other radiographic measures.

Conclusions

Results indicate that if the 30-50% correction recommended by the literature is valid, then modifications to the process of measuring, fabricating or modifying our current TLSO's for AIS are warranted.Level of evidence: III.

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.

Obesity in Pediatric Trauma

Obese children with high-energy injuries present with more severe injuries, more extremity injuries, and higher Injury Severity Scores. They are at increased risk for complications, prolonged ventilation, and ICU stay and have increased mortality. Obesity is associated with altered bone mass accrual and higher fracture rates. Obese patients have a higher risk of loss of reduction of forearm fractures, more severe supracondylar fractures, and a higher likelihood of lateral condyle fractures. Obese patients are more likely to have complications with femur fractures and have higher rates of foot and ankle fracture.

The radiographic parameter risk factors of rapid curve progression in Lenke 5 and 6 adolescent idiopathic scoliosis: A retrospective study

Various parameters related to growth and maturity have been shown to be risk factors for scoliosis curve progression. We previously identified correlations between curve progression and radiographic parameters in clinical practice, but there is a lack of research.The aim of this study was to investigate and identify the radiographic parameters that are risk factors for rapid curve progression in Lenke 5 or 6 adolescent idiopathic scoliosis (AIS).A retrospective review of patients who were prospectively enrolled at the initiation of brace wear and followed through completion of bracing or surgery was performed. The inclusion criteria were as follows: a Lenke type 5 or 6 classification, Risser sign grade 0 or 1 at the initial outpatient examination, a follow-up period of 6 months including a minimum of 4 follow-ups, At each visit, the whole spine x-ray was completed, the following data were measured and collected: angle of the lumbar curve (LC), rotation of the apical vertebra (RAV) in the LC, deviation of the apical vertebra (DAV) in the lumbar curve, clavicle angle, L5 tilt angle (TA), body mass index, flexibility of the LC (FLC), and peak angle velocity (PAV). A binary logistic regression analysis was used to assess the contribution of each variable to PAV onset. The touch types for the determination of the lowest instrumented vertebra (LIV) were compared at both the PAV and final follow-up.Thirty-six AIS patients were recruited. The binary logistic regression model indicated that the following variable values significantly contributed to a high risk of PAV occurrence: LC ≥30° (OR = 6.153, 95%CI = 1.683-22.488, P = .006), RAV ≥III (OR = 15.484, 95%CI = 4.535-52.865, P <.001), DAV ≥40 mm (OR = 8.599, 95%CI = 2.483-29.784, P <.001), and TA ≥10° (OR = 2.223, 95%CI = 3.094-27.563, P <.001). The touch types for LIV determination changed in 12 of 36 patients, with at least 1 segment added as the LIV between the PAV and the final visit.LC ≥30°, RAV ≥III, DAV ≥40 mm, and L5 TA≥10° were radiographic parameters associated with an increased risk of curve progression in Lenke 5 and 6 AIS. The orthopedic surgery performed at the PAV is the ideal timing, and it will preserve 1 active segment than later surgery.Level of evidence was 4.

Overweight is not predictive of bracing failure in adolescent idiopathic scoliosis: results from a retrospective cohort study

PURPOSE

Overweight was found to be a negative predictor of brace effectiveness for adolescent idiopathic scoliosis (AIS), with a threefold higher risk of progression than in normal weight patients. The aim of this study is to investigate overweight, as a predictor of brace results in AIS patients.

METHODS

Design: retrospective cohort study.

POPULATION

351 AIS patients (306 females), mean age 12.9 ± 1.4, mean Cobb 35.6 ± 11.4°, mean ATR 11 ± 4.3°, BMI 19.7 ± 3, median Risser: 2.

INCLUSION CRITERIA

no previous treatment, full-time prescription of brace at first visit (18-23 h per day), scoliosis physiotherapeutic exercise according to the SEAS protocol associated.

OUTCOME

improved, progressed, and stable according to the 5° Cobb agreed threshold.

STATISTICS

a stepwise linear regression was used to look for the effect of BMI as a predictor of result. A Chi-square test and logistic regression were used for the overweight category (BMI ≥ 85th percentile). Control for possible confounders was applied.

RESULTS

BMI is poorly correlated with final results. Confounders' adjustment did not change the correlation, and the predictive model explained about 10% of the result. Brace results were not statistically different in overweight and normal weight: 44 vs 52% improved, 52 vs 41% stable, and 3 vs 7% worsened, respectively.

DISCUSSION

Brace results were similar in overweight and normal weight subjects. These findings subvert the previous results and disprove the role of overweight as a negative predictor. Treatment management, brace type and effectiveness may play a major role in reducing the risks of scoliosis progression.

Low body mass index can be predictive of bracing failure in patients with adolescent idiopathic scoliosis: a retrospective study

PURPOSES

To determine the relationship between low body mass index (BMI) and the outcome of brace treatment in patients with adolescent idiopathic scoliosis (AIS).

METHODS

350 braced female AIS patients were included in this study. The baseline characteristics of the patient were recorded at their first visit, including age, Risser sign, digital skeletal age, BMI, curve pattern, and curve magnitude. Underweight was defined as lower than the 5th percentile of the sex- and age-specific BMI. The treatment was considered as a failure if the curve progressed more than 5°, or if patients underwent surgery. According to the final outcome of brace treatment, the cohort was divided into the success group and the failure group. A logistic regression model was created to determine the independent predictors of the bracing outcome.

RESULTS

24.5% (86/350) of the patients were identified as underweight at their initial visit, which was significantly higher than the rate of 13.1% (46/350) at the final follow-up (p < 0.001). At the initial visit of the patients, the rate of underweight was 17.6% (45/255) in the success group, which was significantly lower than the rate of 43.1% (41/95) in the failure group (p < 0.001). Logistic regression analysis showed that low BMI was significantly associated with bracing failure (p < 0.001).

CONCLUSION

The low BMI could be predictive of bracing failure in AIS patients, which should be taken into account when surgeons prescribe brace treatment to such patients.