Curve Progression in Adolescent Idiopathic Scoliosis With a Minimum of 2 Years' Follow-up After Completed Brace Weaning With Reference to the SRS Standardized Criteria

Discontinuation of brace treatment in adolescent idiopathic scoliosis (AIS): a scoping review

PURPOSE

Brace treatment for adolescent idiopathic scoliosis (AIS) is usually prescribed for 20-40° curves in patients with growth potential. The aim is to reduce the risk of curve progression during growth and to avoid the curve reaching a surgical threshold. Having as small a curve as possible at skeletal maturity will reduce the risk of curve progression during adult life. While evidence exists for brace treatment in AIS, there is disagreement on how and when to discontinue bracing. The purpose of this review was to investigate what criteria have been reported for initiating brace cessation and published weaning protocols and to look at estimates of the number of patients that may progress > 5 degrees after the end of growth.

METHODS

This scoping review summarizes existing knowledge on the best time to stop bracing in AIS patients, how to "wean," and what happens to spinal curves after bracing. Searches were carried out through MEDLINE, EMBASE, and PsycINFO in April 2022. A total of 1936 articles were reduced to 43 by 3 reviewers. Full papers were obtained, and data were extracted.

RESULTS

Weaning was most commonly determined by Risser 4 (girls) and 5 (boys). Other requirements included 2 years post-menarche and no growth in standing/sitting height for 6 months. Skeletal maturity assessed from hand and wrist radiographs, e.g., Sanders' stage; distal radius and ulnar physes, could determine the optimal weaning time to minimize curve progression. Complete discontinuation was the most common option at skeletal maturity; variations on weaning protocols involved gradual reduction of bracing over 6-12 months. Curve progression after weaning is common. The 12 studies reporting early curve progression after brace weaning found a mean Cobb angle progression of 3.8° (n = 1655). From the seven studies reporting early curve progression by > 5 degrees, there were 236/700 (34%) patients. There is limited information on risk factors to predict early curve progression after finishing brace treatment with larger curves, especially those over 40 degrees possibly having more chance of progression.

CONCLUSION

Curve progression after bracing cessation is a negative outcome for patients who have tolerated bracing for several years, especially if surgery is required. The literature shows that when to start brace cessation and weaning protocols vary. Approximately 34% of patients progressed by more than 5 degrees at 2-4 years after brace cessation or weaning. Larger curves seem more likely to progress. More research is needed to evaluate the risk factors for curve progression after brace treatment, defining the best time to stop bracing based on the lowest risk of curve progression and whether there is any benefit to weaning.

Curve Progression and Clinical Outcomes in Pregnant Females with Adolescent Idiopathic Scoliosis: A Systematic Review and Meta-Analysis

BACKGROUND

Prior reviews investigating the impact of pregnancy on adolescent idiopathic scoliosis (AIS) have reached different conclusions and a meta-analysis of curve progression among pregnant females with AIS and its effects on clinical outcomes has not previously been performed.

METHODS

A comprehensive search of major bibliographic databases (PubMed, Embase, and Scopus) was conducted for articles pertaining to spinal curve progression during pregnancy among patients with AIS. Patient demographics, scoliotic curve outcomes, and patient-reported quality of life measures were extracted.

RESULTS

Ten studies, including 857 patients with a mean age of 28.7 years, were included. Before pregnancy, 42.1% had undergone spinal fusion and 59.0% had a thoracic curve. Based on prepregnancy and postpregnancy radiographs, the curve increased from 33.9°-38.5°, and meta-analysis revealed a curve progression of 3.6° (range = -5.85 to 1.25, P = 0.003), primarily arising from loss of correction in the unfused group (Unfused = -5.0, P = 0.040; Fused = -3.0, P = 0.070). At the same time, 45.9% patients reported increased low back pain and many reported a negative body self-image and limitations in sexual function. However, 5 studies noted that pregnancy and number of pregnancies were not associated with curve progression, and multiple studies identified similar quality of life-related changes in non-pregnant patients with AIS.

CONCLUSIONS

Among unfused pregnant females with AIS, the spinal curvature increased significantly by 5.0° from before to after pregnancy. However, these changes may be independent of pregnancy status and occur with time. Such curve progression can contribute to a negative body self-image, low back pain, and functional limitations irrespective of pregnancy state.

Immediate vs Gradual Brace Weaning Protocols in Adolescent Idiopathic Scoliosis: A Randomized Clinical Trial

Importance

Lack of evidence and consensus for brace weaning protocol in adolescent idiopathic scoliosis (AIS) results in clinicians prescribing gradual weaning in the hope of avoiding curve deterioration after weaning. However, gradual weaning contributes to prolonged brace wear, which can affect spinal stiffness and health-related quality of life (HRQoL).

Objective

To determine whether gradual weaning results in better curve magnitude and truncal balance maintenance after brace weaning vs immediate brace removal for patients with AIS.

Design, Setting, and Participants

This was an open-labeled randomized clinical trial commenced in April 2017 with 24-month follow-up completed in January 2023. Outcome assessors were masked to weaning protocol assigned. The study took place at a territory-wide tertiary scoliosis clinic serving the largest number of referrals in the local population. Patients with AIS ready to wean off of brace wear were eligible (402 were screened; 33 were excluded [15 for <18 hours/day of brace-wear compliance before weaning, 11 were treated with Milwaukee brace, and 7 declined to participate]; and 369 were included), and those who were treated with a custom molded thoracolumbosacral orthosis and had reached skeletal maturity were consecutively recruited.

Interventions

Patients were randomized to gradual weaning protocol (n = 176) with an additional 6 months of nighttime wear before completely stopping or immediate weaning protocol (n = 193) with immediate brace removal at recruitment.

Main Outcomes and Measures

Changes in major curve Cobb angle and truncal balance from the time of weaning to 6-month, 12-month, and 24-month follow-up. HRQoL was also assessed using the refined Scoliosis Research Society 22-item and EuroQol 5-dimension questionnaires.

Results

A total of 369 patients (mean [SD] age, 14.9 [1.1] years; 304 [83.4%] girls) were randomized with 284 (77.0%) completing 24-month longitudinal follow-up. Immediate and gradual weaning groups had no significant differences in change of major Cobb angle at postweaning 6-month (difference, -0.6°; 95% CI, -1.4 to 0.2; P = .17), 12-month (difference, -0.3°; 95% CI, -1.2 to 0.6; P = .47), and 24-month (difference, -0.3°; 95% CI, -1.2 to 0.7; P = .60) follow-up. The number of curve progression, nonprogression, and rebound cases were comparable (χ22 = 2.123; P = .35). Postweaning changes in truncal balance and HRQoL demonstrated no significant differences between groups.

Conclusions

Gradual weaning did not demonstrate superiority to immediate weaning with predefined criteria of Cobb angle and truncal balance maintenance and HRQoL after brace weaning. Gradual and immediate weaning achieved very similar maintenance of brace outcomes in AIS. We therefore recommend the consideration of immediate brace weaning, which aims to benefit patients with earlier time for increased exercises and activity level.

Trial Registration

ClinicalTrials.gov Identifier: NCT03329716.

Deep learning-based identification of spine growth potential on EOS radiographs

OBJECTIVES

To develop an automatic computer-based method that can help clinicians in assessing spine growth potential based on EOS radiographs.

METHODS

We developed a deep learning-based (DL) algorithm that can mimic the human judgment process to automatically determine spine growth potential and the Risser sign based on full-length spine EOS radiographs. A total of 3383 EOS cases were collected and used for the training and test of the algorithm. Subsequently, the completed DL algorithm underwent clinical validation on an additional 440 cases and was compared to the evaluations of four clinicians.

RESULTS

Regarding the Risser sign, the weighted kappa value of our DL algorithm was 0.933, while that of the four clinicians ranged from 0.909 to 0.930. In the assessment of spine growth potential, the kappa value of our DL algorithm was 0.944, while the kappa values of the four clinicians were 0.916, 0.934, 0.911, and 0.920, respectively. Furthermore, our DL algorithm obtained a slightly higher accuracy (0.973) and Youden index (0.952) compared to the best values achieved by the four clinicians. In addition, the speed of our DL algorithm was 15.2 ± 0.3 s/40 cases, much faster than the inference speeds of the clinicians, ranging from 177.2 ± 28.0 s/40 cases to 241.2 ± 64.1 s/40 cases.

CONCLUSIONS

Our algorithm demonstrated comparable or even better performance compared to clinicians in assessing spine growth potential. This stable, efficient, and convenient algorithm seems to be a promising approach to assist doctors in clinical practice and deserves further study.

CLINICAL RELEVANCE STATEMENT

This method has the ability to quickly ascertain the spine growth potential based on EOS radiographs, and it holds promise to provide assistance to busy doctors in certain clinical scenarios.

KEY POINTS

• In the clinic, there is no available computer-based method that can automatically assess spine growth potential. • We developed a deep learning-based method that could automatically ascertain spine growth potential. • Compared with the results of the clinicians, our algorithm got comparable results.

Differences in spine growth potential for Sanders maturation stages 7A and 7B have implications for treatment of idiopathic scoliosis

PURPOSE

This study aimed to clarify the differences in spine and total body height growth and curve progression between Sanders maturation stage (SMS) 7A and 7B in patients with adolescent idiopathic scoliosis (AIS).

METHODS

This retrospective case-control study involving patients with AIS at SMS 7 evaluated the differential gains in the spine (T1-S1) and total body height and curve progression between SMS 7A and 7B. A validated formula was used to calculate the corrected height, accounting for height loss due to scoliosis. A multivariable non-linear and logistic regression model was applied to assess the distinct growth and curve progression patterns between the SMS 7 subtypes, adjusting for potential confounders.

RESULTS

A total of 231 AIS patients (83% girls, mean age 13.9 ± 1.2 years) were included, with follow-up averaging 3.0 years. Patients at SMS 7A exhibited larger gains in spine height (9.9 mm vs. 6.3 mm) and total body height (19.8 mm vs. 13.4 mm) compared with SMS 7B. These findings remained consistent even after adjustments for curve magnitude. Non-linear regression models showed continued spine and total body height increases plateauing after 2 years, significantly greater in SMS 7A. More SMS 7A patients had curve progression over 10°, with an adjusted odds ratio of 3.31.

CONCLUSION

This study revealed that patients staged SMS 7A exhibited more spine and total body growth and a greater incidence of substantial curve progression than those at 7B. These findings imply that delaying brace discontinuation until reaching 7B could be beneficial, particularly for those with larger curves.

LEVEL OF EVIDENCE

Level III (Case-control study).

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.

Could trochanteric pelvic stabilization be removed from the adolescent idiopathic scoliosis brace? A prospective pilot study

BACKGROUND

Idiopathic scoliosis is the most common musculoskeletal deformity in children. There is a dose-response relationship between compliance and improvement in scoliosis. The literature revealed that esthetic considerations have negative consequences on the quality of life (QOL) of patients and consequently on wearing time of the brace. To minimize esthetic problems and then increase QOL and wearing time, we proposed a new relay brace named "corset Collerette" without a pelvic-trochanteric base.

METHODS

A prospective cohort study was conducted in the rehabilitation department of Bordeaux University Hospital. Patients consulting for adolescent idiopathic scoliosis were registered in a prospective hospital database. The patients expressing unwillingness to wear the usual brace or who had decreased compliance were offered the corset Collerette and were included in a 3-month follow-up. Outcome measures assessed at baseline and at 3 months were Scoliosis Research Society Outcomes Questionnaire (SRS-22) and Brace Questionnaire scales and wearing time. Cobb's angle evolution since the start of bracing was also collected. The primary end point was the QOL assed by the SRS-22 scale at 3 months of follow-up.

RESULTS

The first 38 patients agreeing to wear the corset Collerette were included in the study. The QOL assessed by the SRS-22 was significantly improved with the corset Collerette ( p < 0.05). There was no significant increase in wearing time and thoracic Cobb's angles between baseline and follow-up ( p > 0.05).

CONCLUSION

The switch to the corset Collerette allowed an improvement in the QOL of the patients and avoid a decrease in compliance with wearing the brace and maintain the same in-brace Cobb's angles.

Early brace treatment for idiopathic scoliosis may change the paradigm to improve curves

PURPOSE

This study evaluated whether early brace treatment of curves < 25° decreased the prevalence of curve progression and surgery.

METHODS

In a retrospective review, patients with idiopathic scoliosis Risser stages 0 to 2 braced at < 25° were followed until brace discontinuation, skeletal maturity, or surgery. Patients with predominantly primary thoracolumbar/lumbar curves were prescribed nighttime braces (NTB) and thoracic curves were prescribed fulltime braces (FTB). Comparisons were made for TLSO type (NTB vs. FTB) and triradiate cartilage (TRC) status (open vs. closed) at brace prescription.

RESULTS

283 patients were included, 81% who were Risser stage 0 with curves averaging 21.8° ± 2.1° at brace prescription. The average curve change was 2.4° ± 11.2°. Curves improved ≥ 6° in 23% of patients. Patients who were not skeletally mature at brace discontinuation (n = 39) had lower Cobb angles (16.7° vs. 23.9°, p < 0.001), better curve improvement (- 4.7° vs. 2.1°, p < 0.001), and were braced for a shorter period of time (1.8 years vs. 2.3 years, p = 0.011) than those who were skeletally mature at brace discontinuation (n = 239). Only 7% of patients in NTB and 8% of patients in FTB with open TRC required surgery. The numbers needed to treat to prevent surgery in patients in FTB with open TRC was calculated to be 4.

CONCLUSION

Early brace treatment (Cobb < 25° and open TRC) may not only reduce curve progression and the need for surgical treatment but may also result in curve improvement, thus challenging the paradigm that the goal of bracing is merely to stop curve progression.

LEVEL OF EVIDENCE

3-retrospective cohort study.

Alternate In-Brace and Out-of-Brace Radiographs Are Recommended to Assess Brace Fitting and Curve Progression With Adolescent Idiopathic Scoliosis Follow-Up

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine the prevalence of missed curve progression in patients with adolescent idiopathic scoliosis (AIS) undergoing brace treatment with only in-brace follow-up radiographs, and to provide recommendations on when in-brace and out-of-brace should be obtained during follow-up.

METHODS

133 patients who had documented clinically significant curve progression during brace treatment or only when an out-of-brace radiograph were studied. Of these, 95 patients (71.4%) had curve progression noted on in-brace radiographs while 38 patients (28.6%) showed curve progression only after brace removal. We analyzed differences in age, sex, curve types, Risser stage, months after menarche, standing out-of-brace Cobb angle, correction rate, and flexibility rate between the groups. Multivariate logistic regression was performed to determine factors contributing to curve progression missed during brace treatment.

RESULTS

There were no differences in initial Cobb angle between out-of-brace and in-brace deterioration groups. However, the correction rate was higher (32.7% vs 25.0%; P = .004) in the in-brace deterioration group as compared to the out-of-brace deterioration group. A lower correction rate was more likely to result in out-of-brace deterioration (OR 0.970; P = .019). For thoracic curves, higher flexibility in the curves was more likely to result in out-of-brace deterioration (OR 1.055; P = .045). For double/triple curves, patients with in-brace deterioration had higher correction rate (OR 0.944; P = .034).

CONCLUSIONS

Patients may develop curve progression despite good correction on in-brace radiographs. Those with higher flexibility and suboptimal brace fitting are at-risk. In-brace and out-of-brace radiographs should be taken alternately for brace treatment follow-up.

The natural history of curve behavior after brace removal in adolescent idiopathic scoliosis: a literature review

PURPOSE

Brace treatment is the most common nonoperative treatment to prevent curve progression in adolescent idiopathic scoliosis (AIS). The goal of this review and analysis is to characterize curve behavior after completion of brace treatment and to identify factors that may facilitate the estimation of long-term curve progression.

METHOD

A review of the English language literature was completed using the MEDLINE (PUBMED) database of publications after 1990 until September 2020. Studies were included if they detailed a minimum of 1 year post-brace removal follow-up of AIS patients. Data retrieved from the articles included Cobb angle measurements of the major curves at "in-brace," weaning, and follow-up visit(s) for all patients described and for subset populations.

RESULTS

From 75 articles, 18 relevant studies describing a follow-up period of 1-25 years following brace removal were included in the analyses. The reviewed literature demonstrates that curves continue to progress after brace treatment is completed with three main phases of progression: (i) immediate (upon brace removal) where a mean curve progression of 7° occurs; (ii) short term (within five years of brace removal) where a relatively high progression rate is evident (0.8°/year); and (iii) long term (more than five years after brace removal) where the progression rate slows (0.2°/year). The magnitude and rate of curve progression is mainly dependent on the degree of curve at weaning as curves weaned at < 25° progress substantially less than curves weaned at ≥ 25° at 25 years.

CONCLUSION

Curves continue to progress after brace removal and the rate and magnitude of progression are associated with the curve size at weaning, with larger curves typically exhibiting more rapid and severe progression. This analysis provides physicians and patients the ability to estimate long-term curve size based on the curve size at the time of weaning.

LEVEL OF EVIDENCE

IV.

Curve type, flexibility, correction, and rotation are predictors of curve progression in patients with adolescent idiopathic scoliosis undergoing conservative treatment : a systematic review

AIMS

The aim of this study was to review the current evidence surrounding curve type and morphology on curve progression risk in adolescent idiopathic scoliosis (AIS).

METHODS

A comprehensive search was conducted by two independent reviewers on PubMed, Embase, Medline, and Web of Science to obtain all published information on morphological predictors of AIS progression. Search items included 'adolescent idiopathic scoliosis', 'progression', and 'imaging'. The inclusion and exclusion criteria were carefully defined. Risk of bias of studies was assessed with the Quality in Prognostic Studies tool, and level of evidence for each predictor was rated with the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. In all, 6,286 publications were identified with 3,598 being subjected to secondary scrutiny. Ultimately, 26 publications (25 datasets) were included in this review.

RESULTS

For unbraced patients, high and moderate evidence was found for Cobb angle and curve type as predictors, respectively. Initial Cobb angle > 25° and thoracic curves were predictive of curve progression. For braced patients, flexibility < 28% and limited in-brace correction were factors predictive of progression with high and moderate evidence, respectively. Thoracic curves, high apical vertebral rotation, large rib vertebra angle difference, small rib vertebra angle on the convex side, and low pelvic tilt had weak evidence as predictors of curve progression.

CONCLUSION

For curve progression, strong and consistent evidence is found for Cobb angle, curve type, flexibility, and correction rate. Cobb angle > 25° and flexibility < 28% are found to be important thresholds to guide clinical prognostication. Despite the low evidence, apical vertebral rotation, rib morphology, and pelvic tilt may be promising factors. Cite this article: Bone Joint J 2022;104-B(4):424-432.

Controversies with nonoperative management for adolescent idiopathic scoliosis: Study from the APSS Scoliosis Focus Group

PURPOSE

To determine consensus among Asia-Pacific surgeons regarding nonoperative management for adolescent idiopathic scoliosis (AIS).

METHODS

An online REDCap questionnaire was circulated to surgeons in the Asia-Pacific region during the period of July 2019 to September 2019 to inquire about various components of nonoperative treatment for AIS. Aspects under study included access to screening, when MRIs were obtained, quality-of-life assessments used, role of scoliosis-specific exercises, bracing criteria, type of brace used, maturity parameters used, brace wear regimen, follow-up criteria, and how braces were weaned. Comparisons were made between middle-high income and low-income countries, and experience with nonoperative treatment.

RESULTS

A total of 103 responses were collected. About half (52.4%) of the responders had scoliosis screening programs and were particularly situated in middle-high income countries. Up to 34% obtained MRIs for all cases, while most would obtain MRIs for neurological problems. The brace criteria were highly variable and was usually based on menarche status (74.7%), age (59%), and Risser staging (92.8%). Up to 52.4% of surgeons elected to brace patients with large curves before offering surgery. Only 28% of responders utilized CAD-CAM techniques for brace fabrication and most (76.8%) still utilized negative molds. There were no standardized criteria for brace weaning.

CONCLUSION

There are highly variable practices related to nonoperative treatment for AIS and may be related to availability of resources in certain countries. Relative consensus was achieved for when MRI should be obtained and an acceptable brace compliance should be more than 16 hours a day.

Sanders stage 7b: Using the appearance of the ulnar physis improves decision-making for brace weaning in patients with adolescent idiopathic scoliosis

Aims

The aim of this study was to investigate whether including the stages of ulnar physeal closure in Sanders stage 7 aids in a more accurate assessment for brace weaning in patients with adolescent idiopathic scoliosis (AIS).

Methods

This was a retrospective analysis of patients who were weaned from their brace and reviewed between June 2016 and December 2018. Patients who weaned from their brace at Risser stage ≥ 4, had static standing height and arm span for at least six months, and were ≥ two years post-menarche were included. Skeletal maturity at weaning was assessed using Sanders staging with stage 7 subclassified into 7a, in which all phalangeal physes are fused and only the distal radial physis is open, with narrowing of the medial physeal plate of the distal ulna, and 7b, in which fusion of > 50% of the medial growth plate of distal ulna exists, as well as the distal radius and ulna (DRU) classification, an established skeletal maturity index which assesses skeletal maturation using finer stages of the distal radial and ulnar physes, from open to complete fusion. The grade of maturity at the time of weaning and any progression of the curve were analyzed using Fisher’s exact test, with Cramer’s V, and Goodman and Kruskal’s tau.

Results

We studied a total of 179 patients with AIS, of whom 149 (83.2%) were female. Their mean age was 14.8 years (SD 1.1) and the mean Cobb angle was 34.6° (SD 7.7°) at the time of weaning. The mean follow-up was 3.4 years (SD 1.8). At six months after weaning, the rates of progression of the curve for patients weaning at Sanders stage 7a and 7b were 11.4% and 0%, respectively for those with curves of < 40°. Similarly, the rates of progression of the curve for those being weaned at ulnar grade 7 and 8 using the DRU classification were 13.5% and 0%, respectively. The use of Sanders stages 6, 7a, 7b, and 8 for the assessment of maturity at the time of weaning were strongly and significantly associated (Cramer’s V 0.326; p = 0.016) with whether the curve progressed at six months after weaning. Weaning at Sanders stage 7 with subclassification allowed 10.6% reduction of error in predicting the progression of the curve.

Conclusion

The use of Sanders stages 7a and 7b allows the accurate assessment of skeletal maturity for guiding brace weaning in patients with AIS. Weaning at Sanders stage 7b, or at ulnar grade 8 with the DRU classification, is more appropriate as the curve did not progress in any patient with a curve of < 40° immediately post-weaning. Thus, reaching full fusion in both distal radial and ulnar physes (as at Sanders stage 8) is not necessary and this allows weaning from a brace to be initiated about nine months earlier. Cite this article: Bone Joint J 2021;103-B(1):141–147.

Can we predict the behavior of the scoliotic curve after bracing in adolescent idiopathic scoliosis? Τhe prognostic value of apical vertebra rotation

PURPOSE

We aimed to recognize radiographic and clinical prognostic factors of scoliotic curve behaviour after bracing.

METHODS

Our prognostic study was based on the 25 years outcomes of a Boston braced AIS cohort between 1978 and 1993 that were previously reported. All patients were followed-up during bracing, at short term and 25 years post-bracing. We evaluated the impact of socio-demographic, clinical and radiological parameters on the loss of curve correction after bracing.

RESULTS

Seventy-seven patients were reevaluated at 25 years post-brace. The mean scoliotic curve was significantly increased after bracing until the 25 years follow-up (p < 0.001). The mean loss of curve correction between the end of bracing and long-term follow-up was independent on the curve type, apical vertebra, premenarcheal status at bracing, time and duration of bracing, Cobb angle before or after bracing. The mean apical vertebral rotation after bracing was significantly related to the loss of curve correction (Spearman ρ = 0.2, p = 0.049). Apical vertebral rotation (Perdriolle method) greater than 20° post-bracing had a three times higher chance of progression > 5° compared with lesser apical vertebral rotation (OR 3.071, CI 0.99-9.51). The rotation of the apical vertebra, type and magnitude of the scoliotic curve after bracing explained 27.4% of the variance in the loss of curve correction post-bracing (R square = 0.274, p < 0.001).

CONCLUSION

A scoliotic curve is expected to lose some correction after bracing. The apical vertebral rotation post-bracing mainly affected the long-term curve behaviour. Adolescents with apical vertebral rotation greater than 20° after bracing may need further attention.

LEVEL OF EVIDENCE

Prognostic study, Level II.

Evaluation of the efficiency of Boston brace on scoliotic curve control: A review of literature

Context: Bracing is one of the most important treatment approaches that have been utilized in patients with scoliosis. Boston brace used to manage a scoliotic curve especially in lumbar and thoracolumbar areas. Objective: The aim of this review was to evaluate the efficiency of Boston brace to control the progression of the curve based on the available literature. Methods: A search was carried out using the following databases including Scopus, ISI Web of knowledge, PubMed, Ebsco, and Embasco. The key words used for the search were Boston brace, Boston orthosis which were used in combination with scoliosis. Articles identified were screened based on titles and abstracts. The quality of the studies was evaluated using Black and Down tool. Data were summarized based on PICO style. Results: Based on the aforementioned key words, 18 papers were selected, in which 7 studies focused on efficiency of Boston brace, 3 papers focused on quality of life, 5 papers on finite element analysis and 3 papers on comparison of efficiency of Boston with other available braces. The quality of the selected studies varied between 14 and 21. Conclusion: The results of most of the studies support the efficiency of this brace to control the progression of scoliotic curve, especially for the curve between T6 and L2. The efficiency of this brace may be due to its rigid structure and also location and direction of the straps.

Intermediate-term annualized curve progression of adolescent idiopathic scoliosis curves measuring 40° or greater

STUDY DESIGN

Prospective cohort study.

OBJECTIVES

The objective of this study was to examine intermediate-term progression for a large series of patients with adolescent idiopathic scoliosis (AIS) with curves 40° or greater.

BACKGROUND

Curve progression in AIS has been well documented for smaller curves in adolescence up to skeletal maturity; however, the data on curve progression past 40° or into adulthood are limited. With many surgeons recommending surgical correction when patients reach this threshold, it is important to understand the radiographic progression of curves into adulthood.

METHODS

A database of all patients seen by a single surgeon from 1984 through 2018 with AIS curves progressing to at least 40° entered prospectively was utilized for this study. This included a total of 738 patients. Curve progression was analyzed overall and stratified by length of follow-up, curve location, and Risser stage at the time of presentation among other variables. Curve magnitude and Risser stage designations in this study were validated by performing a separate inter- and intrarater agreement study using four independent reviewers reading 50 patients' Cobb angle and Risser stage blinded in triplicate to examine the reliability of the study measurements.

RESULTS

Annualized curve progression (ACP) averaged 6.3 ± 10.4°. ACP varied with length of follow-up: patients with up to 1 year of follow-up had an average ACP of 11.5 ± 17.0°, while those with 1-2 years had 8.2 ± 8.8°, and 2-5 years had 3.7 ± 4.1°, tapering off further from there. Risser stage 0 or 1 was associated with the highest ACP as compared to Risser stage 2-3 or 4-5. Intraclass correlation (ICC) values for Cobb angle measurement and Risser stage designations from four raters measuring 50 patients' measures, blinded and in triplicate, were all > 0.80, signifying a high degree of reliability within and between readers.

CONCLUSIONS

Annualized curve progression for 40° and greater curves was not linear over time; it was greatest immediately after a curve reaches 40° and tapered off over the next decade. Immature Risser stage at presentation was strongly associated with increasing ACP at all time frames.

LEVEL OF EVIDENCE

Prognostic Level I.

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.

When Should We Wean Bracing for Adolescent Idiopathic Scoliosis?

BACKGROUND

Current brace weaning criteria for adolescents with idiopathic scoliosis (AIS) are not well defined. Risser Stage 4, ≥ 2 years since the onset of menarche, and no further increase in body height over 6 months are considered justifications for stopping bracing. However, despite adherence to such standards, curve progression still occurs in some patients, and so better criteria for brace discontinuation are needed.

QUESTIONS/PURPOSES

(1) Is no change in height measurements over 6 months and Risser Stage 4 sufficient for initiating brace weaning? (2) What is the association between larger curves (45°) at brace weaning and the progression risk? (3) Are a more advanced Risser stage, Sanders stage, or distal radius and ulna classification associated with a decreased risk of curve progression? (4) When should we wean patients with AIS off bracing to reduce the time for brace wear while limiting the risk of postweaning curve progression?

METHODS

All AIS patients who were weaned off their braces from June 2014 to March 2016 were prospectively recruited and followed up for at least 2 years after weaning. A total of 144 patients were recruited with mean followup of 36 ± 21 months. No patients were lost to followup. Patients were referred for brace weaning based on the following criteria: they were Risser Stage 4, did not grow in height in the past 6 months of followup, and were at least 2 years postmenarche. Skeletal maturity was assessed with Risser staging, Sanders staging, and the distal radius and ulna classification. Curve progression was determined as any > 5° increase in the Cobb angle between two measurements from any subsequent six monthly followup visits. All radiographic measurements were performed by spine surgeons independently as part of their routine consultations and without knowledge of this study. Statistical analyses included an intergroup comparison of patients with and without curve progression, binomial stepwise logistic regression analysis, odds ratios (ORs) with their 95% confidence intervals (CIs), and a risk-ratio calculation. A reasonable protective maturity stage would generate an OR < 1.

RESULTS

Among patients braced until they had no change in height for 6 months, were 2 years postmenarche for girls, and Risser Stage 4, 29% experienced curve progression after brace weaning. Large curves (≥ 45°) were associated with greater curve progression (OR, 5.0; 95% CI, 1.7-14.8; p = 0.002) as an independent risk factor. Patients weaned at Sanders Stage 7 (OR, 4.7; 95% CI, 2.1-10.7; p < 0.001), radius Grade 9 (OR, 3.9; 95% CI, 1.75-8.51; p = 0.001), and ulna Grade 7 (OR, 3.1; 95% CI, 1.27-7.38; p = 0.013) were more likely to experience curve progression. The earliest maturity indices with a reasonable protective association were Sanders Stage 8 (OR, 0.21; 95% CI, 0.09-0.48; p < 0.001), and radius Grade 10 (OR, 0.42; 95% CI, 0.19-0.97; p = 0.042) with ulna Grade 9 (no patients with curve progression).

CONCLUSION

Brace weaning indications using Risser staging are inadequate. Curve progression is expected in patients with large curves, irrespective of maturity status. Bone age measurement by either Sanders staging or the distal radius and ulna classification provides clearer guidelines for brace weaning, resulting in the least postweaning curve progression. Weaning in patients with Sanders Stage 8 and radius Grade 10/ulna Grade 9 provides the earliest and most protective timepoints for initiating brace weaning.

LEVEL OF EVIDENCE

Level II, prognostic study.

Predictors of a Non-home Discharge Destination Following Spinal Fusion for Adolescent Idiopathic Scoliosis (AIS)

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Analyze risk factors associated with a non-home discharge following spinal fusions in adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

Current evidence is limited with regard to which patient-level and provider/hospital-level factors predict a non-home discharge disposition following spinal fusions in AIS. Identifying these factors can allow providers to identify which patients would ultimately require facility care and can be discharged early to these facilities to reduce hospital costs.

METHODS

The 2012 to 2016 American College of Surgeons-National Surgical Quality Improvement Program Pediatric database was queried using Current Procedural Terminology codes for posterior spinal fusions (22800, 22802, and 22804) and anterior spinal fusions (22808, 22810, and 22812). Patients were categorized into those receiving a posterior-only fusion, anterior-only fusion, and combined anterior-posterior fusion. Only patients aged 10 to 18 undergoing corrective surgery for idiopathic scoliosis were included in the study.

RESULTS

Out of a total of 8452 patients-90 (1.1%) were discharged to a destination other than home (skilled-care facility, separate acute care unit, and/or rehabilitation unit). Following multivariate analysis, children with a body mass index of 20 to 30 (P = 0.002) or >30 (P = 0.003), structural pulmonary abnormality (P = 0.030), past history of childhood cancer (P = 0.018), an ASA grade >II (P<0.001), undergoing a revision surgery versus a primary surgery (P = 0.039), a length of stay >4 days (P<0.001), and the occurrence of a predischarge complication (P = 0.003) were independent predictors associated with a non-home discharge disposition.

CONCLUSION

In the current era of evolving health-care in which there is an increased focus toward decreasing costs, providers should consider utilizing these data to preoperatively identify patients who can be discharged to facility, and tailor an appropriate postoperative course of care aimed at expediting discharge processes to curb the financial burden of a prolonged length of stay.

LEVEL OF EVIDENCE

3.