A new risk classification rule for curve progression in adolescent idiopathic scoliosis

Subclassification of Sanders Maturation Stage 3 Demonstrates Differences in Spine and Total Height Velocity Between 3A and 3B in Patients With Idiopathic Scoliosis

STUDY DESIGN

A single-center retrospective case-control study.

OBJECTIVE

To compare the spine and total height velocity between Sanders maturation stage (SMS) 3A and 3B.

SUMMARY OF BACKGROUND DATA

Identifying SMS 3 is critical for treating growing children because it represents the early phase of rapid adolescent growth. However, there is limited literature available that clearly describes the growth differences between 3A and 3B.

MATERIALS AND METHODS

The current study included consecutive patients with idiopathic scoliosis staged SMS 3 from January 2012 to December 2021. T1-S1 spine height, total body height, and curve magnitude were measured at the initial and follow-up visits. In addition to the spine and total height velocity calculated per month, corrected height velocity was estimated for curve magnitude using a validated formula. Mann-Whitney U test was used to compare SMS 3A and 3B outcomes, followed by a multiple linear regression model to evaluate the association of the SMS subclassifications to growth velocity adjusted for confounding factors.

RESULTS

A total of 204 patients (66% girls, mean age: 12.3±1.3 y) met the inclusion criteria. Patients staged SMS 3A had higher spine height velocity (mm/month) in both girls (2.3 vs. 1.5, P <0.001) and boys (2.6 vs. 1.7, P <0.001), as well as total height velocity [mm/month; (5.8 vs. 4.3, P <0.001 for girls; 6.6 vs. 4.5, P <0.001 for boys]. Corrected velocity showed similar results with greater spine and total height velocity in SMS 3A. Multivariate analysis indicated a significant association of the SMS subclassification to the spine and total height velocity. The scoliosis curve progression was comparable between SMS 3A and 3B.

CONCLUSIONS

SMS 3A and 3B had differential growth velocity in the spine and total body height. These results indicate the importance of the SMS 3 subclassification for managing scoliosis treatment, including observation, bracing, and surgical interventions with fusion and growth modulation.

LEVEL OF EVIDENCE

Level III-case-control study.

Association between incorrect postures and curve magnitude of adolescent idiopathic scoliosis in china

BACKGROUND

Despite advancements in school scoliosis screening (SSS), there are still no effective indicators to estimate the severity of spinal curvature. We aim to investigate the association between incorrect postures and curve magnitude of adolescent idiopathic scoliosis (AIS) among Chinese adolescents.

METHODS

In this SSS program, we examined the incorrect posture, Adam's forward bending test (FBT) results, and angle of trunk rotation (ATR) in adolescents. Those with suspected scoliosis were referred for a standing anteroposterior whole-spine radiography as outpatients. The radiographic data of 426 students with lateral Cobb angles were collected from 2016 to 2022 and the associations were studied using logistic regression (LR) models and receiver operating characteristic (ROC) curves.

RESULTS

Univariate LR revealed that female gender [odds ratio (OR) = 2.92, 95% confidence interval (CI) 1.67-5.09, P < 0.001], age 16-19y (OR = 2.83, 95%CI 1.10-7.28, P = 0.031), right shoulder height (OR = 2.15, 95%CI 1.23-3.75, P = 0.007), right scapula tilt (OR = 2.03, 95%CI 1.18-3.50, P = 0.010), right rib hump (OR = 1.88, 95%CI 1.23-2.85, P = 0.003), right thoracic rotation ≥ 5° (OR = 2.14, 95%CI 1.43-3.20, P < 0.001), and left thoracolumbar kyphosis (OR = 3.79, 95%CI 1.06-13.56, P = 0.041) were all significantly associated with the severity of the curve magnitude. Multivariate LR showed that female gender [adjusted OR (AOR) = 3.23, 95%CI 1.81-5.73, P < 0.001], those aged 16-19y (AOR = 5.08, 95%CI 1.86-13.91, P = 0.002), and with a right rib hump (AOR = 1.72, 95%CI 1.11-2.64, P = 0.015) presented with a higher risk of severe curve magnitude than men, those aged 7-12y, and without a rib hump, respectively. ROC curves further proved that sex, age, shoulder-height difference, scapula tilt, flat back, rib hump, angle of thoracic rotation were the risk predictors for curve magnitude.

CONCLUSION

Incorrect posture and ATR, especially the right rib hump, were significantly associated with the curve magnitude of AIS. Early screening for incorrect postures and ATR could be an effective and economical strategy to predict the severity of AIS through SSS in Chinese adolescents.

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.

The Improvement of Trunk Muscle Endurance in Adolescents with Idiopathic Scoliosis Treated with ScoliBrace® and the ScoliBalance® Exercise Approach

The impact of scoliosis bracing combined with physiotherapeutic scoliosis-specific exercises (PSSE) on trunk muscle endurance in adolescents with idiopathic scoliosis is unknown. ScoliBrace®, a rigid, three-dimensional, over-corrective thoraco-lumbar-sacral orthosis (TLSO), and ScoliBalance®, a PSSE program, were used to treat adolescent idiopathic scoliosis (AIS) patients. A retrospective study of the trunk muscle endurance of 33 AIS patients who received ScoliBrace® and ScoliBalance® was conducted. The patients were treated with ScoliBrace® and an individualized ScoliBalance® program. Trunk extensor muscle endurance (TE) and abdominal muscle endurance (AE) tests were performed at initial assessment and then at averages of 6.6 and 24.4 weeks of treatment. The data were analyzed using the Wilcoxon signed-rank test, Stata version 15.1. The participants were aged 13.24 years (SD = 1.64) with a mean Cobb angle of 38.97° (SD = 9.49°). TE improved significantly (p < 0.001) at both short- and medium-term intervals using ScoliBalance® and ScoliBrace® in the AIS patients. AE also showed significant improvement between baseline and short-term follow-up, with non-significant improvement at medium-term follow-up. Overall, trunk muscle endurance showed improvement in the AIS patients using ScoliBrace® and ScoliBalance®. Future research is required to determine the individual and combined effects of each treatment. However, it seems likely that trunk muscle endurance will not deteriorate in AIS patients with this combined treatment.

Digital measurement and correlation analysis of coronal and sagittal anatomic parameters in the radiographs of adolescent patients with idiopathic scoliosis

OBJECTIVE

To use digital software to measure the morphologic and anatomic parameters of adolescent idiopathic scoliosis (AIS). Differences and correlations among different parameters were compared to provide an anatomic basis for the selection of treatment methods and preoperative evaluation of AIS.

METHODS

Spinal radiographs were taken from 300 boys and girls (age, 10-18 years) suffering from idiopathic scoliosis in four grade-A hospitals in Inner Mongolia. After screening, 120 cases with complete imaging data were assessed. Imaging data were transferred to a work station (Dr Wise™). The anatomic indices of the Cobb Angle, CVA, AVT, TS, CA, CPT, CSI, FPT, CCA, TK, LL, SS, PT, and PI were measured.

RESULTS

There were significant differences in AVT between different grades and types of scoliosis (F = 34.079, P = 0.000; χ² = 23.379, P = 0.000). AVT was a protective factor, and the smaller the AVT, the less severe was the scoliosis. Compared with adolescents with mild or moderate scoliosis, the Cobb angle of adolescents with severe scoliosis was negatively correlated with CCA, LL, and SS (r =  - 0.641, p < 0.05; r =  - 0.695, p < 0.01; r =  - 0.814, p < 0.01).

CONCLUSIONS

Some of the anatomic parameters in the coronal and sagittal planes of adolescents with idiopathic scoliosis were significantly different according to the severity and type of scoliosis. Significant correlations were found between more anatomic indices in adolescents with severe scoliosis than in adolescents suffering from mild or moderate scoliosis.

Deriving a Novel Score for the Stratification of Risk Progression in Early-onset Scoliosis: A Multicenter Initiative

STUDY DESIGN

This was a retrospective multicenter study.

OBJECTIVE

To develop a novel progression risk stratification scoring system for early-onset scoliosis.

SUMMARY OF BACKGROUND DATA

There is a lack of investigations into variables affecting the risk of curve progression in early-onset scoliosis, which prevents stratification. A novel risk score system is needed to help in progression risk estimation.

METHODS

A retrospective analysis was done at three centers, from 1995 to 2020. Scoliosis cases before the age of 10 years, were included. Medical identifier, date of birth, sex, primary diagnosis, curve type, date/modality of treatment, date of follow-up appointments, and Cobb angles, were collected. Five ranks were selected for stratification. Categories with the same ranks were discarded. Point scores started at 0, for the lowest risk, and ended at 4, for highest risk. Iterations of variable combinations were conducted and clinical relevance was determined by evaluating sensitivity, specificity, positive predictive value, and negative predictive value based on score ranges for low and high risk of progression.

RESULTS

A total of 476 (230 males, 246 females) early-onset scoliosis patients were collected. The average age at diagnosis was 4.8 years (SD±2.8 yr). The average follow-up duration was 9.3 years (SD±6.9 yr, range: 5 mo-38 yr). Appointments totaled 2911, giving 2182 observations for the analysis. Patient observations numbered: 800 (36.7%) ending in progression, 1265 (58.0%) for nonprogression, 117 (5.4%) for inadequate follow-up, and 368 (16.9%) for rapid progression. The risk scoring system contained four categories: etiology, age, curve magnitude, and curve type. Categorized point combinations totaled 755, giving 1975 iterations. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated to be 85.8%, 96.5%, 89.7%, and 95.1%, respectively.

CONCLUSION

A novel progression risk score for early-onset scoliosis was derived. The system can reliably differentiate between low and high-risk cases in clinical settings. Further validation in other regions may be important for verifying clinical relevance.

LEVEL OF EVIDENCE

Level 3.

Evaluation of the Radiographic Risk Factors of Postoperative Shoulder Imbalance in Adult Scoliosis

Objective

This study aimed to evaluate the radiographic risk factors of postoperative shoulder imbalance (PSI) after adult scoliosis (AS) correction surgery.

Methods

Seventy-nine patients with AS undergoing correction surgery at a single institution were reviewed. The mean follow-up was 28 months. Patients were divided into two groups based on their radiographic shoulder height (RSH): (1) the balanced group (RSH <10 mm) and (2) the unbalanced group (RSH ≥10 mm). The preoperative and postoperative Cobb angles of the proximal thoracic (PT), main thoracic (MT), thoracolumbar/lumbar (TL/L) and upper instrumented vertebra (UIV) were measured.

Results

No significant difference was found between the balanced and unbalanced groups when the UIV was T1–2, T3–4, or below T4. Univariate analysis indicated that the unbalanced group had significantly higher postoperative RSH, lower percentage PT correction, and greater percentage MT correction. The classification and regression tree analysis revealed that when the correction percentage of PT curve was more than 55.3%, 84.4% of patients acquired shoulder balance. However, when the correction percentage of PT curve was less than 55.3%, and the correction percentage of MT curve was more than 56%, 65.7% of the patients developed PSI.

Conclusions

In AS correction surgery, a lower percentage correction of the PT curve and greater percentage correction of the MT curve were independent radiographic risk factors of PSI, regardless of the UIV level. Sufficient PT correction is required to achieve postoperative shoulder balance in AS correction surgery when the MT curve is overcorrected.

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.

Diagnosis and conservative treatment of adolescent idiopathic scoliosis

Background: Adolescent idiopathic scoliosis (AIS) has a diagnosis rate of 3% to 5% per year, but the number of cases requiring surgical treatments is very small, accounting for only 0.17% to 1.75% of all AIS patients. Most patients with AIS are diagnosed, treated, and managed in outpatient clinics.Current Concepts: AIS is a disease that occurs more frequently, and progresses faster, in females than in males. Scoliosis deformity can occur due to various causes. To differentially diagnose AIS, it is necessary to perform careful physical examinations, investigate family history, and check for neurological, growth, and developmental abnormalities. Definitive diagnosis of AIS can be performed through radiographic imaging. In the case of atypical curvature and symptoms, examinations such as magnetic resonance imaging could be required in addition to radiographic imaging. Treatment of AIS patients in outpatient clinics can be performed through observation, exercise, and orthosis. The selection and application of treatment methods and the termination period of the treatments are complexly affected by the age at the time of diagnosis; pattern, location and size of the curve; and growth potential.Discussion and Conclusion: AIS is a disease in which good results can be obtained with conservative treatments such as exercise and orthosis, which is generally applied in an outpatient setting. To properly treat AIS, it is necessary to have an in-depth understanding of the characteristics of AIS, timing of treatment, and factors influencing treatment.

Scoliosis and Prognosis-a systematic review regarding patient-specific and radiological predictive factors for curve progression

INTRODUCTION

Idiopathic scoliosis, defined as a > 10° curvature of the spine in the frontal plane, is one of the most common spinal deformities. Age, initial curve magnitude and other parameters define whether a scoliotic deformity will progress or not. Still, their interactions and amounts of individual contribution are not fully elaborated and were the aim of this systematic review.

METHODS

A systematic literature search was conducted in the common databases using MESH terms, searching for predictive factors of curve progression in adolescent idiopathic scoliosis ("adolescent idiopathic scoliosis" OR "ais" OR "idiopathic scoliosis") AND ("predictive factors" OR "progression" OR "curve progression" OR "prediction" OR "prognosis"). The identified and analysed factors of each study were rated to design a top five scale of the most relevant factors.

RESULTS

Twenty-eight investigations with 8255 patients were identified by literature search. Patient-specific risk factors for curve progression from initial curve were age (at diagnosis < 13 years), family history, bone mineral status (< 110 mg/cm³ in quantitative CT) and height velocity (7-8 cm/year, peak 11.6 ± 1.4 years). Relevant radiological criteria indicating curve progression included skeletal maturity, marked by Risser stages (Risser < 1) or Sanders Maturity Scale (SMS < 5), the initial extent of the Cobb angle (> 25° progression) and curve location (thoracic single or double curve).

DISCUSSION

This systematic review summarised the current state of knowledge as the basis for creation of patient-specific algorithms regarding a risk calculation for a progressive scoliotic deformity. Curve magnitude is the most relevant predictive factor, followed by status of skeletal maturity and curve location.

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.

Follow-up schedule for initial recurrent hepatocellular carcinoma after ablation based on risk classification

Background

To date, no standard follow-up guidelines exist regarding patients receiving ablation for initial recurrent hepatocellular carcinoma (HCC). We aimed to explore whether intensive follow-up could benefit these patients.

Methods

We reviewed the clinical data of patients who received complete ablation for initial HCC recurrence after curative treatments in our institution from January 2005 to June 2017. Risk factors for second recurrence of HCC were identified by univariate and multivariate analyses. Patients were classified into low- and high-risk groups according to the outcome of the classification and regression model. The patients were further categorized into short- (< 3 months) and long-interval (3–6 months) follow-up subgroups based on their surveillance in the first 2 years after complete ablation for initial recurrence. The Kaplan-Meier method with log-rank test was performed to compare the overall survival (OS) based on follow-up intervals in each risk group. We also validated our results by stratifying patients into subgroups with different numbers of risk factors and comparing the OS between patients with different follow-up intervals.

Results

A total of 361 patients were enrolled. The risk factors for secondary recurrence included the Barcelona Clinic Liver Cancer (BCLC) stage at initial recurrence and first recurrence-free survival after curative treatments for primary HCC (p < 0.001 and p = 0.002). Two risk groups (low and high) were identified. In both the low- and high-risk groups, the OS of patients was not associated with intervals of follow-up (p = 0.29 and 0.49). No significant difference was found in the rates of BCLC 0/A stage, tumor location or curative treatments for the second recurrence by different follow-up intervals in each risk group (p = 0.34 and 0.87; p = 0.69 and 0.97). The same tendency was found in subgroups with 0/1/2 risk factors for secondary recurrence during validation.

Conclusion

The long-interval follow-up did not compromise the survival of patients with complete ablation for initial recurrent HCC.

An Overview of the Current State of Pediatric Scoliosis Management

Historically pediatric scoliosis represents a condition deeply rooted within the origins of orthopedic surgery. Today only a few subspecialized surgeons treat pediatric scoliosis patients. In severe cases surgery can hold progression of and correct pathologic spinal curvature. The goal of this article is to provide an overview of the current state of pediatric scoliosis management. It aims to increase the attention of general physicians and orthopedic surgeons to a niched but rather frequently encountered pediatric pathology to facilitate early recognition and diagnosis. A thorough research of literature was conducted to summarize the different scoliosis types, their etiology and presentation. Classification, normal human growth phases and curve progression risk have been further elaborated. Finally, current treatment options with their benefits, shortcomings and complications were laid out and discussed. Among the etiological groups a focus was put on idiopathic scoliosis, in particular adolescent idiopathic scoliosis as the most frequently encountered subtype.

Value of DNA methylation in predicting curve progression in patients with adolescent idiopathic scoliosis

BACKGROUND

There is considerable discordance in the curve progression of adolescent idiopathic scoliosis (AIS) patients between monozygotic (MZ) twins, indicating that nongenetic factors must be involved in the curve progression of AIS patients. Epigenetic processes may constitute one of these factors and have not yet been investigated in relation to curve progression in AIS patients.

METHODS

The genome and methylome of peripheral monocytes were compared between MZ twins discordant for curve progression. Sets of differentially methylated sites were validated using the MassARRAY platform of Sequenome on additional samples.

RESULTS

In the discovery study, we found evidence suggesting a lack of differences at the genome sequence level and the presence of epigenetic differences related to the curve progression of AIS patients. The top 4 differentially methylated CpG sites associated with curve severity were tested, and only site cg01374129 (CpG site located at chr8:122583383, Hg19) was confirmed in two replication cohorts. The methylation levels of site cg01374129 were significantly lower in the progression group than in the nonprogression group. Cox regression analysis demonstrated that hypo-methylation of site cg01374129 was an independent prognostic factor for curve severity. Site cg01374129 methylation as a marker achieved a sensitivity of 76.4% and a specificity of 85.6% in differentiating between samples from patients with and without curve progression (AUC = 0.827; 95% CI: 0.780 to 0.876).

CONCLUSION

Increased curvature is associated with decreased methylation at site cg01374129. Our results indicate that methylation of site cg01374129 may therefore serve as a promising biomarker in differing between patients with and without curve progression.

Specific exercises reduce the need for bracing in adolescents with idiopathic scoliosis: A practical clinical trial

BACKGROUND

In an ideal experimental setting, 2 randomized controlled trials recently showed the efficacy of physiotherapeutic scoliosis-specific exercises (PSSEs) for adolescents with idiopathic scoliosis (AIS). Now large observational studies are needed to check the generalizability of these results to everyday clinical life.

OBJECTIVE

To explore the effectiveness of PSSEs for avoiding bracing or progression of AIS in everyday clinics.

METHODS

This was a longitudinal comparative observational multicenter study, nested in a prospective database of outpatient tertiary referral clinics, including 327 consecutive patients. Inclusion criteria were AIS, age≥10 years old at first evaluation, Risser sign 0-2, and 11-20°Cobbangle. Exclusion criteria were consultations only and brace prescription at baseline. Groups performed PSSE according to the SEAS (Scientific Exercise Approach to Scoliosis) School, usual physiotherapy (UP) and no therapy (controls [CON]). End of treatment was medical discharge, Risser sign 3, or failure (defined by the need for bracing before the end of growth or Cobb angle>29°). The probability of failure was estimated by the risk ratio (RR) and 95% confidence interval (CI). The number needed to treat was estimated. Statistical analysis included intent-to-treat analysis, considering all participants (dropouts as failures), and efficacy analysis, considering only end-of-treatment participants. Propensity scores were used to reduce the potential effects of confounders related to the observational design.

RESULTS

We included 293 eligible subjects after propensity score matching (SEAS, n=145; UP, n=95; controls, n=53). The risk of success was increased 1.7-fold (P=0.007) and 1.5-fold (P=0.006) with SEAS versus controls in the efficacy and intent-to-treat analyses, respectively, and the number needed to treat for testing SEAS versus controls was 3.5 (95% CI 3.2-3.7) and 1.8 (95% CI 1.5-2.0), respectively. The success rate was higher with SEAS than UP in the efficacy analysis.

CONCLUSIONS

SEAS reduced the bracing rate in AIS and was more effective than UP. PSSEs are additional tools that can be included in the therapeutic toolbox for AIS treatment.

The Risk of Curve Progression and Surgery in African Americans With Adolescent Idiopathic Scoliosis

STUDY DESIGN

Retrospective clinical cohort study.

OBJECTIVE

To determine if certain risk factors (age, curve magnitude, skeletal maturity, gender, and curve pattern) traditionally associated with curve progression and surgical intervention in the general population apply equally to African Americans.

SUMMARY OF BACKGROUND DATA

Currently, information is limited on the role that a patient's race plays in the risk of curve progression of adolescent idiopathic scoliosis (AIS), and existing studies have conflicting results.

METHODS

Retrospective search of records identified patients who were African American, had been diagnosed with AIS, had a major curve Cobb angle of 10 degrees or more, and had at least two clinical visits with spinal radiographs at least 90 days apart to determine the risk factors for surgical treatment, and 2 years apart to determine the risk factors for curve progression. Patients with a medical condition likely to cause scoliosis were excluded.

RESULTS

Of 738 African American patients with AIS, 223 were assessed for surgical risk factors, and 72 were assessed for curve progression risk factors. Fifty-six (29.17%) had progression of the major coronal curve, and 38 (17.04%) underwent surgery. Age at presentation and curve magnitude at presentation were significant risk factors for surgical intervention. Curve magnitude at presentation was a significant risk factor for curve progression. No significant relationships were found for gender or curve type as they relate to surgical intervention or curve progression.

CONCLUSION

Age and curve magnitude at presentation were significantly associated with surgery, as is true in other scoliosis populations. Curve magnitude at presentation was associated with curve progression. In contrast to studies in other populations, however, no significant association was observed between curve progression and age at presentation, curve type, or gender, or between surgery and curve type or gender.

LEVEL OF EVIDENCE

Level III, prognostic cohort study.

Replication of Association Between 53 Single-Nucleotide Polymorphisms in a DNA-Based Diagnostic Test and AIS Progression in Chinese Han Population

STUDY DESIGN

A case-only study.

OBJECTIVE

The aim of this study was to evaluate the association of the 53 single-nucleotide polymorphisms (SNPs) in a prognostic test with curve progression in Chinese adolescent idiopathic scoliosis (AIS) patients.

SUMMARY OF BACKGROUND DATA

"ScoliScore" was the first diagnostic kit developed for curve progression of AIS in the white population. To date, there is still a paucity of validation of ScoliScore in Chinese Han population.

METHODS

A total of 670 AIS patients were included in the study, with 313 patients assigned to the nonprogression group and the other 357 patients assigned to the progression group. A panel of 53 SNPs encompassed in ScoliScore were genotyped using the PCR-based Invader assay. The allele frequencies were compared between AIS patients with progressive curve and those with nonprogressive curve.

RESULTS

SNP rs9945359 and rs17044552 are the only 2 SNPs that had significantly different allele frequencies between the 2 groups. Allele A of rs9945359 was significantly higher in the progression group than in the nonprogression group (25.7% vs 19.5%, P = 0.01), and allele A of rs17044552 was significantly lower in the progression group (11.5% vs 16.4%, P = 0.01). The odds ratio (OR) of these 2 SNPs were 1.42 [95% confidence interval (95% CI) 1.09-1.88] and 0.65 (95% CI 0.47-0.91), respectively. As for the allele frequencies of the other 51 SNPs, no significant difference was found between the 2 groups.

CONCLUSION

ScoliScore could not be able to predict the curve progression of AIS in Chinese Han population. However, the role of this test in other populations cannot be totally excluded, and additional replication studies in other ethnic groups are warranted to evaluate the significance of these SNPs.

LEVEL OF EVIDENCE

4.

Adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is the most common form of structural spinal deformities that have a radiological lateral Cobb angle - a measure of spinal curvature - of ≥10(°). AIS affects between 1% and 4% of adolescents in the early stages of puberty and is more common in young women than in young men. The condition occurs in otherwise healthy individuals and currently has no recognizable cause. In the past few decades, considerable progress has been made towards understanding the clinical patterns and the three-dimensional pathoanatomy of AIS. Advances in biomechanics and technology and their clinical application, supported by limited evidence-based research, have led to improvements in the safety and outcomes of surgical and non-surgical treatments. However, the definite aetiology and aetiopathogenetic mechanisms that underlie AIS are still unclear. Thus, at present, both the prevention of AIS and the treatment of its direct underlying cause are not possible.

Predictors of spine deformity progression in adolescent idiopathic scoliosis: A systematic review with meta-analysis

AIM: To evaluate published data on the predictors of progressive adolescent idiopathic scoliosis (AIS) in order to evaluate their efficacy and level of evidence.

METHODS: Selection criteria: (1) study design: randomized controlled clinical trials, prospective cohort studies and case series, retrospective comparative and none comparative studies; (2) participants: adolescents with AIS aged from 10 to 20 years; and (3) treatment: observation, bracing, and other. Search method: Ovid MEDLINE, Embase, the Cochrane Library, PubMed and patent data bases. All years through August 2014 were included. Data were collected that showed an association between the studied characteristics and the progression of AIS or the severity of the spine deformity. Odds ratio (OR), sensitivity, specificity, positive and negative predictive values were also collected. A meta-analysis was performed to evaluate the pooled OR and predictive values, if more than 1 study presented a result. The GRADE approach was applied to evaluate the level of evidence.

RESULTS: The review included 25 studies. All studies showed statistically significant or borderline association between severity or progression of AIS with the following characteristics: (1) An increase of the Cobb angle or axial rotation during brace treatment; (2) decrease of the rib-vertebral angle at the apical level of the convex side during brace treatment; (3) initial Cobb angle severity (> 25^o); (4) osteopenia; (5) patient age < 13 years at diagnosis; (6) premenarche status; (7) skeletal immaturity; (8) thoracic deformity; (9) brain stem vestibular dysfunction; and (10) multiple indices combining radiographic, demographic, and physiologic characteristics. Single nucleotide polymorphisms of the following genes: (1) calmodulin 1; (2) estrogen receptor 1; (3) tryptophan hydroxylase 1; (3) insulin-like growth factor 1; (5) neurotrophin 3; (6) interleukin-17 receptor C; (7) melatonin receptor 1B, and (8) ScoliScore test. Other predictors included: (1) impairment of melatonin signaling in osteoblasts and peripheral blood mononuclear cells (PBMC); (2) G-protein signaling dysfunction in PBMC; and (3) the level of platelet calmodulin. However, predictive values of all these findings were limited, and the levels of evidence were low. The pooled result of brace treatment outcomes demonstrated that around 27% of patents with AIS experienced exacerbation of the spine deformity during or after brace treatment, and 15% required surgical correction. However, the level of evidence is also low due to the limitations of the included studies.

CONCLUSION: This review did not reveal any methods for the prediction of progression in AIS that could be recommended for clinical use as diagnostic criteria.

Predicting success or failure of brace treatment for adolescents with idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is a three-dimensional spinal deformity. Brace treatment is a common non-surgical treatment, intended to prevent progression (worsening) of the condition during adolescence. Estimating a braced patient's risk of progression is an essential part of planning treatment, so method for predicting this risk would be a useful decision support tool for practitioners. This work attempts to discover whether failure of brace treatment (progression) can be predicted at the start of treatment. Records were obtained for 62 AIS patients who had completed brace treatment. Subjects were labeled as "progressive" if their condition had progressed despite brace treatment and "non-progressive" otherwise. Wrapper-based feature selection selected two useful predictor variables from a list of 14 clinical measurements taken from the records. A logistic regression model was trained to classify patients as "progressive" or "non-progressive" using these two variables. The logistic regression model's simplicity and interpretability should facilitate its clinical acceptance. The model was tested on data from an additional 28 patients and found to be 75 % accurate. This accuracy is sufficient to make the predictions clinically useful. It can be used online: http://www.ece.ualberta.ca/~dchalmer/SimpleBracePredictor.html .

Monitoring for idiopathic scoliosis curve progression using surface topography asymmetry analysis of the torso in adolescents

BACKGROUND CONTEXT

At first visit and each clinical follow-up session, patients with adolescent idiopathic scoliosis (AIS) undergo radiographic examination, from which the Cobb angle is measured. The cumulative exposure to X-ray radiation justifies efforts in developing noninvasive methods for scoliosis monitoring.

PURPOSE

To determine the capability of the three-dimensional markerless surface topography (ST) asymmetry analysis to detect ≥5° progression in the spinal curvature in patients with AIS over 1-year follow-up interval.

STUDY DESIGN/SETTING

Cross-sectional study in a specialized scoliosis clinic.

PATIENT SAMPLE

In this study, baseline and 1-year follow-up full torso ST scans of 100 patients with AIS were analyzed using three-dimensional markerless asymmetry analysis.

OUTCOME MEASURES

Patients with ΔCobb≥5° and ΔCobb<5° were categorized into progression and nonprogression groups, respectively.

METHODS

The ST scan of each full torso was analyzed to calculate the best plane of symmetry by minimizing the distances between the torso and its reflection about the plane of symmetry. Distance between the torso and its reflection was measured and displayed as deviation color maps. The difference of ST measurements between two successive acquisitions was used to determine if the scoliosis has progressed at least 5° or not. The classification tree technique was implemented using the local deformity of the torso in the thoracic-thoracolumbar (T-TL) and lumbar (L) regions to categorize curves into progression and nonprogression groups. The change in maximum deviation and root mean square of the deviations in the torso were the parameters effective in capturing the curve progression. Funding for this research is provided by the Scoliosis Research Society, and Women and Children's Health Research Institute.

RESULTS

The classification model detected 85.7% of the progression and 71.6% of the nonprogression cases. The resulting false-negative rate of 4% for T-TL curves, representing the proportion of undetected progressions, confirmed that the technique shows promise to monitor the progression of T-TL scoliosis curves. Although 100% L curves with progression were detected using the deviation color maps of the torsos, because of the small number of analyzed L curves, further research is needed before the efficiency of the method in capturing the L curves with progression is confirmed.

CONCLUSIONS

Using the developed classification tree for the patients analyzed in this study, 43% of nonprogression cases between two visits would not have to undergo an X-ray examination.

Reliability and accuracy of ultrasound measurements with and without the aid of previous radiographs in adolescent idiopathic scoliosis (AIS)

PURPOSE

The objectives of this preliminary study were to assess the reliability and accuracy of ultrasound (US) for measuring coronal curvature with and without the aid of a previous radiograph, and to evaluate the ability of US to detect curve progression in adolescent idiopathic scoliosis (AIS) patients.

METHODS

Four raters measured 20 AIS US images twice at one-week intervals. Intra-rater reliability and correlation with radiograph were investigated with (rater 1) and without (raters 2-4) the aid of a previous radiograph. The center of lamina (COL) method was used to approximate the Cobb angle.

RESULTS

Thirty-six curves were identified. All raters showed high intra-rater reliability (ICC[2,1] >0.80). With the aid of a previous radiograph, rater 1 showed higher correlation with radiograph (ICC[2,1] = 0.86), better standard error of measurement (SEM = 2.2°), and improved error index of selecting end-vertebrae (EI = 1.34), but no statistical improvement of intra-rater reliability (p > 0.05). For rater 2-4, the range of the ICC[2,1] values between US and radiograph measurements, the SEM value, and the range of the EI values were 0.70°-0.72°, 3.3°, and 1.65°-2.36°, respectively. Specificity and sensitivity of US for detecting curve progression were 0.91 and 0.83, respectively.

CONCLUSIONS

Using a previous radiograph as a measurement aid helped the user to measure coronal curvature from US images, and improved the accuracy of end-vertebrae selection. US showed high sensitivity and specificity for detecting curve progression, indicating that US may be a suitable, radiation-free alternative for monitoring patients with AIS who have mild or moderate curves.

Human experts' and a fuzzy model's predictions of outcomes of scoliosis treatment: a comparative analysis

Brace treatment is the most commonly used nonsurgical treatment for adolescents with idiopathic scoliosis. However, brace treatment is not always successful and the factors influencing its success are not completely clear. This makes treatment outcome difficult to predict. A computer model which can accurately predict treatment outcomes could potentially provide valuable treatment recommendations. This paper describes a fuzzy system that includes a prediction model and a decision support engine. The model was constructed using conditional fuzzy c-means clustering to discover patterns in retrospective patient data. The model's ability to predict treatment outcome was compared to the ability of eight Scoliosis experts. The model and experts each predicted treatment outcome retrospectively for 28 braced patients, and these predictions were compared to the actual outcomes. The model outperformed all but one expert individually and performed similarly to the experts as a group. These results suggest that the fuzzy model is capable of providing meaningful treatment recommendations. This study offers the first model for this application whose performance has been shown to be at or above the human expert level.

Factors relating to curve progression in female patients with adolescent idiopathic scoliosis treated with a brace

PURPOSE

One single factor cannot by itself predict curve progression accurately. The aim of this study is to determine multiple related factors in predicting the progression of scoliosis in girls with adolescent idiopathic scoliosis (AIS) treated with bracing.

METHODS

Eighty-nine female patients with AIS treated with a brace were reviewed. A series of parameters were consecutively measured and documented during the period of follow-up. Curve behavior between the first visit and final follow-up was analyzed. Several different parameters which may contribute to progression of curve were selected by a logistic regression analysis.

RESULTS

Mean age of patients at the first visit was 13.6 (10-16) years. The patients were followed for 12-72 months (mean 24.8 months). At the last visit, 21 patients (23.60 %) had curve progression more than 5°. After performing a logistic regression analysis, Risser sign less than two, the magnitude of the major curve at pre-brace greater than 35°, apical vertebral rotation beyond grade III, and the spinal length increasing larger than 20 mm in 1 year were found to be factors which predict the progression of more than 5°.

CONCLUSIONS

This study suggests that Risser sign, the magnitude of the major curve at pre-brace, apical vertebral rotation, and the spinal length increasing velocity are important factors to predict progression in the girls with AIS. Risser sign cannot predict the progression of scoliosis accurately unless combined with other related parameters.

Hepatocellular carcinoma: surveillance CT schedule after hepatectomy based on risk stratification

PURPOSE

To evaluate alternative schedules for surveillance computed tomography (CT) for patients who underwent hepatectomy for hepatocellular carcinoma ( HCC hepatocellular carcinoma ) and to demonstrate an appropriate schedule on the basis of stratification for risk of recurrence.

MATERIALS AND METHODS

CT and pathologic reports for consecutive patients with HCC hepatocellular carcinoma who underwent hepatectomy at one institution were evaluated with institutional review board approval. Univariate and multivariate analyses were performed to identify risk factors for recurrence. Patients were categorized into risk groups on the basis of classification and regression tree analysis. Average recurrence detection rates ( RDR recurrence detection rate s) between consecutive CT scans were calculated for existing and alternative surveillance schedules for each risk group, and the difference in RDR recurrence detection rate was determined by using the Student t test. A P value of less than .05 was considered to indicate a significant difference. Expected delay in diagnosis was also computed for the alternative surveillance schedules for each risk group.

RESULTS

Two hundred sixty patients (216 men; mean age, 56.0 years ± 22.5) underwent 2705 CT studies. Independent risk factors for recurrence were microvascular invasion (P = .001), cirrhosis (P = .007), and tumor multiplicity (P = .001). Three risk groups (low, intermediate, and high) were identified. For low- and intermediate-risk groups, average RDR recurrence detection rate was not significantly different in the first 2 years after hepatectomy when the interval was extended from 3 months (3.3% and 4.6%, respectively) to 4 months (4.3% [expected delay, 16 days] and 6.1% [expected delay, 18 days], respectively) or for the subsequent 3 years when the interval was extended from 6 months (1.3% and 3.5%, respectively) to 12 months (2.5% [expected delay, 72 days] and 7.0% [expected delay, 103 days], respectively). This alternative schedule included five (35.7%) fewer CT scans than the 14 in the original schedule, and a reduction in radiation dose and cost during the 5-year follow-up period.

CONCLUSION

Posthepatectomy surveillance CT schedules may be tailored and optimized according to stratification by risk of recurrence to reduce the frequency of CT scans without compromising surveillance benefits.

Comparison of the sagittal profiles among thoracic idiopathic scoliosis patients with different Cobb angles and growth potentials

Background

Previous studies have demonstrated that pelvic incidence and sacral slope are significantly greater in idiopathic scoliosis patients compared with normal adolescents. However, whether these sagittal parameters are related to the progression of scoliosis remain unknown. The present was designed to determine the differences in the sagittal profiles among thoracic idiopathic scoliosis patients with different potentials for curve progression.

Methods

Ninety-seven outpatient idiopathic scoliosis patients enrolled from June 2008 to June 2011 were divided to three groups according to different Cobb angles and growth potentials: (1) non-progression of thoracic curve group, Risser sign of 5 and Cobb’s angle < 40°; (2) moderate progression of thoracic curve group, Risser sign of 5 and Cobb’s angle ≥ 40°; and (3) severe progression of thoracic curve group, Risser sign ≤ 3 and Cobb’s angle ≥ 40°. All patients underwent whole spinal anteroposterior and lateral X-ray in standing position, and the sagittal parameters were measured, including thoracic kyphosis, lumbar lordosis, sacral slope, pelvic incidence, and pelvic tilt.

Results

The average thoracic scoliosis Cobb’s angle in the non-progression group was significantly less than that in the moderate progression group (P < 0.01) and severe progression group (P < 0.01), but there was no statistical difference in the average thoracic scoliosis Cobb’s angle between the severe progression group and moderate progression group. The average thoracic kyphosis angle in the severe progression group (9° ± 4°) was significantly smaller than that in the non-progression group (18° ± 6°, P < 0.01) and moderate progression group (14° ± 5°, P < 0.05). No statistical differences were present in the average lumbar lordosis, sacral slope, pelvic incidence, and pelvic tilt among the three groups.

Conclusions

Thoracic hypokyphosis is strongly related with the curve progression in thoracic idiopathic scoliosis patients, but not pelvic sagittal profiles.