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Purpose: A single nucleotide polymorphism in the promoter region of the estrogen receptor alpha gene ( ESR1), rs9340799, has been linked with adolescent idiopathic scoliosis (AIS) in several association studies with limited sample size and inconsistent findings. A systematic review can provide a comprehensive appraisal of literature evidence and a meta-analysis can obtain a more precise estimate of any association. The purpose of the present study was to assess and synthesize the currently available evidence on the association between rs9340799 and AIS by conducting a systematic review and meta-analysis. Methods: This review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. PubMed (MEDLINE), EMBASE, Scopus and HuGE Literature Finder databases were systematically searched to identify relevant studies following a sensitive strategy. Summary odds ratios and corresponding 95 % confidence intervals (95 % CI) were estimated using the fixed-effect inverse variance model for allelic (G vs. A) and genotypic comparisons. Results: Meta-analysis of four studies ( n = 1,827 AIS cases and n = 1,253 controls) found a non-significant association between rs9340799 and AIS (allelic odds ratio 1.09, 95 % CI 0.96-1.23, p = 0.17). Conclusions: When examined in isolation, the rs9340799 polymorphism does not appear to be a likely susceptibility variant for AIS predisposition. However, rs9340799 may be associated with AIS severity, progression and treatment; further investigation is necessary to confirm these potential associations. [ABSTRACT FROM AUTHOR]

Abstract: Background context: Variability in classifying and selecting levels of fusion in adolescent idiopathic scoliosis (AIS) has been repeatedly documented. Several computer algorithms have been used to classify AIS based on the geometrical features, but none have attempted to analyze its treatment patterns. Purpose: To use self-organizing maps (SOM), a kind of artificial neural networks, to reliably classify AIS cases from a large database. To analyze surgeon's treatment pattern in selecting curve regions to fuse in AIS using Lenke classification and SOM. Study design: This is a technical concept article on the possibility and benefits of using neural networks to classify AIS and a retrospective analysis of AIS curve regions selected for fusion. Patient sample: A total of 1,776 patients surgically treated for AIS were prospectively enrolled in a multicentric database. Cobb angles were measured on AIS patient spine radiographies, and patients were classified according to Lenke classification. Outcome measures: For each patient in the database, surgical approach and levels of fusion selected by the treating surgeon were recorded. Methods: A Kohonen SOM was generated using 1,776 surgically treated AIS cases. The quality of the SOM was tested using topological error. Percentages of prediction of fusion based on Lenke classification for each patient in the database and for each node in the SOM were calculated. Lenke curve types, treatment pattern, and kappa statistics for agreement between fusion realized and fusion recommended by Lenke classification were plotted on each node of the map. Results: The topographic error for the SOM generated was 0.02, which demonstrates high accuracy. The SOM differentiates clear clusters of curve type nodes on the map. The SOM also shows epicenters for main thoracic, double thoracic, and thoracolumbar/lumbar curve types and transition zones between clusters. When cases are taken individually, Lenke classification predicted curve regions fused by the surgeon in 46% of cases. When those cases are reorganized by the SOM into nodes, Lenke classification predicted the curve regions to fuse in 82% of the nodes. Agreement with Lenke classification principles was high in epicenters for curve types 1, 2, and 5, moderate in cluster for curve types 3, 4, and 6, and low in transition zones between curve types. Conclusions: An AIS SOM with high accuracy was successfully generated. Lenke classification principles are followed in 46% of the cases but in 82% of the nodes on the SOM. The SOM highlights the tendency of surgeons to follow Lenke classification principles for similar curves on the SOM. Self-organizing map classification of AIS could be valuable to surgeons because it bypasses the limitations imposed by rigid classification such as cutoff values on Cobb angle to define curve types. It can extract similar cases from large databases to analyze and guide treatment. [Copyright &y& Elsevier]

The article presents a study which investigates the capability of a decision tree algorithm to improve classification accuracy through the use of Lenke classification for adolescent idiopathic scoliosis (AIS). The study employs various methods including a clinical diagram to sort out AIS curves and the Wilcoxon ranking tests to assess the difference in classification accuracy and speed. Moreover, the study reveals that tree algorithm improves the classification accuracy to 92.9%.

Background: The Risser sign can be assessed with the United States method or the European method. The Tanner-Whitehouse method estimates skeletal age on the basis of hand radiography and digital skeletal age. Digital skeletal age scores between 400 and 425 are associated with the beginning of the curve acceleration phase or peak growth velocity in adolescent idiopathic scoliosis. The first objective of the present study was to evaluate the agreement between the two Risser grading systems. The second objective was to identify which grading system best predicts a digital skeletal age of between 400 and 425. The third objective was to explore a new system that could be used to replace the Risser method. Methods: One hundred female patients with adolescent idiopathic scoliosis were recruited in this cross-sectional descriptive study. Each patient was evaluated with posteroanterior spine and hand radiographs. The Risser sign was measured according to both the United States and European grading systems. Digital skeletal age was calculated, and triradiate cartilage ossification was assessed. Results: With use of kappa statistics, moderate agreement between the United States and European grading systems was seen. Risser stages alone were not good predictors of the curve acceleration phase. A new system with three groups was tested, and the second group (Risser 0 with closed triradiate cartilage and Risser 1) was the best predictor of a digital skeletal age score of between 400 and 425. Conclusions: Two Risser grading systems coexist, and the agreement between them is moderate. No Risser stage was found to be a good clinical landmark for the beginning of the curve acceleration phase of adolescent idiopathic scoliosis. A new group, Risser 0 with closed triradiate cartilage and Risser 1, was the best predictor of the beginning of the curve acceleration phase. This new system is easy to implement and is based on findings that are available on spine radio- graphs. It should be used at the first visit and for scoliosis follow-up to assess skeletal maturity and correlation with the curve acceleration phase. [ABSTRACT FROM AUTHOR]

Background context The rs11190870 single nucleotide polymorphism in the 3'-flanking region of the LBX1 gene has been implicated in the etiology of adolescent idiopathic scoliosis (AIS). A thorough appraisal of the evidence supporting this association has not been previously attempted. Purpose To provide a comprehensive assessment and synthesis of the currently available evidence on the association between rs11190870 and AIS. Study design A systematic review and meta-analysis. Methods This review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. PubMed (MEDLINE), EMBASE, Scopus, and HuGE Literature Finder databases were systematically searched through November 2013 to identify relevant studies following a sensitive strategy. Summary odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using the fixed-effect inverse variance model for allelic (T vs. C) and genotypic comparisons. Results Meta-analysis of four studies conducted in East Asian populations (n=3,215 AIS cases and n=15,347 controls) found a highly statistically significant and robust association between rs11190870 and AIS. Comparison of summary ORs indicated a codominant model effect of the T allele. Carriers of the TC and TT genotypes were 69% (OR=1.69, 95% CI: 1.48–1.94, p<.001) and 162% (OR=2.62, 95% CI: 2.28–3.02, p<.001), respectively, more likely to have AIS compared with carriers of the CC genotype. Conclusions Based on a comprehensive analysis of the currently available evidence, rs11190870 is likely a susceptibility variant for AIS in East Asians. Further investigation of this association is necessary in other populations. [ABSTRACT FROM AUTHOR]