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Purpose: The prone position can lead to anatomical compression of the thoracic cavity resulting in reduced cardiac output, especially in the context of chest wall deformities commonly present in patients with scoliosis. There are no protocols for using transesophageal echocardiography (TEE) to optimize prone positioning and for safe use of TEE during cases requiring neuromonitoring., Clinical Features: We present a case of a 23-yr-old male with Cornelia de Lange syndrome undergoing elective posterior spinal fusion for syndromic scoliosis who developed severe refractory hypotension and cardiac arrest in the prone position. After hemodynamic stabilization in the intensive care unit, the patient returned to the operating room on postoperative day 2 for completion of his spinal fusion. Transesophageal echocardiography determined the optimal position of longitudinal bolster placements associated with minimal left ventricular compression in the supine position. The patient was then proned and intraoperative hemodynamics during the second surgery remained stable. Owing to the special considerations of using TEE in the prone position with neuromonitoring, we describe technical aspects to consider to protect the equipment and patient., Conclusion: Patients with compliant chest walls or thoracic deformities are at risk of hemodynamic instability in the prone position. Intraoperative TEE can be used in the supine patient prior to proning to determine optimal longitudinal bolster positioning to minimize cardiac compression. Transesophageal echocardiography used during spine surgery in the prone position with neuromonitoring and motor-evoked potentials requires special considerations for patient safety., (© 2022. Canadian Anesthesiologists' Society.)

Background: Variability in surgical strategies for the treatment of adolescent idiopathic scoliosis (AIS) has been demonstrated despite the existence of classifications to guide selection of AIS curves to include in fusion. Decision trees and rule-based algorithms have demonstrated their potential to improve reliability of AIS classification because of their systematic approach and they have also been proposed in algorithms for selection of instrumentation levels in scoliosis. Our working hypothesis is that a rule-based algorithm with a knowledge base extracted from the literature can efficiently output surgical strategies alternatives for a given AIS case. Our objective is to develop a rule-based algorithm based on peer-reviewed literature to output alternative surgical strategies for approach and levels of fusion., Methods: A literature search of all English Manuscripts published between 2000 and December 2009 with Pubmed and Google scholar electronic search using the following keywords: "adolescent idiopathic scoliosis" and "surgery" alternatively with "levels of fusion" or "approach". All returned abstracts were screened for contents that could contain rules to include in the knowledge base. A dataset of 1,556 AIS cases treated surgically was used to test the surgical strategy rule-based algorithm (SSRBA) and evaluate how many surgical treatments are covered by the algorithm. The SSRBA was programmed using Matlab. Descriptive statistic was used to evaluate the ability of the rule-based algorithm to cover all treatment alternatives., Results: A SSRBA was successfully developed following Lenke classification's concept that the spine is divided into three curve segments [proximal thoracic (PT), main thoracic (MT) and thoracolumbar/lumbar (TL)]. Each of the 1,556 AIS patients in the dataset was ran through the SSRBA. It proposed an average of 3.78 (±2.06) surgical strategies per case. Overall, the SSRBA is able to match the treatment offered by the surgeon in approach and level of fusion 70 % of the time (with one vertebral level leeway)., Conclusion: This study is to the author's knowledge the first attempt at proposing an algorithm to output all surgical alternatives for a given AIS case. It uses a rule-based algorithm with a knowledge base extracted from peer-reviewed literature in an area with great variability. When tested against a database of AIS patients treated surgically, the SSRBA developed has the ability to propose a surgical plan with respect to approach and levels of fusion that match the surgeon's plan in a great majority of cases. Since this SSRBA seems to output multiple valid surgical strategies, it could allow the comparisons of various strategies and the outcomes achieved in similar cases in large databases for a given case and guide surgical treatment.

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.

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., (Copyright © 2014 Elsevier Inc. All rights reserved.)

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 © 2013 Elsevier Inc. All rights reserved.)

Adolescent idiopathic scoliosis (AIS) is a complex spinal deformity whose assessment and treatment present many challenges. Computer applications have been developed to assist clinicians. A literature review on computer applications used in AIS evaluation and treatment has been undertaken. The algorithms used, their accuracy and clinical usability were analyzed. Computer applications have been used to create new classifications for AIS based on 2D and 3D features, assess scoliosis severity or risk of progression and assist bracing and surgical treatment. It was found that classification accuracy could be improved using computer algorithms that AIS patient follow-up and screening could be done using surface topography thereby limiting radiation and that bracing and surgical treatment could be optimized using simulations. Yet few computer applications are routinely used in clinics. With the development of 3D imaging and databases, huge amounts of clinical and geometrical data need to be taken into consideration when researching and managing AIS. Computer applications based on advanced algorithms will be able to handle tasks that could otherwise not be done which can possibly improve AIS patients' management. Clinically oriented applications and evidence that they can improve current care will be required for their integration in the clinical setting.

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 radiographs. It should be used at the first visit and for scoliosis follow-up to assess skeletal maturity and correlation with the curve acceleration phase.

Study Design: The assignment of adolescent idiopathic scoliosis (AIS) curves into curve types (1-6), as described by Lenke et al, was evaluated by 12 independent observers using the original description versus a decisional tree algorithm., Objective: To determine whether a decision tree algorithm can improve classification accuracy using the Lenke classification for AIS., Summary of Background Data: Curve type classification in AIS relies on several parameters to consider, and its relative complexity has lead to conflicting studies that reported fair-to-excellent interobserver reliability. King's classification reliability was shown to be improved using a rule-based automated algorithm. No similar algorithm for Lenke's classification currently exists., Methods: A clinical diagram derived from a decision tree was developed to help clinicians classify AIS curves. Twelve clinicians and research assistants were asked to classify AIS curves using 2 methods: the original Lenke chart alone and the decision tree diagram in addition to the Lenke Chart. Wilcoxon ranking tests were used to evaluate any difference in classification accuracy and speed for both methods. Mann-Whitney tests were used to compare experts' and nonexperts' results. Pearson correlation was calculated to evaluate the relationship between accuracy and time taken to classify. RESULTS.: Use of the decision tree for curve type determination improved classification accuracy from 77.2% to 92.9% (P = 0.005) without requiring more time to classify. This improvement was statistically significant (P < 0.05). A statistically significant correlation between accuracy and time spent classifying when the decision tree is used was also observed (R = 0.62, P = 0.032)., Conclusion: Transfer of a computer algorithm, a decision tree, to a clinical diagram improved both accuracy ofAIS classification. Algorithmic diagrams could prove beneficial to increase classification reliability due to their systematic approach.

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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]