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Ian G. Dorward - One of the best experts on this subject based on the ideXlab platform.
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Idiopathic Scoliosis and the vestibular system
European Spine Journal, 2015Co-Authors: Ammar H. Hawasli, Timothy E. Hullar, Ian G. DorwardAbstract:Purpose Despite its high prevalence, the etiology underlying Idiopathic Scoliosis remains unclear. Although initial scrutiny has focused on genetic, biochemical, biomechanical, nutritional and congenital causes, there is growing evidence that aberrations in the vestibular system may play a role in the etiology of Scoliosis. In this article, we discuss putative mechanisms for adolescent Idiopathic Scoliosis and review the current evidence supporting a role for the vestibular system in adolescent Idiopathic Scoliosis. Methods A comprehensive search of the English literature was performed using PubMed ( http://www.ncbi.nlm.nih.gov/pubmed ). Research articles studying interactions between adolescent Idiopathic Scoliosis and the vestibular system were selected and evaluated for inclusion in a literature review. Results Eighteen manuscripts of level 3–4 clinical evidence to support an association between adolescent Idiopathic Scoliosis (AIS) and dysfunction of the vestibular system were identified. These studies include data from physiologic and morphologic studies in humans. Clinical data are supported by animal model studies to suggest a causative link between the vestibular system and AIS. Conclusions Clinical data and a limited number of animal model studies suggest a causative role of the vestibular system in AIS, although this association has not been reproduced in all studies.
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Idiopathic Scoliosis and the vestibular system
European Spine Journal, 2015Co-Authors: Ammar H. Hawasli, Timothy E. Hullar, Ian G. DorwardAbstract:Purpose Despite its high prevalence, the etiology underlying Idiopathic Scoliosis remains unclear. Although initial scrutiny has focused on genetic, biochemical, biomechanical, nutritional and congenital causes, there is growing evidence that aberrations in the vestibular system may play a role in the etiology of Scoliosis. In this article, we discuss putative mechanisms for adolescent Idiopathic Scoliosis and review the current evidence supporting a role for the vestibular system in adolescent Idiopathic Scoliosis. Methods A comprehensive search of the English literature was performed using PubMed ( http://www.ncbi.nlm.nih.gov/pubmed ). Research articles studying interactions between adolescent Idiopathic Scoliosis and the vestibular system were selected and evaluated for inclusion in a literature review. Results Eighteen manuscripts of level 3–4 clinical evidence to support an association between adolescent Idiopathic Scoliosis (AIS) and dysfunction of the vestibular system were identified. These studies include data from physiologic and morphologic studies in humans. Clinical data are supported by animal model studies to suggest a causative link between the vestibular system and AIS. Conclusions Clinical data and a limited number of animal model studies suggest a causative role of the vestibular system in AIS, although this association has not been reproduced in all studies.
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Idiopathic Scoliosis and the vestibular system.
European Spine Journal, 2014Co-Authors: Ammar H. Hawasli, Timothy E. Hullar, Ian G. DorwardAbstract:Purpose Despite its high prevalence, the etiology underlying Idiopathic Scoliosis remains unclear. Although initial scrutiny has focused on genetic, biochemical, biomechanical, nutritional and congenital causes, there is growing evidence that aberrations in the vestibular system may play a role in the etiology of Scoliosis. In this article, we discuss putative mechanisms for adolescent Idiopathic Scoliosis and review the current evidence supporting a role for the vestibular system in adolescent Idiopathic Scoliosis.
Charles-hilaire Rivard - One of the best experts on this subject based on the ideXlab platform.
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SpineCore treatment for juvenile Idiopathic Scoliosis
Scoliosis, 2010Co-Authors: Christine Coillard, Alin B Circo, Charles-hilaire RivardAbstract:The natural history of juvenile Idiopathic Scoliosis (patients who are least 4 years of age but younger than ten when the deformity is first identified) is usually a progression. In addition, patients who receive a diagnosis at five years or younger have a high chance of progression to a large curve, witch may lead to pulmonary and cardiac complications. The mainstay of conservative treatment for Scoliosis (juvenile as well as for the adolescent) is the brace. The purpose of this prospective interventional study was to evaluate the effectiveness of the Dynamic SpineCor brace for juvenile Idiopathic Scoliosis and to evaluate the stability of the spine after the weaning point.
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Melatonin signaling dysfunction in adolescent Idiopathic Scoliosis.
Spine, 2004Co-Authors: Alain Moreau, Charles-hilaire Rivard, Benoit Poitras, Da Shen Wang, Steve Forget, Bouziane Azeddine, Debora Angeloni, Franco Fraschini, H. Labelle, Guy GrimardAbstract:Study Design. In vitro assays were performed with bone-forming cells isolated from 41 patients with adolescent Idiopathic Scoliosis and 17 control patients exhibiting another type of Scoliosis or none. Objective. To determine whether a dysfunction of the melatonin-signaling pathway in tissues targeted by this hormone is involved in adolescent Idiopathic Scoliosis. Summary of Background Data. Pinealectomy in chicken has led to the formation of a scoliotic deformity, thereby suggesting that a melatonin deficiency may be at the source of adolescent Idiopathic Scoliosis. However, the relevance of melatonin in the etiopathogenesis of that condition is controversial because most studies have reported no significant change in circulating levels of melatonin in patients with adolescent Idiopathic Scoliosis. Methods. Primary osteoblast cultures prepared from bone specimens obtained intraoperatively during spine surgeries were used to test the ability of melatonin and Gpp(NH)p, a GTP analogue, to block cAMP accumulation induced by forskolin. In parallel, melatonin receptor and Gi protein functions were evaluated by immunohistochemistry and by coimmunoprecipitation experiments. Results. The cAMP assays demonstrated that melatonin signaling was impaired in osteoblasts isolated from adolescent Idiopathic Scoliosis patients to different degrees allowing their classification in 3 distinct groups based on their responsiveness to melatonin or Gpp(NH)p. Conclusion. Melatonin signaling is clearly impaired in osteoblasts of all patients with adolescent Idiopathic Scoliosis tested. Classification of patients with adolescent Idiopathic Scoliosis in 3 groups based on functional in vitro assays suggests the presence of distinct mutationsinterfering with the melatonin signal transduction. Posttranslational modifications affecting Gi protein function, such as serine residues phosphorylation, should be considered as one possible mechanism in the etiopathogenesis of AIS.
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Etiology of Idiopathic Scoliosis: current trends in research.
The Journal of Bone and Joint Surgery-American Volume, 2000Co-Authors: Thomas G. Lowe, Nancy H Miller, Michael Edgar, Joseph Y. Margulies, V. James Raso, Kent A. Reinker, Charles-hilaire RivardAbstract:Current population studies characterize Idiopathic Scoliosis as a single-gene disorder that follows the patterns of mendelian genetics, including variable penetrance and heterogeneity. The role of melatonin and calmodulin in the development of Idiopathic Scoliosis is likely secondary, with indirect effects on growth mechanisms. Reported abnormalities of connective tissue, skeletal muscle, platelets, the spinal column, and the rib cage are all thought to be secondary to the deformity itself. Although no consistent neurological abnormalities have been identified in patients with Idiopathic Scoliosis, it is possible that a defect in processing by the central nervous system affects the growing spine. The true etiology of Idiopathic Scoliosis remains unknown; however, it appears to be multifactorial.
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Relation between adolescent Idiopathic Scoliosis and morphologic somatotypes.
Spine, 1997Co-Authors: Richard Leblanc, Hubert Labelle, Charles-hilaire Rivard, Benoit PoitrasAbstract:STUDY DESIGN A prospective and controlled comparative study. OBJECTIVES To verify the difference in morphologic appearance between a group of adolescents with progressive adolescent Idiopathic Scoliosis and a control group of normal adolescents. SUMMARY OF BACKGROUND DATA In a previous retrospective study, the possibility of a relation between progressive adolescent Idiopathic Scoliosis and specific morphotypes was demonstrated. METHODS Fifty-two adolescent girls with progressive adolescent Idiopathic Scoliosis were compared with an age-matched control group of 62 unaffected girls using a classification technique based on morphologic somatotypes. Morphotypes were evaluated with standardized pre-established criteria based on Sheldon's technique. RESULTS Patients with progressive adolescent Idiopathic Scoliosis showed significantly less mesomorphism (mean value of 0.88 +/- 0.51) than control girls (mean value of 1.72 +/- 0.52). CONCLUSION Adolescent girls with progressive adolescent Idiopathic Scoliosis have a morphologic somatotype that is different from the normal adolescent population. Subjects with progressive adolescent Idiopathic Scoliosis are significantly less mesomorphic than control girls. This observation may be of value as a predictive factor for early identification of subjects with adolescent Idiopathic Scoliosis at greater risk of progression.
Matthew B. Dobbs - One of the best experts on this subject based on the ideXlab platform.
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Adolescent Idiopathic Scoliosis
Nature Reviews Disease Primers, 2015Co-Authors: Jack C. Cheng, Theodoros B Grivas, Alain Moreau, Matthew B. Dobbs, René M. Castelein, Winnie C. Chu, Aina J. Danielsson, Christina A. Gurnett, Keith D. Luk, Peter O. NewtonAbstract: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. Adolescent Idiopathic Scoliosis (AIS) is characterized by spinal curvature that develops early in adolescence. Although its causes are unknown, in this Primer, Cheng and colleagues discuss various hypotheses to explain the development and progression of AIS.
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Exome Sequencing Identifies a Rare HSPG2 Variant Associated with Familial Idiopathic Scoliosis
G3: Genes|Genomes|Genetics, 2014Co-Authors: Erin E. Baschal, Matthew B. Dobbs, Nelson L.s. Tang, Cambria I. Wethey, Kandice Swindle, Robin M. Baschal, Katherine Gowan, David M. Alvarado, Gabe Haller, Matthew R.g. TaylorAbstract:Idiopathic Scoliosis occurs in 3% of individuals and has an unknown etiology. The objective of this study was to identify rare variants that contribute to the etiology of Idiopathic Scoliosis by using exome sequencing in a multigenerational family with Idiopathic Scoliosis. Exome sequencing was completed for three members of this multigenerational family with Idiopathic Scoliosis, resulting in the identification of a variant in the HSPG2 gene as a potential contributor to the phenotype. The HSPG2 gene was sequenced in a separate cohort of 100 unrelated individuals affected with Idiopathic Scoliosis and also was examined in an independent Idiopathic Scoliosis population. The exome sequencing and subsequent bioinformatics filtering resulted in 16 potentially damaging and rare coding variants. One of these variants, p.Asn786Ser, is located in the HSPG2 gene. The variant p.Asn786Ser also is overrepresented in a larger cohort of Idiopathic Scoliosis cases compared with a control population (P = 0.024). Furthermore, we identified additional rare HSPG2 variants that are predicted to be damaging in two independent cohorts of individuals with Idiopathic Scoliosis. The HSPG2 gene encodes for a ubiquitous multifunctional protein within the extracellular matrix in which loss of function mutation are known to result in a musculoskeletal phenotype in both mouse and humans. Based on these results, we conclude that rare variants in the HSPG2 gene potentially contribute to the Idiopathic Scoliosis phenotype in a subset of patients with Idiopathic Scoliosis. Further studies must be completed to confirm the effect of the HSPG2 gene on the Idiopathic Scoliosis phenotype.
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Management of juvenile Idiopathic Scoliosis
Journal of Bone and Joint Surgery American Volume, 2007Co-Authors: Lawrence G. Lenke, Matthew B. DobbsAbstract:Idiopathic Scoliosis is a structural, lateral curvature of the spine for which no etiology has been established. Chronologically, Idiopathic Scoliosis can be categorized on the basis of the age of the patient at first identification of the deformity: infantile (birth to two years and eleven months), juvenile (three years to nine years and eleven months), and adolescent (ten years to seventeen years and eleven months). Thus, this article will describe the scoliotic deformities of patients who are at least three years of age but younger than ten years of age when the deformity is first identified. It has been demonstrated that spinal growth is fairly steady during this juvenile period1. For this reason, Dickson and Archer believed that true juvenile-onset Scoliosis was rare enough not to warrant a separate category. They proposed a two-group classification that included early onset (five years of age or less) and late onset (six years of age and older) Scoliosis2. In addition, patients who receive a diagnosis of Scoliosis at five years of age or younger have a much higher chance of having a large curve develop, which may lead to pulmonary complications and cor pulmonale1,3. In this paper, we adhere to the classic age-at-onset definition as described by Dickson and Archer but do not describe adolescent Idiopathic Scoliosis. Between 12% and 21% of patients with Idiopathic Scoliosis can be included in the category of juvenile Idiopathic Scoliosis4, the gradual transition period between infantile Idiopathic Scoliosis and adolescent Idiopathic Scoliosis. This is certainly true with regard to sex predilection: the female-to-male ratio is 1:1 in children between three and six years of age, 2:1 to 4:1 overall in children who are at least three but less than ten years of age5, and 8:1 …
F. Clerget-darpoux - One of the best experts on this subject based on the ideXlab platform.
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NEW DISEASE GENE LOCATION AND HIGH HETEROGENEITY IN Idiopathic Scoliosis
2012Co-Authors: P. Edery, P. Margaritte-jeannin, B. Biot, A. Labalme, J. Bernard, J. Chastang, B. Kassai, M. Plays, F. Moldovan, F. Clerget-darpouxAbstract:Introduction Idiopathic Scoliosis is a spine disorder of unknown origin with a prevalence of 1·5-3% in the general population. Apart from the large multifactorial form sample of Idiopathic Scoliosis, there is a good evidence for the existence of a monogenic subgroup in which the disease is inherited in a dominant manner. However, results from published work suggest a strong heterogeneity in locations of the mutated genes. Methods With a high resolution genome-wide scan, we undertook linkage analyses in three large multigenerational families with Idiopathic Scoliosis compatible with dominant inheritance, including 11–12 affected members or obligate carriers. Results In two of these families, our results suggested intrafamilial genetic heterogeneity, whereas in the other we recorded a perfect marker disease co-segregation in two distinct chromosomal regions. We can state that one of these two locations is a novel Idiopathic Scoliosis disease gene locus, since the probability of having by chance this perfect co-segregation twice in the genome is very low (p=0·001). Lastly, in all three families studied, we excluded compatibility with linkage to the previously mapped dominant Idiopathic Scoliosis loci on chromosomes 19p13.3, 17p11.2, 9q34, 17q25, and 18q. Conclusions Our findings confirm that there is a high genetic heterogeneity within the subgroup of dominant forms of Idiopathic Scoliosis.
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New disease gene location and high genetic heterogeneity in Idiopathic Scoliosis
European Journal of Human Genetics, 2011Co-Authors: P. Edery, P. Margaritte-jeannin, B. Biot, A. Labalme, J. Chastang, B. Kassai, F. Moldovan, Jean-claude Bernard, Marie-helene Plais, F. Clerget-darpouxAbstract:Idiopathic Scoliosis is a spine disorder of unknown origin with 1.5-3% prevalence in the general population. Besides the large multifactorial form sample of Idiopathic Scoliosis, there is a good evidence for the existence of a monogenic subgroup in which the disease is inherited in a dominant manner. However, results from literature suggest a strong heterogeneity in the locations of the mutated genes. Using a high resolution genome-wide scan, we performed linkage analyses in three large multigenerational Idiopathic Scoliosis families compatible with dominant inheritance including 9 to 12 affected members or obligate carriers. In two of these families, our results suggested intra-familial genetic heterogeneity whereas, in the other, we observed a perfect marker disease co-segregation in two regions at 3q12.1 and 5q13.3. We can state that one of these two locations is a novel Idiopathic Scoliosis disease gene locus, since the probability of having this perfect co-segregation twice by chance in the genome is very low (p=0.001). Lastly, in all three families studied, linkage to the previously mapped dominant Idiopathic Scoliosis loci on chromosomes 19p13.3, 17p11.2, 9q34, 17q25 and 18q is unlikely, confirming that there is a high genetic heterogeneity within the subgroup of dominant forms of Idiopathic Scoliosis.
Michael P. Kelly - One of the best experts on this subject based on the ideXlab platform.
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A new modular radiographic classification of adult Idiopathic Scoliosis as an extension of the Lenke classification of adolescent Idiopathic Scoliosis
Spine Deformity, 2020Co-Authors: Joseph A. Osorio, Griffin R. Baum, Richard P. Menger, Patrick C. Reid, Marc D. Dyrszka, Louis F. Amorosa, Zeeshan M. Sardar, Christopher E. Mandigo, Peter D. Angevine, Michael P. KellyAbstract:Purpose To propose and test the reliability of a radiographic classification system for adult Idiopathic Scoliosis. Methods A three-component radiographic classification for adult Idiopathic Scoliosis consisting of curve type, a lumbosacral modifier, and a global alignment modifier is presented. Twelve spine surgeons graded 30 pre-marked cases twice, approximately 1 week apart. Case order was randomized between sessions. Results The interrater reliability (Fleiss’ kappa coefficient) for curve type was 0.660 and 0.798, for the lumbosacral modifier 0.944 and 0.965, and for the global alignment modifier 0.922 and 0.916, for round 1 and 2 respectively. Mean intrarater reliability was 0.807. Conclusions This new radiographic classification of adult Idiopathic Scoliosis maintains the curve types from the Lenke classification and introduces the lumbosacral and global alignment modifiers. The reliability of the lumbosacral modifier and global alignment modifier shows near perfect agreement, and sets the foundation for further studies to validate the reliability, utility, and applicability of this classification system.
