Pathogenesis Of Scoliosis Research Articles

Genetics and pathogenesis of scoliosis

BackgroundScoliosis is defined as a lateral spine curvature of at least 10° with vertebral rotation, as seen on a posterior-anterior radiograph, often accompanied by reduced thoracic kyphosis. Scoliosis affects all age groups: idiopathic scoliosis is the most common spinal disorder in children and adolescents, while adult degenerative scoliosis typically affects individuals over fifty. In the United States, approximately 3 million new cases of scoliosis are diagnosed annually, with a predicted increase in part due to global aging. Despite its prevalence, the etiopathogenesis of scoliosis remains unclear. MethodsThis comprehensive review analyzes the literature on the etiopathogenetic evidence for both idiopathic and adult degenerative scoliosis. PubMed and Google Scholar databases were searched for studies on the genetic factors and etiopathogenetic mechanisms of scoliosis development and progression, with the search limited to articles in English. ResultsFor idiopathic scoliosis, genetic factors are categorized into three groups: genes associated with susceptibility, disease progression, and both. We identify gene groups related to different biological processes and explore multifaceted pathogenesis of idiopathic scoliosis, including evolutionary adaptations to bipedalism and developmental and homeostatic spinal aberrations. For adult degenerative scoliosis, we segregate genetic and pathogenic evidence into categories of angiogenesis and inflammation, extracellular matrix degradation, neural associations, and hormonal influences. Finally, we compare findings in idiopathic scoliosis and adult degenerative scoliosis, discuss current limitations in scoliosis research, propose a new model for scoliosis etiopathogenesis, and highlight promising areas for future studies. ConclusionScoliosis is a complex, multifaceted disease with largely enigmatic origins and mechanisms of progression, keeping it under continuous scientific scrutiny.

Characteristics of Scoliosis in Mice Induced by Chondrocyte-specific Inactivation of L-type Amino Acid Transporter 1.

A mouse study of the Slc7a5 gene using conditional knockout to assess the effects of its inactivation on spinal deformity. This study aimed to investigate whether the mice with scoliosis [induced by chondrocyte-specific inactivation of L-type amino acid transporter 1 (LAT1)] show a developmental process similar to that of pediatric scoliosis and to examine the relationship between reduced bone mineral density (BMD) and scoliosis. Furthermore, we aimed to obtain insights into elucidating the etiology and pathophysiology of scoliosis. The etiology and pathogenesis of scoliosis are not fully understood despite substantial investigative efforts. LAT1 is an amino acid transporter that mediates the cellular uptake of large neutral amino acids. A recent study revealed that chondrocyte-specific inactivation of LAT1 in mice results in scoliosis (Col2a1-Cre;Slc7a5fl/fl mice: "Sko mice"). Body length, body weight, Cobb angle, vertebral body rotation angle, and BMD at 1, 2, 4, 6, and 8 weeks of age were examined and statistically compared with those of normal control mice. Pathologic and morphologic evaluation was performed on specimens from 10-week-old euthanized mice. The Sko mice developed thoracic scoliosis in infancy without congenital malformations. This spinal deformity progressed rapidly during growth, with diverse curve patterns and hypoplastic vertebral bodies. Pathologic examination revealed thickening of the growth plates and decreased osteoblasts, suggesting that impaired endochondral ossification was the cause of the scoliosis. Sko mice were also observed to have decreased BMD and degraded bone microstructure. Reduced BMD and bone quality may not be the causes of the onset and progression of scoliosis in the Sko mice. In Sko mice, the characteristics of scoliosis and vertebral pathology showed many similarities with syndromic scoliosis in humans. Endochondral ossification defects may impair growth, leading to scoliosis and decreased BMD.

Compensated and decompensated vertical posture of a patient with scoliosis

In 40 patients with thoracic and combined scoliosis of III and IV degrees, the loading of both legs during standing and walking was determined using Kistler dynamometric platforms. The results of the studies and analysis of posture characteristics allowed the authors to distinguish two options for compensating for the imbalance in the body that occurs during the formation of the primary curvature of the spine. A number of provisions are made regarding the pathogenesis of scoliosis, predicting the course of the disease, as well as treatment

Computed Tomographic Semiotics of Apical Vertebrae in Patients with Idiopathic Scoliosis Aged from 14 to 18 years, Depending on the Magnitude of Spinal Deformity

Idiopathic scoliosis, as many authors think, being idiopathic in terms of not fully clear etiology of the disease, due to the most complicated long-term studies, has a certain theory of the pathogenesis of scoliosis, which includes the disharmony of the longitudinal growth of the spine and spinal cord and the formation of vertebral torsion. The application of various versions of modern vertebral instrumentation for 20 years made it possible to develop a differentiated approach to the choice of surgical intervention, taking into account the patient’s age and the peculiarities of the deformed spine. Nevertheless, the use of current diagnostic methods indicated that not all the details of the deformed vertebral structure have been studied, in particular the apical ones, that are usually more changed being at the apex of the deformity. The application of multislice computed tomography (MSCT) and current statistical methods made it possible to reveal the structural features of the apical vertebrae in the group of adolescent scoliosis (14–18 years old), that is important for increasing the effectiveness of preoperative planning and improving the results of idiopathic scoliosis treatment being one of the most difficult problems of the spine surgery.

Rehabilitation of patients with early scoliosis after stage corrections of spine deformations by growing systems

Idiopathic scoliosis is a large etiological group in the structure of early scoliosis which requires the use of modern effective surgical methods for correction of deformity, in particular, using various structures with possible staged distraction (growing structures). Dysplastic changes in the musculoskeletal tissue are very important in the pathogenesis of scoliosis. Active correction of the tone of the muscular-ligamentous system of the spine in the postoperative period is of great importance in the recovery of such patients. Individual rehabilitation programs are aimed at consolidating the result of the operation (correction of the sagittal profile and normalization of the body balance), improving respiratory function, fast recovery of motor activity (in order to prevent hypostatic and thromboembolic complications), increasing self-esteem and patient satisfaction with the results of the operation. The purpose of the study is to assess the effectiveness of an integrated approach to the rehabilitation of patients with early scoliosis after correction of spinal deformities by growing systems. Materials and methods. A retrospective analysis of the results of a comprehensive rehabilitation of patients (n = 15) with idiopathic infantile scoliosis (mean age 8.6 ± 1.0 years) was performed. This group of patients was operated using a growing system with stepwise corrections using the Growing Rods, VEPTER technique. The algorithm of rehabilitation of the studied group of patients using the parameters of activity, participation, degree of dysfunction in accordance with the International classification of functioning (ICF) is presented. Evaluation of the effectiveness of the results carried out taking into account the criteria of the pain scale (VAS), verticalization time, indicators of walking, coordination, support capacity, balance of body and strength (on the CSBS platform), self-perception, psychological comfort, functions, satisfaction with the treatment. Results and discussion. In all patients, a normal sagittal profile was formed, satisfactory correction was achieved, and body balance was normalized. After a comprehensive rehabilitation course, we observed statistically significant improvements in balance, balance and load distribution, and postoperative pain was stopped. Early verticalization was successfully carried out, walking indicators reached values exceeding the conditional "norm". Assessment of coordination, support ability, balance of the body and strength on the CSBS platform showed a uniform improvement in the index of symmetry, the average value of the load on the limbs. Patients' self-perception and the level of psychological comfort before discharge were rated at 3 points, patients evaluated spinal function after surgery at 2.7 points, satisfaction with treatment was 3.5 points. Characteristics of signs of activity and participation, the degree of dysfunction within 6 months after surgery went from a score of 3-4 to a score of 0-2 (dynamic improvement). Conclusions. Correction of scoliotic spinal deformity with the help of growing systems due to improved respiration function, correction of the sagittal profile and body balance, restoration of motor activity and increased self-esteem and satisfaction with the results of the operation improves the quality of life of the patient. Due to the lack of clinical recommendations for rehabilitation in the postoperative period of patients with scoliosis (with early development), taking into account the age characteristics of this group of patients, the algorithm for their rehabilitation used in the Center shows good results in the restoration of functions and satisfaction with the treatment.

Functional Features of the Body in the Presence of Scoliosis

Important in the formation of scoliosis are violations of the supporting, spring and elastic properties of the skeleton, ligamentous and muscular system, contributing to the formation of spinal deformity. As a result, the deformation of the musculoskeletal system, which can cause various dysfunctions in the body, develops. Moreover, all forms of scoliosis are divided into two main groups-congenital and acquired. Often in the pathogenesis of scoliosis, there are two main points. The first is a violation of the growth of the vertebra due to local damage or general disorders, the second is the neurological disorders that disorganize the balancing system of muscle groups. These common disturbances can often take on the nature of irreversible. Arrested from the concave side, normal or even accelerated growth from the convex side contributes to the bending of the spine, and the premature soldering of the germ cartilage of the arches from the convex side leads to the appearance of torsion.

Differences in vertebral morphology around the apical vertebrae between neuromuscular scoliosis and idiopathic scoliosis in skeletally immature patients: a three-dimensional morphometric analysis

BackgroundRecent morphological analyses of vertebrae in patients with scoliosis have revealed three-dimensional (3D) deformities in the vertebral bodies. However, it remains controversial whether these deformities are secondary changes caused by asymmetrical vertebral loading or primary changes caused by aberrant asymmetrical vertebral growth. Furthermore, the difference in vertebral morphology between scoliosis with different pathogeneses remains unclear. This study was aimed to investigate the difference in the coronal asymmetry of vertebral bodies between neuromuscular scoliosis (NS) in Duchenne muscular dystrophy (DMD) and idiopathic scoliosis (IS) using in vivo 3D analysis.MethodsTwelve male skeletally immature patients with NS in DMD and 13 female skeletally immature patients with IS who underwent corrective fusion at our institution were included retrospectively. 3D bone models of the apical and adjacent upper and lower vertebrae in the major curve in the NS patients and in the main and compensatory curves in the IS patients were constructed using an image processing workstation. The heights of the concave and convex sides of the vertebral bodies were measured at the anterior, middle, and posterior and the concave-to-convex vertebral height ratios (VHR) were calculated.ResultsThe mean VHRs (anterior/middle/posterior) for the main curve for IS (0.897 ± 0.072/0.832 ± 0.086/0.883 ± 0.059) were significantly smaller than those for NS (0.970 ± 0.048/0.934 ± 0.081/0.958 ± 0.043) in all three parts (p < 0.001). Those of the compensatory curve in IS (0.968 ± 0.045/0.942 ± 0.067/0.967 ± 0.046) did not differ significantly from the NS values in any part.ConclusionsWhen compared to the wedging of the vertebral bodies around apical vertebrae in the major curve in NS, which was caused by asymmetric loading, the wedge deformities in both the main and compensatory curves in IS were more severe than would be expected. Our results indicated that morphometric characteristics of vertebral bodies differed according to the pathogenesis of scoliosis and that the pathology of the wedging of vertebral bodies in IS could not be a result only of asymmetric loading to the vertebral bodies.

Differential Proteome Analysis of Bone Marrow Mesenchymal Stem Cells from Adolescent Idiopathic Scoliosis Patients

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional deformity of the spine. The cause and pathogenesis of scoliosis and the accompanying generalized osteopenia remain unclear despite decades of extensive research. In this study, we utilized two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with mass spectrometry (MS) to analyze the differential proteome of bone marrow mesenchymal stem cells (BM-MSCs) from AIS patients. In total, 41 significantly altered protein spots were detected, of which 34 spots were identified by MALDI-TOF/TOF analysis and found to represent 25 distinct gene products. Among these proteins, five related to bone growth and development, including pyruvate kinase M2, annexin A2, heat shock 27 kDa protein, γ-actin, and β-actin, were found to be dysregulated and therefore selected for further validation by Western blot analysis. At the protein level, our results supported the previous hypothesis that decreased osteogenic differentiation ability of MSCs is one of the mechanisms leading to osteopenia in AIS. In summary, we analyzed the differential BM-MSCs proteome of AIS patients for the first time, which may help to elucidate the underlying molecular mechanisms of bone loss in AIS and also increase understanding of the etiology and pathogenesis of AIS.

Potential Biochemical Markers of Idiopathic Scoliosis Progression

Objective. To clarify specific signs of idiopathic scoliosis progression that may be associated with change in glycosaminoglycan turnover. Material and Methods. Blood serum samples from 180 adolescents aged 11–14 years with grade I–IV idiopathic scoliosis were tested for sulphated glycosaminoglycan levels, and for activity of lysosomal glycosidases (hyaluronidase, N-acetyl- β-D-glucosaminidase, β-glucuronidase, and α-galactosidase) and cathepsine D. Results. Reduction in serum sulfated glycosaminoglycan levels, as compared to the levels of healthy subjects, was revealed in 25 % of adolescents with early stages of spinal deformity development, and in more than 70 % of those with idiopathic scoliosis of grade III–IV. Activity of α-galactosidase in adolescents with high grade of deformity 3–10 times exceeded that of in normal subjects. Any correlation between a change in the activity of other blood lysosomal glycosidases and a degree of scoliosis was not revealed. Conclusion. The obtained data demonstrate that levels of examined sulphated glycosaminoglycans and α-galactosidase activity are in certain correlation with a grade of scoliotic deformity of the spine. Thus, these characteristics may be considered as a kind of biochemical markers of idiopathic scoliosis progression, and further study of glycosaminoglycan and galactose metabolism may be one of the prospective directions in studies of idiopathic scoliosis pathogenesis.

The role of melatonin in the pathogenesis of adolescent idiopathic scoliosis (AIS)

The cause of adolescent idiopathic scoliosis (AIS) in humans remains obscure and probably multifactorial. At present, there is no proven method or test available to identify children or adolescent at risk of developing AIS or identify which of the affected individuals are at risk of progression. Reported associations are linked in pathogenesis rather than etiologic factors. Melatonin may play a role in the pathogenesis of scoliosis (neuroendocrine hypothesis), but at present, the data available cannot clearly show the role of melatonin in producing scoliosis in humans. The data regarding human melatonin levels are mixed at best, and the melatonin deficiency as a causative factor in the etiology of scoliosis cannot be supported. It will be an important issue of future research to investigate the role of melatonin in human biology, the clinical efficacy, and safety of melatonin under different pathological situations. Research is needed to better define the role of all factors in AIS development.

Experience with lateral electric surface stimulation in the treatment of progressive idiopathic scoliosis

Due to incorrect use of nomenclature, scolioses are incorrectly classified in the paper by Altekruse and Heine. The angle measurement is inaccurate and does not correspond to Cobb's measuring method. The accuracy of the scientific statement and its value can be derived from this. The results of treatment obtained by Altekruse and Heine were improvement in or standstill of the scoliosis in 80% of the cases and progression in over 17%. This corresponds to the "Natural History of Scoliosis:" 5 to 25% of juvenile scolioses (age 3 to 10 years according to Drummont) are progressive, the figure for adolescent scolioses being lower. Therefore, electrostimulation is used to 70-80% in cases requiring no treatment, where there is no progression, in which there are no structural changes or which should be classified as malposture, in which spontaneous remission usually occurs or which remain stationary. In scolioses of over 25 degrees, with proven progression and structural changes, and possibly also with positive family history, electrostimulation fails. As in almost all papers published to date, Altekruse and Heine's paper disregards the behavior of the sagittal curvature of the spine under electrostimulation. We demonstrate in two cases that electrostimulation can have a considerable pathologic effect, causing lordosis. Since, on the basis of recently adopted opinions, there is reason to believe that there is a causal connection between lordosis and the pathogenesis of scoliosis, it must be assumed that in such cases electrostimulation incites or aggravates the development of scoliosis or is at least potentially capable of doing so. At any rate, in the two cases in which it was demonstrated that electrostimulation caused lordosis, the scoliosis was significantly aggravated, so that in these cases at least it must be assumed that the method has a health-damaging effect. Electrostimulation is a cost factor which does not seem justifiable today, with economy an obligation. The cost of using it in a mere 100 cases would be sufficient to pay for proper screening of all the children in one school year in the Federal Republic. Children who are really at risk could be given effective treatment. In Sweden, this has resulted in 60% of the scoliosis operations previously required in populations of the same size no longer being necessary.

Melatonin the "light of night" in human biology and adolescent idiopathic scoliosis.

Melatonin "the light of night" is secreted from the pineal gland principally at night. The hormone is involved in sleep regulation, as well as in a number of other cyclical bodily activities and circadian rhythm in humans. Melatonin is exclusively involved in signalling the 'time of day' and 'time of year' (hence considered to help both clock and calendar functions) to all tissues and is thus considered to be the body's chronological pacemaker or 'Zeitgeber'.The last decades melatonin has been used as a therapeutic chemical in a large spectrum of diseases, mainly in sleep disturbances and tumours and may play a role in the biologic regulation of mood, affective disorders, cardiovascular system, reproduction and aging. There are few papers regarding melatonin and its role in adolescent idiopathic scoliosis (AIS). Melatonin may play a role in the pathogenesis of scoliosis (neuroendocrine hypothesis) but at present, the data available cannot clearly support this hypothesis. Uncertainties and doubts still surround the role of melatonin in human physiology and pathophysiology and future research is needed.

Changes in Melatonin Receptors in Relation to the Development of Scoliosis in Pinealectomized Chickens

The 2[125I]iodomelatonin binding assay was used to investigate the involvement of melatonin receptors in the development of scoliosis in pinealectomized chickens. To compare the binding properties of melatonin receptors in the thoracic spinal cord between pinealectomized chickens that had scoliosis develop and those that did not. Surgical pinealectomy in young chickens induced scoliosis with a reported incidence of 50% to 100%. The factors regulating the development of scoliosis in this animal model are unclear. Melatonin receptors have been shown in the spinal cord of chickens, but their functions are still unknown. This study addresses the question as to whether spinal cord melatonin receptors are related to the pathogenesis of scoliosis in pinealectomized chickens. Control and pinealectomized chickens were kept under controlled lighting conditions and monitored for scoliosis development. At 9-11 weeks after pinealectomy, thoracic spinal cords were removed for 2[125I]iodomelatonin binding assay, and blood was collected for serum melatonin assay at either the middle of the light period or middle of the dark period. Pinealectomy in young chickens produced: (1) loss of diurnal variations in serum melatonin levels, (2) 50% incidence of scoliosis, and (3) attenuation in the diurnal variations in the receptor affinity to melatonin. No differences were detected in the serum melatonin levels or binding of spinal cord melatonin receptors between the pinealectomized chickens that had scoliosis develop and those that did not. Changes are detected in melatonin receptor binding after pinealectomy. However, these changes cannot account for the reason why scoliosis develops in some chickens after pinealectomy, while it does not in others. Neither low melatonin serum level nor changes in spinal cord melatonin binding can be a sole etiologic factor in the pathogenesis of scoliosis in pinealectomized chickens.

Prevalence of Scoliosis in (3-Thalassemia

The objective of this study was to determine the prevalence and possible pathogenesis of scoliosis in beta-thalassemia in our country, and to compare its characteristics to those of patients with idiopathic scoliosis from the same geographic area. Twenty-four [13 male and 11 female thalassemic patients aged 16 +/- 7 years (range 7-32 years)] of 115 examined patients with beta-thalassemia showed scoliosis of 14 degrees +/- 11 (range 10-65 degrees) radiologically. The prevalence of scoliosis in the thalassemic population was 21% in this series, whereas the overall prevalence of scoliosis in the general Greek population was 6% (Smyrnis PN, Valavanis J, Alexopoulos A, Siderakis G, Giannestras NJ: School screening for scoliosis in Athens, J Bone Joint Surg 61B:215-217, 1979). The scoliosis prevalence in the general population was significantly higher in the females (5%) than in the males (1%), whereas no difference in prevalence was found between the two sexes in the thalassemic population. The most common curve pattern in thalassemia was the left lumbar (38%) followed by the right lumbar (21%), whereas in patients with idiopathic scoliosis the left thoracolumbar most commonly appeared (25%) followed by the left lumbar (14%). No patient with thalassemia showed radiographic signs of congenital spinal deformities and spinal fractures, whereas all patients showed a significant retardation of their skeletal maturation. The age of the thalassemic patients with scoliosis was significantly (p = 0.0003) higher than in patients without scoliosis. The hematocrit of the thalassemic patients with scoliosis was significantly (p = 0.0012) lower than in those without scoliosis, whereas the rate of transfusions was not correlated with the magnitude of the scoliosis. The level of ferritin was significantly (p = 0.025) higher in the thalassemic patients with scoliosis than in those without scoliosis. The duration of Desferal treatment was significantly (p = 0.0357) longer in thalassemic patients with scoliosis when compared with those without scoliosis. Thus, the prevalence, curve pattern, and etiology of scoliosis in beta-thalassemia differ from those of idiopathic scoliosis, indicating that the spinal deformities in thalassemia represent a distinct type of scoliosis.

Muscle Fiber Types in Thoracic Erector Spinae Muscles

Histochemical studies of the thoracic part of the erector spinae muscles in scoliosis have shown a consistently higher proportion of Type 1 fibers on the convex side. The fiber distribution of the multifidus and semispinalis muscles was studied in adolescent idiopathic scoliosis (AIS). Compared with sex- and age-matched controls, a "normal" percentage of Type 1 fibers was found on the convex right side and significantly smaller percentage of Type 1 fibers on the concave side. Boys with AIS showed the same pattern as girls. In two patients with double major curves, the same pattern could be seen on the convexity of both curves. Patients with congenital scoliosis or scoliosis with early onset showed a different pattern with a "normal" percentage of Type 1 fibers on the concave side but a significantly greater percentage of Type 1 fibers on the convex side. In AIS, the deviation in the fiber distribution may constitute a primary factor in the pathogenesis of scoliosis. In congenital scoliosis the differences in fiber distribution between the convex and concave sides are considered secondary in the pathogenesis of the spinal curvature.

Postural control in scoliosis. A statokinesimetric study in patients with scoliosis due to neuromuscular disorders and in patients with idiopathic scoliosis.

Statokinesimetric characteristics were analysed in patients with scoliosis which had developed in the course of degenerative neuromuscular disorders and in patients with adolescent idiopathic scoliosis. Patients with Duchenne and limb- girdle muscular dystrophy and spinal muscular atrophy showed markedly decreased oscillations of the body's centre of gravity, in addition to a forward shift of its mean position. Thus the postural equilibrium in neuromuscular patients with scoliosis is even more efficiently controlled than normal. On the other hand, patients with idiopathic scoliosis did not show any significant changes as compared with normal subjects. The present study therefore does not support the suggestion that the pathogenesis of scoliosis, at least in neuromuscular patients, is triggered by an impairment of descending postural control.

Pathogenesis of Scoliosis

Scoliosis often occurs in otherwise normal individuals or it may be associated with many widely differing diseases. The curve patterns are fairly uniform and the vertebrae always rotate in the frontal and horizontal planes producing convex side rotation with little displacement of the spinuous processes. Many small curves do not increase. Progressive scoliosis increases linearly and the rate of increase accelerates at puberty. No endocrine abnormalities have been observed in these patients. Usually the deformity is not caused by abnormal vertebral growth nor by abnormal collagen in verterbral ligaments. The glycosaminoglycans of nucleus pulposus are decreased in patients with idiopathic scoliosis. We speculate that loss of proteoglycans will affect the viscoelastic properties of the intervertebral discs which may result in permanent deformation. The etiology of scoliosis appears to be multifactorial with a genetic tendency to the deformity which is triggered in different individuals by different factors, some medical, some mechanical and some genetic.

Familial posterior column ataxia (Biemond's) with scoliosis.

A family of six siblings, of which three members showed clinical signs of ataxia due to posterior column involvement, is reported. Scoliosis was a prominent feature in the affected members. One sibling showed posterior column ataxia without scoliosis. The pathogenesis of scoliosis in this condition is discussed.

Spontaneous Occurrence of Scoliosis in the Chicken

Deformities of the spine have been attributed to a variety of causes: inappropriate diet and lack of exercise (5), inadequate breeding (1), and intense inbreeding (3). Scoliosis has occurred in chicks produced from embryos injected with insulin (8). More recently, a genetic mechanism has been considered to be the significant factor (9). Scoliosis was recently observed in 30% of a group of white Pekin ducks 40 days old and older (17). Segments of were frequently present in the vertebrae and the interarticular spaces. Persistence of segments of the was considered to be a significant factor in the pathogenesis of scoliosis in these ducks. A persistent notochord has been observed very rarely in

Treatment of Scoliosis

We do not know the etiology of the great majority of cases of structural scoliosis with which we are confronted today, namely, the 80 to 90 per cent classified as “idiopathic.” Treatment of these cases, once the lateral curvature has developed, must be directed by one knowledgeable in the pathogenesis of scoliosis, the potentialities of these curves in terms of etiology and degree of maturation of the individual, and an awareness of the various methods of treatment. The basic principles of obtaining correction are distraction and the application of corrective forces to the convex side of the curve, by external or internal fixation. Ironically, while our present-day methods are somewhat more refined and sophisticated, these are the same principles that have been utilized since the fifteenth century. We have in the past fifty years added the innovation of fusion of the vertebral segments involved, to maintain the correction that has been attained. Needless to say, we are striving through basic and clinical research to ascertain the cause of idiopathic scoliosis and, at the same time, evolving better methods of efficient and effective correction, and maintaining correction of these deformities, once they have developed.