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Topic |
Findings |
Authors |
| Genetic temporal fault
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3 gradients are set up in embryogenesis (dorsoventral, craniocaudal and left-right) these gradients are wavelike (Bard) rather than continuous stream of some morphogenesis (Roth). | Bard J. Morphogenesis: The cellular and molecular processes of developmental anatomy. Cambridge: Cambridge University press. 1990: 164-72.Roth S, Stein D, Nusslein-Vollhard C. A gradient of nuclear localization of protein determines dorsoventral pattern in the Drosophila embryo. Cell 1989;59: 1189-202. |
| The program itself is written in the DNA and managed by the master control genes of the Homeobox sequences, whose effect is trigger cascades of downstream genes resulting in differentiation and development. | DeRobertis EM, Oliver G, Wright CVE. Homeobox genes and the vertebrate body plan. Sci Am 1990; Juliy: 46-52.De Robertis EM, Morita EA, Cho KW. Gradient fields and Homeobox genes [Review]. Development 1991; 112:669.
Kauffman SA. The origin of Order. Oxford: Oxford University Press 1993:407-642. |
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| The local and global timing of growth related enzyme-driven processes are the cause of morphogenesis.The precise nature of the deformity results from timing and severity of the insult.
Once established, the natural history of the deformity is determined by factors common to all etiologies, eg, the child’s maturity, growth rate, buffering of the genome, and whether the insult continues. |
Steven PS. Patterns in Nature. Middlesex, England: Penguin Books Ltd 1974. | |
| This developmental program can be destabilized by developmental instability. | Adams MS, Niswander JD. Developmental ‘noise’ and a congenital malformation. Genet Res Camb 1967; 10:313-7.Van Valen L. A study of fluctuating asymmetry. Evolution 1962; 16:125-42.
Waddington CH. The strategy of genes. London: Allen & Unwin 1957. |
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| Symmetry is lost when the developmental program coded in the genome, master by the control of the Homeobox sequence, fails to run optimally. | Goldberg CJ, Fogarty EE, Moore DP, Dowling FE. Scoliosis and developmental theory: adolescent idiopathic scoliosis. Spine. 1997 Oct 1; 22(19):2228-37; discussion 2237-8. | |
| Underlying all morphology is the individual’s genetic design, which is achieved by the expression of particular genes in a controlled and timed sequence, analogous to a complex and self-monitoring computer program. The running of this program, the genotype, depends on the circumstance met during development, ie, physiologic stress. | Adams MS, Niswander JD. Developmental ‘noise’ and a congenital malformation. Genet Res Camb 1967; 10:313-7.Van Valen L. A study of fluctuating asymmetry. Evolution 1962; 16:125-42.
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| The extent to which the final phenotype expresses the genotype depends on the ability of that genotype to withstand intercurrent stress factors (intrinsically genetic) and the timing and severity of those stresses (intrinsically environmental).The result is the inextricable combination of genetic endowment and environment.
Developmental instability can underpin the understanding of all varieties of scoliosis without the need for a separate disease process to explain each one. |
Goldberg CJ, Fogarty EE, Moore DP, Dowling FE. Scoliosis and developmental theory: adolescent idiopathic scoliosis. Spine. 1997 Oct 1; 22(19):2228-37; discussion 2237-8. | |
| A lateral curvature of the spine-‘scoliosis’-can develop in association with postural imbalance due to genetic defects | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment. Scoliosis. 2006 Mar 31; 1(1):3. | |
| Lateral spinal curvature results in asymmetric loading which, in turn, affects gene expression underlying the structure and function of growth plates within the spine. | Antaniou J, Arlet V, Goswami T, Aebi M, Alini M: Elevated synthetic activity in the convex side of scoliotic intervertebral discs and endplates compared with normal tissues. Spine 2001, 26:E198-E206.Chen B, Fellenberg J, Wang H, Carstens C, Richter W: Occurrence and regional distribution of apoptosis in scoliotic discs. Spine 2005, 30:519-524.
Kluba T, Niemeyer T, Gaissmaier C, Grunder T: Human annulus fibrosis and nucleus pulpous cells of the intervertebral disc – Effect of degeneration and culture system on cell phenotype. Spine 2005, 30:2743-2748. Shea KG, Ford T, Bloebaum RD, D’Astous J, King H: A comparison of the microarchitectural bone adaptations of the concave and convex thoracic spinal facets in IS. J Bone Joint Surg 2004, 86-A:1000-1006. Urban MR, Fairbank JCT, Bibby SRS, Urban JPG: Intervertebral disc composition in neuromuscular scoliosis. Changes in cell density and glycosaminoglycan concentration at the curve apex. Spine 2001, 26:610-617. Villemure I, Aubin CE, Grimard G, Dansereau J, Labelle H: Progression of vertebral and spinal 3-D deformities in AIS. A longitudinal study. Spine 2001, 26:2244-2250. Villemure I, Chung MA, Seck CS, Kimm MH, Matyas JR, Duncan NA: The effects of mechanical loading on the mRNA expression of growth-plate cells. Research into Spinal Deformities 2002, 4:114-118.
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| Structural scoliosis, in contrast, is seen as a genetically based disorder whose outcome largely is impervious to environmental influences (Keim HA, 1987). | Keim HA: The Adolescent Spine. 2nd edition. Springer-Verlag, New York, Heidelberg, Berlin; 1987. | |
| This paper concludes that the vertebral growth modulation mechanism can explain curve progression of about 2 degrees (Cobb) per year over six years.
This suggests that there are other mechanisms (possibly non-mechanical) that contribute to curve progression in cases of more rapid curve progression |
Stokes IA, Burwell RG, Dangerfield PH. Biomechanical spinal growth modulation and progressive adolescent scoliosis – a test of the ‘vicious cycle’ pathogenetic hypothesis: Summary of an electronic focus group debate of the IBSE. Scoliosis. 2006 Oct 18; 1:16. | |
| The genetic basis of vertebral deformation has been attributed to the homeobox genes. | Akam M, Dawson I, Tear G. Homeotic genes and the control of segment diversity. Development 1988; 104: 123-33.Berry CLW. What’s in a homeobox. The development of pattern during embryonic growth [editorial]. Virchoes Arch A Pathol. Anat. Histopathol, 1992; 420: 291-4.
Graham JH, Freemen C, Emlen JM. Antisymmetry, directional asymmetry, and dynamic morphogenis. Genetica 1993; 89: 121-37. |
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| Vertebral growth
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The results from this study demonstrate that dynamic loading of the vertebrae provides the greatest growth modulation potential. | Akyuz E, Braun JT, Brown NA, Bachus KN. Static versus dynamic loading in the mechanical modulation of vertebral growth. Spine. 2006 Dec 1; 31(25):E952-8. |
| The results have implications in the prevention of intervertebral disc degeneration, suggesting that loading conditions may be optimized to promote maintenance of normal structure and function. | Walsh AJ, Lotz JC. Biological response of the intervertebral disc to dynamic loading. J Biomech. 2004 Mar; 37(3):329-37. | |
| These findings indicate that sustained compression loading suppressed growth more than intermittent loading at both anatomical locations. | Stokes IA, Gwadera J, Dimock A, Farnum CE, Aronsson DD. Modulation of vertebral and tibial growth by compression loading: diurnal versus full-time loading. J Orthop Res. 2005 Jan; 23(1):188-95. | |
| Thus, the vicious cycle defines a paradigm in which fixed asymmetric spinal loading is cause AND effect, and explains why the danger of progression is so high in patients during periods of rapid growth: asymmetric loading actually inhibits growth within affected spinal elements. | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment.Scoliosis. 2006 Mar 31; 1(1):3. | |
| The control mechanism for growth plate regulation is not known but there is evidence to suggest that hormonal factors do influence progression of scoliotic curves . | Kasperk CJA, Fitzsimmons R, Strong DDV, Mohan SLD BD, Jennings JC, Wergedal JTH AN, Baylink DRM GR. Studies of the mechanism by which androgens enhance mitogenesis and differentiation in bone cells. J. Clin. Endocrinol Metab 1990; 71: 1322-9. | |
| Vertebral wedging\ Localize deformation
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This pattern of primary 3D deformities on one vertebra plus half of the vertebrae above and half of the one below is typical in both chicken and human idiopathic scoliosis curve development. The rest of the vertebrae are disorientated but not deformed.The localized bone deformity starts as a delay of ossification in the posterior-lateral part of one vertebra, which produces a tilt of the overlaying vertebra.
When the bone deformity is large, there are significant limitations to conservative treatment. In such cases, curves will be very stiff and have a bad prognosis. Laying x-rays (supine/prone) can be very helpful in determining the flexibility and therefore the extent of bone deformity in an individual case. Clearly, in both cases, the deformities are 3-dimensional demonstrating: i) Lateral wedging ii) Anterior/Posterior wedging iii) Rotational deformity prescribing an arc from the spinous process through the vertebral body
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Coillard C, Rivard CH. Vertebral deformities and scoliosis. European Spinal Journal 1996; 5(2):91-100. |
| Idiopathic scoliosis is a complex multifactoral neuromuscular skeletal disorder, growth disharmony resulting in localized vertebral deformity is the initiating factor as well as a significant but not the only progression factor | Coillard C, Rivard C H. Etiology of idiopathic scoliosis : an unsynchronized growth or why a system can turn chaotic. European Spinal Resonnances, 2001; 29; 1123- 1146. | |
| This suggests that, at adolescence, developmental instability may result in a loss of symmetry in growth, and that in the presence of an increased developmental left-right gradient, this may be of sufficient severity to be classified as deformity and come to the attention of orthopaedic surgeons. | Goldberg CJ, Dowling FE, Fogarty EE, Moore DP. Adolescent idiopathic scoliosis as developmental instability. Genetica. 1995; 96(3):247-55. | |
| These arguments (…) do permit the possibility that the vertebral changes in scoliosis are themselves the primary deformity: that the spine in scoliosis is crooked because the constituent vertebrae have a morphology closer to the individual steps of a spinal staircase than to a column of wooden blocks. | Galloway JW. Macromolecular asymmetry. In: Bock GR, Mars J, eds. Ciba Foundation Symposium: Biological Asymmetry and handedness. Chichester, United Kingdom: John Wiley & Sons, 1991:16-35.Somerville EW. Rotational lordosis: The development of the single curve. J Bone Joint Surg [Br] 1952; 34: 421-7. | |
| Vertebra might have an ordered left-right asymmetry (Milles, Farkas) and this may become regular (Goldberg). | Miles M. Lateral vertebral dimensions and lateral spinal curvature. Human Biol. 1944; 16:153-71.Farkas A. Physiologic scoliosis. J Bone Joint Surg. 1942; 23: 607-21.
Goldberg CJ, Fogarty EE, Moore DP, Dowling FE. Scoliosis and developmental theory: adolescent idiopathic scoliosis. Spine. 1997 Oct 1; 22(19):2228-37; discussion 2237-8. |
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| When the patient is radiographed while bending to the side, lying on his back (supine), or unconscious, the curvature is always present, even though its magnitude is reduced from that in a standing position. At this point in the development of scoliosis, a structural spinal deformity is judged to be present. | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment.Scoliosis. 2006 Mar 31; 1(1):3. | |
| Central to the transformation of a reversible spinal curvature into a structural spinal deformity, irrespective of the factor(s) that trigger its development, is a characteristic wedge-shaped deformity of the vertebral bodies that appears early in the disease process. | Xiong B, Sevastik JA, Hedlund R, Sevastik B: Radiographic changes at the coronal plane in early scoliosis. Spine 1994, 19:159-74.
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| The results revealed that vertebral wedging was consistent among the population, occurred mainly at the apex of thoracic curves and was primarily in the coronal plane. There was no deformity in the sagital plane. This uniformity of structural transformation would be the expected result if progression among all individuals resulted from discrepancy in growth at the vertebral plates, due to unequal side-to-side loading. | Parent S, Labelle H, Skalli W, Latimer B, de Guise J: Morphometric analysis of anatomic scoliotic specimens. Spine 2002, 27:2305-2311. | |
| Using a different approach, Villemure et al., (2001) found a similar pattern of deformity. Among 28 adolescents whose deformities were measured over time, as they developed, there was a consistent pattern for lateral wedging of vertebral elements as would be predicted if their evolution shared a common mechanism. | Villemure I, Aubin CE, Grimard G, Dansereau J, Labelle H: Progression of vertebral and spinal 3-D deformities in AIS. A longitudinal study. Spine 2001, 26:2244-2250 | |
| This vertebral deformity sets the stage for a ‘vicious cycle’ of curvature progression and symptom development. | Roaf R: Vertebral growth and its mechanical control. J Bone Joint Surg 1960, 42B:40.Stokes IAF: Hueter-Volkmann Effect. Spine: State of the Art Reviews 2000, 14:349-357. | |
| Once a curvature develops, unequal compression on vertebral plates results in unequal growth, which in turn contributes to the progression of the deformity. Asymmetrical changes in rib and vertebral structure and function predictably follow from the asymmetric stresses applied in a spinal curvature. | Andriacchi T, Schultz AB, Belytschko T, Galante J: A model for studies of mechanical interactions between the human spine and rib cage. J Biomech 1974, 7:497-507.Aubin CE, Dansereau J, deGuise JA, Labelle H: Rib cage-spine coupling patterns involved in brace treatment of AIS. Spine 1997, 22:629-635. | |
| Unrelieved contrasting forces on each of the two sides of a vertebral growth plate, however, quickly produce within vertebrae and intervertebral discs a wedged deformity whose magnitude can account for most if not all of the lateral curvature that develops in a progressive scoliosis. | Mente PL, Aronsson DD, Stokes IAF, Iatridis JC: Mechanical modulation of growth for the correction of vertebral wedge deformities. J Orthop Res 1999, 17:518-524.Mente PL, Stokes IAF, Spence H, Aronsson DD: Progression of vertebral wedging in an asymmetrically loaded rat tail model. Spine 1997, 22:1292-1296.
Stokes IAF, Gardner-Morse MG: Muscle activation strategies and spinal loading in the lumbar spine with scoliosis. Spine 2004, 29:2103-2107. Stokes IAD, Spence H, Aronsson DD, Kilmer N: Mechanical modulation of vertebral body growth. Implications for scoliosis progression. Spine 1996, 21:1162-1167. |
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| Certainly, if biomechanical factors do explain the evolution of a scoliosis in the frontal plane, then biomechanics might also explain the associated rotational asymmetry that normally correlates with the frontal plane curvature. | Stokes IA, Burwell RG, Dangerfield PH. Biomechanical spinal growth modulation and progressive adolescent scoliosis-a test of the ‘vicious cycle’ pathogenetic hypothesis: Summary of an electronic focus group debate of the IBSE. Scoliosis. 2006 Oct 18; 1:16. | |
| Cell death was highest within cells at the apex of the curvature, where mechanical loading is highest, and was similar for all age groups and for subjects with neuromuscular or idiopathic scoliosis. This result suggests that the observed changes occurred via a common pathway for pathogenesis despite divergent histories, stages of growth, and triggers for initiation of scoliosis. It is reasonable to predict that the activation of programmed cell death in response to mechanical loading comprises the molecular mechanism by which a reversible spinal curvature is converted into an irreversible spinal deformity. | Chen B, Fellenberg J, Wang H, Carstens C, Richter W: Occurrence and regional distribution of apoptosis in scoliotic discs. Spine 2005, 30:519-524. | |
| This study shows that vertebrae, when asymmetrically loaded, become wedged. This is consistent with the concept of mechanically provoked progression of scoliotic deformities according to the Hueter-Volkmann law. | Mente PL, Stokes IA, Spence H, Aronsson DD. Progression of vertebral wedging in an asymmetrically loaded rat tail model. Spine. 1997 Jun 15; 22(12):1292-6. | |
| Postural deformity associated with the spinal deformity | The posture and movement in scoliotic patients is never normal. Part of the research project involved studying the kinametrics of the spine and posture in scoliotic patients.The amplitude of movement in opposite directions for scoliotic patients is not surprisingly unbalanced.
Studies using Vicom Motion analysis reveal very specific postural abnormalities relating to each type of curve. True importance of combined curve and postural classification. |
Nguyen VH, Leroux MA, Badeaux J, Zabjek K, Coillard C, Rivard CH.Classification des scolioses thoraco-lombaires gauches selon leur morphologie radiologique et leur géométrie posturale. Annales de chirurgie 1998; 52(8):752-760.De la Huerta F, Leroux MA, Zabjek KF, Coillard C, Rivard CH. Évaluation stéréovidéographique de la géométrie posturale du sujet sain et scoliotique. Annales de chirurgie 1998; 52(8): 776-783. |
| A lateral curvature of the spine-‘scoliosis’-can develop in association with postural imbalance due to genetic defects | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment.Scoliosis. 2006 Mar 31; 1(1):3. | |
| Treatment principle\ Corrective movement\ Global postural changes
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Dynamic Corrective Bracing has four modes of action. i) Dynamic opening of curves: Changes in the compression and tensile loading of the vertebral growth plates can limit, stabilise or even reverse the vertebral deformity, one of the major progression factors in idiopathic scoliosis. Research has shown that dynamic reduction of Cobb angles (alternative compression and tension on growth plates) during growth has a greater effect in arresting or reversing progression than static Cobb reduction. ii) Normalisation of postural disorganisation by globally and dynamically over-correcting the posture. iii)Neuromuscular re-education: A specific new movement strategy is repeatedly performed by the patient through normal activities of daily living, whilst wearing the brace. This provides progressive improvement of posture and Cobb angles over time within the limits of the patient’s level of skeletal maturing and deformity. iv) Neuromuscular integration: Over time the new movement strategy becomes integrated into the brain overwriting the previous abnormal posture. The corrective movements resultant new posture and Cobb angles are maintained post bracing with no loss of correction over time. | Coillard C, Rivard C H. Etiology of idiopathic scoliosis : an unsynchronized growth or why a system can turn chaotic. European Spinal Resonnances 2001; 29; 1123- 1146.
Bernick S, Cailliet R. Vertebral end-plate changes with aging of humain vertebrae. Spine 1982; 7: 87-102. |
| Structural curvature: Before skeletal maturity. Ultimately, under the constant stress of asymmetric loading, there is a predictable change in skeletal architecture (triangle), and the curvature evolves into a spinal deformity which no longer is flexible and readily reversible. Once this occurs, there is a fixed asymmetric deformity of the torso that does not resolve when the patient adjusts his posture. Once the curvature has progressed into a structural deformity, it still can be mild, nondeforming, and of little threat to the person’s health and well-being. However, the vicious cycle model predicts that the continuous asymmetric load, however small, will push it in the direction of progression unless steps are taken to counteract it. The more asymmetric the load, the likelier it is that the curvature will progress. Yet,even with severe structural deformities the curvature can be reversed if the state of continuous loading is reversed and symmetrical pressure on the growth plates is restored. | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment. Scoliosis. 2006 Mar 31; 1(1):3. | |
| Structural curvature: After skeletal maturity. Once bone growth is complete, vertebral deformities persist for life. However, despite the structural deformity at the apex of the curvature, other parts of the spine remain flexible and can still correct on side bending.Thus, a curvature measuring 50 degrees in the standing position may correct to 30 degrees in the supine position. This 20-degree ‘functional’ component of the curvature can still be corrected by a change in posture, but the overall flexibility of the spine decreases with age. | Deviren V, Berven S, Kleinstueck F, et al.: Predictors of flexibility and pain patterns in thoracolumbar and lumbar IS. Spine 2002, 27:2346-2349.
Shands AR, Barr JS, Colonna PC, Noall L: End-result study of the treatment of idiopathic scoliosis: Report of the research committee of the American Orthopedic Association. J Bone Joint Surg 1941, 23:963-977. |
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| The findings indicate that in self-selected postures the gravitational effect of leaning and the muscle activity in paraspinal muscles may serve to reduce the apex angle. Thus, a fully upright, centered posture may not be best for correction of every patient’s spinal curve. | Gram MC, Hasan Z. The spinal curve in standing and sitting postures in children with idiopathic scoliosis. Spine. 1999 Jan 15; 24(2):169-77. | |
| When the load asymmetry is removed while significant growth potential remains, progression stops; when the asymmetry of the vertebral column is reversed and the unbalanced loading is thereby corrected, complete resolution of deformity occurs.Reversing the asymmetric loading by restoring normal posture and movement therefore allows even severe structural curvatures to resolve completely. | Harrington P: Is scoliosis reversible? In vivo observations of reversible morphological changes in the production of scoliosis in mice. Clin Orthop and Rel Res 1976, 116:103-111. | |
| Recent studies support the longstanding hypothesis that spinal deformity results directly from such postural imbalance, irrespective of the primary trigger, because the dynamics of growth within vertebrae are altered by continuous asymmetric mechanical loading.These data suggest that, as long as growth potential remains, evolution of a spinal curvature into a spinal deformity can be prevented by reversing the state of continuous asymmetric loading.
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Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment. Scoliosis. 2006 Mar 31; 1(1):3. | |
| Research to define patient-specific mechanics of spinal loading may allow quantification of a critical threshold at which curvature establishment and progression become inevitable, and thereby yield strategies to prevent development of spinal deformity. In fact I would argue that no matter what you believe to be the cause of AIS, ultimately the problem can be reduced to the production of an imbalance of forces along the spine 1. | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment. Scoliosis. 2006 Mar 31; 1(1):3. | |
| Even after a spinal curvature has evolved into a spinal deformity, it may still be reversed if the postural asymmetry is removed while significant growth potential remains.Harrington (1976) reported that severe structural curvatures induced by postural asymmetry in mouse resolved completely when the postural imbalance was removed. | Harrington P: Is scoliosis reversible? In vivo observations of reversible morphological changes in the production of scoliosis in mice. Clin Orthop and Rel Res 1976, 116:103-111. | |
| Differences in progression among individual patients may stem from divergence in muscle activation strategies rather than an inherent deficiency in structure and function within the spine (Stokes).Such differences in muscle activation strategies might also explain the observation that simple ‘side shift’ exercises were correlated with curvature stabilization in two groups of patients at high risk of progression, by transient repeated reversal of asymmetric loading. | Stokes IAF, Gardner-Morse MG: Muscle activation strategies and spinal loading in the lumbar spine with scoliosis. Spine 2004, 29:2103-2107.Maruyama T, Kitagawa T, Takeshita K, Mochizuki K, Nakamura K:Conservative treatment for AIS: can it reduce the incidence of surgical treatment? Pediatric Rehabilitation 2003, 6:215-219.
Mehta MH: Active auto-correction for early adolescent idiopathic scoliosis. J Bone Joint Surgery 1986, 68:682. |
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| Exercises, designed to interrupt steady state spinal loading at the apex of the curvature, can be predicted to forestall the cascade of molecular events that transform benign spinal curvatures into progressive spinal deformities. | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment. Scoliosis. 2006 Mar 31; 1(1):3. | |
| Our simulations using a model that represents the lumbar spinal musculature and a spine with increasing degrees of spinal curvature suggests that there is a range of muscle activation strategies that may predispose to progression by the ‘vicious cycle’ mechanism, but other strategies can load the spine uniformly, or even reverse the asymmetrical loading that would lead to progressive deformity. | Stokes I, Gardner-Morse M. The role of muscles and effects of load on growth. Stud Health Technol Inform. 2002; 91:314-7. | |
| These concepts need evaluation in relation to (1) the etiopathogenesis of IS and (2) a possible new treatment approach to idiopathic scoliosis involving a neuromorphic device to control the output for muscle stimulators. | Burwell RG, Dangerfield PH. Etiologic theories of idiopathic scoliosis: neurodevelopmental concepts to be evaluated. Stud Health Technol Inform. 2002; 91:15-9. | |
| Dr. Stokes illustrates the importance of neuromuscular action in the bone growth modulation process so underlying both the roles of muscle strength and CNS motor control strategies as often claimed in conservative treatment. Hypothetically, rehabilitation programs that would alter the muscle forces and hence the spinal loading over a substantial proportion of the time could alter the growth modulation effect. I speculate that this would require asymmetric muscle hypertrophy and strengthening, and/or development of new neuromuscular activation patterns. Alternatively, a brace that holds the spine in a less curved posture might result in less asymmetrically loaded spine. | Stokes IA, Burwell RG, Dangerfield PH. Biomechanical spinal growth modulation and progressive adolescent scoliosis – a test of the ‘vicious cycle’ pathogenetic hypothesis: Summary of an electronic focus group debate of the IBSE. Scoliosis. 2006 Oct 18; 1:16. | |
| I would certainly encourage clinicians to design therapeutic approaches to exploit these biomechanical explanations of scoliosis progression in treatment of small curves. One might aim either to modify the vertebral growth asymmetrically, or to modify the forces acting on the spinal column and endplate physes – both subject to the presence of sufficient residual growth. | Stokes IA, Burwell RG, Dangerfield PH. Biomechanical spinal growth modulation and progressive adolescent scoliosis – a test of the ‘vicious cycle’ pathogenetic hypothesis: Summary of an electronic focus group debate of the IBSE. Scoliosis. 2006 Oct 18; 1:16. | |
| Schroth’s technique positively influenced the Cobb angle, vital capacity, strength and postural defects in outpatient adolescents. The Schroth technique recognizes and treats scoliosis as a 3-dimensional problem, and patients with scoliosis are instructed in postural and breathing exercises designed to help with back flexibility, restore posture and balance, and reduce the effect gravity has on the spine. Treatment according to the individual curve pattern, with and without special exercises to elongate and derotate trunk and spine. however, the Schroth method alone is not necessarily an answer. “The physiotherapy in general and the Schroth technique in particular cannot be taken as a treatment in competition with other treatments,” “It can be also used in combination with a brace as well as pre-surgically.” The best results for the treatment are realized when the therapy is used in conjunction with other treatments, studies show. | Otman S, Kose N, Yakut Y. The efficacy of Schroth s 3-dimensional exercise therapy in the treatment of adolescent idiopathic scoliosis in Turkey. Saudi Med J. 2005 Sep; 26(9):1429-35. | |
| Importance of an early intervention in order to correct the bony deformation | Importance of an early intervention (before 30degrees) to prevent any progression. | Durand H, Salanova C. Brace treatment of adolescent idiopathic scoliosis, results in 477 patients. Doctoral thesis. 1991. University of Toulouse, FranceCoillard C, Leroux MA, Zabjek KF, Rivard CH. SpineCor – a non-rigid brace for the treatment of idiopathic scoliosis: post-treatment results. Eur Spine J 2003; 12: p. 141-148
Lonstein JE, Carlson JM. The prediction of curve progression in untreated idiopathic scoliosis during growth. J Bone Joint Surg 1984; 66A: 1061-1071 |
| Even after a spinal curvature has evolved into a spinal deformity, it may still be reversed if the postural asymmetry is removed while significant growth potential remains.Harrington (1976) reported that severe structural curvatures induced by postural asymmetry in mouse resolved completely when the postural imbalance was removed. | Harrington P: Is scoliosis reversible? In vivo observations of reversible morphological changes in the production of scoliosis in mice. Clin Orthop and Rel Res 1976, 116:103-111. | |
| Recent studies support the longstanding hypothesis that spinal deformity results directly from such postural imbalance, irrespective of the primary trigger, because the dynamics of growth within vertebrae are altered by continuous asymmetric mechanical loading. These data suggest that, as long as growth potential remains, evolution of a spinal curvature into a spinal deformity can be prevented by reversing the state of continuous asymmetric loading. | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment. Scoliosis. 2006 Mar 31; 1(1):3. | |
| When the load asymmetry is removed while significant growth potential remains, progression stops; when the asymmetry of the vertebral column is reversed and the unbalanced loading is thereby corrected, complete resolution of deformity occurs. Reversing the asymmetric loading by restoring normal posture and movement therefore allows even severe structural curvatures to resolve completely. | Harrington P: Is scoliosis reversible? In vivo observations of reversible morphological changes in the production of scoliosis in mice. Clin Orthop and Rel Res 1976, 116:103-111. | |
| Spinal curvatures can routinely be diagnosed in early stages, before pathological deformity of the vertebral elements is induced in response to asymmetric loading. Current clinical approaches involve ‘watching and waiting’ while mild reversible spinal curvatures develop into spinal deformities with potential to cause symptoms throughout life. | Hawes MC, O’Brien JP. The transformation of spinal curvature into spinal deformity: pathological processes and implications for treatment. Scoliosis. 2006 Mar 31; 1(1):3. | |
| Thus, in one study of 187 patients followed for > 15 years after skeletal maturity, 20–29 degree curvatures progressed 10 degrees, on average; 30–39 degree curvatures progressed 12 degrees; 40–49 degree curvatures progressed 15 degrees; and 50–59 degree curvatures progressed 20 degrees. | Ascani E, Bartolozzi P, Logroscino CA, Marchetti PG, Ponte A, Savini R, Travaglini F, Binazzi F, Di Silvestre M: Natural history of untreated IS after skeletal maturity. Spine 1986, 11:784-789. | |
| Structural damage to bone and disc can occur very early in the development of even minor curves. (Xiong)
Yet the damage can be reversed entirely if steps are taken to reverse the loading imbalance while significant growth potential remains.
These data suggest that preventing a state of continuous asymmetric loading in children in early stages of scoliosis will prevent the development of spinal deformities. |
Xiong B, Sevastik JA, Hedlund R, Sevastik B: Radiographic changes at the coronal plane in early scoliosis. Spine 1994, 19:159-74.Mehta MH: Pain provoked scoliosis. Clin Orthop Rel Res 1978, 135:58-65.
Harrington P: Is scoliosis reversible? In vivo observations of reversible morphological changes in the production of scoliosis in mice. Clin Orthop and Rel Res 1976, 116:103-111. Mente PL, Aronsson DD, Stokes IAF, Iatridis JC: Mechanical modulation of growth for the correction of vertebral wedge deformities. J Orthop Res 1999, 17:518-524. |
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| Gender | Brehme showed directional asymmetry to be higher in female patients than in male patients. | Jantz RL, Brehme H. Directional and fluztuating asymmetry in the palmar interdigital ridge-counts. Anthropologischer Anzeiger 1993; 51:59-67. |
| Treatment centers | There are more than 82 SpineCor treatment centers around the world specializing in the treatment of adolescent idiopathic scoliosis in countries like Australia, Canada, China, Colombia, France, Germany, Greece, Hungary, Israel, South Korea, Poland, Singapore, Spain, Switzerland, United Kingdom and the United States. | www.spinecorporation.com |
| Sub-classification of the traditional SRS definition of curve types | The brace is fitted on the patient in accordance to a sub-classification of the traditional SRS definition of curve types.Comparison of X-rays and postural analysis from hundreds of patients led to the development of a new scoliosis classification system taking into account not only the 3-dimensional aspect of each spinal deformity, but the global postural disorganisation. Observation of specific parameters, by combining frontal and sagital X-rays, in order to get the maximum 3D information is involved. | Ponseti IV, Friedman B. Prognosis in idiopathic scoliosis. J Bone Joint Surg. Am 1950;32A(2):381-395.Nguyen VH, Leroux MA, Badeaux J, Zabjek K, Coillard C, Rivard CH.Classification des scolioses thoraco-lombaires gauches selon leur morphologie radiologique et leur géométrie posturale. Annales de chirurgie 1998; 52(8): 752-760. |
| Initial reducibility of the scoliotic curves in the SpineCor brace
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The initial Cobb angle of 99 patients treated by the SpineCor brace was compared to the pre-therapeutic one. The results demonstrated that the reducibility of the scoliotic curves with the brace at the beginning of treatment provides a significant global prognosis index but is difficult to apply individually. Other factors must be considered, such as apical vertebral deformities and the impact of growth velocity on the spinal deformity at the onset of the adolescent growth spent. | Coillard C, Leroux MA, Zabjek KF, Rivard CH. La réductibilité des scolioses idiopathiques dans le traitement orthopédique. Ann Chir 1999; 53(8):781-791. |
| Decreased in the spinal deformation and in the prominence during the SpineCor brace treatment | The close relationship between prominence and spinal curvature was identified by Korovessis and Stamatakis.In the year 2000, Griffet and collaborators decided to quantify the relationship between prominence and spinal deformation expressed by the Cobb angle before and during treatment with the SpineCor brace of 89 IS patients. This study demonstrate that during treatment, the SpineCor patients demonstrated a decreased in the spinal deformation (8,3º) as well as a decreased in the prominence (2.3º). The expressed of the prominence does not correspond to a one-to-one relationship with the Cobb angle, others elements needs to be consider (vertebral rotation, presence of the thoracic cage and its eventual deformation du to the scoliosis).
When the measurement of prominence in the brace is used in combination with the initial Cobb angle and prominence, it is possible to limit the necessity of a radiograph. |
Korovessis PG, Stamatakis MV. Prediction of scoliosis Cobb angle with the use of the scoliometer. Spine 1996; 21:1661-1666.Griffet J, Leroux MA, Badeaux J, et al. Relationship between gibbosity and Cobb angle during treatment of idiopathic scoliosis with the SpineCor brace. Eur Spine J 2000; 9(6):516-522. |
| SpineCor brace effectiveness
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Unique and successful treatment principle and its applicationThe efficiency of the SpineCor brace was first exposed to the scientific community in 2002.
The results obtained with the first series of patients (n=55) treated by this flexible brace. Dr. Coillard and the team of researchers noted that more than 87% patients had a real correction (>5º; n=22) or are stabilized (±5 º; n=26) in their Cobb angle after an average of 20 months treatment duration and 21 months after the end of bracing. The quality of postural and cosmetic results obtained by this new non aggressive therapeutic approach was very surprising and promising. The follow-up at the end of bracing for the first 55 AIS patients treated by the SpineCor brace enabled the authors to establish the first evaluation of the treatment principle and its application revealing a positive therapeutic effect. |
Coillard C, Leroux MA, Badeaux J, Rivard CH. (2002) SPINECOR: a new therapeutic approach for idiopathic scoliosis. Stud Health Technol Inform 88: p. 215-217. |
| Positive therapeutic outcome for AIS patients treated by the dynamic braceThe first survival analysis was performed in 2003 to assess success of treatment during the follow-up period of a group of 195 idiopathic scoliosis patients treated with the flexible brace. This initial cohort of patients (initial Cobb angles between 15 and 50º) reveals a positive treatment outcome; demonstrating a general trend of initial decrease in spinal curvature in brace, followed by a correction and/or stabilization at the end of treatment, which was maintained through 1, and 2 years’ post-treatment follow-up.
For the 29 patients who had a minimum follow-up of 2 years post-bracing, there was an overall correction greater than 5º for 55% of the patients, 38% had stabilization and 7% had worsening by more than 5º. As reported by Montgomery and collaborators , a follow-up of 2 years is sufficient to foresee progression after weaning from the brace. The SpineCor brace provides the opportunity to re-educate and maintain the neuromuscular control of spinal corrective movement through active bio-feedback. Thereafter, it was now clear that the SpineCor system was no longer to be considered has an experimental brace but a true effective orthotic device for the treatment of AIS patients. |
Coillard C, Leroux MA, Zabjek KF, Rivard CH. SpineCor – a non-rigid brace for the treatment of idiopathic scoliosis: post-treatment results. Eur Spine J 2003; 12:141-148. | |
| Support of the SpineCor brace effectiveness in the treatment of AISIn the year 2006, a survival analysis was carried out on a group of 365 AIS patients having agreed to be treated by the dynamic SpineCor brace.
The orthopedic treatment was a success for 84.6 % of the 120 patients having a minimal post-treatment follow-up of 1 year. The results were even more encouraging if one looks at the 26 patients having 5 years post-treatment follow-up: permanent correction in 65.4% of the cases, stabilization in 30.8% and only 3.8% progression of the curve.
This prospective study confirms that the SpineCor brace is effective for the treatment of AIS and tend to reveals a positive treatment outcome in the long run. |
Vachon V, Coillard C, Zabjek KF, Rhalmi S, Rivard CH. (2006) [Survival analysis of a group of 365 idiopathic scoliosis patients treated with the Dynamic SpineCor Brace] Résonances Européennes du rachis.14(43):p. 1782-1786. French. | |
| Sustainable correction and/or stabilization after the SpineCor brace discontinuation The SRS established in 2005 parameters for all future AIS bracing studies in order to be able to make comparison amongst more valid and reliable studies. Such guidelines allow promotion of the effectiveness of different braces using.
A group of researchers (Coillard, Vachon 2007) decided to evaluate the effectiveness of the SpineCor brace following the new standardized criteria proposed by the SRS. 249 patients fitted the criteria for inclusion as suggested by the SRS and 79 patients were still actively being treated. After all, 170 patients had a definitive outcome. Successful treatment (correction >5º or stabilization ±5º) was achieved in 101 patients of the 170 patients from the time of the fitting of the SpineCor brace to the point in which it was discontinued. Comparing the end of bracing Cobb angle to the one at 2 years post-bracing, this study revealed that the follow-up of orthopedic treatment was a success in 95.7 % of the patients. The SpineCor brace is effective for the treatment of AIS supporting the previous papers. It is possible with the SpineCor brace to have sustainable correction or stabilization of scoliotic curves up to 2 years after discontinuation of brace treatment. This particular feature of the SpineCor brace makes it very unique and distinct to the already published literature on brace in which apparent correction obtained during treatment can be expected to be lost over time.
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Richards BS, Bernstein RM, D’Amato CR, et al. Standardization of criteria for adolescent idiopathic scoliosis brace studies: SRS Committee on Bracing and Nonoperative Management. Spine 2005;30:2068-2075.
Coillard C, Vachon V, Circo C, et al. Effectiveness of the SpineCor brace based on the new standardized criteria proposed by the S.R.S. for adolescent idiopathic scoliosis. Journal of Pediatric Orthopaedics 2007; Accepted for publication.
Gabos PG, Bojescul JA, Bowen JR, et al. Long-term follow-up of female patients with idiopathic scoliosis treated with the Wilmington orthosis. J Bone Joint Surg Am 2004;86-A:1891-1899. Bassett GS, Bunnell WP, MacEwen GD. Treatment of idiopathic scoliosis with the Wilmington brace. Results in patients with a twenty to thirty-nine-degree curve. J Bone Joint Surg Am 1986;68:602-605. |
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| Positive outcome in AIS obese patients treated by the SpineCor braceMore and more children are becoming overweight in developed countries (Dehghan et al, 2005). Overweight patients with AIS will have greater curve progression and less successful results following the TLSO orthotic treatment than those who are not overweight.
503 consecutive patients treated using the SpineCor brace from one institution were analyzed, 190 patients were still actively being treated and 133 patients did not fit the research inclusion criteria proposed by the SRS. Finally, 180 patients have a definitive outcome in which 13 patients were considered to be overweight. The results of the study demonstrated that both overweight and normal AIS patients treated by the flexible brace had a positive outcome (62% and 66% of success respectively). We believe that SpineCor bracing is more successful in this cohort of patients since the application of dynamic corrective movements through the shoulders, thorax and pelvis is not adversely effected by excess subcutaneous tissue. Rigid 3-point pressure orthotics in contrast cannot effectively apply forces to the spine of an overweight patient. |
Dehghan, M., Akhtar-Danesh, N. and Merchant, A.T. Nutrition Journal. 4, 24-32, 2005.
O’Neill PJ, Karol LA, Shindle MK, Elerson EE, BrintzenhofeSzoc KM, Katz DE, Farmer Kw, Sponseller PD. Decreased orthotic effectiveness in overweight patients with adolescent idiopathic scoliosis. J Bone Joint Surg Am 2005; 87(5): 1069-1074.
Vachon V, Circo A, Coillard C, Rivard C.H. Positive outcome in overweight patients with adolescent idiopathic scoliosis treated by the SpineCor brace. Accepted to: The 12th World Congress of the International Society for Prosthetics and Orthotics, July 2007.
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