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Adolescent idiopathic scoliosis: Clinical features, evaluation, and diagnosis

Susan A Scherl, MD
Section Editor
William Phillips, MD
Deputy Editor
Mary M Torchia, MD


Scoliosis, lateral curvature of the spine, is a structural alteration that occurs in a variety of conditions. Progression of the curvature during periods of rapid growth can result in significant deformity, which may be accompanied by cardiopulmonary compromise.

The clinical features, diagnosis, and initial evaluation of adolescent idiopathic scoliosis (AIS) will be reviewed here. The management and prognosis of adolescent idiopathic scoliosis are discussed separately. (See "Adolescent idiopathic scoliosis: Management and prognosis".)


Scoliosis is defined as curvature of the spine in the coronal plane (image 1). It is typically accompanied by a variable degree of rotation of the spinal column. By convention, ≥10° of curvature (as measured by the Cobb angle (image 2)) defines scoliosis [1]. Curves with Cobb angle <10° are within the normal limits of spinal asymmetry and have no long-term clinical significance. The direction (right or left) of a scoliotic curve is defined by the curve's convexity (image 1). The location is defined by the apical vertebra (the one that most deviated and rotated from midline) [2]. (See 'Radiographic evaluation' below.)

Idiopathic scoliosis is scoliosis for which there is no definite etiology unlike neuromuscular, congenital, or syndromic types. (See 'Differential diagnosis' below.)

Idiopathic scoliosis is divided into three subcategories based upon the patient's age at presentation:


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  1. Kane WJ. Scoliosis prevalence: a call for a statement of terms. Clin Orthop Relat Res 1977; :43.
  2. Tachdijan MO. The Spine. In: Clinical Pediatric Orthopedics: The Art of Diagnosis and Principles of Management, Appleton and Lange, Stamford, CT 1997. p.325.
  3. Stirling AJ, Howel D, Millner PA, et al. Late-onset idiopathic scoliosis in children six to fourteen years old. A cross-sectional prevalence study. J Bone Joint Surg Am 1996; 78:1330.
  4. McAlister WH, Shackelford GD. Classification of spinal curvatures. Radiol Clin North Am 1975; 13:93.
  5. Goldstein LA, Waugh TR. Classification and terminology of scoliosis. Clin Orthop Relat Res 1973; :10.
  6. Riseborough EJ, Wynne-Davies R. A genetic survey of idiopathic scoliosis in Boston, Massachusetts. J Bone Joint Surg Am 1973; 55:974.
  7. Roach JW. Adolescent idiopathic scoliosis. Orthop Clin North Am 1999; 30:353.
  8. Gore DR, Passehl R, Sepic S, Dalton A. Scoliosis screening: results of a community project. Pediatrics 1981; 67:196.
  9. Miller NH. Cause and natural history of adolescent idiopathic scoliosis. Orthop Clin North Am 1999; 30:343.
  10. Weinstein SL. Adolescent idiopathic scoliosis: prevalence and natural history. Instr Course Lect 1989; 38:115.
  11. Goodbody CM, Sankar WN, Flynn JM. Presentation of Adolescent Idiopathic Scoliosis: The Bigger the Kid, the Bigger the Curve. J Pediatr Orthop 2017; 37:41.
  12. Margalit A, McKean G, Constantine A, et al. Body Mass Hides the Curve: Thoracic Scoliometer Readings Vary by Body Mass Index Value. J Pediatr Orthop 2016.
  13. Inoue M, Minami S, Kitahara H, et al. Idiopathic scoliosis in twins studied by DNA fingerprinting: the incidence and type of scoliosis. J Bone Joint Surg Br 1998; 80:212.
  14. Kesling KL, Reinker KA. Scoliosis in twins. A meta-analysis of the literature and report of six cases. Spine (Phila Pa 1976) 1997; 22:2009.
  15. Wynne-Davies R. Familial (idiopathic) scoliosis. A family survey. J Bone Joint Surg Br 1968; 50:24.
  16. Simony A, Carreon LY, Hjmark K, et al. Concordance Rates of Adolescent Idiopathic Scoliosis in a Danish Twin Population. Spine (Phila Pa 1976) 2016; 41:1503.
  17. Justice CM, Miller NH, Marosy B, et al. Familial idiopathic scoliosis: evidence of an X-linked susceptibility locus. Spine (Phila Pa 1976) 2003; 28:589.
  18. Salehi LB, Mangino M, De Serio S, et al. Assignment of a locus for autosomal dominant idiopathic scoliosis (IS) to human chromosome 17p11. Hum Genet 2002; 111:401.
  19. Chan V, Fong GC, Luk KD, et al. A genetic locus for adolescent idiopathic scoliosis linked to chromosome 19p13.3. Am J Hum Genet 2002; 71:401.
  20. Clough M, Justice CM, Marosy B, Miller NH. Males with familial idiopathic scoliosis: a distinct phenotypic subgroup. Spine (Phila Pa 1976) 2010; 35:162.
  21. Sharma S, Gao X, Londono D, et al. Genome-wide association studies of adolescent idiopathic scoliosis suggest candidate susceptibility genes. Hum Mol Genet 2011; 20:1456.
  22. Gao X, Gordon D, Zhang D, et al. CHD7 gene polymorphisms are associated with susceptibility to idiopathic scoliosis. Am J Hum Genet 2007; 80:957.
  23. Axenovich TI, Zaidman AM, Zorkoltseva IV, et al. Segregation analysis of idiopathic scoliosis: demonstration of a major gene effect. Am J Med Genet 1999; 86:389.
  24. Ward K, Ogilvie J, Argyle V, et al. Polygenic inheritance of adolescent idiopathic scoliosis: a study of extended families in Utah. Am J Med Genet A 2010; 152A:1178.
  25. Ahn UM, Ahn NU, Nallamshetty L, et al. The etiology of adolescent idiopathic scoliosis. Am J Orthop (Belle Mead NJ) 2002; 31:387.
  26. Lonstein JE. Adolescent idiopathic scoliosis. Lancet 1994; 344:1407.
  27. Liebergall M, Floman Y, Eldor A. Functional, biochemical, and structural anomalies in platelets of patients with idiopathic scoliosis. J Spinal Disord 1989; 2:126.
  28. Weinstein SL, Zavala DC, Ponseti IV. Idiopathic scoliosis: long-term follow-up and prognosis in untreated patients. J Bone Joint Surg Am 1981; 63:702.
  29. Pehrsson K, Bake B, Larsson S, Nachemson A. Lung function in adult idiopathic scoliosis: a 20 year follow up. Thorax 1991; 46:474.
  30. Branthwaite MA. Cardiorespiratory consequences of unfused idiopathic scoliosis. Br J Dis Chest 1986; 80:360.
  31. Dickson RA. Conservative treatment for idiopathic scoliosis. J Bone Joint Surg Br 1985; 67:176.
  32. McPhail GL, Ehsan Z, Howells SA, et al. Obstructive lung disease in children with idiopathic scoliosis. J Pediatr 2015; 166:1018.
  33. Newton PO, Wenger DR, Yaszay B. Idiopathic scoliosis. In: Lovell and Winter's Pediatric Orthopaedics, 7th ed, Weinstein SL, Flynn JM (Eds), Lippincott Williams & Wilkins, Philadelphia 2014. p.629.
  34. Sponseller PD. Bone, joint, and muscle problems. In: Oski's Pediatrics: Principles and Practice, 4th ed, McMillan JA, Feigin RD, DeAngelis CD, Jones MD Jr (Eds), Lippincott Williams & Wilkins, Philadelphia 2006. p.2488.
  35. Mehta MH. Pain provoked scoliosis. Observations on the evolution of the deformity. Clin Orthop Relat Res 1978; :58.
  36. Ramirez N, Johnston CE, Browne RH. The prevalence of back pain in children who have idiopathic scoliosis. J Bone Joint Surg Am 1997; 79:364.
  37. Renshaw TS. Idiopathic scoliosis in children. Curr Opin Pediatr 1993; 5:407.
  38. Richards BS, Bernstein RM, D'Amato CR, Thompson GH. Standardization of criteria for adolescent idiopathic scoliosis brace studies: SRS Committee on Bracing and Nonoperative Management. Spine (Phila Pa 1976) 2005; 30:2068.
  39. Barnes PD, Brody JD, Jaramillo D, et al. Atypical idiopathic scoliosis: MR imaging evaluation. Radiology 1993; 186:247.
  40. Mejia EA, Hennrikus WL, Schwend RM, Emans JB. A prospective evaluation of idiopathic left thoracic scoliosis with magnetic resonance imaging. J Pediatr Orthop 1996; 16:354.
  41. Schwend RM, Hennrikus W, Hall JE, Emans JB. Childhood scoliosis: clinical indications for magnetic resonance imaging. J Bone Joint Surg Am 1995; 77:46.
  42. Wu L, Qiu Y, Wang B, et al. The left thoracic curve pattern: a strong predictor for neural axis abnormalities in patients with "idiopathic" scoliosis. Spine (Phila Pa 1976) 2010; 35:182.
  43. Loder RT, Stasikelis P, Farley FA. Sagittal profiles of the spine in scoliosis associated with an Arnold-Chiari malformation with or without syringomyelia. J Pediatr Orthop 2002; 22:483.
  44. Grossman TW, Mazur JM, Cummings RJ. An evaluation of the Adams forward bend test and the scoliometer in a scoliosis school screening setting. J Pediatr Orthop 1995; 15:535.
  45. Huang SC. Cut-off point of the Scoliometer in school scoliosis screening. Spine (Phila Pa 1976) 1997; 22:1985.
  46. Bunnell WP. Outcome of spinal screening. Spine (Phila Pa 1976) 1993; 18:1572.
  47. Côté P, Kreitz BG, Cassidy JD, et al. A study of the diagnostic accuracy and reliability of the Scoliometer and Adam's forward bend test. Spine (Phila Pa 1976) 1998; 23:796.
  48. Goldberg CJ, Dowling FE, Fogarty EE, Moore DP. School scoliosis screening and the United States Preventive Services Task Force. An examination of long-term results. Spine (Phila Pa 1976) 1995; 20:1368.
  49. Karachalios T, Sofianos J, Roidis N, et al. Ten-year follow-up evaluation of a school screening program for scoliosis. Is the forward-bending test an accurate diagnostic criterion for the screening of scoliosis? Spine (Phila Pa 1976) 1999; 24:2318.
  50. Viviani GR, Budgell L, Dok C, Tugwell P. Assessment of accuracy of the scoliosis school screening examination. Am J Public Health 1984; 74:497.
  51. Bunnell WP. An objective criterion for scoliosis screening. J Bone Joint Surg Am 1984; 66:1381.
  52. Murrell GA, Coonrad RW, Moorman CT 3rd, Fitch RD. An assessment of the reliability of the Scoliometer. Spine (Phila Pa 1976) 1993; 18:709.
  53. Franko OI, Bray C, Newton PO. Validation of a scoliometer smartphone app to assess scoliosis. J Pediatr Orthop 2012; 32:e72.
  54. Balg F, Juteau M, Theoret C, et al. Validity and reliability of the iPhone to measure rib hump in scoliosis. J Pediatr Orthop 2014; 34:774.
  55. Qiao J, Xu L, Zhu Z, et al. Inter- and intraobserver reliability assessment of the axial trunk rotation: manual versus smartphone-aided measurement tools. BMC Musculoskelet Disord 2014; 15:343.
  56. Amendt LE, Ause-Ellias KL, Eybers JL, et al. Validity and reliability testing of the Scoliometer. Phys Ther 1990; 70:108.
  57. Korovessis PG, Stamatakis MV. Prediction of scoliotic cobb angle with the use of the scoliometer. Spine (Phila Pa 1976) 1996; 21:1661.
  58. Ashworth MA, Hancock JA, Ashworth L, Tessier KA. Scoliosis screening. An approach to cost/benefit analysis. Spine (Phila Pa 1976) 1988; 13:1187.
  59. Charry O, Koop S, Winter R, et al. Syringomyelia and scoliosis: a review of twenty-five pediatric patients. J Pediatr Orthop 1994; 14:309.
  60. Zadeh HG, Sakka SA, Powell MP, Mehta MH. Absent superficial abdominal reflexes in children with scoliosis. An early indicator of syringomyelia. J Bone Joint Surg Br 1995; 77:762.
  61. Yngve D. Abdominal reflexes. J Pediatr Orthop 1997; 17:105.
  62. Screening for Idiopathic Scoliosis in Adolescents, Topic Page. June 2004. U.S. Preventive Services Task Force. www.ahrq.gov/clinic/uspstf/uspsaisc.htm (Accessed on February 28, 2008).
  63. Bunnell WP. Selective screening for scoliosis. Clin Orthop Relat Res 2005; :40.
  64. Cassar-Pullicino VN, Eisenstein SM. Imaging in scoliosis: what, why and how? Clin Radiol 2002; 57:543.
  65. Skaggs DL. Referrals from scoliosis screenings. Am Fam Physician 2001; 64:32, 34.
  66. Greiner KA. Adolescent idiopathic scoliosis: radiologic decision-making. Am Fam Physician 2002; 65:1817.
  67. American College of Radiology. ACR-SPR-SSR practice parameter for the performance of radiography for scoliosis in children. 2014. Available at: www.acr.org/Quality-Safety/Standards-Guidelines/Practice-Guidelines-by-Modality/Pediatric (Accessed on April 11, 2015).
  68. Ouellet JA, LaPlaza J, Erickson MA, et al. Sagittal plane deformity in the thoracic spine: a clue to the presence of syringomyelia as a cause of scoliosis. Spine (Phila Pa 1976) 2003; 28:2147.
  69. Spiegel DA, Flynn JM, Stasikelis PJ, et al. Scoliotic curve patterns in patients with Chiari I malformation and/or syringomyelia. Spine (Phila Pa 1976) 2003; 28:2139.
  70. Glaser DA, Doan J, Newton PO. Comparison of 3-dimensional spinal reconstruction accuracy: biplanar radiographs with EOS versus computed tomography. Spine (Phila Pa 1976) 2012; 37:1391.
  71. Faria R, McKenna C, Wade R, et al. The EOS 2D/3D X-ray imaging system: a cost-effectiveness analysis quantifying the health benefits from reduced radiation exposure. Eur J Radiol 2013; 82:e342.
  72. King HA, Moe JH, Bradford DS, Winter RB. The selection of fusion levels in thoracic idiopathic scoliosis. J Bone Joint Surg Am 1983; 65:1302.
  73. Lenke LG. Lenke classification system of adolescent idiopathic scoliosis: treatment recommendations. Instr Course Lect 2005; 54:537.
  74. Dickson RA, Weinstein SL. Bracing (and screening)--yes or no? J Bone Joint Surg Br 1999; 81:193.
  75. Oda M, Rauh S, Gregory PB, et al. The significance of roentgenographic measurement in scoliosis. J Pediatr Orthop 1982; 2:378.
  76. Goldberg MS, Poitras B, Mayo NE, et al. Observer variation in assessing spinal curvature and skeletal development in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 1988; 13:1371.
  77. Morrissy RT, Goldsmith GS, Hall EC, et al. Measurement of the Cobb angle on radiographs of patients who have scoliosis. Evaluation of intrinsic error. J Bone Joint Surg Am 1990; 72:320.
  78. Pruijs JE, Hageman MA, Keessen W, et al. Variation in Cobb angle measurements in scoliosis. Skeletal Radiol 1994; 23:517.
  79. Dang NR, Moreau MJ, Hill DL, et al. Intra-observer reproducibility and interobserver reliability of the radiographic parameters in the Spinal Deformity Study Group's AIS Radiographic Measurement Manual. Spine (Phila Pa 1976) 2005; 30:1064.
  80. Carman DL, Browne RH, Birch JG. Measurement of scoliosis and kyphosis radiographs. Intraobserver and interobserver variation. J Bone Joint Surg Am 1990; 72:328.
  81. Hardesty CK, Aronson J, Aronson EA, et al. Interobserver variability using a commercially available system of archived digital radiography with integrated computer-assisted measurements for scoliosis Cobb angles. J Pediatr Orthop 2013; 33:163.
  82. Lonstein JE, Carlson JM. The prediction of curve progression in untreated idiopathic scoliosis during growth. J Bone Joint Surg Am 1984; 66:1061.
  83. Sanders JO, Browne RH, Cooney TE, et al. Correlates of the peak height velocity in girls with idiopathic scoliosis. Spine (Phila Pa 1976) 2006; 31:2289.
  84. Little DG, Sussman MD. The Risser sign: a critical analysis. J Pediatr Orthop 1994; 14:569.
  85. Sanders JO, Khoury JG, Kishan S, et al. Predicting scoliosis progression from skeletal maturity: a simplified classification during adolescence. J Bone Joint Surg Am 2008; 90:540.
  86. Wang WW, Xia CW, Zhu F, et al. Correlation of Risser sign, radiographs of hand and wrist with the histological grade of iliac crest apophysis in girls with adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2009; 34:1849.
  87. Ryan PM, Puttler EG, Stotler WM, Ferguson RL. Role of the triradiate cartilage in predicting curve progression in adolescent idiopathic scoliosis. J Pediatr Orthop 2007; 27:671.
  88. Charles YP, Diméglio A, Canavese F, Daures JP. Skeletal age assessment from the olecranon for idiopathic scoliosis at Risser grade 0. J Bone Joint Surg Am 2007; 89:2737.
  89. Diméglio A, Charles YP, Daures JP, et al. Accuracy of the Sauvegrain method in determining skeletal age during puberty. J Bone Joint Surg Am 2005; 87:1689.
  90. Maenza RA. Juvenile and adolescent idiopathic scoliosis: magnetic resonance imaging evaluation and clinical indications. J Pediatr Orthop B 2003; 12:295.
  91. Redla S, Sikdar T, Saifuddin A. Magnetic resonance imaging of scoliosis. Clin Radiol 2001; 56:360.
  92. Davids JR, Chamberlin E, Blackhurst DW. Indications for magnetic resonance imaging in presumed adolescent idiopathic scoliosis. J Bone Joint Surg Am 2004; 86-A:2187.
  93. Malfair D, Flemming AK, Dvorak MF, et al. Radiographic evaluation of scoliosis: review. AJR Am J Roentgenol 2010; 194:S8.
  94. Diab M, Landman Z, Lubicky J, et al. Use and outcome of MRI in the surgical treatment of adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2011; 36:667.
  95. Goldberg CJ, Moore DP, Fogarty EE, Dowling FE. Left thoracic curve patterns and their association with disease. Spine (Phila Pa 1976) 1999; 24:1228.
  96. Marsh JS. Screening for scoliosis. Pediatr Rev 1993; 14:297.
  97. Bremberg S, Nilsson-Berggren B. School screening for adolescent idiopathic scoliosis. J Pediatr Orthop 1986; 6:564.
  98. Willner S. Development of trunk asymmetries and structural scoliosis in prepuberal school children in Malmö: follow-up study of children 10-14 years of age. J Pediatr Orthop 1984; 4:452.
  99. Lonstein JE, Winter RB. The Milwaukee brace for the treatment of adolescent idiopathic scoliosis. A review of one thousand and twenty patients. J Bone Joint Surg Am 1994; 76:1207.
  100. Montgomery F, Willner S. The natural history of idiopathic scoliosis. A study of the incidence of treatment. Spine (Phila Pa 1976) 1988; 13:401.
  101. Montgomery F, Willner S. Screening for idiopathic scoliosis. Comparison of 90 cases shows less surgery by early diagnosis. Acta Orthop Scand 1993; 64:456.
  102. Richards BS, Vitale MG. Screening for idiopathic scoliosis in adolescents. An information statement. J Bone Joint Surg Am 2008; 90:195.
  103. Hresko MT, Talwalkar V, Schwend R, AAOS, SRS, and POSNA. Early Detection of Idiopathic Scoliosis in Adolescents. J Bone Joint Surg Am 2016; 98:e67.
  104. Screening for adolescent idiopathic scoliosis. Policy statement. US Preventive Services Task Force. JAMA 1993; 269:2664.
  105. Yawn BP, Yawn RA, Hodge D, et al. A population-based study of school scoliosis screening. JAMA 1999; 282:1427.
  106. Koukourakis I, Giaourakis G, Kouvidis G, et al. Screening school children for scoliosis on the island of Crete. J Spinal Disord 1997; 10:527.
  107. Reamy BV, Slakey JB. Adolescent idiopathic scoliosis: review and current concepts. Am Fam Physician 2001; 64:111.
  108. Asher MA, Burton DC. Adolescent idiopathic scoliosis: natural history and long term treatment effects. Scoliosis 2006; 1:2.
  109. Weinstein SL, Dolan LA, Spratt KF, et al. Health and function of patients with untreated idiopathic scoliosis: a 50-year natural history study. JAMA 2003; 289:559.
  110. Pruijs JE, van der Meer R, Hageman MA, et al. The benefits of school screening for scoliosis in the central part of The Netherlands. Eur Spine J 1996; 5:374.
  111. Bunge EM, Juttmann RE, van Biezen FC, et al. Estimating the effectiveness of screening for scoliosis: a case-control study. Pediatrics 2008; 121:9.
  112. Goldberg CJ, Dowling FE, Hall JE, Emans JB. A statistical comparison between natural history of idiopathic scoliosis and brace treatment in skeletally immature adolescent girls. Spine (Phila Pa 1976) 1993; 18:902.
  113. Screening for adolescent idiopathic scoliosis. Review article. US Preventive Services Task Force. JAMA 1993; 269:2667.
  114. Dolan LA, Donnelly MJ, Spratt KF, Weinstein SL. Professional opinion concerning the effectiveness of bracing relative to observation in adolescent idiopathic scoliosis. J Pediatr Orthop 2007; 27:270.
  115. Dolan LA, Weinstein SL. Surgical rates after observation and bracing for adolescent idiopathic scoliosis: an evidence-based review. Spine (Phila Pa 1976) 2007; 32:S91.
  116. Weinstein SL, Dolan LA, Wright JG, Dobbs MB. Effects of bracing in adolescents with idiopathic scoliosis. N Engl J Med 2013; 369:1512.
  117. American Academy of Family Physicians (AAFP). Clinical preventive services. January 2010. www.aafp.org/online/en/home/clinical/exam.html (Accessed on August 31, 2011).
  118. Canadian Task Force on the Periodic Health Examination. In: Canadian Guide to Clinical Preventive Care, Canada Communication Group, Ottawa 1994. p.346.
  119. SRS/POSNA/AAOS/AAP Position Statement. Screening for the Early Detection for Idiopathic Scoliosis in Adolescents. September 2015 https://www.srs.org/about-srs/news-and-announcements/position-statement---screening-for-the-early-detection-for-idiopathic-scoliosis-in-adolescents (Accessed on March 29, 2016).
  120. Idiopathic Scoliosis in Adolescents: Screening. June 2004. US Preventive Services Task Force. Available at: www.uspreventiveservicestaskforce.org/Page/Topic/recommendation-summary/idiopathic-scoliosis-in-adolescents-screening (Accessed on May 20, 2015).