Articles

Predictors of Curve Flexibility in Adolescent Idiopathic Scoliosis: a Retrospective Study of 100 Patients

Abstract

Curve flexibility in adolescent idiopathic scoliosis (AIS) was one of the major concerns of spinal surgeons since the evolution of surgical correction techniques. In this respect, many tried to identify which criteria denote more rigid curve. In the present study, we aimed toward determining important factors influencing AIS curve flexibility on supine bending films. We assessed radiographs of 100 patients with AIS for direction of curves, number of involved vertebrae, apical vertebral translation and rotation, magnitude of main thoracic curve and T5-T12 kyphosis. Statistical analysis performed via stepwise linear regression model with these variables plus age and sex against flexibility index. According to regression analysis, there was a clear relationship between flexibility indexes (FI) and magnitude of main thoracic curve at all (P<0.001). When we consider flexible curves (FI>50%) against rigid curves, apical vertebral rotation was a major determinant of curve flexibility also (P<0.001). Adolescent idiopathic scoliosis curves with larger Cobb's angle and apical vertebral rotation show less flexibility on supine bending films.

Kim HJ, Blanco JS, Widmann RF. Update on the management of idiopathic scoliosis. Curr Opin Pediatr 2009;21(1):55-64.

Weinstein SL. Natural History. Spine 1999;24(24):2592-600.

Sun YQ, Samartizis D, Cheung KM, et al. The "X-Factor"index: a new parameter for the assessment of adolescent idiopathic scoliosis correction. Eur Spine J 2011;20(1):144-50.

Hamzaoglu A, Talu U, Tezer M, et al. Assessment of Curve Flexibility in Adolescent Idiopathic Scoliosis. Spine 2005;30(14):1637-42.

Clamp JA, Anderws JR, Grevitt MP. A study of the radiologic predictor of curve flexibility in adolescent idiopathic scoliosis. J Spinal Disord Tech 2008;21(3):213-5.

Hasler CC, Hefti F, Buchler P. Coronal plane segmental flexibility in thoracic adolescent idiopathic scoliosis assessed by fulcrum-bending radiographs. Eur Spine J 2010;19(5):732-8.

Lamarre ME, Parent S, Labelle H, et al. Assessment of Spinal Flexibility in Adolescent Idiopathic Scoliosis. Suspension versus Side-Bending Radiography. Spine 2009;34(6):591-7.

Davis BJ, Gadgil A, Trivedi J, et al. Traction Radiography Performed under General Anesthetic: A New Technique for Assessing Idiopathic Scoliosis Curves. Spine 2004;29(21):2466-70.

Watanabe K, Kawakami N, Nishiwaki Y, et al. Traction Versus Supine Side-bending Radiographs in Determining Flexibility, What Factors Influence These Techniques? Spine 2007;32(23):2604-9.

King HA, Moe JH, Bradford DS, et al. The selection of fusion levels in thoracic idiopathic scoliosis. J Bone Joint Surg Am 1983;65(9):1302-13.

Knapp DR Jr, Price CT, Jones ET, et al. Choosing fusion levels in progressive thoracic idiopathic scoliosis. Spine 1992;17(10):1159-65.

Aronsson DD, Stokes IA, Ronchetti PJ, et al. Surgical correction of vertebral axial rotation in adolescent idiopathic scoliosis: prediction by lateral bending films. J Spinal Disord 1996;9(3):214-9. 13. Luhmann SJ, Lenke LG, Kim YJ, et al. Thoracic Adolescent Idiopathic Scoliosis Curves Between 70 degrees and 100 degrees: Is Anterior Release Necessary? Spine 2005;30(18):2061-7.

Luk KD, Cheung WY, Wong Y, et al. The predictive value of the fulcrum bending radiograph in spontaneous apical vertebral derotation in adolescent idiopathic scoliosis. Spine 2012;37(15):E922-6.

Cheung WY, Lenke LG, Luk KD. Prediction of scoliosis correction with thoracic segmental pedicle screw constructs using fulcrum bending radiogeaphs. Spine 2010;35(5):557-61.

Li J, Dumonski ML, Samartzis D, et al. Coronal deformity correction in adolescent idiopathic scoliosis patients using the fulcrum – bending radiograph:a prospective comparative analysis of the proximal thoracic, main thoracic, and thoracolumbar/lumbar curves. Eur Spine J 2011;20(1):105-11.

Liu RW, Teng AL, Armstrong DG. Comparison of supine bending,Push-Prone, and traction under general anesthesia radiographs in correction in adolescent idiopathic scoliosis. Spine 2010;35(4):416-22.

Chen ZQ, Zhao YF, Bai YS, et al. Factors affecting curve flexibility skeletally immature and mature idiopathic scoliosis. J Orthop Sci 2011;16(2):133-8.

Ameri E, Behtash H, Mobini B, et al. Radiographic outcome of surgical treatment of adolescent idiopathic scoliosis in males versus females. Scoliosis 2008;3(1):12.

Files
IssueVol 53, No 3 (2015) QRcode
SectionArticles
Keywords
Adolescent idiopathic scoliosis Spinal flexibility Supine bending films Imaging

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
How to Cite
1.
Ameri E, Behtash H, Mobini B, Daraie A. Predictors of Curve Flexibility in Adolescent Idiopathic Scoliosis: a Retrospective Study of 100 Patients. Acta Med Iran. 1;53(3):182-185.