Progression Risk
Studies show that curves end up over 40 degrees at the end of growth are at risk of further progression in adulthood. Curves over 45 degrees are often considered to be in the surgical range. Other studies show that sex/gender, age, curve size and curve type are predictive factors of risk of progression. The following ‘Progression Risk’ calculator determines the risk of progression to a curve > 45 degrees
Sex:
Age:
Risser:
Curve Size:
Curve Type:
Disclaimer. The ‘Progression Risk Calculator’ is provided for estimation only. Actual results can and will vary.
Created By
Gez Bowman CO, MBAPO
Assumptions
None.
References
“the following were associated with a high risk of curve progression: sex (girls); curve pattern (right thoracic and double curves in girls, and right lumbar curves in boys); maturity (girls before the onset of menses); age (time of pubertal growth spurt)”
Soucacos PN, Zacharis K, Gelalis J, Soultanis K, Kalos N, Beris A, Xenakis T, Johnson EO. Assessment of curve progression in idiopathic scoliosis. Eur Spine J. 1998;7(4):270-7.
“patients with a Risser 0 or 1, who had an initial Cobb angle between 20° and 29°, 68% of patients’ scoliotic curve deteriorated during growth”
Lonstein JE, Carlson JM. The prediction of curve progression in untreated idiopathic scoliosis during growth. J Bone Joint Surg Am. 1984;66(7):1061-71
“evidence supported age, curve pattern, initial Cobb angle, and skeletal immaturity as predictors of progression”
Noshchenko A, Hoffecker L, Lindley EM et al (2015) Predictors of spine deformity progression in adolescent idiopathic scoliosis: a systematic review with meta-analysis. World J Orthop 6:537–558.
“Initial Cobb angle > 25° was predictive of curve progression”
Wong, L.P.K.; Cheung, P.W.H.; Cheung, J.P.Y. Curve Type, Flexibility, Correction, and Rotation Are Predictors of Curve Progression in Patients with Adolescent Idiopathic Scoliosis Undergoing Conservative Treatment: A Systematic Review. Bone Jt. J. 2022, 104, 424–432
“Skeletal maturity and curve magnitude have strong predictive value for future curve progression.”
Johnson MA, Flynn JM, Anari JB, Gohel S, Cahill PJ, Winell JJ, Baldwin KD. Risk of Scoliosis Progression in Nonoperatively Treated Adolescent Idiopathic Scoliosis Based on Skeletal Maturity. J Pediatr Orthop. 2021 Oct 1;41(9):543-548.
“for progression over 40° the major predictor is Cobb degrees at start”
Donzelli S, Zaina F, Negrini S. Predicting scoliosis progression: a challenge for researchers and clinicians. EClinicalMedicine. 2020 Jan 6;18:100244.
Johnson MA, Flynn JM, Anari JB, Gohel S, Cahill PJ, Winell JJ, Baldwin KD. Risk of Scoliosis Progression in Nonoperatively Treated Adolescent Idiopathic Scoliosis Based on Skeletal Maturity. J Pediatr Orthop. 2021 Oct 1;41(9):543-548.
Johnson MA, Gohel S, Flynn JM, Anari JB, Cahill PJ, Winell JJ, Baldwin KD. “Will I Need a Brace?”: likelihood of curve progression to bracing range in adolescent idiopathic scoliosis. Spine Deform. 2022 May;10(3):537-542.
https://uihc.org/childrens/predicting-prognosis-untreated-patients-adolescent-idiopathic-scoliosis-ais-skeletal
https://scoliosiscarecenters.com/idiopathic-scoliosis-progression-risk-calculator/
Derivations
Curves < 15 degrees have negligible Risk
Curves >30 degrees (if skeletally immature) have 100% Risk
Risk reduces as skeletal maturity increases
For Right Thoracic Curves or Double Curves, Risk > Other Curves Risk
Male Risk ~9% < Female Risk