Original ArticleFactors That Influence In-Brace Correction in Patients with Adolescent Idiopathic Scoliosis
Introduction
Adolescent idiopathic scoliosis (AIS) is a complex 3-dimensional deformity of the spine with a lateral curvature >10° that affects ∼2%–3% of adolescents.1 A brace has been used for the management of skeletally immature patients with mild AIS for nearly 45 years. The effectiveness of the brace has been controversial for many years owing to the shortage of level 1 data.2, 3, 4, 5, 6 To solve the controversy, the Scoliosis Research Society has proposed the standardization of criteria for future AIS brace studies.7 The Bracing in Adolescent Idiopathic Scoliosis Trial by Weinstein et al.8 has confirmed the efficacy of brace treatment. In their study, the brace group had a greater success rate compared with the observation group (72% vs. 48%). Thus, bracing has become the reference standard for the conservative treatment of AIS.
Despite the high rate of bracing success, some patients will still experience bracing failure. Previous studies have found that in-brace correction, compliance, curve type, Risser sign, body mass index, and gender can contribute to the failure of brace treatment.9, 10, 11, 12, 13, 14, 15 Of these factors, in-brace correction might be the most important predictive factor for curve progression in braced patients with AIS.5, 6, 9 In-brace correction refers to the percentage of decrease in the curve size at the initial brace prescription. However, unlike most established surgical criteria, no definite in-brace correction has been determined that can expect to result in positive outcomes from brace treatment. Previous investigators have reported several cutoff points for in-brace correction to stratify patients with different bracing outcomes, including 10%, 30%, 40%, 50%, and 60%.4, 9, 16, 17, 18 An in-brace correction of 50% has been widely recognized as the aim of brace treatment in clinical practice.3, 5 Given the significance of in-brace correction, some studies have been performed to determine the best method to predict the in-brace correction. Ohrt-Nissen et al.19 reported that supine lateral bending radiographs could closely estimate the expected in-brace correction. Cheung et al.20 found a significant correlation between the supine Cobb angle and in-brace Cobb angle. In the study by Weiss et al.,21 in-brace correction was found to negatively correlate with the Risser sign, patient age, and primary curve Cobb angle. However, the potential risk factors for in-brace correction have not been well elucidated. The purpose of the present study was to identify the factors influencing in-brace correction in patients with AIS.
Section snippets
Subjects
The data from all the patients who had undergone brace treatment in our scoliosis center from July 2015 to October 2017 were reviewed. Our institutional review board approved the present study. The inclusion criteria were in accordance with the standardization of criteria proposed by the Scoliosis Research Society: patient age, ≥10 years; Risser sign, 0–2; primary curve angles, 25°–40°; no previous treatment; and, if female, either premenarchal or <1 year postmenarchal.7 A total of 112 patients
Basic Characteristics
We included 112 patients with AIS (18 boys and 94 girls) in the present study. The mean age was 12.59 ± 1.18 years (range, 10–15), and mean stage of the Risser sign was 1.12 ± 0.78. The initial major Cobb angle was 32.14° ± 4.61° (range, 25°–40°), and the initial in-brace Cobb angle was 13.38° ± 7.90° (range, 0°–31°). The mean in-brace correction was 59.29% ± 22.33% (range, 16.22%–100.00%).
Factors Identified to Affect In-Brace Correction
A correlation analysis was performed between in-brace correction and some study parameters (Table 1). A
Discussion
The aim of brace treatment of AIS is to prevent curve progression. Evidence has shown that a brace can change the natural history of scoliosis in adolescents.6, 8, 17, 18, 24, 25, 26 In the Bracing in Adolescent Idiopathic Scoliosis Trial, brace treatment was successful in 72% of patients compared with the success of observation in 48% of patients.8 In-brace correction and compliance are the 2 main predictors for the final outcome of brace treatment in patients with AIS.22, 26 Previous studies
Conclusions
The in-brace correction with the Gensingen brace in the present study was 59.29% ± 22.33% (range, 16.22%–100.00%). Our results showed that the major curve Cobb angle, minor curve Cobb angle, total curve Cobb angle, sagittal and coronal balance, and LPR are related to in-brace correction. Further studies should focus on the relationship between the bracing outcomes and these factors. The present study has provided some useful information regarding brace design and fabrication.
References (33)
Adolescent idiopathic scoliosis, bracing, and the Hueter-Volkmann principle
Spine Journal
(2003)- et al.
Efficacy of nighttime brace in preventing progression of idiopathic scoliosis of less than 25 degrees
Orthop Traumatol Surg Res
(2017) Adolescent idiopathic scoliosis, bracing, and the Hueter-Volkmann principle
Spine J
(2003)- et al.
School screening and point prevalence of adolescent idiopathic scoliosis in 4000 Norwegian children aged 12 years
Scoliosis
(2011) - et al.
Outcome assessment of bracing in adolescent idiopathic scoliosis by the use of the SRS-22 questionnaire
Int Orthop
(2007) - et al.
Effectiveness of the Charleston bending brace in the treatment of single-curve idiopathic scoliosis
J Pediatr Orthop
(2002) - et al.
The Boston bracing system for idiopathic scoliosis: follow-up results in 295 patients
Spine (Phila Pa 1976)
(1986) - et al.
Treatment of idiopathic scoliosis in the Milwaukee brace
J Bone Joint Surg Am
(1980) - et al.
Standardization of criteria for adolescent idiopathic scoliosis brace studies: SRS Committee on Bracing and Nonoperative Management
Spine (Phila Pa 1976)
(2005) - et al.
Effects of bracing in adolescents with idiopathic scoliosis
N Engl J Med
(2013)
Initial correction rate can be predictive of the outcome of brace treatment in patients with adolescent idiopathic scoliosis
Clin Spine Surg
Brace success is related to curve type in patients with adolescent idiopathic scoliosis
J Bone Joint Surg Am
Low body mass index can be predictive of bracing failure in patients with adolescent idiopathic scoliosis: a retrospective study
Eur Spine J
Flexibility predicts curve progression in providence nighttime bracing of patients with adolescent idiopathic scoliosis
Spine (Phila Pa 1976)
Effect of compliance counseling on brace use and success in patients with adolescent idiopathic scoliosis
J Bone Joint Surg Am
The effect of the Risser stage on bracing outcome in adolescent idiopathic scoliosis
J Bone Joint Surg Am
Cited by (23)
Incidence and Risk Factors of Cervical Kyphosis in Patients with Adolescent Idiopathic Scoliosis
2019, World NeurosurgeryCitation Excerpt :Adolescent idiopathic scoliosis (AIS), a three-dimensional deformity of the spine that includes a coronal curve, vertebral rotation, and flattening of the sagittal profile, affects appropriately 2%–3% adolescents.1-3
A new scoliosis brace padding method based on trunk asymmetry for scoliosis treatment
2023, Prosthetics and Orthotics International
Conflict of interest statement: The publication of this article was supported by funding from 2018YFC0116500, National Key Research and Development Program, 2014B02021202, Guangdong Science and Technology Planning Project, and 31771330, National Natural Science Foundation of China.
Chuandong Lang, Zifang Huang, and Wenyuan Sui contributed equally to the present study.