Straightening the Facts: Early versus Late Adolescent Surgery in Idiopathic Scoliosis

Straightening the Facts: Early versus Late Adolescent Surgery in Idiopathic Scoliosis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Straightening the Facts: Early versus Late Adolescent Surgery in Idiopathic Scoliosis Ji Uk Choi, Choon Sung Lee, Dong-Ho Lee, Jae Hwan Cho, Sehan Park, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5343338/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose: This study aimed to investigate how age at surgery influences outcomes in teenage patients with AIS, addressing the gap in comparative analysis within the adolescent years. Methods: In this retrospective cohort study, patients with AIS who underwent posterior spinal fusion were divided into two groups: <14 years (Y-14) and ≥14 years (O-14). Inclusion criteria were Lenke Type 1A curve, Cobb angle between 45° and 80°, and minimum 2-year follow-up. Radiographic parameters, correction rates, and Scoliosis Research Society-22 (SRS-22) scores were compared. Univariable and multivariable regression analyses were performed to identify factors associated with curve correction rates. Results: The study included 168 patients (Y-14, n=37; O-14, n=131). The Y-14 group demonstrated significantly larger preoperative main thoracic (MT) curves (59.65° vs. 53.29°) and greater curve flexibility (52.88% vs. 46.35%) than the O-14 group. The Y-14 group achieved higher correction rates both immediately after surgery (83.25% vs. 77.49%) and at two-year follow-up (82.28% vs. 75.61%), maintaining more favorable MT curve correction over time (Final follow-up: 10.18° vs. 12.91°). The SRS-22 scores showed no significant differences between groups. In univariable analysis, age, height, weight, MT bending, and flexibility were significantly associated with MT curve correction. Multivariable analysis confirmed age as an independent predictor of correction. Conclusion: Patients who underwent AIS surgery before the age of 14 years demonstrated superior radiographic outcomes and maintained better correction over time than those who underwent the surgery at 14 years or older, while clinical outcomes measured using the SRS-22 scores were similar between the groups. Scoliosis Adolescent Spinal fusion Age factors Treatment outcome Figures Figure 1 Figure 2 Figure 3 INTRODUCTION Determining the optimal timing for surgical intervention in adolescent idiopathic scoliosis (AIS) is crucial in clinical practice. Current evidence strongly supports early surgical intervention for skeletally immature patients with curves exceeding 45° or 50°. This is because delaying surgery in these cases often results in progressive curve magnitude and necessitates more extensive surgical procedures [ 1 – 4 ]. Adolescents typically achieve superior radiographic outcomes with better Cobb angle correction and fewer complications compared to adults undergoing surgery later in life [ 5 – 7 ]. Early intervention during adolescence also correlates with improved postoperative quality of life and functional outcomes [ 6 , 8 ]. Conversely, prolonged wait times for surgery can significantly exacerbate curve progression, potentially requiring more complex interventions and additional surgeries [ 9 , 10 ]. Despite the current clinical recommendations, patients and their families may hesitate to proceed with surgery immediately because of significant concerns and preferences. Concerns regarding neurologic deficits and anticipated postoperative pain are major worries for both parents and patients, influencing the inclination to delay surgery [ 11 ]. Families often weigh these fears against the potential benefits of postponing surgery to a later stage. Furthermore, practical considerations, such as minimizing disruptions to academic and social activities, play a role in the decision to delay surgery, especially in cultural contexts where academic performance is highly valued. The optimal timing for surgical intervention in AIS remains a crucial topic. While the existing literature largely compares outcomes between adolescence and adulthood, there is a notable gap in comparative analysis within the teenage years [ 7 , 12 , 13 ]. Specifically, the impact of age at the time of surgery on radiographic and clinical outcomes post-AIS surgery during adolescence remains inadequately explored. This study aimed to address this gap by investigating how age at surgery influences outcomes in teenage patients with AIS. METHODS Patient Inclusion This retrospective cohort study initially included 185 consecutive patients with AIS who underwent surgery at a single institution between February 2012 and December 2020. The patients were categorized into two groups based on their age at the time of surgery: those younger than 14 years (Y-14) and those aged 14 years or older (O-14). The inclusion criteria were as follows: (A) Lenke Type 1A curve, (B) Cobb angle between 45° and 80°, (C) one-stage posterior spinal fusion with all-pedicle-screw instrumentation, and (D) a minimum of 2 years of follow-up after surgery. The exclusion criteria were inadequate follow-up (n = 3) and insufficient medical records (n = 14), resulting in a final study population of 168 patients (Fig. 1 ). All surgeries were performed by a single surgeon using standard curve correction techniques, including translation and derotation [ 14 ]. This study was approved by the institutional review board of our institution (approval number: S2024-1861). Radiographic Evaluation Preoperative, immediate postoperative, and follow-up radiographs were analyzed. The measured radiographic parameters included the Cobb angle of the main thoracic (MT) and thoracolumbar/lumbar (TL/L) curves, proximal thoracic kyphosis (TK), lumbar lordosis, and radiographic shoulder height (RSH). The correction rate of the MT curve was calculated using the Cobb angles. The preoperative Cobb angle (a) and the postoperative Cobb angle (b) were used in the following equation: Correction Rate = (1 − b/a) × 100. This rate was assessed at multiple postoperative intervals, including immediately postoperative, at the 2-year follow-up, and at the final follow-up, using radiographs taken at each time point. Curve flexibility was evaluated using bending radiographs and calculated by comparing the MT bending Cobb angle to the MT standing Cobb angle. Measurements were conducted using the PACS software (PetaVision for Clinics 2; Asan Medical Center, Seoul, Korea) for consistency and accuracy. Health-Related Quality of Life (HRQoL) Evaluation Clinical outcomes were assessed using the Scoliosis Research Society-22 (SRS-22) questionnaire, which was completed preoperatively, 2 years postoperatively, and at the final follow-up. The parameters included mental health, pain, function, and patient satisfaction. Statistical Analysis Statistical analyses were performed using the SPSS statistical software version 21 (SPSS Inc., Chicago, IL, USA). The Shapiro-Wilk test was used to assess the normality of continuous variables. Between-group comparisons were performed using independent t-test for continuous variables, and chi-square test or Fisher's exact test for categorical variables. Paired t-test was used for comparing preoperative and postoperative measurements within groups. Univariable and multivariable regression analyses were performed to identify factors associated with the curve correction rates. Multicollinearity was assessed using variance inflation factors (VIF). A p-value of < 0.05 was considered statistically significant. RESULTS Demographics A total of 168 patients were included in the study, comprising 37 and 131 patients in the Y-14 and O-14 groups, respectively. Both groups predominantly comprised females, with approximately 94.6% in the Y-14 group and approximately 87% in the O-14 group. Statistically significant differences were observed in height and weight, with the Y-14 group being shorter (154.89 ± 6.55 cm) and having lower body weight (44.53 ± 6.07 kg) than the O-14 group (160.93 ± 7.11 cm and 50.36 ± 8.83 kg, respectively). There were no significant differences in the body mass index, estimated blood loss, or fusion levels between the groups. Moreover, the mean operative time was notably shorter in the Y-14 group (186 min vs. 199 min, p = 0.017) (Table 1). Radiographic Parameters Preoperatively, the Y-14 group had significantly larger MT curves (59.65° vs. 53.29°, p < 0.001) and thoracolumbar/lumbar curves (32.16° vs. 28.34°, p = 0.007) than the O-14 group. The Y-14 group also demonstrated greater main curve flexibility (52.88% vs. 46.35%, p = 0.026) (Table 2). The postoperative radiographs revealed that the Y-14 group had higher correction rates of the MT curve both immediately after surgery (83.25% vs. 77.49%, p < 0.001) and at the 2-year follow-up (82.28% vs. 75.61%, p < 0.001) (Table 2). Over time, the Y-14 group maintained a more favorable MT curve correction at the immediate postoperative, 2-year postoperative, and final postoperative follow-ups (PostOP-Immediate: 8.59° vs. 11.37°, p < 0.001; PostOP-2Y: 9.86° vs. 12.27°, p < 0.001; PostOP-Final: 10.18° vs. 12.91°, p 0.05). At the 2-year follow-up, both groups exhibited significant improvements in their SRS-22 scores. However, the overall change in SRS-22 scores did not differ significantly between the groups, indicating similar improvements in the HRQoL regardless of the timing of surgery (Table 2). Complications The overall complication rate was low and comparable between the two groups. In the Y-14 group, one case of wound dehiscence was reported. In the O-14 group, there were two complications: one case of wound dehiscence and one of superficial surgical site infection. No other major complications, such as neurological deficits or implant-related failures, were observed in either group (Table 1). Factors Affecting MT Curve Correction Univariable and multivariable regression analyses were conducted to identify factors associated with the correction of the MT curve at the final postoperative follow-up (Table 3). In the univariable analysis, age (B = -0.784, p < 0.001), height (B = -0.261, p = 0.007), weight (B = -0.165, p = 0.047), MT bending (B = -0.157, p = 0.031), and flexibility (B = 0.129, p = 0.004) were significantly associated with the MT curve correction (Table 3). In the multivariable analysis, age remained a significant factor influencing the MT curve correction (B = -0.598, p = 0.014), indicating that younger age at the time of surgery was associated with better correction outcomes. Other variables, including flexibility and MT bending, did not maintain statistical significance in the multivariable model (Table 3). DISCUSSION In clinical practice, patients with AIS frequently present with main curves exceeding 45–50°, fulfilling the radiographic criteria for surgical intervention [ 1 – 4 ]. However, despite these indications, there is often hesitation among patients and their families to proceed with surgery. Concerns about potential complications, interruptions to academic schedules, and social perceptions contribute to this reluctance[ 11 ]. Additionally, as many of these patients are asymptomatic (aside from deformity), there is a strong inclination to delay surgical intervention [ 15 , 16 ]. This study aimed to provide data that could assist in determining the optimal timing of surgery by comparing outcomes between patients undergoing surgery in early versus late adolescence. We divided the patients into early and late adolescence groups to compare postoperative outcomes, offering potentially greater clinical utility than in previous studies that primarily compared adolescence with adulthood. In clinical practice, patients in the early adolescence stage often consider delaying surgery until after completing university entrance exams or during their first year of college. The decision to use 14 years as the cutoff was based on several factors. First, the average age of menarche in Korea is around 12.6–12.7 years and has been gradually decreasing over time [ 17 , 18 ]. Moreover, spinal growth in females usually persists for a few years post-menarche. One study revealed that the lumbar bone mineral content reaches approximately 85% of its adult value 2 years post-menarche, with no further significant changes observed 7 years afterward [ 19 ]. Another study indicated that growth of the lumbar spine and femoral neck in females significantly slows down between the second and fourth years post-menarche [ 20 ]. Additionally, in the Korean education system, 14 years corresponds to the second year of middle school, representing a transitional period in the elementary, middle, and high school progression. Our findings demonstrate that patients who underwent surgery in early adolescence (Y-14) exhibited superior radiographic outcomes than those who had surgery later (O-14). This difference is illustrated in Fig. 3 , which compares the radiographic outcomes between a 12-year-old female patient (Y-14 group) and a 19-year-old male patient (O-14 group). The Y-14 group presented with significantly greater main curve flexibility preoperatively, leading to higher correction rates both immediately postoperatively and at the 2-year follow-up. These results align with the existing literature suggesting that surgical intervention before skeletal maturity can lead to improved correction due to the greater spinal flexibility in younger patients [ 1 , 2 , 6 , 7 ]. Radiographic progression of scoliosis correction in the early and late adolescent patients. (a–d) Female patient who underwent surgery at 12 years old: a. Preoperative, b. Immediate postoperative, c. 2-year postoperative, d. 5-year postoperative. (e–h) Male patient who underwent surgery at 19 years old: e. Preoperative, f. Immediate postoperative, g. 2-year postoperative, h. 5-year postoperative. Numbers indicate the main thoracic Cobb angles (in degrees) and correction rates (in percentages) at each time point. Note the superior and sustained correction in the younger patient (a–d) compared to the gradual loss of correction in the older patient (e–h). Preoperatively, the Y-14 group had larger MT and thoracolumbar/lumbar curves than the O-14 group; however, it demonstrated greater flexibility. This flexibility likely contributed to the higher correction rates observed postoperatively in the Y-14 group. These findings highlight the importance of surgical timing in AIS management, as younger patients' spines are more amenable to correction [ 5 ]. Moreover, the Y-14 group maintained these superior correction rates over time, as evidenced by consistent outcomes across the immediate, 2-year, and final follow-up points. The diminished flexibility in older adolescents may explain the lower correction rates in the O-14 group, indicating that surgical delay could potentially compromise the optimal radiographic outcomes. Although the radiographic outcomes differed significantly between the groups, the SRS-22 clinical outcomes were similar. Both the Y-14 and O-14 groups showed substantial improvements at the 2-year follow-up, suggesting that the benefits of surgery in terms of HRQoL can be achieved regardless of the timing within the adolescent period. These findings indicate that while earlier surgery may result in better radiographic correction, the overall postoperative quality of life is comparable between the two age groups. This suggests that factors beyond radiographic correction, such as psychosocial factors and body image disturbances, play a crucial role in perceived postoperative well-being [ 8 , 21 ]. The regression analysis revealed age as a significant predictor of MT curve correction rates. In particular, younger age at the time of surgery was associated with higher correction rates, even after controlling for other variables in the multivariate model. This finding emphasizes the critical role of early surgical intervention, suggesting that the inherent flexibility of the younger spine significantly contributes to superior postoperative outcomes. The diminished flexibility observed in older adolescents may limit the extent of correction achievable during surgery, reinforcing the importance of timely interventions. While factors such as height and weight were significant in the univariate analysis, they lost their significance in the multivariate model, indicating that age is a more direct and influential factor on correction outcomes. These results underscore the importance of considering patient age when planning surgical interventions for AIS, as earlier surgery can maximize radiographic correction by leveraging the natural flexibility of the younger spine. The low and comparable complication rates between the Y-14 and O-14 groups provide valuable clinical insights. This suggests that the timing of surgical intervention within adolescence, whether early or late, does not significantly increase the overall risk of postoperative complications, offering reassurance for patients and clinicians during this critical developmental period. However, it is important to note that other studies have reported higher complication rates associated with delayed surgery. For example, Ahn et al. demonstrated that patients who waited longer than 6 months for AIS surgery had a higher likelihood of requiring additional procedures due to curve progression and faced increased risks of prolonged surgery, increased blood loss, and suboptimal correction [ 9 ]. The progression of spinal curvature with extended waiting periods can lead to a more complex surgical process and an elevated risk of complications. Clinically, this underscores the potential benefits of earlier surgical intervention, not only to improve radiographic outcomes but also to mitigate the risk of additional procedures and complications associated with delayed surgery. Therefore, while individualized preoperative counseling is crucial, this study supports the notion that early surgery may offer a more favorable risk-benefit balance for patients with AIS, potentially reducing the need for more extensive procedures and the associated complications over time. This study had several limitations that warrant consideration. As a retrospective study, it was subject to selection and recall bias, which may have affected the accuracy and reliability of the data. Additionally, the relatively small sample size, particularly in the Y-14 group, reduced the statistical power to detect subtle differences between the groups, and this may limit the generalizability of the findings. Another limitation is the study's design, which involved comparing different patient cohorts who underwent surgery at different ages rather than assessing early versus delayed surgery within the same cohort. This may have introduced heterogeneity owing to individual variations, such as curve progression rates and growth patterns. Despite these limitations, the study possesses notable strengths. By specifically focusing on Lenke Type 1A curves, we ensured a more homogeneous patient population, thereby reducing variability and enhancing the interpretability of the results. Furthermore, although the comparative design has its drawbacks, it accurately reflects a real-world clinical scenario. Unlike previous studies that primarily compared outcomes between adolescence and adulthood, this study provides a more detailed analysis of the surgical timing within the adolescent period. This distinction offers practical insights for clinicians and families considering the timing of surgical intervention in adolescents with AIS. In conclusion, this study emphasizes the critical importance of surgical timing in the management of AIS. While clinical outcomes measured by HRQoL scores showed no significant differences between the age groups, patients undergoing surgery in early adolescence demonstrated superior radiographic outcomes. This improved radiographic correction is attributed to increased spinal flexibility in younger patients. These findings provide valuable clinical guidance for surgical decision-making in AIS treatment, suggesting that intervention during early adolescence may be considered as a preferred strategy to maximize radiographic correction while maintaining satisfactory clinical outcomes. Declarations Author Contribution Conceptualization, J.U.C., C.S.L., and C.J.H.; methodology, J.U.C. and S.P.; software, not applicable; validation, J.U.C., D.H.L., C.J.H., and J.H.C.; formal analysis, J.U.C.; investigation, J.U.C. and M.J.; resources, C.J.H. and C.S.L.; data curation, J.U.C. and M.J.; writing—original draft preparation, J.U.C.; writing—review and editing, J.U.C., S.P., and J.H.C.; visualization, J.U.C.; supervision, C.S.L., D.H.L. and C.J.H. All authors have read and agreed to the published version of the manuscript. Acknowledgement The authors express their gratitude to Seonohk Ji for her support in data collection. Data Availability The data supporting the findings of this study are not publicly available due to privacy and ethical restrictions. However, de-identified datasets are available from the corresponding author upon reasonable request, subject to approval by the Institutional Review Board of Asan Medical Center. 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Summary of the Data regarding the Younger-14 and 14-and-Older Groups Y-14 (n=37) O-14 (n=131) p-value Female 35 (94.6%) 114 (87%) 0.117 Height (cm) 154.89 ± 6.55* 160.93 ± 7.11* <0.001 Weight (kg) 44.53 ± 6.07* 50.36 ± 8.83* <0.001 BMI (kg/m 2 ) 18.56 ± 2.28 19.41 ± 2.92 0.103 EBL (mL) 809.62 ± 502.80 805.5 ± 595.56 0.974 OP time 3:06:50 ± 0:28:32* 3:19:23 ± 0:27:42* 0.017 LOS (days) 12.14 ± 1.08 12.16 ± 1.63 0.93 Fusion levels 10.41 ± 1.28 10.53 ± 1.36 0.627 Complication 1 (2.7%) 2 (1.5%) 0.633 UIV T2 5 (13.5%) 17 (13%) 0.208 T3 4 (10.8%) 29 (22.1%) T4 22 (59.5%) 75 (57.3%) T5 6 (16.2%) 7 (5.3%) T6 0 (0%) 1 (0.8%) T8 0 (0%) 2 (1.5%) LIV T12 1 (2.7%) 4 (3.1%) 0.381 L1 10 (27%) 38 (29%) L2 20 (54.1%) 52 (39.7%) L3 6 (16.2%) 4 (3.1%) Data represent the mean ± standard deviation values. Significant differences are accepted for *p-values < 0.05. BMI, body mass index; EBL, estimated blood loss; OP, operation; LOS, lengths of stay; UIV, uppermost instrumented vertebra; LIV, lowest instrumented vertebra. Table 2 . Summary of the Radiographic & Clinical Parameters of the Younger-14 and 14-and-Older Groups Variables Y-14 (n=37) O-14 (n=131) p-value Spinal alignment Mean ± SD Proximal TK (°) 10.81 ± 6.56 9.89 ± 5.88 0.415 Distal TK (°) 11.11 ± 8.34 10.53 ± 8.63 0.719 TL/L Lordosis (°) -0.22 ± 7.24 -2.22 ± 13.17 0.376 Lumbar Lordosis (°) -50.59 ± 10.34 -49.44 ± 10.44 0.551 RSH (mm) 18.51 ± 13.54* 13.43 ± 11.85* 0.027 C7-CSVL (mm) 4.3 ± 16.21 2.81 ± 11.88 0.605 Preoperative PT (standing) (°) Cobb angle 26.35 ± 6.64 24.88 ± 7.35 0.274 PT (prone) (°) 22.27 ± 7.05 21.43 ± 6.62 0.501 PT (bending) (°) 18.41 ± 6.73 17.63 ± 6.81 0.539 MT (standing) (°) 59.65 ± 8.01* 53.29 ± 6.77* <0.001 MT (prone) (°) 39.08 ± 7.19 37.71 ± 7.63 0.33 MT (bending) (°) 27.95 ± 10.26 28.77 ± 9.79 0.655 TL/L (standing) (°) 32.16 ± 7.46* 28.34 ± 7.44* 0.007 TL/L (prone) (°) 19.70 ± 5.75 19.53 ± 7.54 0.9 TL/L (bending) (°) 12.08 ± 7.03 11.59 ± 7.00 0.706 Main Curve Flexibility (%) 52.88 ± 16.49* 46.35 ± 15.32* 0.026 Postoperative MT imPO (°) Cobb angle 9.95 ± 4.384* 12.04 ± 5.121* 0.025 MT 2YPO (°) 10.64 ± 4.241* 13.1 ± 5.381* 0.016 MT FinalPO (°) 10.54 ± 4.273 12.61 ± 5.382 0.072 Perioperative change △MT imPO (%) 83.25 ± 7.01* 77.49 ± 9.09* <0.001 △MT 2YPO (%) 82.28 ± 6.44* 75.61 ± 9.52* <0.001 △MT finalPO (%) 81.49 ± 6.49* 75.16 ± 9.5* <0.001 SRS22 score PreOP 2.90 ± 0.72 2.86 ± 0.57 0.777 PostOP-2Y 2.20 ± 0.27 2.24 ± 0.23 0.516 PostOP-Final 2.18 ± 0.27 2.26 ± 0.25 0.117 △SRS22 Final 0.7 ± 0.72 0.54 ± 0.57 0.251 Data represent the mean ± standard deviation values. Significant differences are accepted for *p-values < 0.05. TK, thoracic kyphosis; TL/L, thoracolumbar/lumbar; RSH, radiographic shoulder height; CSVL, central sacral vertical line; PT, proximal thoracic; MT, main thoracic; imPO, immediate postoperative; 2YPO, 2-year postoperative; finalPO, final postoperative; SRS-22, Scoliosis Research Society-22 questionnaire; PreOP, preoperative; PostOP, postoperative Table 3 . Results of the Univariate and Multivariate Regression Analysis Indicating the Factors Associated With the Correction of the Main Thoracic Curve at the Final Postoperative Follow-up Univariable analysis Multivariable analysis Variables B (95% CI) p-value B (95% CI) p-value Age -0.784 (-1.221, -0.348) * <0.001 -0.598 (-1.072, -0.124) * 0.014 Female 2.682 (-1.649, 7.012) 0.223 Height -0.261 (-0.449, -0.074) * 0.007 -0.109 (-0.337, 0.119) 0.346 Weight -0.165 (-0.328, -0.002) * 0.047 -0.051 (-0.247, 0.146) 0.611 BMI -0.129 (-0.636, 0.377) 0.614 PT (standing) CA 0.111 (-0.085, 0.308) 0.265 PT (prone) -0.059 (-0.271, 0.153) 0.582 PT (bending) 0.022 (-0.187, 0.232) 0.833 MT (standing) 0.082 (-0.107, 0.271) 0.391 MT (prone) -0.162 (-0.349, 0.025) 0.089 MT (bending) -0.157 (-0.299, -0.014) * 0.031 0.007 (-0.245, 0.606) 0.965 TL/L (standing) 0.033 (-0.155, 0.220) 0.732 TL/L (prone) -0.132 (-0.330, 0.065) 0.187 TL/L (bending) -0.073 (-0.276, 0.131) 0.482 Rotation Apex (MT) 0.030 (-0.269, 0.328) 0.845 Rotation Apex (TL/L) 0.222 (-0.012, 0.457) 0.063 RSH 0.016 (-0.099, 0.131) 0.789 C7-CSVL 0.094 (-0.015, 0.203) 0.091 Proximal TK 0.110 (-0.126, 0.346) 0.358 Distal TK -0.032 (-0.198, 0.135) 0.709 TL/L Lordosis 0.005 (-0.113, 0.122) 0.934 Lumbar Lordosis 0.120 (-0.016, 0.255) 0.084 Flexibility 0.129 (0.040, 0.217) * 0.004 0.107 (-0.102, 0.315) 0.314 Significant differences are accepted for *p-values < 0.05. BMI, body mass index; PT, proximal thoracic curve; CA, Cobb angle; MT, main thoracic curve; TL/L, thoracolumbar/lumbar curve; RSH, radiographic shoulder height; CSVL, central sacral vertical line; TK, thoracic kyphosis; CI, confidence interval Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5343338","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":372237758,"identity":"d1055f3c-edc8-45e5-ac0f-1496310f1c3c","order_by":0,"name":"Ji Uk Choi","email":"","orcid":"","institution":"Asan Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Ji","middleName":"Uk","lastName":"Choi","suffix":""},{"id":372237759,"identity":"0bb552ad-d870-4627-9fbd-361427880e6a","order_by":1,"name":"Choon Sung Lee","email":"","orcid":"","institution":"Gangnam Saint Peter’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Choon","middleName":"Sung","lastName":"Lee","suffix":""},{"id":372237760,"identity":"7f481fed-35d1-4c7b-a6f5-e91c07d67b45","order_by":2,"name":"Dong-Ho Lee","email":"","orcid":"","institution":"Asan Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Dong-Ho","middleName":"","lastName":"Lee","suffix":""},{"id":372237761,"identity":"08b15216-2074-4661-a9d8-fbaab9b9ad90","order_by":3,"name":"Jae Hwan Cho","email":"","orcid":"","institution":"Asan Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Jae","middleName":"Hwan","lastName":"Cho","suffix":""},{"id":372237762,"identity":"99c1b8cb-c146-457a-a192-110083f1ee91","order_by":4,"name":"Sehan Park","email":"","orcid":"","institution":"Asan Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Sehan","middleName":"","lastName":"Park","suffix":""},{"id":372237763,"identity":"e2eaab24-13de-4700-a607-6ff9a8b56623","order_by":5,"name":"Mingeol Je","email":"","orcid":"","institution":"Asan Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Mingeol","middleName":"","lastName":"Je","suffix":""},{"id":372237764,"identity":"e3b0fc09-0577-4761-a888-eadbcf688e74","order_by":6,"name":"Chang Ju Hwang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAyklEQVRIiWNgGAWjYBACAwYGZoYEnv9yIM6BB8RrkWE2BmtJIFoLgw1zYgOIR5QWc/bjjw0e5LClzw87/BBoi52cbgMBLZY9OcYJCWd4cjfeTjMAakk2NjtAyGEHcpgPJPZI5G6cnQDSciBxG0Et558/PpD4zyDdcHb6ByK13EgAOownIUFeOodIWyxnvDE2SOA5YLhBOqfgQIIBEX4x509/LPmD54C8/Oz0zR8+VNjJEdSCcCFYpQGxykFAvoEU1aNgFIyCUTCiAABkJEbZ1Ktr3QAAAABJRU5ErkJggg==","orcid":"","institution":"Asan Medical Center","correspondingAuthor":true,"prefix":"","firstName":"Chang","middleName":"Ju","lastName":"Hwang","suffix":""}],"badges":[],"createdAt":"2024-10-28 02:08:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5343338/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5343338/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":69911400,"identity":"dcebd9ec-c8e0-4734-b97d-90a76dcb8f47","added_by":"auto","created_at":"2024-11-26 13:53:59","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":37661,"visible":true,"origin":"","legend":"\u003cp\u003ePatient Selection and Group Allocation Flowchart\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5343338/v1/a9197df4fb7e08cc5e4b7b3a.png"},{"id":69911403,"identity":"56071bfe-146c-47a8-a06c-576bf0893ff4","added_by":"auto","created_at":"2024-11-26 13:54:00","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":25603,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparison of the Main Thoracic Curve Changes Over Time in the Younger-14 and 14-and-Older Groups Significant differences are accepted for †P-values \u0026lt; 0.05\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5343338/v1/280795abd911b9f371366f18.png"},{"id":69911402,"identity":"fe0fb555-26d4-4f88-9bf7-fef73e140c6b","added_by":"auto","created_at":"2024-11-26 13:54:00","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":493933,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of the Radiographic Outcomes in the Patients with Early vs. Late Adolescent Idiopathic\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5343338/v1/eed1313f81b1e30978c35cbd.png"},{"id":69912372,"identity":"92f689bd-316f-402a-bc02-17e7ca3c10f9","added_by":"auto","created_at":"2024-11-26 14:02:05","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1252307,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5343338/v1/f7b4a80b-1d9a-4b31-8b4f-be670f4b45fe.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Straightening the Facts: Early versus Late Adolescent Surgery in Idiopathic Scoliosis","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eDetermining the optimal timing for surgical intervention in adolescent idiopathic scoliosis (AIS) is crucial in clinical practice. Current evidence strongly supports early surgical intervention for skeletally immature patients with curves exceeding 45\u0026deg; or 50\u0026deg;. This is because delaying surgery in these cases often results in progressive curve magnitude and necessitates more extensive surgical procedures [\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Adolescents typically achieve superior radiographic outcomes with better Cobb angle correction and fewer complications compared to adults undergoing surgery later in life [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Early intervention during adolescence also correlates with improved postoperative quality of life and functional outcomes [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Conversely, prolonged wait times for surgery can significantly exacerbate curve progression, potentially requiring more complex interventions and additional surgeries [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDespite the current clinical recommendations, patients and their families may hesitate to proceed with surgery immediately because of significant concerns and preferences. Concerns regarding neurologic deficits and anticipated postoperative pain are major worries for both parents and patients, influencing the inclination to delay surgery [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Families often weigh these fears against the potential benefits of postponing surgery to a later stage. Furthermore, practical considerations, such as minimizing disruptions to academic and social activities, play a role in the decision to delay surgery, especially in cultural contexts where academic performance is highly valued.\u003c/p\u003e \u003cp\u003eThe optimal timing for surgical intervention in AIS remains a crucial topic. While the existing literature largely compares outcomes between adolescence and adulthood, there is a notable gap in comparative analysis within the teenage years [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Specifically, the impact of age at the time of surgery on radiographic and clinical outcomes post-AIS surgery during adolescence remains inadequately explored. This study aimed to address this gap by investigating how age at surgery influences outcomes in teenage patients with AIS.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatient Inclusion\u003c/h2\u003e \u003cp\u003eThis retrospective cohort study initially included 185 consecutive patients with AIS who underwent surgery at a single institution between February 2012 and December 2020. The patients were categorized into two groups based on their age at the time of surgery: those younger than 14 years (Y-14) and those aged 14 years or older (O-14). The inclusion criteria were as follows: (A) Lenke Type 1A curve, (B) Cobb angle between 45\u0026deg; and 80\u0026deg;, (C) one-stage posterior spinal fusion with all-pedicle-screw instrumentation, and (D) a minimum of 2 years of follow-up after surgery. The exclusion criteria were inadequate follow-up (n\u0026thinsp;=\u0026thinsp;3) and insufficient medical records (n\u0026thinsp;=\u0026thinsp;14), resulting in a final study population of 168 patients (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). All surgeries were performed by a single surgeon using standard curve correction techniques, including translation and derotation [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e This study was approved by the institutional review board of our institution (approval number: S2024-1861).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eRadiographic Evaluation\u003c/h3\u003e\n\u003cp\u003ePreoperative, immediate postoperative, and follow-up radiographs were analyzed. The measured radiographic parameters included the Cobb angle of the main thoracic (MT) and thoracolumbar/lumbar (TL/L) curves, proximal thoracic kyphosis (TK), lumbar lordosis, and radiographic shoulder height (RSH). The correction rate of the MT curve was calculated using the Cobb angles. The preoperative Cobb angle (a) and the postoperative Cobb angle (b) were used in the following equation:\u003c/p\u003e \u003cp\u003eCorrection Rate = (1\u0026thinsp;\u0026minus;\u0026thinsp;b/a) \u0026times; 100.\u003c/p\u003e \u003cp\u003eThis rate was assessed at multiple postoperative intervals, including immediately postoperative, at the 2-year follow-up, and at the final follow-up, using radiographs taken at each time point. Curve flexibility was evaluated using bending radiographs and calculated by comparing the MT bending Cobb angle to the MT standing Cobb angle.\u003c/p\u003e \u003cp\u003eMeasurements were conducted using the PACS software (PetaVision for Clinics 2; Asan Medical Center, Seoul, Korea) for consistency and accuracy.\u003c/p\u003e\n\u003ch3\u003eHealth-Related Quality of Life (HRQoL) Evaluation\u003c/h3\u003e\n\u003cp\u003eClinical outcomes were assessed using the Scoliosis Research Society-22 (SRS-22) questionnaire, which was completed preoperatively, 2 years postoperatively, and at the final follow-up. The parameters included mental health, pain, function, and patient satisfaction.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eStatistical analyses were performed using the SPSS statistical software version 21 (SPSS Inc., Chicago, IL, USA). The Shapiro-Wilk test was used to assess the normality of continuous variables. Between-group comparisons were performed using independent t-test for continuous variables, and chi-square test or Fisher's exact test for categorical variables. Paired t-test was used for comparing preoperative and postoperative measurements within groups. Univariable and multivariable regression analyses were performed to identify factors associated with the curve correction rates. Multicollinearity was assessed using variance inflation factors (VIF). A p-value of \u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eDemographics\u003c/h2\u003e \u003cp\u003eA total of 168 patients were included in the study, comprising 37 and 131 patients in the Y-14 and O-14 groups, respectively. Both groups predominantly comprised females, with approximately 94.6% in the Y-14 group and approximately 87% in the O-14 group. Statistically significant differences were observed in height and weight, with the Y-14 group being shorter (154.89\u0026thinsp;\u0026plusmn;\u0026thinsp;6.55 cm) and having lower body weight (44.53\u0026thinsp;\u0026plusmn;\u0026thinsp;6.07 kg) than the O-14 group (160.93\u0026thinsp;\u0026plusmn;\u0026thinsp;7.11 cm and 50.36\u0026thinsp;\u0026plusmn;\u0026thinsp;8.83 kg, respectively). There were no significant differences in the body mass index, estimated blood loss, or fusion levels between the groups. Moreover, the mean operative time was notably shorter in the Y-14 group (186 min vs. 199 min, p\u0026thinsp;=\u0026thinsp;0.017) (Table\u0026nbsp;1).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eRadiographic Parameters\u003c/h3\u003e\n\u003cp\u003ePreoperatively, the Y-14 group had significantly larger MT curves (59.65\u0026deg; vs. 53.29\u0026deg;, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and thoracolumbar/lumbar curves (32.16\u0026deg; vs. 28.34\u0026deg;, p\u0026thinsp;=\u0026thinsp;0.007) than the O-14 group. The Y-14 group also demonstrated greater main curve flexibility (52.88% vs. 46.35%, p\u0026thinsp;=\u0026thinsp;0.026) (Table\u0026nbsp;2). The postoperative radiographs revealed that the Y-14 group had higher correction rates of the MT curve both immediately after surgery (83.25% vs. 77.49%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and at the 2-year follow-up (82.28% vs. 75.61%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;2). Over time, the Y-14 group maintained a more favorable MT curve correction at the immediate postoperative, 2-year postoperative, and final postoperative follow-ups (PostOP-Immediate: 8.59\u0026deg; vs. 11.37\u0026deg;, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001; PostOP-2Y: 9.86\u0026deg; vs. 12.27\u0026deg;, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001; PostOP-Final: 10.18\u0026deg; vs. 12.91\u0026deg;, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eClinical Outcomes\u003c/h3\u003e\n\u003cp\u003eThe preoperative SRS-22 scores showed no significant differences between the Y-14 and O-14 groups in terms of mental health, pain, or function (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). At the 2-year follow-up, both groups exhibited significant improvements in their SRS-22 scores. However, the overall change in SRS-22 scores did not differ significantly between the groups, indicating similar improvements in the HRQoL regardless of the timing of surgery (Table\u0026nbsp;2).\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eComplications\u003c/h2\u003e \u003cp\u003eThe overall complication rate was low and comparable between the two groups. In the Y-14 group, one case of wound dehiscence was reported. In the O-14 group, there were two complications: one case of wound dehiscence and one of superficial surgical site infection. No other major complications, such as neurological deficits or implant-related failures, were observed in either group (Table\u0026nbsp;1).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eFactors Affecting MT Curve Correction\u003c/h2\u003e \u003cp\u003eUnivariable and multivariable regression analyses were conducted to identify factors associated with the correction of the MT curve at the final postoperative follow-up (Table\u0026nbsp;3). In the univariable analysis, age (B = -0.784, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), height (B = -0.261, p\u0026thinsp;=\u0026thinsp;0.007), weight (B = -0.165, p\u0026thinsp;=\u0026thinsp;0.047), MT bending (B = -0.157, p\u0026thinsp;=\u0026thinsp;0.031), and flexibility (B\u0026thinsp;=\u0026thinsp;0.129, p\u0026thinsp;=\u0026thinsp;0.004) were significantly associated with the MT curve correction (Table\u0026nbsp;3).\u003c/p\u003e \u003cp\u003eIn the multivariable analysis, age remained a significant factor influencing the MT curve correction (B = -0.598, p\u0026thinsp;=\u0026thinsp;0.014), indicating that younger age at the time of surgery was associated with better correction outcomes. Other variables, including flexibility and MT bending, did not maintain statistical significance in the multivariable model (Table\u0026nbsp;3).\u003c/p\u003e \u003c/div\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eIn clinical practice, patients with AIS frequently present with main curves exceeding 45\u0026ndash;50\u0026deg;, fulfilling the radiographic criteria for surgical intervention [\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. However, despite these indications, there is often hesitation among patients and their families to proceed with surgery. Concerns about potential complications, interruptions to academic schedules, and social perceptions contribute to this reluctance[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Additionally, as many of these patients are asymptomatic (aside from deformity), there is a strong inclination to delay surgical intervention [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. This study aimed to provide data that could assist in determining the optimal timing of surgery by comparing outcomes between patients undergoing surgery in early versus late adolescence.\u003c/p\u003e \u003cp\u003eWe divided the patients into early and late adolescence groups to compare postoperative outcomes, offering potentially greater clinical utility than in previous studies that primarily compared adolescence with adulthood. In clinical practice, patients in the early adolescence stage often consider delaying surgery until after completing university entrance exams or during their first year of college. The decision to use 14 years as the cutoff was based on several factors. First, the average age of menarche in Korea is around 12.6\u0026ndash;12.7 years and has been gradually decreasing over time [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Moreover, spinal growth in females usually persists for a few years post-menarche. One study revealed that the lumbar bone mineral content reaches approximately 85% of its adult value 2 years post-menarche, with no further significant changes observed 7 years afterward [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Another study indicated that growth of the lumbar spine and femoral neck in females significantly slows down between the second and fourth years post-menarche [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Additionally, in the Korean education system, 14 years corresponds to the second year of middle school, representing a transitional period in the elementary, middle, and high school progression.\u003c/p\u003e \u003cp\u003eOur findings demonstrate that patients who underwent surgery in early adolescence (Y-14) exhibited superior radiographic outcomes than those who had surgery later (O-14). This difference is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, which compares the radiographic outcomes between a 12-year-old female patient (Y-14 group) and a 19-year-old male patient (O-14 group). The Y-14 group presented with significantly greater main curve flexibility preoperatively, leading to higher correction rates both immediately postoperatively and at the 2-year follow-up. These results align with the existing literature suggesting that surgical intervention before skeletal maturity can lead to improved correction due to the greater spinal flexibility in younger patients [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eRadiographic progression of scoliosis correction in the early and late adolescent patients. (a\u0026ndash;d) Female patient who underwent surgery at 12 years old: a. Preoperative, b. Immediate postoperative, c. 2-year postoperative, d. 5-year postoperative. (e\u0026ndash;h) Male patient who underwent surgery at 19 years old: e. Preoperative, f. Immediate postoperative, g. 2-year postoperative, h. 5-year postoperative. Numbers indicate the main thoracic Cobb angles (in degrees) and correction rates (in percentages) at each time point. Note the superior and sustained correction in the younger patient (a\u0026ndash;d) compared to the gradual loss of correction in the older patient (e\u0026ndash;h).\u003c/p\u003e \u003cp\u003ePreoperatively, the Y-14 group had larger MT and thoracolumbar/lumbar curves than the O-14 group; however, it demonstrated greater flexibility. This flexibility likely contributed to the higher correction rates observed postoperatively in the Y-14 group. These findings highlight the importance of surgical timing in AIS management, as younger patients' spines are more amenable to correction [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Moreover, the Y-14 group maintained these superior correction rates over time, as evidenced by consistent outcomes across the immediate, 2-year, and final follow-up points. The diminished flexibility in older adolescents may explain the lower correction rates in the O-14 group, indicating that surgical delay could potentially compromise the optimal radiographic outcomes.\u003c/p\u003e \u003cp\u003eAlthough the radiographic outcomes differed significantly between the groups, the SRS-22 clinical outcomes were similar. Both the Y-14 and O-14 groups showed substantial improvements at the 2-year follow-up, suggesting that the benefits of surgery in terms of HRQoL can be achieved regardless of the timing within the adolescent period. These findings indicate that while earlier surgery may result in better radiographic correction, the overall postoperative quality of life is comparable between the two age groups. This suggests that factors beyond radiographic correction, such as psychosocial factors and body image disturbances, play a crucial role in perceived postoperative well-being [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe regression analysis revealed age as a significant predictor of MT curve correction rates. In particular, younger age at the time of surgery was associated with higher correction rates, even after controlling for other variables in the multivariate model. This finding emphasizes the critical role of early surgical intervention, suggesting that the inherent flexibility of the younger spine significantly contributes to superior postoperative outcomes. The diminished flexibility observed in older adolescents may limit the extent of correction achievable during surgery, reinforcing the importance of timely interventions. While factors such as height and weight were significant in the univariate analysis, they lost their significance in the multivariate model, indicating that age is a more direct and influential factor on correction outcomes. These results underscore the importance of considering patient age when planning surgical interventions for AIS, as earlier surgery can maximize radiographic correction by leveraging the natural flexibility of the younger spine.\u003c/p\u003e \u003cp\u003eThe low and comparable complication rates between the Y-14 and O-14 groups provide valuable clinical insights. This suggests that the timing of surgical intervention within adolescence, whether early or late, does not significantly increase the overall risk of postoperative complications, offering reassurance for patients and clinicians during this critical developmental period. However, it is important to note that other studies have reported higher complication rates associated with delayed surgery. For example, Ahn et al. demonstrated that patients who waited longer than 6 months for AIS surgery had a higher likelihood of requiring additional procedures due to curve progression and faced increased risks of prolonged surgery, increased blood loss, and suboptimal correction [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The progression of spinal curvature with extended waiting periods can lead to a more complex surgical process and an elevated risk of complications. Clinically, this underscores the potential benefits of earlier surgical intervention, not only to improve radiographic outcomes but also to mitigate the risk of additional procedures and complications associated with delayed surgery. Therefore, while individualized preoperative counseling is crucial, this study supports the notion that early surgery may offer a more favorable risk-benefit balance for patients with AIS, potentially reducing the need for more extensive procedures and the associated complications over time.\u003c/p\u003e \u003cp\u003eThis study had several limitations that warrant consideration. As a retrospective study, it was subject to selection and recall bias, which may have affected the accuracy and reliability of the data. Additionally, the relatively small sample size, particularly in the Y-14 group, reduced the statistical power to detect subtle differences between the groups, and this may limit the generalizability of the findings. Another limitation is the study's design, which involved comparing different patient cohorts who underwent surgery at different ages rather than assessing early versus delayed surgery within the same cohort. This may have introduced heterogeneity owing to individual variations, such as curve progression rates and growth patterns.\u003c/p\u003e \u003cp\u003eDespite these limitations, the study possesses notable strengths. By specifically focusing on Lenke Type 1A curves, we ensured a more homogeneous patient population, thereby reducing variability and enhancing the interpretability of the results. Furthermore, although the comparative design has its drawbacks, it accurately reflects a real-world clinical scenario. Unlike previous studies that primarily compared outcomes between adolescence and adulthood, this study provides a more detailed analysis of the surgical timing within the adolescent period. This distinction offers practical insights for clinicians and families considering the timing of surgical intervention in adolescents with AIS.\u003c/p\u003e \u003cp\u003eIn conclusion, this study emphasizes the critical importance of surgical timing in the management of AIS. While clinical outcomes measured by HRQoL scores showed no significant differences between the age groups, patients undergoing surgery in early adolescence demonstrated superior radiographic outcomes. This improved radiographic correction is attributed to increased spinal flexibility in younger patients. These findings provide valuable clinical guidance for surgical decision-making in AIS treatment, suggesting that intervention during early adolescence may be considered as a preferred strategy to maximize radiographic correction while maintaining satisfactory clinical outcomes.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eConceptualization, J.U.C., C.S.L., and C.J.H.; methodology, J.U.C. and S.P.; software, not applicable; validation, J.U.C., D.H.L., C.J.H., and J.H.C.; formal analysis, J.U.C.; investigation, J.U.C. and M.J.; resources, C.J.H. and C.S.L.; data curation, J.U.C. and M.J.; writing\u0026mdash;original draft preparation, J.U.C.; writing\u0026mdash;review and editing, J.U.C., S.P., and J.H.C.; visualization, J.U.C.; supervision, C.S.L., D.H.L. and C.J.H. All authors have read and agreed to the published version of the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThe authors express their gratitude to Seonohk Ji for her support in data collection.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data supporting the findings of this study are not publicly available due to privacy and ethical restrictions. However, de-identified datasets are available from the corresponding author upon reasonable request, subject to approval by the Institutional Review Board of Asan Medical Center. The data will be shared in accordance with the principles of FAIR (Findable, Accessible, Interoperable, and Reusable) data practices while ensuring compliance with ethical guidelines and participant confidentiality.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eYang JH, Bhandarkar AW, Rathanvelu B, Choi JY, Suh SW, Hong JY, Modi HN (2014) Does delaying surgery in immature adolescent idiopathic scoliosis patients with progressive curve, lead to addition of fusion levels? Eur Spine J 23(12):2672-2679. https://doi.org/10.1007/s00586-014-3460-2\u003c/li\u003e\n\u003cli\u003eAgabegi SS, Kazemi N, Sturm PF, Mehlman CT (2015) Natural History of Adolescent Idiopathic Scoliosis in Skeletally Mature Patients: A Critical Review. J Am Acad Orthop Surg 23(12):714-723. https://doi.org/10.5435/JAAOS-D-14-00037\u003c/li\u003e\n\u003cli\u003eWeinstein SL, Dolan LA, Cheng JC, Danielsson A, Morcuende JA (2008) Adolescent idiopathic scoliosis. Lancet 371(9623):1527-1537. https://doi.org/10.1016/S0140-6736(08)60658-3\u003c/li\u003e\n\u003cli\u003eKim H, Chang BS, Chang SY (2024) Current issues in the treatment of adolescent idiopathic scoliosis: a comprehensive narrative review. Asian Spine J [Epub ahead of print]. https://doi.org/10.31616/asj.2024.0367\u003c/li\u003e\n\u003cli\u003eChen JW, Chanbour H, Gupta R, Abotsi EJ, Alvarado E, Yang JS, Cho W (2024) Adult versus adolescent idiopathic scoliosis surgery: a meta-analysis of clinical and radiographic outcomes. Eur Spine J 33(4):1637-1643. https://doi.org/10.1007/s00586-023-07974-0\u003c/li\u003e\n\u003cli\u003eStencel-Allemand M, Marie-Hardy L, Khalife M, Pernin J, Miladi L, Ilharreborde B (2024) A comparison of idiopathic scoliosis surgery between teenage years and adulthood. Eur Spine J 33(7):2688-2695. https://doi.org/10.1007/s00586-024-08231-8\u003c/li\u003e\n\u003cli\u003eZhu F, Bao H, Yan P, Liu S, Zhu Z, Liu Z, Qiu Y (2017) Comparison of Surgical Outcome of Adolescent Idiopathic Scoliosis and Young Adult Idiopathic Scoliosis: A Match-Pair Analysis of 160 Patients. Spine 42(19):E1133-E1139. https://doi.org/10.1097/BRS.0000000000002106\u003c/li\u003e\n\u003cli\u003eGavotto A, Risser A, Severac F, Charles YP (2023) Influence of age and severity of Lenke 5 or 6 idiopathic scoliosis on postoperative quality of life in adult patients. Orthop Traumatol Surg Res 110:103742. https://doi.org/10.1016/j.otsr.2023.103742\u003c/li\u003e\n\u003cli\u003eAhn H, Kreder H, Mahomed N, Beaton D, Wright JG (2011) Empirically derived maximal acceptable wait time for surgery to treat adolescent idiopathic scoliosis. CMAJ 183(9):E565-E570. https://doi.org/10.1503/cmaj.101511\u003c/li\u003e\n\u003cli\u003ePontes MDS, Soeira TP, Sampaio ML, Pratali RR, Pompeu Y, Herrero C (2023) The impacts of waiting for surgical correction of Adolescent Idiopathic Scoliosis and its repercussions for publicly funded health systems: systematic review. Eur Spine J 32(2):617-624. https://doi.org/10.1007/s00586-022-07424-3\u003c/li\u003e\n\u003cli\u003eBridwell KH, Shufflebarger HL, Lenke LG, Lowe TG, Betz RR, Bassett GS (2000) Parents\u0026apos; and Patients\u0026apos; Preferences and Concerns in Idiopathic Adolescent Scoliosis: A Cross-Sectional Preoperative Analysis. Spine 25(18):2392-2399. https://doi.org/10.1097/00007632-200009150-00020\u003c/li\u003e\n\u003cli\u003eRoussouly P, Labelle H, Rouissi J, Bodin A (2013) Pre- and post-operative sagittal balance in idiopathic scoliosis: a comparison over the ages of two cohorts of 132 adolescents and 52 adults. Eur Spine J 22(Suppl 2):S203-S215. https://doi.org/10.1007/s00586-012-2571-x\u003c/li\u003e\n\u003cli\u003eLonner BS, Ren Y, Bess S, Kelly MP, Kim HJ, Shufflebarger HL, Smith JT (2019) Surgery for the Adolescent Idiopathic Scoliosis Patients After Skeletal Maturity: Early Versus Late Surgery. Spine Deform 7(1):84-92. https://doi.org/10.1016/j.jspd.2018.06.010\u003c/li\u003e\n\u003cli\u003eLee CS, Park SA, Hwang CJ, Lee DH, Kim YT, Lee MY, Suk SI (2011) A novel method of screw placement for extremely small thoracic pedicles in scoliosis. Spine 36(16):E1112-E1116. https://doi.org/10.1097/BRS.0b013e3181f7507f\u003c/li\u003e\n\u003cli\u003eWong AYL, Samartzis D, Cheung PWH, Cheung JPY (2019) How Common Is Back Pain and What Biopsychosocial Factors Are Associated With Back Pain in Patients With Adolescent Idiopathic Scoliosis? Clin Orthop Relat Res 477(4):676-686. https://doi.org/10.1097/CORR.0000000000000569\u003c/li\u003e\n\u003cli\u003eTeles AR, St-Georges M, Abduljabbar F, Simoes L, Jiang F, Ouellet J (2020) Back pain in adolescents with idiopathic scoliosis: the contribution of morphological and psychological factors. Eur Spine J 29(8):1959-1971. https://doi.org/10.1007/s00586-020-06471-y\u003c/li\u003e\n\u003cli\u003eCho GJ, Park HT, Shin JH, Hur JY, Kim YT, Kim SH, Lee KW, Kim T (2010) Age at menarche in a Korean population: secular trends and influencing factors. Eur J Pediatr 169(1):89-94. https://doi.org/10.1007/s00431-009-0993-1\u003c/li\u003e\n\u003cli\u003eSeo MY, Kim SH, Juul A, Park MJ (2020) Trend of Menarcheal Age among Korean Girls. J Korean Med Sci 35(49):e406. https://doi.org/10.3346/jkms.2020.35.e406\u003c/li\u003e\n\u003cli\u003eSabatier JP, Guaydier-Souqui\u0026egrave;res G, Benmalek A, Marcelli C (1999) Evolution of lumbar bone mineral content during adolescence and adulthood: a longitudinal study in 395 healthy females 10-24 years of age and 206 premenopausal women. Osteoporos Int 9(6):476-482. https://doi.org/10.1007/s001980050275\u003c/li\u003e\n\u003cli\u003eBonjour JP, Theintz G, Buchs B, Slosman D, Rizzoli R (1991) Critical years and stages of puberty for spinal and femoral bone mass accumulation during adolescence. J Clin Endocrinol Metab 73(3):555-563. https://doi.org/10.1210/jcem-73-3-555\u003c/li\u003e\n\u003cli\u003eEun IS, Goh TS, Kim DS, Choi M, Lee JS (2023) Comparison of Korean Body Image Questionnaires in Adolescent Idiopathic Scoliosis. Asian Spine J 17(1):47-60. https://doi.org/10.31616/asj.2021.0460\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"605\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" style=\"width: 55.5863%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003cstrong\u003e.\u0026nbsp;\u003c/strong\u003eSummary of the Data regarding the Younger-14 and 14-and-Older Groups\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 21.3576%;\"\u003e\n \u003cp\u003eY-14 (n=37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 53.8843%;\"\u003eO-14 (n=131)\u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e35 (94.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e114 (87%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.117\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eHeight (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e154.89 \u0026plusmn; 6.55*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e160.93 \u0026plusmn; 7.11*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eWeight (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e44.53 \u0026plusmn; 6.07*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e50.36 \u0026plusmn; 8.83*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e18.56 \u0026plusmn; 2.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e19.41 \u0026plusmn; 2.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.103\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eEBL (mL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e809.62 \u0026plusmn; 502.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e805.5 \u0026plusmn; 595.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.974\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eOP time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e3:06:50 \u0026plusmn; 0:28:32*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e3:19:23 \u0026plusmn; 0:27:42*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.017\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eLOS (days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e12.14 \u0026plusmn; 1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e12.16 \u0026plusmn; 1.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.93\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eFusion levels\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e10.41 \u0026plusmn; 1.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e10.53 \u0026plusmn; 1.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.627\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 19.0109%;\"\u003e\n \u003cp\u003eComplication\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e1 (2.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e2 (1.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.633\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\" style=\"width: 10.4354%;\"\u003e\n \u003cp\u003eUIV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eT2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e5 (13.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e17 (13%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"6\" style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.208\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eT3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e4 (10.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e29 (22.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eT4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e22 (59.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e75 (57.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eT5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e6 (16.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e7 (5.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eT6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e1 (0.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eT8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e2 (1.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" style=\"width: 10.4354%;\"\u003e\n \u003cp\u003eLIV\u003c/p\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eT12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e1 (2.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e4 (3.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"4\" style=\"width: 6.9225%;\"\u003e\n \u003cp\u003e0.381\u003c/p\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eL1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e10 (27%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e38 (29%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eL2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e20 (54.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e52 (39.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 8.5756%;\"\u003e\n \u003cp\u003eL3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.0811%;\"\u003e\n \u003cp\u003e6 (16.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.4943%;\"\u003e\n \u003cp\u003e4 (3.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;Data represent the mean \u0026plusmn; standard deviation values.\u003c/p\u003e\n\u003cp\u003eSignificant differences are accepted for *p-values \u0026lt; 0.05.\u003c/p\u003e\n\u003cp\u003eBMI, body mass index; EBL, estimated blood loss; OP, operation; LOS, lengths of stay; UIV, uppermost instrumented vertebra; LIV, lowest instrumented vertebra.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"602\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99.8339%;\" colspan=\"4\"\u003e\u003cstrong\u003eTable\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003cstrong\u003e.\u003c/strong\u003eSummary of the Radiographic \u0026amp; Clinical Parameters of the Younger-14 and 14-and-Older Groups\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003eY-14 (n=37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003eO-14 (n=131)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eSpinal alignment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003eMean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eProximal TK (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e10.81 \u0026plusmn; 6.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e9.89 \u0026plusmn; 5.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.415\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eDistal TK (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e11.11 \u0026plusmn; 8.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e10.53 \u0026plusmn; 8.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.719\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eTL/L Lordosis (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e-0.22 \u0026plusmn; 7.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e-2.22 \u0026plusmn; 13.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.376\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eLumbar Lordosis (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e-50.59 \u0026plusmn; 10.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e-49.44 \u0026plusmn; 10.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.551\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eRSH (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e18.51 \u0026plusmn; 13.54*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e13.43 \u0026plusmn; 11.85*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.027\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eC7-CSVL (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e4.3 \u0026plusmn; 16.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e2.81 \u0026plusmn; 11.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.605\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePT (standing) (\u0026deg;) Cobb angle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e26.35 \u0026plusmn; 6.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e24.88 \u0026plusmn; 7.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.274\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePT (prone) (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e22.27 \u0026plusmn; 7.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e21.43 \u0026plusmn; 6.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.501\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePT (bending) (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e18.41 \u0026plusmn; 6.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e17.63 \u0026plusmn; 6.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.539\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eMT (standing) (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e59.65 \u0026plusmn; 8.01*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e53.29 \u0026plusmn; 6.77*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eMT (prone) (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e39.08 \u0026plusmn; 7.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e37.71 \u0026plusmn; 7.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eMT (bending) (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e27.95 \u0026plusmn; 10.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e28.77 \u0026plusmn; 9.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.655\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eTL/L (standing) (\u0026deg;)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e32.16 \u0026plusmn; 7.46*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e28.34 \u0026plusmn; 7.44*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eTL/L (prone) (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e19.70 \u0026plusmn; 5.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e19.53 \u0026plusmn; 7.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eTL/L (bending) (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e12.08 \u0026plusmn; 7.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e11.59 \u0026plusmn; 7.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.706\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eMain Curve Flexibility (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e52.88 \u0026plusmn; 16.49*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e46.35 \u0026plusmn; 15.32*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.026\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePostoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eMT imPO (\u0026deg;) Cobb angle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e9.95 \u0026plusmn; 4.384*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e12.04 \u0026plusmn; 5.121*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.025\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eMT 2YPO (\u0026deg;)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e10.64 \u0026plusmn; 4.241*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e13.1 \u0026plusmn; 5.381*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.016\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eMT FinalPO (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e10.54 \u0026plusmn; 4.273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e12.61 \u0026plusmn; 5.382\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.072\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePerioperative change\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003e△MT imPO (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e83.25 \u0026plusmn; 7.01*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e77.49 \u0026plusmn; 9.09*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003e△MT 2YPO (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e82.28 \u0026plusmn; 6.44*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e75.61 \u0026plusmn; 9.52*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003e△MT finalPO (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e81.49 \u0026plusmn; 6.49*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e75.16 \u0026plusmn; 9.5*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003eSRS22 score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePreOP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e2.90 \u0026plusmn; 0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e2.86 \u0026plusmn; 0.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.777\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePostOP-2Y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e2.20 \u0026plusmn; 0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e2.24 \u0026plusmn; 0.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.516\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003ePostOP-Final\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e2.18 \u0026plusmn; 0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e2.26 \u0026plusmn; 0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.117\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30.3987%;\"\u003e\n \u003cp\u003e△SRS22 Final\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.7442%;\"\u003e\n \u003cp\u003e0.7 \u0026plusmn; 0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26.3365%;\"\u003e\n \u003cp\u003e0.54 \u0026plusmn; 0.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.0264%;\"\u003e\n \u003cp\u003e0.251\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;Data represent the mean \u0026plusmn; standard deviation values.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSignificant differences are accepted for *p-values \u0026lt; 0.05.\u003c/p\u003e\n\u003cp\u003eTK, thoracic kyphosis; TL/L, thoracolumbar/lumbar; RSH, radiographic shoulder height; CSVL, central sacral vertical line; PT, proximal thoracic; MT, main thoracic; imPO, immediate postoperative; 2YPO, 2-year postoperative; finalPO, final postoperative; SRS-22, Scoliosis Research Society-22 questionnaire; PreOP, preoperative; PostOP, postoperative\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"621\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 99.839%;\" colspan=\"6\"\u003e\u003cstrong\u003eTable\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003cstrong\u003e.\u0026nbsp;\u003c/strong\u003eResults of the Univariate and Multivariate Regression Analysis Indicating the Factors Associated With the Correction of the Main Thoracic Curve at the Final Postoperative Follow-up\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 35.2657%;\"\u003e\n \u003cp\u003eUnivariable analysis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 40.7407%;\"\u003e\n \u003cp\u003eMultivariable analysis\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003eB (95% CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\n \u003cp\u003eB (95% CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.784 (-1.221, -0.348)\u0026nbsp;*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\n \u003cp\u003e-0.598 (-1.072, -0.124)\u0026nbsp;*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\n \u003cp\u003e0.014\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e2.682 (-1.649, 7.012)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.223\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eHeight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.261 (-0.449, -0.074)\u0026nbsp;*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\n \u003cp\u003e-0.109 (-0.337, 0.119)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\n \u003cp\u003e0.346\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eWeight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.165 (-0.328, -0.002)\u0026nbsp;*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.047\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\n \u003cp\u003e-0.051 (-0.247, 0.146)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\n \u003cp\u003e0.611\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eBMI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.129 (-0.636, 0.377)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.614\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003ePT (standing) CA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.111 (-0.085, 0.308)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.265\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003ePT (prone)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.059 (-0.271, 0.153)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.582\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003ePT (bending)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.022 (-0.187, 0.232)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.833\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eMT (standing)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.082 (-0.107, 0.271)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.391\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eMT (prone)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.162 (-0.349, 0.025)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.089\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eMT (bending)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.157 (-0.299, -0.014)\u0026nbsp;*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.031\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\n \u003cp\u003e0.007 (-0.245, 0.606)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\n \u003cp\u003e0.965\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eTL/L (standing)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.033 (-0.155, 0.220)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.732\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eTL/L (prone)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.132 (-0.330, 0.065)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.187\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eTL/L (bending)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.073 (-0.276, 0.131)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.482\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eRotation Apex (MT)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.030 (-0.269, 0.328)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.845\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eRotation Apex (TL/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.222 (-0.012, 0.457)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eRSH\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.016 (-0.099, 0.131)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.789\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eC7-CSVL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.094 (-0.015, 0.203)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.091\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eProximal TK\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.110 (-0.126, 0.346)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.358\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eDistal TK\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e-0.032 (-0.198, 0.135)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.709\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eTL/L Lordosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.005 (-0.113, 0.122)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.934\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eLumbar Lordosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.120 (-0.016, 0.255)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.084\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 23.9936%;\"\u003e\n \u003cp\u003eFlexibility\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24.6377%;\"\u003e\n \u003cp\u003e0.129 (0.040, 0.217)\u0026nbsp;*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.628%;\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30.5958%;\"\u003e\n \u003cp\u003e0.107 (-0.102, 0.315)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10.1449%;\"\u003e\n \u003cp\u003e0.314\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;Significant differences are accepted for *p-values \u0026lt; 0.05.\u003c/p\u003e\n\u003cp\u003eBMI, body mass index; PT, proximal thoracic curve; CA, Cobb angle; MT, main thoracic curve; TL/L, thoracolumbar/lumbar curve; RSH, radiographic shoulder height; CSVL, central sacral vertical line; TK, thoracic kyphosis; CI, confidence interval\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Scoliosis, Adolescent, Spinal fusion, Age factors, Treatment outcome","lastPublishedDoi":"10.21203/rs.3.rs-5343338/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5343338/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose:\u003c/strong\u003e This study aimed to investigate how age at surgery influences outcomes in teenage patients with AIS, addressing the gap in comparative analysis within the adolescent years.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e In this retrospective cohort study, patients with AIS who underwent posterior spinal fusion were divided into two groups: \u0026lt;14 years (Y-14) and ≥14 years (O-14). Inclusion criteria were Lenke Type 1A curve, Cobb angle between 45° and 80°, and minimum 2-year follow-up. Radiographic parameters, correction rates, and Scoliosis Research Society-22 (SRS-22) scores were compared. Univariable and multivariable regression analyses were performed to identify factors associated with curve correction rates.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The study included 168 patients (Y-14, n=37; O-14, n=131). The Y-14 group demonstrated significantly larger preoperative main thoracic (MT) curves (59.65° vs. 53.29°) and greater curve flexibility (52.88% vs. 46.35%) than the O-14 group. The Y-14 group achieved higher correction rates both immediately after surgery (83.25% vs. 77.49%) and at two-year follow-up (82.28% vs. 75.61%), maintaining more favorable MT curve correction over time (Final follow-up: 10.18° vs. 12.91°). The SRS-22 scores showed no significant differences between groups. In univariable analysis, age, height, weight, MT bending, and flexibility were significantly associated with MT curve correction. Multivariable analysis confirmed age as an independent predictor of correction.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003ePatients who underwent AIS surgery before the age of 14 years demonstrated superior radiographic outcomes and maintained better correction over time than those who underwent the surgery at 14 years or older, while clinical outcomes measured using the SRS-22 scores were similar between the groups.\u003c/p\u003e","manuscriptTitle":"Straightening the Facts: Early versus Late Adolescent Surgery in Idiopathic Scoliosis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-11-26 13:53:40","doi":"10.21203/rs.3.rs-5343338/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e5d5c20f-0d5f-41f7-ac7e-1dba69ddebbd","owner":[],"postedDate":"November 26th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-11-26T13:53:54+00:00","versionOfRecord":[],"versionCreatedAt":"2024-11-26 13:53:40","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5343338","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5343338","identity":"rs-5343338","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}