Spinal sagittal alignment changes following cervical manipulation and isometric neck exercise: A retrospective study

Spinal sagittal alignment changes following cervical manipulation and isometric neck exercise: A retrospective study | 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 Spinal sagittal alignment changes following cervical manipulation and isometric neck exercise: A retrospective study Min-Guk Kim, Won-young Choi, Joon-Young Bae, Yeon-Gyu Jeong, Jung-Wan Koo This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8525369/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Purpose To investigate changes in cervical, lumbar, and sacral sagittal alignment and to examine interrelationships among these parameters following an 8-week intervention combining cervical manipulation and isometric neck exercises in patients with cervical hypolordosis. Methods This retrospective observational study reviewed medical records of adult patients (20–60 years) who underwent cervical spinal alignment assessment and received a sequential intervention at a single outpatient clinic between January 2018 and December 2024. Inclusion criteria were a C1–C7 Cobb angle < 35° on lateral cervical radiographs and availability of complete pre- and post-intervention radiographic data of the cervical spine, lumbar spine, and pelvis. A total of 130 patients met the eligibility criteria. The intervention consisted of cervical manipulation performed twice weekly for 4 weeks, followed by isometric neck exercises performed twice weekly for 30 minutes per session for an additional 4 weeks. Cervical lordosis (C1–C7 Cobb angle), lumbar lordosis (L1–S1 Cobb angle), and sacral slope were measured at baseline and at 8 weeks post-intervention. Pre- to post-intervention changes were analyzed using paired t-tests, and effect sizes were calculated using Cohen’s d. Pearson correlation and multiple linear regression analyses were conducted to explore interrelationships among alignment changes, with adjustment for age and sex. Results All sagittal alignment parameters demonstrated statistically significant improvements after the intervention (all p < 0.01). Cervical lordosis increased from 28.27 ± 3.69° to 31.69 ± 3.49°, with a mean change of 3.42 ± 1.83° and a large effect size (Cohen’s d = 1.87). Lumbar lordosis increased by 1.12 ± 4.78° ( d = 0.23), and sacral slope increased by 1.15 ± 3.08° ( d = 0.37), corresponding to small and small-to-moderate effect sizes, respectively. Although the group mean cervical lordosis remained below the conventional normal range, 34 patients (26.2%) transitioned from hypolordosis to normal cervical lordosis (35°–45°). Correlation and regression analyses revealed a strong interdependence between changes in lumbar lordosis and sacral slope ( r = 0.83, p < 0.01), whereas changes in cervical lordosis were not significantly associated with changes in either parameter. Conclusion An 8-week intervention combining cervical manipulation and isometric neck exercises resulted in significant improvements in cervical, lumbar, and sacral sagittal alignment in patients with cervical hypolordosis. The greatest structural adaptation occurred at the cervical level, while lumbar lordosis and sacral slope exhibited modest but strongly coupled changes, highlighting biomechanical coupling within the lumbosacral region. These findings suggest that sagittal spinal alignment is regulated through complex regional and global interactions rather than simple segmental linkage. Cervical hypolordosis Spinal sagittal alignment Spinal manipulation Isometric neck exercise Sacral slope Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction The rapid advancement of information and communication technology has led to a substantial increase in the use of computers and smartphones [ 1 ], which has been associated with a higher prevalence of forward head posture (FHP), an abnormal alignment of the head and cervical spine [ 2 , 3 ]. FHP is typically characterized by an anterior displacement of the head relative to the vertical reference line, resulting in a decreased craniovertebral angle and altered cervical curvature. This postural deviation often involves hyperextension of the upper cervical spine combined with flexion of the lower cervical segments [ 4 ]. Beyond localized musculoskeletal symptoms such as neck pain, muscle tension, and restricted range of motion, FHP has been associated with compensatory adaptations throughout the spine. Previous studies have reported that altered cervical alignment may contribute to increased thoracic kyphosis, changes in lumbar lordosis, and pelvic tilt, ultimately leading to global postural imbalance [ 5 , 6 ]. When such imbalance occurs, the human body engages compensatory mechanisms to maintain horizontal gaze and stabilize the center of gravity [ 7 ]. In individuals with FHP, anterior displacement of the pelvis has been described as one such compensatory response and may reflect neuromuscular adaptations involving pelvo-ocular interactions that coordinate eye movements with pelvic and trunk alignment to preserve visual orientation [ 7 ]. In this context, cervical sagittal alignment should be interpreted within the framework of global sagittal alignment, including pelvic orientation [ 8 ]. Although these compensatory strategies may temporarily restore postural balance, their persistence can impose excessive biomechanical stress on spinal structures, potentially resulting in mechanical pain or neurological dysfunction [ 8 ]. Therefore, assessment and management of postural disorders should adopt an integrative perspective encompassing the cervical spine, trunk, and pelvis. The relationship between cervical alignment and lower spinal segments is complex and mediated by biomechanical interactions across spinal regions. Changes in cervical posture may influence lower spinal segments in a sequential manner [ 9 ], or the spine may function as an integrated kinetic chain in which intersegmental coordination contributes to overall sagittal balance [ 10 ]. Supporting this concept, previous studies have demonstrated that interventions targeting cervical alignment can induce favorable changes in lower spinal posture and neurophysiological function. Cervical postural correction has been shown to improve three-dimensional spinal alignment and neural excitability in individuals with lumbosacral disorders [ 9 ], while correction of head and neck posture has been associated with increased lumbar lordosis and reduced thoracic kyphosis in both younger and older adults [ 11 ]. Furthermore, degenerative lumbar deformity has been reported to be associated with reduced cervical lordosis in adults with spinal deformity, highlighting the interdependence of cervical and lower spinal alignment [ 10 ]. Given the importance of cervical alignment in maintaining global sagittal balance, various nonsurgical interventions, including therapeutic exercise and spinal manipulation, have been widely employed. Isometric neck exercise has been reported to enhance neuromuscular control and endurance of the cervical musculature without provoking pain [ 12 ]. Spinal manipulation has also been shown to improve pain and disability in individuals with nonspecific neck pain [ 13 ]. While the symptomatic benefits of nonsurgical interventions such as therapeutic exercise and spinal manipulation are well documented, it remains clinically important to determine whether these approaches also induce measurable structural changes in spinal sagittal alignment. Radiographic assessment provides an objective means of quantifying segmental and global spinal curvature and sagittal balance, thereby allowing evaluation of treatment-related structural changes. Previous studies have emphasized the clinical relevance of sagittal alignment, demonstrating associations among pelvic morphology, lumbar lordosis, pain, and functional disability [ 14 ]. Although non-radiographic methods for assessing global sagittal balance have been proposed, their reliability and validity vary across populations and measurement approaches, underscoring the continued importance of radiographic evaluation in studies of spinal alignment [ 15 ]. However, most existing research has relied on cross-sectional designs, and few studies have investigated pre to post intervention changes in sagittal alignment. In particular, evidence regarding the effects of isometric neck exercise combined with cervical manipulation on cervical hypolordosis and their potential influence on lower spinal segments remains limited. Therefore, the purpose of the present retrospective study was to quantitatively evaluate changes in cervical and lumbar sagittal alignment, as well as sacral slope, in patients with cervical hypolordosis following an 8-week intervention combining cervical manipulation and isometric neck exercise. Additionally, this study aimed to examine correlations among these parameters to explore intersegmental relationships within the sagittal alignment chain. Materials and Methods Study Design This retrospective observational study analyzed medical records of patients who underwent radiographic assessment of spinal alignment using cervical radiographs and subsequently received cervical spinal manipulation combined with isometric neck exercise as part of routine clinical care at a single outpatient clinic in Seoul, Republic of Korea, between January 1, 2018, and December 31, 2024. Radiographic images of the cervical, lumbar, and sacral spine obtained before and after an 8-week intervention period were used for analysis. All medical records and radiographic data were anonymized prior to evaluation. We hypothesized that the 8-week sequential intervention would be associated with an increase in cervical lordosis as the primary outcome and with secondary increases in lumbar lordosis and sacral slope. We further hypothesized that changes in lumbar lordosis and sacral slope would be positively correlated. This study was approved by a Public Institutional Review Board designated by the Ministry of Health and Welfare, Republic of Korea (IRB No. P01-202504-01-043), and registered in the Clinical Research Information Service (CRIS; KCT0011038). The requirement for written informed consent was waived by the Institutional Review Board due to the retrospective nature of the study and the use of anonymized medical records. Participants This retrospective cohort study included adult patients aged 20–60 years who underwent radiographic assessment of cervical spinal alignment and subsequently received cervical spinal manipulation combined with isometric neck exercise. The inclusion criteria were as follows: (1) a C1–C7 Cobb angle < 35° on lateral cervical radiographs, operationally defined as cervical hypolordosis based on commonly reported normative ranges for cervical lordosis in sagittal alignment literature [ 16 ]; and (2) availability of complete radiographic data obtained both before and after the intervention. Patients were excluded if they had a history of cervical trauma or fracture, spinal tumors, infections, ankylosing spondylitis, congenital spinal malformations, or severe degenerative changes that could interfere with accurate radiographic measurement. Additional exclusion criteria included prior cervical spine surgery, implantation of metallic devices in the cervical region, radiographs of insufficient quality for reliable analysis, missing radiographic data at either baseline or post-intervention, or a history of receiving concurrent spinal treatment at another medical institution during the study period. During the study period, medical records of 230 patients were screened for eligibility. Of these, 130 patients met the inclusion criteria and were included in the final analysis (Fig. 1 ). Interventions All interventions were performed or directly supervised by four licensed physical therapists, each with more than 8 years of clinical experience. Prior to data collection, all therapists were trained to adhere to a standardized intervention protocol, thereby minimizing inter-therapist variability. Cervical Manipulation Cervical manipulation was administered twice weekly for 4 weeks with the aim of restoring alignment of specific cervical segments contributing to hypolordosis. Prior to each treatment session, lateral cervical radiographs were reviewed to identify target segments that most prominently contributed to hypolordotic alignment or exhibited local functional impairment. During the procedure, patients were positioned in a supine posture with the cervical spine maintained as close to a neutral position as possible [ 13 ]. The therapist stabilized the patient’s head and contacted the posterolateral aspect of the zygapophyseal joint of the target segment using the index finger. Gentle ipsilateral lateral flexion and contralateral rotation were applied until slight tissue tension was perceived, forming the corrective setup. A high-velocity, low-amplitude thrust was then delivered in a superior and medial direction toward the patient’s contralateral eye to impart a corrective force to the target segment [ 13 ] (Fig. 2 ). Isometric Neck Exercise The isometric neck exercise protocol was adapted from a previous study [ 12 ] and was performed twice weekly for 4 weeks, with each session lasting approximately 30 minutes. Each session began with postural re-education using a mirror (frontal and lateral views) to facilitate recognition and maintenance of neutral alignment of the lumbar, thoracic, and cervical spine. During the initial adaptation phase (week 1), patients performed isometric exercises in a supine position with a rolled towel placed under the neck while maintaining a chin-tuck posture. From this position, participants were instructed to contract the cervical muscles isometrically for 10 seconds followed by a 15-second rest, repeated 10–15 times. In subsequent sessions, isometric exercises were performed in a seated position by applying self-resistance with the hands in the directions of flexion, extension, lateral flexion, and rotation. The contraction duration, number of repetitions, and rest intervals were identical to those used in the supine position. Exercises were initially performed using submaximal resistance and were gradually progressed to the maximum tolerable self-resistance during each session to allow for neuromuscular adaptation [ 12 ] (Fig. 3 ). Outcome Measures Demographic data, including age and sex, were extracted from medical records. Radiographic Assessment Radiographic data were obtained from the institution’s picture archiving and communication system (PACS) and analyzed before the start of the intervention and immediately after the 8-week intervention period. All radiographs were acquired in a neutral standing posture according to the institution’s standardized imaging protocol and archived using a PACS (UB-PACSZ, UBCARE, Seoul, Korea). Lateral whole-spine radiographs encompassing the cervical spine, lumbar spine, and pelvis were used for analysis. Cervical Lordosis (C1–C7 Cobb’s Angle) Cervical lordosis was measured on lateral radiographs using a C1–C7 Cobb angle, defined as the angle between a reference line passing through the midpoint of the anterior and posterior tubercles of the atlas (C1) and a tangent line drawn along the inferior endplate of C7 [ 16 ]. Cervical sagittal alignment was operationally classified as normal lordosis (35°–45°), hypolordosis ( 45°), based on commonly used radiographic reference ranges [ 16 ]. As this study focused on cervical hypolordosis, only patients with a C1–C7 Cobb angle < 35° were included in the analysis. Radiographic measurements of cervical lordosis have been shown to demonstrate good to excellent inter- and intra-rater reliability [ 17 ] (Fig. 4 A). Lumbar Lordosis (L1–S1 Cobb’s Angle) Lumbar lordosis was measured on lateral radiographs as the angle between lines parallel to the superior endplate of L1 and the superior endplate of S1 using the Cobb method [ 18 ]. Lumbar sagittal alignment was operationally classified as normal lordosis (42°–59°), hypolordosis ( 59°), based on commonly used radiographic reference ranges reported in previous studies [ 19 ]. The Cobb measurement technique has been shown to demonstrate good intra- and inter-observer reliability in the assessment of lumbar sagittal alignment [ 18 ] (Fig. 4 B). Sacral Slope Sacral slope was measured on lateral radiographs as the angle between a line parallel to the superior endplate of S1 and a horizontal reference line [ 20 ]. Sacral sagittal alignment was operationally classified as normal (35°–45°), low ( 45°) sacral slope based on commonly used radiographic reference ranges [ 20 ]. Radiographic measurements of sacral slope have been shown to demonstrate good to excellent inter- and intra-rater reliability in adult population [ 21 ] (Fig. 4 C). Statistical Analysis Statistical analyses were performed using SPSS Statistics version 18.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics are presented as means and standard deviations for continuous variables and as frequencies for categorical variables. Normality of continuous variables was assessed using the Kolmogorov–Smirnov test ( p > 0.05) and visual inspection of histograms. As all primary outcome variables approximated a normal distribution, parametric tests were applied. Pre- to post-intervention changes in cervical lordosis, lumbar lordosis, and sacral slope were analyzed using paired t-tests. To quantify the magnitude of intervention effects, Cohen’s d for paired samples was calculated as the mean change divided by the standard deviation of the change scores and interpreted as small (0.2), moderate (0.5), or large (0.8) [ 22 ]. Associations among changes in sagittal alignment parameters were examined using Pearson correlation coefficients. In addition, multiple linear regression analyses were conducted to identify predictors of change in each sagittal parameter. Changes in alignment angles were entered as dependent variables, while age, sex, and changes in other spinal parameters were included as independent variables. Multicollinearity was assessed using variance inflation factors (VIF), with values < 5 indicating acceptable levels. Regression analyses were performed using change scores to evaluate interrelationships among intervention-related alignment changes rather than to predict post-intervention alignment levels. This approach was selected because the primary aim of the study was to examine segmental coupling in response to a uniform intervention within a single-group design. Although baseline-adjusted ANCOVA models are commonly used in comparative studies, their advantages are less pronounced in single-arm studies and may introduce overadjustment when baseline values are influenced by unmeasured anatomical factors. Model diagnostics indicated acceptable statistical assumptions. To account for multiple outcome comparisons, statistical significance was set at p < 0.01(0.05/3 = 0.01), consistent with a conservative Bonferroni-based approach Results The final study sample comprised 130 participants (Table 1 ). By definition of the inclusion criteria, all participants (100%) were classified as having cervical hypolordosis (< 35°) at baseline. At 8 weeks post-intervention, 34 participants (26.2%) transitioned into the normal cervical lordosis range (35°–45°), whereas the remaining 96 participants (73.8%) remained within the hypolordotic category (Supplementary Table 1). Table 1 General Characteristics of Participants (n = 130) Characteristic Value Age (years) 39.469 ± 9.216 Gender (male/female), n 45 / 85 Following the 8-week intervention, statistically significant improvements were observed in all sagittal alignment parameters (Table 2 ). Cervical lordosis increased by a mean of 3.42° ( p < 0.01), corresponding to a large within-group effect size (Cohen’s d = 1.87). Lumbar lordosis increased by 1.12° ( p < 0.01), demonstrating a small effect size (Cohen’s d = 0.23). Sacral slope increased by 1.15° ( p < 0.01), with a small-to-moderate effect size (Cohen’s d = 0.37). Table 2 Changes in cervical and lumbar lordosis and sacral slope following an 8-week intervention Variable Baseline (°) Post-intervention (°) Mean change (°) p-value Effect size (Cohen’s d) Cervical lordosis 28.27 ± 3.69 31.69 ± 3.49 3.42 ± 1.83 < 0.01 1.87 Lumbar lordosis 43.59 ± 10.39 44.71 ± 7.49 1.12 ± 4.78 < 0.01 0.23 Sacral slope 34.39 ± 7.39 35.54 ± 5.52 1.15 ± 3.08 < 0.01 0.37 Values are presented as mean ± SD. Although the mean post-intervention cervical lordosis (31.69°±3.49°) remained below the conventional normal range (35°–45°), the magnitude of improvement, reflected by both the absolute change and the large effect size, was accompanied by a measurable shift in alignment category in a subset of participants. When effect sizes were compared across spinal regions, cervical lordosis exhibited a larger magnitude of change than lumbar lordosis and sacral slope. Correlation analysis revealed a positive association of large magnitude between changes in lumbar lordosis and changes in sacral slope ( r = 0.83, p 0.05), indicating limited direct coupling between cervical and lower spinal alignment changes. Table 3 Pearson correlations among changes in sagittal alignment parameters Variable Δ Cervical lordosis Δ Lumbar lordosis Δ Sacral slope Δ Cervical lordosis 1 NS NS Δ Lumbar lordosis NS 1 0.83* Δ Sacral slope NS 0.83* 1 *p < 0.01, NS; not significant. In the regression model predicting changes in cervical lordosis, none of the examined variables—including age, sex, change in lumbar lordosis, or change in sacral slope—were significant predictors (Table 4 ). Conversely, regression analysis for changes in lumbar lordosis identified change in sacral slope as the strongest independent predictor (β = 0.83, p < 0.01), whereas age, sex, and change in cervical lordosis were not significant contributors (Table 5 ). This model accounted for a substantial proportion of variance in lumbar lordosis change ( R ² = 0.69). Similarly, in the model predicting changes in sacral slope, change in lumbar lordosis emerged as the only significant predictor ( β = 0.83, p < 0.01), while age, sex, and change in cervical lordosis were not significant (Table 6 ). This model also demonstrated high explanatory power ( R ²=0.70). Variance inflation factors for all models were below the predefined threshold, indicating no evidence of problematic multicollinearity. Table 4 Multiple linear regression analysis for predictors of change in cervical lordosis Variable B (95% CI) S.E. β t p-value VIF Constant 2.95 (1.19–4.71) 0.90 – 3.26 < 0.01 – Age (years) −0.01 (− 0.05–0.03) 0.02 −0.03 −0.34 0.74 1.05 Sex (male = 1) 0.38 (− 0.29–1.05) 0.34 0.10 1.10 0.27 1.08 Change in sacral slope 0.13 (− 0.07–0.33) 0.10 0.22 1.37 0.17 3.15 Change in lumbar lordosis −0.05 (− 0.17–0.07) 0.06 −0.14 −0.88 0.38 3.15 Values are presented as unstandardized regression coefficients (B), standard errors (S.E.), standardized regression coefficients (β), t-values, and p-values. Age and sex were included as covariates. Changes in sacral slope and lumbar lordosis were entered simultaneously to identify factors associated with changes in cervical lordosis. Table 5 Multiple linear regression analysis for predictors of change in lumbar lordosis (R 2 = 68.8%, F = 72.38, P < .01). Variable B (95% CI) S.E. β t p-value VIF Constant 1.44 (− 1.22–4.10) 1.36 – 1.06 0.29 – Age (years) −0.01 (− 0.07–0.05) 0.03 −0.02 −0.36 0.72 1.04 Sex (male = 1) −0.63 (− 1.61–0.35) 0.50 −0.06 −1.28 0.20 1.07 Change in cervical lordosis −0.11 (− 0.36–0.14) 0.13 −0.04 −0.88 0.38 1.10 Change in sacral slope 1.29 (1.13–1.45) 0.08 0.83 16.76 < 0.01 3.20 Values are presented as unstandardized regression coefficients (B), standard errors (S.E.), standardized regression coefficients (β), t-values, and p-values. Age and sex were included as covariates. Changes in cervical lordosis and sacral slope were entered simultaneously to identify factors associated with changes in lumbar lordosis. Table 6 Multiple linear regression analysis for predictors of change in sacral slope (R 2 = 69.7%, F = 72.03, P < .01). Variable B (95% CI) S.E. β t p-value VIF Constant −0.17 (− 1.89–1.55) 0.88 – −0.19 0.85 – Age (years) 0.00 (− 0.04–0.04) 0.02 0.00 0.04 0.97 1.04 Sex (male = 1) 0.18 (− 0.45–0.81) 0.32 0.02 0.56 0.58 1.07 Change in lumbar lordosis 0.54 (0.48–0.60) 0.03 0.83 16.76 < 0.01 3.20 Change in cervical lordosis 0.11 (− 0.05–0.27) 0.08 0.07 1.37 0.17 1.10 Values are presented as unstandardized regression coefficients (B), standard errors (S.E.), standardized regression coefficients (β), t-values, and p-values. Age and sex were included as covariates. Changes in cervical lordosis and lumbar lordosis were entered simultaneously to identify factors associated with changes in sacral slope. Discussion This retrospective study investigated changes in cervical, lumbar, and sacral sagittal alignment following an 8-week intervention combining cervical manipulation with isometric neck exercises in patients with cervical hypolordosis. The primary findings indicate that all three sagittal alignment parameters—cervical lordosis, lumbar lordosis, and sacral slope—demonstrated statistically significant post-intervention improvements. These findings are consistent with previous studies indicating that therapeutic exercise and spinal manipulation can contribute to improvements in cervical alignment and overall spinal function through neuromuscular and biomechanical mechanisms [ 12 , 23 ]. Notably, the magnitude of change differed substantially across spinal regions. Cervical lordosis demonstrated a very large within-group effect size (Cohen’s d = 1.87), indicating a robust structural response to the intervention. In contrast, lumbar lordosis and sacral slope, although statistically significant, exhibited small to small-to-moderate effect sizes (Cohen’s d = 0.23 and 0.37, respectively), suggesting more modest adaptations in the lower spinal segments. This regional pattern underscores the importance of interpreting statistical significance alongside effect size when evaluating the potential clinical relevance of radiographic changes. Because established minimal clinically important differences (MCID) for radiographic sagittal alignment parameters are currently lacking, effect size estimates were used to contextualize the magnitude and potential clinical relevance of the observed changes. In this context, the large effect size observed for cervical lordosis reflects a substantial structural response that extends beyond mere statistical significance. Beyond effect size, the observed category transition provides an additional clinically interpretable indicator of structural change. Specifically, more than one-quarter of participants (26.2%) shifted from hypolordosis to the normal cervical lordosis range following the intervention. Importantly, this categorical improvement occurred despite the group mean cervical lordosis remaining below the conventional normal range, highlighting meaningful individual-level structural adaptation that may not be fully captured by group-level averages alone. In the present study, the absolute angular increase in cervical lordosis was smaller than that reported in studies incorporating cervical traction, in which improvements exceeding 13° have been documented [ 24 ]. These discrepancies may be attributable to differences in intervention modality, treatment intensity, duration, patient characteristics, and study design. Importantly, the present findings suggest that clinically meaningful structural changes may occur even with relatively modest absolute angular improvements, particularly when interindividual variability is low, as reflected by the large effect size observed for cervical lordosis. Correlation and regression analyses collectively demonstrated a strong interdependence between lumbar lordosis and sacral slope, indicating that the lumbosacral region functions as a biomechanically coupled unit rather than as independent segments. Changes in sacral slope and lumbar lordosis were closely linked, with each parameter emerging as the strongest predictor of change in the other, whereas cervical lordosis showed no significant association with either parameter. This pattern reinforces the concept that adjacent spinal segments, particularly within the lumbopelvic region, are structurally and functionally interconnected and adapt in a coordinated manner [ 24 ]. Two principal mechanisms may explain the observed alignment changes. The first is a top-down mechanism, which proposes that improvements in cervical sagittal alignment propagate sequentially to lower spinal segments, influencing thoracic, lumbar, and sacral alignment [ 9 ]. However, the absence of significant associations between changes in cervical lordosis and changes in lumbar lordosis or sacral slope in the present study suggests that this mechanism alone cannot fully account for the observed outcomes. A second mechanism involves global postural regulation through integrated neuromuscular control, wherein sagittal alignment is maintained by compensatory interactions across multiple spinal regions rather than by direct mechanical transmission along the spinal column [ 10 ]. From this perspective, the lack of consistent cervical–lumbar associations observed in the present study may reflect adaptive neuromuscular strategies that preserve overall balance despite regional alignment changes. Similar patterns have been reported previously, with limited associations observed between cervical alignment indices and lumbar or sacral parameters [ 25 ]. Several limitations should be acknowledged. Due to the retrospective design, potential confounding variables could not be fully controlled, limiting causal inference. The absence of a control group further restricts the ability to attribute observed changes solely to the intervention. Additionally, although improvements in radiographic parameters were confirmed, their direct clinical significance in terms of pain reduction, functional outcomes, or quality of life was not assessed. Moreover, it could not be determined whether the observed changes represented normalization toward each individual’s optimal sagittal alignment. In particular, pelvic incidence—an important parameter influencing the ideal relationship between lumbar lordosis and sacral slope [ 20 ] —was not evaluated because the radiographs did not include the hip joints. Finally, the single-center nature of the study may limit the generalizability of the findings. Future studies should employ prospective, controlled designs and incorporate clinical outcome measures alongside radiographic assessments to better elucidate the functional relevance of sagittal alignment changes. Inclusion of spinopelvic parameters such as pelvic incidence would further clarify whether observed postural adaptations represent true normalization or compensatory adjustments. Larger, multicenter studies may also enhance generalizability and deepen understanding of the biomechanical and neuromuscular mechanisms underlying sagittal spinal alignment. Conclusion This study demonstrated that an 8-week intervention combining cervical manipulation and isometric neck exercises resulted in significant improvements in cervical, lumbar, and sacral sagittal alignment in patients with cervical hypolordosis. The intervention produced its strongest structural effect at the cervical level, whereas changes in lumbar lordosis and sacral slope were more modest but strongly interrelated, highlighting a close biomechanical coupling within the lumbosacral region. In contrast, cervical alignment changes were not directly associated with lower spinal segments, suggesting that global sagittal alignment is regulated through complex biomechanical and neuromuscular interactions rather than simple segmental linkage. These findings underscore the importance of region-specific as well as integrated postural regulation in spinal rehabilitation. Future prospective investigations that integrate clinical outcome measures with comprehensive spinopelvic parameters may further delineate the clinical relevance and mechanistic basis of sagittal alignment changes observed following cervical-focused interventions. Statements and Declarations Acknowledgments The authors would like to acknowledge the support of the medical staff who assisted with data collection and management. Ethics approval This study was approved by a Public Institutional Review Board designated by the Ministry of Health and Welfare, Republic of Korea (IRB No. P01-202504-01-043), and registered in the Clinical Research Information Service (CRIS; KCT0011038). The study was conducted in accordance with the Declaration of Helsinki. Consent to participate The requirement for written informed consent was waived by the Institutional Review Board due to the retrospective nature of the study and the use of anonymized medical records. Consent to publish Not applicable. This study used anonymized retrospective data, and no identifying information of participants is included in the manuscript. The demonstration images presented in Fig. 2 and Fig. 3 depict a model, and written informed consent for publication was obtained. Competing interests The authors declare that they have no competing interests relevant to the content of this article. Funding No funding was received for the conduct of this study. Availability of data and materials The datasets used and/or analyzed during the current study are available from the authors upon reasonable request. References Larsson B, Søgaard K, Rosendal L (2007) Work related neck-shoulder pain: a review on magnitude, risk factors, biochemical characteristics, clinical picture, and preventive interventions. Best Pract Res Clin Rheumatol 21:447–463. https://doi.org/10.1016/j.berh.2007.02.015 Straker L, Burgess-Limerick R, Pollock C, Coleman J, Skoss R, Maslen B (2008) Children's posture and muscle activity at different computer display heights and during paper information technology use. 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J Orthop Sports Phys Ther 42:5–18. https://doi.org/10.2519/jospt.2012.3894 Normand MC, Descarreaux M, Harrison DD, Harrison DE, Perron DL, Ferrantelli JR, Janik TJ (2007) Three dimensional evaluation of posture in standing with the PosturePrint: an intra- and inter-examiner reliability study. Chiropr Osteopat 15:15. https://doi.org/10.1186/1746-1340-15-15 Cohen L, Kobayashi S, Simic M, Dennis S, Refshauge K, Pappas E (2017) Non-radiographic methods of measuring global sagittal balance: a systematic review. Scoliosis Spinal Disord 12:30. https://doi.org/10.1186/s13013-017-0135-x Martini ML, Neifert SN, Chapman EK, Mroz TE, Rasouli JJ (2021) Cervical Spine Alignment in the Sagittal Axis: A Review of the Best Validated Measures in Clinical Practice. Global Spine J 11:1307–1312. https://doi.org/10.1177/2192568220972076 Harrison DE, Harrison DD, Cailliet R, Troyanovich SJ, Janik TJ, Holland B (2000) Cobb method or Harrison posterior tangent method: which is to choose for lateral cervical. radiographic Anal Spine 25:2072–2078. https://doi.org/10.1097/00007632-200008150-00011 Polly DW Jr, Kilkelly FX, McHale KA, Asplund LM, Mulligan M, Chang AS (1996) Measurement of lumbar lordosis. Evaluation of intraobserver, interobserver, and technique variability. Spine 21:1530–1535. https://doi.org/10.1097/00007632-199607010-00008 Eddine HK, Saleh S, Hajjar J, Harati H, Nasser Z, Desoutter A, Al Ahmar E, Estephan E (2023) Evaluation of the accuracy of new modalities in the assessment and classification of lumbar lordosis: A comparison to Cobb’s angle measurement. Heliyon 9:e18952. https://doi.org/10.1016/j.heliyon.2023.e18952 Roussouly P, Gollogly S, Berthonnaud E, Dimnet J (2005) Classification of the normal variation in the sagittal alignment of the human lumbar spine and pelvis in the standing position. Spine 30:346–353. https://doi.org/10.1097/01.brs.0000152379.54463.65 Kyrölä KK, Salme J, Tuija J, Tero I, Eero K, Arja H (2018) Intra- and Interrater Reliability of Sagittal Spinopelvic Parameters on Full-Spine Radiographs in Adults With Symptomatic Spinal Disorders. Neurospine 15:175–181. https://doi.org/10.14245/ns.1836054.027 Rosnow RL, Rosenthal R, Rubin DB (2000) Contrasts and correlations in effect-size estimation. Psychol Sci 11:446–453. https://doi.org/10.1111/1467-9280.00287 Alanazi MS, Degenhardt B, Kelley-Franklin G, Cox JM, Lipke L, Reed WR (2025) Neuromuscular Response to High-Velocity, Low-Amplitude Spinal Manipulation-An Overview. Medicina 61:187. https://doi.org/10.3390/medicina61020187 Moustafa IM, Diab AA, Harrison DE (2017) The effect of normalizing the sagittal cervical configuration on dizziness, neck pain, and cervicocephalic kinesthetic sensibility: a 1-year randomized controlled study. Eur J Phys Rehabil Med 53:57–71. https://doi.org/10.23736/S1973-9087.16.04179-4 Endo K, Suzuki H, Sawaji Y, Nishimura H, Yorifuji M, Murata K, Tanaka H, Shishido T, Yamamoto K (2016) Relationship among cervical, thoracic, and lumbopelvic sagittal alignment in healthy adults. J Orthop Surg 24:92–96. https://doi.org/10.1177/230949901602400121 Additional Declarations No competing interests reported. Supplementary Files SupplementaryTable1.docx Cite Share Download PDF Status: Under Review Version 1 posted Reviewers invited by journal 08 Feb, 2026 Editor assigned by journal 13 Jan, 2026 Submission checks completed at journal 13 Jan, 2026 First submitted to journal 05 Jan, 2026 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-8525369","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":589126017,"identity":"be6b2ac5-d4c8-432e-aaf7-10ff0d45bd06","order_by":0,"name":"Min-Guk Kim","email":"","orcid":"","institution":"Catholic University of Korea","correspondingAuthor":false,"prefix":"","firstName":"Min-Guk","middleName":"","lastName":"Kim","suffix":""},{"id":589126018,"identity":"080cc00d-7b38-4c06-8f4c-9a9681a8b22f","order_by":1,"name":"Won-young Choi","email":"","orcid":"","institution":"Samsung Balance Clinic","correspondingAuthor":false,"prefix":"","firstName":"Won-young","middleName":"","lastName":"Choi","suffix":""},{"id":589126023,"identity":"40c861c9-b4b1-40b0-8a59-b797fed022d9","order_by":2,"name":"Joon-Young Bae","email":"","orcid":"","institution":"Dr.Fit CO., Ltd","correspondingAuthor":false,"prefix":"","firstName":"Joon-Young","middleName":"","lastName":"Bae","suffix":""},{"id":589126025,"identity":"009c5483-d4a7-47a2-b97a-1d952cfea3ff","order_by":3,"name":"Yeon-Gyu Jeong","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1ElEQVRIie3OsQqCQBzH8V/crK1Jkj7CiWCLD2MEutQbWNzkFLTm1iM4Nl4IugSujrk35BZE0FkPcDcG3ZfjjoP78D9Ap/vNomGbgXxvVJn4IESdfFowqBLaHLtrf9okRT3meKTw50xG2uvSyy/1uigJRrsKgc2lhMdTI6s+BAZDOJF+rOXJU5CEDlNeSqRhMTGyNBoIEVMCKbFaLK08415eElra1cSXErO5LO59tnXM5tx1tzT0DjLitqtIHCVcDoglnQE4+1o8xBYOkz/W6XS6P+0N2hpC07MlPm0AAAAASUVORK5CYII=","orcid":"","institution":"Yeoju University","correspondingAuthor":true,"prefix":"","firstName":"Yeon-Gyu","middleName":"","lastName":"Jeong","suffix":""},{"id":589126026,"identity":"638e278d-fe0b-4d4b-8f1e-b0f0ea8d724c","order_by":4,"name":"Jung-Wan Koo","email":"","orcid":"","institution":"Catholic University of Korea","correspondingAuthor":false,"prefix":"","firstName":"Jung-Wan","middleName":"","lastName":"Koo","suffix":""}],"badges":[],"createdAt":"2026-01-06 00:53:26","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8525369/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8525369/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102620903,"identity":"a35dd2b8-e731-4095-a2c5-a0c3147c494b","added_by":"auto","created_at":"2026-02-13 16:46:10","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":39106,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of patient selection from retrospective data\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8525369/v1/8b18a39927fcffba80f95eb5.png"},{"id":102620902,"identity":"af90d843-01af-4df1-9636-0070909cdcbd","added_by":"auto","created_at":"2026-02-13 16:46:10","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":376615,"visible":true,"origin":"","legend":"\u003cp\u003eCervical manipulation technique applied to hypolordotic cervical segments using a high-velocity, low-amplitude thrust in the supine position\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8525369/v1/8e5d7e3956dc09ea25d5fb23.png"},{"id":102620905,"identity":"6491dbb6-6466-4627-a375-ce490411ceaf","added_by":"auto","created_at":"2026-02-13 16:46:10","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":530327,"visible":true,"origin":"","legend":"\u003cp\u003eIsometric neck exercise protocol performed in supine and seated positions using self-resistance in multiple movement directions\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8525369/v1/39c964718eb299f5952ada7a.png"},{"id":102620901,"identity":"5992cc33-f40c-4f38-9e5d-ceeaaf0fe532","added_by":"auto","created_at":"2026-02-13 16:46:09","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":338421,"visible":true,"origin":"","legend":"\u003cp\u003eRadiographic measurement of sagittal spinal alignment parameters\u003c/p\u003e\n\u003cp\u003eA: Measurement of cervical lordosis using the C1–C7 Cobb angle\u003c/p\u003e\n\u003cp\u003eB: Measurement of lumbar lordosis using the L1–S1 Cobb angle\u003c/p\u003e\n\u003cp\u003eB: Measurement of sacral slope using the superior endplate of S1 and a horizontal reference line\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-8525369/v1/aae9aa57de2fa5ef7f554299.png"},{"id":102620908,"identity":"fe0c583e-f377-48ea-a5c9-08ae602ef001","added_by":"auto","created_at":"2026-02-13 16:46:16","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2477504,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8525369/v1/2c2d8bd8-f91e-4243-be4a-b721ba0badd5.pdf"},{"id":102620904,"identity":"d9ae0e37-5c5a-41d7-ab5c-b3e752caff16","added_by":"auto","created_at":"2026-02-13 16:46:10","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":13261,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryTable1.docx","url":"https://assets-eu.researchsquare.com/files/rs-8525369/v1/c32712bfd57bbcd753ca1c1d.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Spinal sagittal alignment changes following cervical manipulation and isometric neck exercise: A retrospective study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe rapid advancement of information and communication technology has led to a substantial increase in the use of computers and smartphones [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], which has been associated with a higher prevalence of forward head posture (FHP), an abnormal alignment of the head and cervical spine [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. FHP is typically characterized by an anterior displacement of the head relative to the vertical reference line, resulting in a decreased craniovertebral angle and altered cervical curvature. This postural deviation often involves hyperextension of the upper cervical spine combined with flexion of the lower cervical segments [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBeyond localized musculoskeletal symptoms such as neck pain, muscle tension, and restricted range of motion, FHP has been associated with compensatory adaptations throughout the spine. Previous studies have reported that altered cervical alignment may contribute to increased thoracic kyphosis, changes in lumbar lordosis, and pelvic tilt, ultimately leading to global postural imbalance [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. When such imbalance occurs, the human body engages compensatory mechanisms to maintain horizontal gaze and stabilize the center of gravity [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. In individuals with FHP, anterior displacement of the pelvis has been described as one such compensatory response and may reflect neuromuscular adaptations involving pelvo-ocular interactions that coordinate eye movements with pelvic and trunk alignment to preserve visual orientation [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. In this context, cervical sagittal alignment should be interpreted within the framework of global sagittal alignment, including pelvic orientation [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Although these compensatory strategies may temporarily restore postural balance, their persistence can impose excessive biomechanical stress on spinal structures, potentially resulting in mechanical pain or neurological dysfunction [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Therefore, assessment and management of postural disorders should adopt an integrative perspective encompassing the cervical spine, trunk, and pelvis.\u003c/p\u003e \u003cp\u003eThe relationship between cervical alignment and lower spinal segments is complex and mediated by biomechanical interactions across spinal regions. Changes in cervical posture may influence lower spinal segments in a sequential manner [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], or the spine may function as an integrated kinetic chain in which intersegmental coordination contributes to overall sagittal balance [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Supporting this concept, previous studies have demonstrated that interventions targeting cervical alignment can induce favorable changes in lower spinal posture and neurophysiological function. Cervical postural correction has been shown to improve three-dimensional spinal alignment and neural excitability in individuals with lumbosacral disorders [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], while correction of head and neck posture has been associated with increased lumbar lordosis and reduced thoracic kyphosis in both younger and older adults [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Furthermore, degenerative lumbar deformity has been reported to be associated with reduced cervical lordosis in adults with spinal deformity, highlighting the interdependence of cervical and lower spinal alignment [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eGiven the importance of cervical alignment in maintaining global sagittal balance, various nonsurgical interventions, including therapeutic exercise and spinal manipulation, have been widely employed. Isometric neck exercise has been reported to enhance neuromuscular control and endurance of the cervical musculature without provoking pain [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Spinal manipulation has also been shown to improve pain and disability in individuals with nonspecific neck pain [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. While the symptomatic benefits of nonsurgical interventions such as therapeutic exercise and spinal manipulation are well documented, it remains clinically important to determine whether these approaches also induce measurable structural changes in spinal sagittal alignment.\u003c/p\u003e \u003cp\u003eRadiographic assessment provides an objective means of quantifying segmental and global spinal curvature and sagittal balance, thereby allowing evaluation of treatment-related structural changes. Previous studies have emphasized the clinical relevance of sagittal alignment, demonstrating associations among pelvic morphology, lumbar lordosis, pain, and functional disability [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Although non-radiographic methods for assessing global sagittal balance have been proposed, their reliability and validity vary across populations and measurement approaches, underscoring the continued importance of radiographic evaluation in studies of spinal alignment [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. However, most existing research has relied on cross-sectional designs, and few studies have investigated pre to post intervention changes in sagittal alignment. In particular, evidence regarding the effects of isometric neck exercise combined with cervical manipulation on cervical hypolordosis and their potential influence on lower spinal segments remains limited. Therefore, the purpose of the present retrospective study was to quantitatively evaluate changes in cervical and lumbar sagittal alignment, as well as sacral slope, in patients with cervical hypolordosis following an 8-week intervention combining cervical manipulation and isometric neck exercise. Additionally, this study aimed to examine correlations among these parameters to explore intersegmental relationships within the sagittal alignment chain.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eStudy Design\u003c/p\u003e\n\u003cp\u003eThis retrospective observational study analyzed medical records of patients who underwent radiographic assessment of spinal alignment using cervical radiographs and subsequently received cervical spinal manipulation combined with isometric neck exercise as part of routine clinical care at a single outpatient clinic in Seoul, Republic of Korea, between January 1, 2018, and December 31, 2024. Radiographic images of the cervical, lumbar, and sacral spine obtained before and after an 8-week intervention period were used for analysis. All medical records and radiographic data were anonymized prior to evaluation. We hypothesized that the 8-week sequential intervention would be associated with an increase in cervical lordosis as the primary outcome and with secondary increases in lumbar lordosis and sacral slope. We further hypothesized that changes in lumbar lordosis and sacral slope would be positively correlated.\u003c/p\u003e\n\u003cp\u003eThis study was approved by a Public Institutional Review Board designated by the Ministry of Health and Welfare, Republic of Korea (IRB No. P01-202504-01-043), and registered in the Clinical Research Information Service (CRIS; KCT0011038). The requirement for written informed consent was waived by the Institutional Review Board due to the retrospective nature of the study and the use of anonymized medical records.\u003c/p\u003e\n\u003cp\u003eParticipants\u003c/p\u003e\n\u003cp\u003eThis retrospective cohort study included adult patients aged 20\u0026ndash;60 years who underwent radiographic assessment of cervical spinal alignment and subsequently received cervical spinal manipulation combined with isometric neck exercise.\u003c/p\u003e\n\u003cp\u003eThe inclusion criteria were as follows: (1) a C1\u0026ndash;C7 Cobb angle\u0026thinsp;\u0026lt;\u0026thinsp;35\u0026deg; on lateral cervical radiographs, operationally defined as cervical hypolordosis based on commonly reported normative ranges for cervical lordosis in sagittal alignment literature [\u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e]; and (2) availability of complete radiographic data obtained both before and after the intervention. Patients were excluded if they had a history of cervical trauma or fracture, spinal tumors, infections, ankylosing spondylitis, congenital spinal malformations, or severe degenerative changes that could interfere with accurate radiographic measurement. Additional exclusion criteria included prior cervical spine surgery, implantation of metallic devices in the cervical region, radiographs of insufficient quality for reliable analysis, missing radiographic data at either baseline or post-intervention, or a history of receiving concurrent spinal treatment at another medical institution during the study period. During the study period, medical records of 230 patients were screened for eligibility. Of these, 130 patients met the inclusion criteria and were included in the final analysis (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eInterventions\u003c/p\u003e\n\u003cp\u003eAll interventions were performed or directly supervised by four licensed physical therapists, each with more than 8 years of clinical experience. Prior to data collection, all therapists were trained to adhere to a standardized intervention protocol, thereby minimizing inter-therapist variability.\u003c/p\u003e\n\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eCervical Manipulation\u003c/h2\u003e\n \u003cp\u003eCervical manipulation was administered twice weekly for 4 weeks with the aim of restoring alignment of specific cervical segments contributing to hypolordosis. Prior to each treatment session, lateral cervical radiographs were reviewed to identify target segments that most prominently contributed to hypolordotic alignment or exhibited local functional impairment. During the procedure, patients were positioned in a supine posture with the cervical spine maintained as close to a neutral position as possible [\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e]. The therapist stabilized the patient\u0026rsquo;s head and contacted the posterolateral aspect of the zygapophyseal joint of the target segment using the index finger. Gentle ipsilateral lateral flexion and contralateral rotation were applied until slight tissue tension was perceived, forming the corrective setup. A high-velocity, low-amplitude thrust was then delivered in a superior and medial direction toward the patient\u0026rsquo;s contralateral eye to impart a corrective force to the target segment [\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e] (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eIsometric Neck Exercise\u003c/h3\u003e\n\u003cp\u003eThe isometric neck exercise protocol was adapted from a previous study [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e] and was performed twice weekly for 4 weeks, with each session lasting approximately 30 minutes. Each session began with postural re-education using a mirror (frontal and lateral views) to facilitate recognition and maintenance of neutral alignment of the lumbar, thoracic, and cervical spine. During the initial adaptation phase (week 1), patients performed isometric exercises in a supine position with a rolled towel placed under the neck while maintaining a chin-tuck posture. From this position, participants were instructed to contract the cervical muscles isometrically for 10 seconds followed by a 15-second rest, repeated 10\u0026ndash;15 times. In subsequent sessions, isometric exercises were performed in a seated position by applying self-resistance with the hands in the directions of flexion, extension, lateral flexion, and rotation. The contraction duration, number of repetitions, and rest intervals were identical to those used in the supine position. Exercises were initially performed using submaximal resistance and were gradually progressed to the maximum tolerable self-resistance during each session to allow for neuromuscular adaptation [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e] (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eOutcome Measures\u003c/p\u003e\n\u003cp\u003eDemographic data, including age and sex, were extracted from medical records.\u003c/p\u003e\n\u003ch3\u003eRadiographic Assessment\u003c/h3\u003e\n\u003cp\u003eRadiographic data were obtained from the institution\u0026rsquo;s picture archiving and communication system (PACS) and analyzed before the start of the intervention and immediately after the 8-week intervention period. All radiographs were acquired in a neutral standing posture according to the institution\u0026rsquo;s standardized imaging protocol and archived using a PACS (UB-PACSZ, UBCARE, Seoul, Korea). Lateral whole-spine radiographs encompassing the cervical spine, lumbar spine, and pelvis were used for analysis.\u003c/p\u003e\n\u003ch3\u003eCervical Lordosis (C1\u0026ndash;C7 Cobb\u0026rsquo;s Angle)\u003c/h3\u003e\n\u003cp\u003eCervical lordosis was measured on lateral radiographs using a C1\u0026ndash;C7 Cobb angle, defined as the angle between a reference line passing through the midpoint of the anterior and posterior tubercles of the atlas (C1) and a tangent line drawn along the inferior endplate of C7 [\u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e]. Cervical sagittal alignment was operationally classified as normal lordosis (35\u0026deg;\u0026ndash;45\u0026deg;), hypolordosis (\u0026lt;\u0026thinsp;35\u0026deg;), or hyperlordosis (\u0026gt;\u0026thinsp;45\u0026deg;), based on commonly used radiographic reference ranges [\u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e]. As this study focused on cervical hypolordosis, only patients with a C1\u0026ndash;C7 Cobb angle\u0026thinsp;\u0026lt;\u0026thinsp;35\u0026deg; were included in the analysis. Radiographic measurements of cervical lordosis have been shown to demonstrate good to excellent inter- and intra-rater reliability [\u003cspan class=\"CitationRef\"\u003e17\u003c/span\u003e] (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eA).\u003c/p\u003e\n\u003ch3\u003eLumbar Lordosis (L1\u0026ndash;S1 Cobb\u0026rsquo;s Angle)\u003c/h3\u003e\n\u003cp\u003eLumbar lordosis was measured on lateral radiographs as the angle between lines parallel to the superior endplate of L1 and the superior endplate of S1 using the Cobb method [\u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e]. Lumbar sagittal alignment was operationally classified as normal lordosis (42\u0026deg;\u0026ndash;59\u0026deg;), hypolordosis (\u0026lt;\u0026thinsp;42\u0026deg;), or hyperlordosis (\u0026gt;\u0026thinsp;59\u0026deg;), based on commonly used radiographic reference ranges reported in previous studies [\u003cspan class=\"CitationRef\"\u003e19\u003c/span\u003e]. The Cobb measurement technique has been shown to demonstrate good intra- and inter-observer reliability in the assessment of lumbar sagittal alignment [\u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e] (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eB).\u003c/p\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003eSacral Slope\u003c/h2\u003e\n \u003cp\u003eSacral slope was measured on lateral radiographs as the angle between a line parallel to the superior endplate of S1 and a horizontal reference line [\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e]. Sacral sagittal alignment was operationally classified as normal (35\u0026deg;\u0026ndash;45\u0026deg;), low (\u0026lt;\u0026thinsp;35\u0026deg;), or high (\u0026gt;\u0026thinsp;45\u0026deg;) sacral slope based on commonly used radiographic reference ranges [\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e]. Radiographic measurements of sacral slope have been shown to demonstrate good to excellent inter- and intra-rater reliability in adult population [\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e] (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eC).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n \u003ch2\u003eStatistical Analysis\u003c/h2\u003e\n \u003cp\u003eStatistical analyses were performed using SPSS Statistics version 18.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics are presented as means and standard deviations for continuous variables and as frequencies for categorical variables. Normality of continuous variables was assessed using the Kolmogorov\u0026ndash;Smirnov test (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05) and visual inspection of histograms. As all primary outcome variables approximated a normal distribution, parametric tests were applied.\u003c/p\u003e\n \u003cp\u003ePre- to post-intervention changes in cervical lordosis, lumbar lordosis, and sacral slope were analyzed using paired t-tests. To quantify the magnitude of intervention effects, Cohen\u0026rsquo;s \u003cem\u003ed\u003c/em\u003e for paired samples was calculated as the mean change divided by the standard deviation of the change scores and interpreted as small (0.2), moderate (0.5), or large (0.8) [\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e]. Associations among changes in sagittal alignment parameters were examined using Pearson correlation coefficients. In addition, multiple linear regression analyses were conducted to identify predictors of change in each sagittal parameter. Changes in alignment angles were entered as dependent variables, while age, sex, and changes in other spinal parameters were included as independent variables. Multicollinearity was assessed using variance inflation factors (VIF), with values\u0026thinsp;\u0026lt;\u0026thinsp;5 indicating acceptable levels.\u003c/p\u003e\n \u003cp\u003eRegression analyses were performed using change scores to evaluate interrelationships among intervention-related alignment changes rather than to predict post-intervention alignment levels. This approach was selected because the primary aim of the study was to examine segmental coupling in response to a uniform intervention within a single-group design. Although baseline-adjusted ANCOVA models are commonly used in comparative studies, their advantages are less pronounced in single-arm studies and may introduce overadjustment when baseline values are influenced by unmeasured anatomical factors. Model diagnostics indicated acceptable statistical assumptions. To account for multiple outcome comparisons, statistical significance was set at \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01(0.05/3\u0026thinsp;=\u0026thinsp;0.01), consistent with a conservative Bonferroni-based approach\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe final study sample comprised 130 participants (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). By definition of the inclusion criteria, all participants (100%) were classified as having cervical hypolordosis (\u0026lt;\u0026thinsp;35\u0026deg;) at baseline. At 8 weeks post-intervention, 34 participants (26.2%) transitioned into the normal cervical lordosis range (35\u0026deg;\u0026ndash;45\u0026deg;), whereas the remaining 96 participants (73.8%) remained within the hypolordotic category (Supplementary Table\u0026nbsp;1).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eGeneral Characteristics of Participants (n\u0026thinsp;=\u0026thinsp;130)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristic\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eValue\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39.469\u0026thinsp;\u0026plusmn;\u0026thinsp;9.216\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender (male/female), n\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45 / 85\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eFollowing the 8-week intervention, statistically significant improvements were observed in all sagittal alignment parameters (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Cervical lordosis increased by a mean of 3.42\u0026deg; (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), corresponding to a large within-group effect size (Cohen\u0026rsquo;s d\u0026thinsp;=\u0026thinsp;1.87). Lumbar lordosis increased by 1.12\u0026deg; (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), demonstrating a small effect size (Cohen\u0026rsquo;s d\u0026thinsp;=\u0026thinsp;0.23). Sacral slope increased by 1.15\u0026deg; (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), with a small-to-moderate effect size (Cohen\u0026rsquo;s \u003cem\u003ed\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.37).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eChanges in cervical and lumbar lordosis and sacral slope following an 8-week intervention\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBaseline (\u0026deg;)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-intervention (\u0026deg;)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean change (\u0026deg;)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eEffect size\u003c/p\u003e \u003cp\u003e\u003cem\u003e(Cohen\u0026rsquo;s d)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCervical lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e28.27\u0026thinsp;\u0026plusmn;\u0026thinsp;3.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e31.69\u0026thinsp;\u0026plusmn;\u0026thinsp;3.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e3.42\u0026thinsp;\u0026plusmn;\u0026thinsp;1.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.87\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLumbar lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e43.59\u0026thinsp;\u0026plusmn;\u0026thinsp;10.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e44.71\u0026thinsp;\u0026plusmn;\u0026thinsp;7.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1.12\u0026thinsp;\u0026plusmn;\u0026thinsp;4.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSacral slope\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e34.39\u0026thinsp;\u0026plusmn;\u0026thinsp;7.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e35.54\u0026thinsp;\u0026plusmn;\u0026thinsp;5.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1.15\u0026thinsp;\u0026plusmn;\u0026thinsp;3.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.37\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eValues are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAlthough the mean post-intervention cervical lordosis (31.69\u0026deg;\u0026plusmn;3.49\u0026deg;) remained below the conventional normal range (35\u0026deg;\u0026ndash;45\u0026deg;), the magnitude of improvement, reflected by both the absolute change and the large effect size, was accompanied by a measurable shift in alignment category in a subset of participants. When effect sizes were compared across spinal regions, cervical lordosis exhibited a larger magnitude of change than lumbar lordosis and sacral slope.\u003c/p\u003e \u003cp\u003eCorrelation analysis revealed a positive association of large magnitude between changes in lumbar lordosis and changes in sacral slope (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.83, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01) (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). In contrast, changes in cervical lordosis were not significantly correlated with changes in lumbar lordosis or sacral slope (all \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05), indicating limited direct coupling between cervical and lower spinal alignment changes.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePearson correlations among changes in sagittal alignment parameters\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eΔ Cervical lordosis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eΔ Lumbar lordosis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eΔ Sacral slope\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eΔ Cervical lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eΔ Lumbar lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.83*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eΔ Sacral slope\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.83*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e*p\u0026thinsp;\u0026lt;\u0026thinsp;0.01, NS; not significant.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn the regression model predicting changes in cervical lordosis, none of the examined variables\u0026mdash;including age, sex, change in lumbar lordosis, or change in sacral slope\u0026mdash;were significant predictors (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Conversely, regression analysis for changes in lumbar lordosis identified change in sacral slope as the strongest independent predictor (β\u0026thinsp;=\u0026thinsp;0.83, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), whereas age, sex, and change in cervical lordosis were not significant contributors (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). This model accounted for a substantial proportion of variance in lumbar lordosis change (\u003cem\u003eR\u003c/em\u003e\u0026sup2; = 0.69). Similarly, in the model predicting changes in sacral slope, change in lumbar lordosis emerged as the only significant predictor (\u003cem\u003eβ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.83, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), while age, sex, and change in cervical lordosis were not significant (Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). This model also demonstrated high explanatory power (\u003cem\u003eR\u003c/em\u003e\u0026sup2;=0.70). Variance inflation factors for all models were below the predefined threshold, indicating no evidence of problematic multicollinearity.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMultiple linear regression analysis for predictors of change in cervical lordosis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eB (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eS.E.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eβ\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003et\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eVIF\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConstant\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.95 (1.19\u0026ndash;4.71)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;0.01 (\u0026minus;\u0026thinsp;0.05\u0026ndash;0.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (male\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.38 (\u0026minus;\u0026thinsp;0.29\u0026ndash;1.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.08\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChange in sacral slope\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.13 (\u0026minus;\u0026thinsp;0.07\u0026ndash;0.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChange in lumbar lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;0.05 (\u0026minus;\u0026thinsp;0.17\u0026ndash;0.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eValues are presented as unstandardized regression coefficients (B), standard errors (S.E.), standardized regression coefficients (β), t-values, and p-values. Age and sex were included as covariates. Changes in sacral slope and lumbar lordosis were entered simultaneously to identify factors associated with changes in cervical lordosis.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMultiple linear regression analysis for predictors of change in lumbar lordosis (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;68.8%, F\u0026thinsp;=\u0026thinsp;72.38, P\u0026thinsp;\u0026lt;\u0026thinsp;.01).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eB (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eS.E.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eβ\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003et\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eVIF\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConstant\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.44 (\u0026minus;\u0026thinsp;1.22\u0026ndash;4.10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;0.01 (\u0026minus;\u0026thinsp;0.07\u0026ndash;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (male\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;0.63 (\u0026minus;\u0026thinsp;1.61\u0026ndash;0.35)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;1.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.07\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChange in cervical lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;0.11 (\u0026minus;\u0026thinsp;0.36\u0026ndash;0.14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChange in sacral slope\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.29 (1.13\u0026ndash;1.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e16.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eValues are presented as unstandardized regression coefficients (B), standard errors (S.E.), standardized regression coefficients (β), t-values, and p-values. Age and sex were included as covariates. Changes in cervical lordosis and sacral slope were entered simultaneously to identify factors associated with changes in lumbar lordosis.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMultiple linear regression analysis for predictors of change in sacral slope (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;69.7%, F\u0026thinsp;=\u0026thinsp;72.03, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.01).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eB (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eS.E.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eβ\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003et\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eVIF\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConstant\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;0.17 (\u0026minus;\u0026thinsp;1.89\u0026ndash;1.55)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026ndash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 (\u0026minus;\u0026thinsp;0.04\u0026ndash;0.04)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (male\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.18 (\u0026minus;\u0026thinsp;0.45\u0026ndash;0.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.07\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChange in lumbar lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.54 (0.48\u0026ndash;0.60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e16.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChange in cervical lordosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.11 (\u0026minus;\u0026thinsp;0.05\u0026ndash;0.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eValues are presented as unstandardized regression coefficients (B), standard errors (S.E.), standardized regression coefficients (β), t-values, and p-values. Age and sex were included as covariates. Changes in cervical lordosis and lumbar lordosis were entered simultaneously to identify factors associated with changes in sacral slope.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis retrospective study investigated changes in cervical, lumbar, and sacral sagittal alignment following an 8-week intervention combining cervical manipulation with isometric neck exercises in patients with cervical hypolordosis. The primary findings indicate that all three sagittal alignment parameters\u0026mdash;cervical lordosis, lumbar lordosis, and sacral slope\u0026mdash;demonstrated statistically significant post-intervention improvements. These findings are consistent with previous studies indicating that therapeutic exercise and spinal manipulation can contribute to improvements in cervical alignment and overall spinal function through neuromuscular and biomechanical mechanisms [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eNotably, the magnitude of change differed substantially across spinal regions. Cervical lordosis demonstrated a very large within-group effect size (Cohen\u0026rsquo;s \u003cem\u003ed\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.87), indicating a robust structural response to the intervention. In contrast, lumbar lordosis and sacral slope, although statistically significant, exhibited small to small-to-moderate effect sizes (Cohen\u0026rsquo;s \u003cem\u003ed\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.23 and 0.37, respectively), suggesting more modest adaptations in the lower spinal segments. This regional pattern underscores the importance of interpreting statistical significance alongside effect size when evaluating the potential clinical relevance of radiographic changes. Because established minimal clinically important differences (MCID) for radiographic sagittal alignment parameters are currently lacking, effect size estimates were used to contextualize the magnitude and potential clinical relevance of the observed changes. In this context, the large effect size observed for cervical lordosis reflects a substantial structural response that extends beyond mere statistical significance.\u003c/p\u003e \u003cp\u003eBeyond effect size, the observed category transition provides an additional clinically interpretable indicator of structural change. Specifically, more than one-quarter of participants (26.2%) shifted from hypolordosis to the normal cervical lordosis range following the intervention. Importantly, this categorical improvement occurred despite the group mean cervical lordosis remaining below the conventional normal range, highlighting meaningful individual-level structural adaptation that may not be fully captured by group-level averages alone. In the present study, the absolute angular increase in cervical lordosis was smaller than that reported in studies incorporating cervical traction, in which improvements exceeding 13\u0026deg; have been documented [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. These discrepancies may be attributable to differences in intervention modality, treatment intensity, duration, patient characteristics, and study design. Importantly, the present findings suggest that clinically meaningful structural changes may occur even with relatively modest absolute angular improvements, particularly when interindividual variability is low, as reflected by the large effect size observed for cervical lordosis.\u003c/p\u003e \u003cp\u003eCorrelation and regression analyses collectively demonstrated a strong interdependence between lumbar lordosis and sacral slope, indicating that the lumbosacral region functions as a biomechanically coupled unit rather than as independent segments. Changes in sacral slope and lumbar lordosis were closely linked, with each parameter emerging as the strongest predictor of change in the other, whereas cervical lordosis showed no significant association with either parameter. This pattern reinforces the concept that adjacent spinal segments, particularly within the lumbopelvic region, are structurally and functionally interconnected and adapt in a coordinated manner [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Two principal mechanisms may explain the observed alignment changes. The first is a top-down mechanism, which proposes that improvements in cervical sagittal alignment propagate sequentially to lower spinal segments, influencing thoracic, lumbar, and sacral alignment [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. However, the absence of significant associations between changes in cervical lordosis and changes in lumbar lordosis or sacral slope in the present study suggests that this mechanism alone cannot fully account for the observed outcomes. A second mechanism involves global postural regulation through integrated neuromuscular control, wherein sagittal alignment is maintained by compensatory interactions across multiple spinal regions rather than by direct mechanical transmission along the spinal column [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. From this perspective, the lack of consistent cervical\u0026ndash;lumbar associations observed in the present study may reflect adaptive neuromuscular strategies that preserve overall balance despite regional alignment changes. Similar patterns have been reported previously, with limited associations observed between cervical alignment indices and lumbar or sacral parameters [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSeveral limitations should be acknowledged. Due to the retrospective design, potential confounding variables could not be fully controlled, limiting causal inference. The absence of a control group further restricts the ability to attribute observed changes solely to the intervention. Additionally, although improvements in radiographic parameters were confirmed, their direct clinical significance in terms of pain reduction, functional outcomes, or quality of life was not assessed. Moreover, it could not be determined whether the observed changes represented normalization toward each individual\u0026rsquo;s optimal sagittal alignment. In particular, pelvic incidence\u0026mdash;an important parameter influencing the ideal relationship between lumbar lordosis and sacral slope [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] \u0026mdash;was not evaluated because the radiographs did not include the hip joints. Finally, the single-center nature of the study may limit the generalizability of the findings. Future studies should employ prospective, controlled designs and incorporate clinical outcome measures alongside radiographic assessments to better elucidate the functional relevance of sagittal alignment changes. Inclusion of spinopelvic parameters such as pelvic incidence would further clarify whether observed postural adaptations represent true normalization or compensatory adjustments. Larger, multicenter studies may also enhance generalizability and deepen understanding of the biomechanical and neuromuscular mechanisms underlying sagittal spinal alignment.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study demonstrated that an 8-week intervention combining cervical manipulation and isometric neck exercises resulted in significant improvements in cervical, lumbar, and sacral sagittal alignment in patients with cervical hypolordosis. The intervention produced its strongest structural effect at the cervical level, whereas changes in lumbar lordosis and sacral slope were more modest but strongly interrelated, highlighting a close biomechanical coupling within the lumbosacral region. In contrast, cervical alignment changes were not directly associated with lower spinal segments, suggesting that global sagittal alignment is regulated through complex biomechanical and neuromuscular interactions rather than simple segmental linkage. These findings underscore the importance of region-specific as well as integrated postural regulation in spinal rehabilitation. Future prospective investigations that integrate clinical outcome measures with comprehensive spinopelvic parameters may further delineate the clinical relevance and mechanistic basis of sagittal alignment changes observed following cervical-focused interventions.\u003c/p\u003e"},{"header":"Statements and Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors would like to acknowledge the support of the medical staff who assisted\u003c/p\u003e\n\u003cp\u003ewith data collection and management.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eEthics approval\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by a Public Institutional Review Board designated by the Ministry of Health and Welfare, Republic of Korea (IRB No. P01-202504-01-043), and registered in the Clinical Research Information Service (CRIS; KCT0011038).\u0026nbsp;The study was conducted in accordance with the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent to participate\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe requirement for written informed consent was waived by the Institutional Review Board due to the retrospective nature of the study and the use of anonymized medical records.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent to publish\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable. This study used anonymized retrospective data, and no identifying information of participants is included in the manuscript. The demonstration images presented in Fig. 2 and Fig. 3 depict a model, and written informed consent for publication was obtained.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCompeting interests\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests relevant to the content of this article.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eFunding\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNo funding was received for the conduct of this study.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAvailability of data and materials\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analyzed during the current study are available from the authors upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLarsson B, S\u0026oslash;gaard K, Rosendal L (2007) Work related neck-shoulder pain: a review on magnitude, risk factors, biochemical characteristics, clinical picture, and preventive interventions. 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J Orthop Surg 24:92\u0026ndash;96. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1177/230949901602400121\u003c/span\u003e\u003cspan address=\"10.1177/230949901602400121\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"european-spine-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"esjo","sideBox":"Learn more about [European Spine Journal](http://link.springer.com/journal/586)","snPcode":"586","submissionUrl":"https://submission.springernature.com/new-submission/586/3","title":"European Spine Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Cervical hypolordosis, Spinal sagittal alignment, Spinal manipulation, Isometric neck exercise, Sacral slope","lastPublishedDoi":"10.21203/rs.3.rs-8525369/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8525369/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eTo investigate changes in cervical, lumbar, and sacral sagittal alignment and to examine interrelationships among these parameters following an 8-week intervention combining cervical manipulation and isometric neck exercises in patients with cervical hypolordosis.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003e This retrospective observational study reviewed medical records of adult patients (20\u0026ndash;60 years) who underwent cervical spinal alignment assessment and received a sequential intervention at a single outpatient clinic between January 2018 and December 2024. Inclusion criteria were a C1\u0026ndash;C7 Cobb angle\u0026thinsp;\u0026lt;\u0026thinsp;35\u0026deg; on lateral cervical radiographs and availability of complete pre- and post-intervention radiographic data of the cervical spine, lumbar spine, and pelvis. A total of 130 patients met the eligibility criteria. The intervention consisted of cervical manipulation performed twice weekly for 4 weeks, followed by isometric neck exercises performed twice weekly for 30 minutes per session for an additional 4 weeks. Cervical lordosis (C1\u0026ndash;C7 Cobb angle), lumbar lordosis (L1\u0026ndash;S1 Cobb angle), and sacral slope were measured at baseline and at 8 weeks post-intervention. Pre- to post-intervention changes were analyzed using paired t-tests, and effect sizes were calculated using Cohen\u0026rsquo;s d. Pearson correlation and multiple linear regression analyses were conducted to explore interrelationships among alignment changes, with adjustment for age and sex.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eAll sagittal alignment parameters demonstrated statistically significant improvements after the intervention (all \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Cervical lordosis increased from 28.27\u0026thinsp;\u0026plusmn;\u0026thinsp;3.69\u0026deg; to 31.69\u0026thinsp;\u0026plusmn;\u0026thinsp;3.49\u0026deg;, with a mean change of 3.42\u0026thinsp;\u0026plusmn;\u0026thinsp;1.83\u0026deg; and a large effect size (Cohen\u0026rsquo;s \u003cem\u003ed\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.87). Lumbar lordosis increased by 1.12\u0026thinsp;\u0026plusmn;\u0026thinsp;4.78\u0026deg; (\u003cem\u003ed\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.23), and sacral slope increased by 1.15\u0026thinsp;\u0026plusmn;\u0026thinsp;3.08\u0026deg; (\u003cem\u003ed\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.37), corresponding to small and small-to-moderate effect sizes, respectively. Although the group mean cervical lordosis remained below the conventional normal range, 34 patients (26.2%) transitioned from hypolordosis to normal cervical lordosis (35\u0026deg;\u0026ndash;45\u0026deg;). Correlation and regression analyses revealed a strong interdependence between changes in lumbar lordosis and sacral slope (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.83, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), whereas changes in cervical lordosis were not significantly associated with changes in either parameter.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eAn 8-week intervention combining cervical manipulation and isometric neck exercises resulted in significant improvements in cervical, lumbar, and sacral sagittal alignment in patients with cervical hypolordosis. The greatest structural adaptation occurred at the cervical level, while lumbar lordosis and sacral slope exhibited modest but strongly coupled changes, highlighting biomechanical coupling within the lumbosacral region. These findings suggest that sagittal spinal alignment is regulated through complex regional and global interactions rather than simple segmental linkage.\u003c/p\u003e","manuscriptTitle":"Spinal sagittal alignment changes following cervical manipulation and isometric neck exercise: A retrospective study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-13 16:46:05","doi":"10.21203/rs.3.rs-8525369/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewersInvited","content":"","date":"2026-02-08T09:31:14+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-14T04:19:51+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-14T04:19:47+00:00","index":"","fulltext":""},{"type":"submitted","content":"European Spine Journal","date":"2026-01-06T00:48:06+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"european-spine-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"esjo","sideBox":"Learn more about [European Spine Journal](http://link.springer.com/journal/586)","snPcode":"586","submissionUrl":"https://submission.springernature.com/new-submission/586/3","title":"European Spine Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"212aa4fe-79ae-4705-bbce-200bf37698b2","owner":[],"postedDate":"February 13th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-02-13T16:46:05+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-13 16:46:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8525369","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8525369","identity":"rs-8525369","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}