The Longitudinal Variations of Paraspinal Muscle Fatty Infiltration in Obese Patients after Bariatric Surgery

The Longitudinal Variations of Paraspinal Muscle Fatty Infiltration in Obese Patients after Bariatric Surgery | 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 The Longitudinal Variations of Paraspinal Muscle Fatty Infiltration in Obese Patients after Bariatric Surgery Yuxue Xie, Chongwen Zhan, Hongyue Tao, Qing Li, Rong Hua, Qiyuan Yao, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6303104/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 11 Jun, 2025 Read the published version in European Spine Journal → Version 1 posted 13 You are reading this latest preprint version Abstract Purpose: The effect of bariatric surgery on the bone density reduction is well documented, while its effect on the paraspinal muscle remains unclear. The purpose of this study is to analyze changes in muscle fatty infiltration one year after bariatric surgery in young obese adults. Methods: Fifty-two obese patients (38 female, BMI = 43.5± 5.6 kg/m 2 ) who underwent Bariatric surgery and 52 age- and sex-matched controls with normal weight (BMI = 23.5±5.6 kg/m 2 ) at baseline. Forty patients came back at one-year follow-up. Quantitative Dixon and T2 mapping MRI were employed to evaluate the paraspinal muscles and intervertebral disc degeneration respectively. Fat fraction (FF) and cross-sectional area (CSA) of multifidus muscle (MF), erector spinae (ES), and psoas muscles and T2 value of intervertebral disc at various disc levels were taken and compared between patients and controls, as well as preoperatively and postoperatively for the patients. Furthermore, the correlations of these MRI variables from preoperative to the postoperative and clinical variables were explored. Pearson correlation was used to analysis the link between the variables of muscle MRI parameters and weight as well as obesity-related experimental indices from preoperative to the postoperative. Results: Obese patients exhibited increased FF values in three muscles, increased CSA in the ES at all disc levels ( P <0.001). While for the MF and psoas, only L4/5 and L5/S1 disc levels demonstrated significant increased CSA value in patient group ( P <0.05). Patient group displayed significantly lower T2 values and higher Pfirrmann classification of all the five intervertebral discs (all P < 0.05), particularly in high levels. One year postoperatively, FF values of the ES and MF significantly decreased only at L1/2-disc level ( P 0.05). While a link between variables of high-sensitivity C-reactive protein and FF decrease of the ES and MF from preoperative to postoperative were evidenced ( P < 0.05). Conclusions Significant improvements in muscle fatty infiltration were observed postoperatively in the ES and MF at higher level, which may be linked to the improvements of high-sensitivity C-reactive protein. Q-Dixon Longitudinal fatty infiltration Paraspinal muscle Bariatric surgery Figures Figure 1 Figure 2 Figure 3 Introduction Morbid obesity and its associated comorbidities are major global public health issues, leading to serious physical and musculoskeletal disorders [1–4]. Bariatric surgery, in conjunction with nutritional education and close follow-up, has been widely accepted as the most effective treatment for weight reduction and related issues[5, 6]. Unfortunately, bariatric surgery is also associated with complications. The best acknowledged one complication is that bariatric surgery adversely affects skeletal health, particular for the spine [7–14]. While compared to the deeply insight of detrimental impact on vertebrae health, the effect of bariatric surgery on paraspinal muscle condition remains unclear for obese patients[15]. Study has shown that rapid and substantial weight loss can lead to significant losses in lean mass after Bariatric surgery [16]. Understanding this longitudinal relationship is important in developing an effective approach for exercise guiding after surgery the in obese patients after bariatric surgery[17]. Decline in paraspinal muscle health has been characterized by increased intramuscular fat and decreased size (muscle atrophy)[18]. Various quantitative MRI methods have been developed to objectively assess the degree of muscle fatty infiltration. Recently, the Q-Dixon method has gained popularity for its application in musculoskeletal MRI, particularly for calculating muscle fat fraction (FF) value of the muscles. This accurate and noninvasive imaging tool, combined with bariatric surgery’s capacity for rapid weight loss, offers a unique opportunity to evaluate the muscle change pattern based on longitudinal design. Since strong correlations have been demonstrated between age and muscle fatty infiltration have been established across different anatomic regions[19, 20], the present study included young adults to explore weight-related paraspinal muscle fatty infiltration. The purpose of this longitudinal study was to quantitatively examine weight-related variation in the compositional and morphological parameters of different paraspinal muscles using the Q-Dixon sequence in obese patients and to investigate the change pattern in these parameters one year after bariatric surgery. Methods Participants This prospective cohort study was approved by the Institutional Review Board in our hospital, and informed consent was obtained from all participants. Consecutive patients with obesity (BMI ≥ 30kg/m 2 ) admitted to the Department of General Surgery Center for bariatric surgery between November 2022 and May 2023 were invited to participate. The bariatric procedures were conducted under the supervision of a single senior bariatric surgeon. Healthy controls were recruited through the health management center of our hospital. Inclusion criteria were age 20–50 years to exclude the age-related variations; stated willingness and ability to participate and follow the research protocol. Exclusion criteria included conventional lumbar MRI findings of qualitative anatomic variations, spinal lesions, lumbar spondylolisthesis, vertebral fractures, and end-plate osteochondritis; a history of spine surgery or trauma; ankylosing spondylitis, rheumatologic disorders, and muscular dystrophy; severe infections or dysfunctions (heart, lung, liver, and kidney) that pose a high risk to trial safety or individuals with life-threatening diseases or serious unstable underlying conditions; contraindications for MR examination; a history of systematic paravertebral muscle function exercises within the past 6 months; and incomplete MRI data. Age and gender were matched between the obese and control group. The final sample included 104 participants (52 in each group). A total of 30 patients (57.7%) finished all the postoperative clinical and MRI examinations at one-year follow-up visits (Figure. 1). Surgical Techniques Standardized bariatric surgery was performed[21]. After pneumoperitoneum was established, a 12 mm puncture was inserted into the umbilicus, and a 5 mm puncture was inserted under the xiphoid process, in the right upper quadrant, and in the left upper quadrant. The greater curvature of the stomach is mobilized, extending from the anterior pyloric vein to the complete fundus of the stomach. Medtronic Tri-Staple intelligent cutting and closing device (purple staple cartridge: EGIA6OAMT) was used to cut and anastomose 3cm away from the pylorus. Care was taken to keep the staple line 1cm away from the His angle to prevent ischemia and obstruction at the gastroesophageal junction while fully resecting the fundus of the stomach. After the cut is completed, a Johnson & Johnson 3 − 0 barbed suture (SXMD1B405) was used for full-thickness reinforcement, securing the incision edge to minimize bleeding. The patients were then extubated and transferred back to the ward. Clinical and Experimental Variables for Obese Group Preoperative and postoperative clinical variables were collected and recorded by a single surgeon, including age, sex, body mass index (BMI), waist circumference, hip circumference, waist-to-hip ratio, and total weight loss (TWL) percentage. The TWL was calculated as (pre-operative weight-follow-up weight) / pre-operative weight*100 [22]. Obesity-related experimental indices, including glycated hemoglobin, fasting blood glucose, cholesterol, high-density lipoprotein, low-density lipoprotein cholesterol, triglycerides, and high-sensitivity C-reactive protein (hs-CRP) were measured using an analyzer (Cobas 8000 c702, Roche Diagnostics, Basel, Switzerland). Glycated hemoglobin was determined by high-performance liquid chromatography (HPLC; ADAM A1c HA-8180 V, ARKRAY, Inc., Kyoto, Japan). MR acquisition Lumbar MR examinations were performed using a 3.0-T MRI system (MAGNETOM Prisma, Siemens Healthineer) with a 32-channel spine matrix coil in the supine position. Scan range needed to cover the entire lumbar vertebrae (L1-S1). The imaging protocol included a sagittal T1-weighted (T1W) Turbo Spin Echo (TSE) sequence, sagittal T2W TSE sequence, axial T2W TSE sequence, axial three-dimensional T2*-corrected 6-echo Dixon volume-interpolated breath-hold examination sequence, and sagittal T2 mapping sequences. FF map and T2 map reconstruction were automatically completed. Detailed parameters of each sequence are summarized in Table 1 . Table 1 MRI sequences and parameters. Sag T2W Sag T1W Axi T2W Axi Q-Dixon Sag T2 mapping TR 2400 460 2400 10.3 2000 TE 89 8.6 94 1.04, 2.5, 3.96, 5.42, 6.88, 8.34 10.5, 21, 31.5, 42, 52.5, 63 No. of slices per slab 11 11 15 64 14 slice thickness, mm 4 4 4 3 3 Space between slices 4.8 4.8 4.4 / 3.6 Field of view, mm2 280 280 380 300 250 Phase encoding direction H > > F H > > F A > > P A > > P A > > P averages 1 1 1 1 1 Flip angle, degrees 120 120 160 4 180 Bandwidth, Hz/Px 252 252 250 900 202 Acquisition time, minutes: seconds 00:56 00:58 00:57 00:18 02:14 Echo train length 20 3 23 6 6 Matrix 320*320 640*640 640*640 192*180 276*384 Sag, sagittal; T2W, T2-weighted; T1W, T1-weighted; Axi, axial; TR, repetition time; TE, echo time MRI image analysis Dixon images were imported into the post-processing workstation (Syngo software version B17, Siemens Healthineers) for data extraction. Regions of interest (ROIs) were placed at the contours of the MF, ES, and psoas muscles manually for each axial slice from the middle-most level of the L1/2 to L5/S1 disc levels on the FF maps (Figure. 2)[23]. Left and right cross-sectional area (CSA) and FF values were recorded and averaged, respectively. The functional CSA (FCSA) was calculated using the formula: FCSA = CSA × (1-FF%). Intervertebral disc degeneration (IVDD) was evaluated from L1-L2 to L5-S1 disc levels using the Pfirrmann grading system on T2W images[24] and quantified on T2mapping images to calculate T2 value. All ROIs for all participants were independently and blindly segmented by two radiologists (with 12 and 7 years of experience in skeletal muscle radiology, respectively) to calculate inter-observer and intra-observer agreement. Statistical analysis Data analysis was performed using R Language (R version 3.5.1; http://www.r-project.org/ ). Categorical variables were compared using Chi-square or Fisher’s exact test. Non-parametric continuous variables were compared using Mann-Whitney U test or Kruskal-Wallis test according to how many variables were compared at a time. The Parameters of the study samples were presented as mean (±) standard deviation for continuous variables and absolute counts. An alpha value of P < 0.05 was accepted as statistically significant. Pearson correlation tests were conducted to explore the relationship between the variations of muscle FF and clinical parameters from preoperative to postoperative data. Correlations were classified as follows: Pearson correlation coefficient (PCC) > 0.6, extremely strong; 0.6–0.4, moderate; < 0.4 weak, and no correlation. The Friedman M test was used to compare muscle FF among different lumbar disc levels. The intraclass correlation coefficients (ICCs) of FF and CSA were calculated using a two-way mixed absolute agreement model. The ICCs were graded as follows: excellent reliability, 0.75 ≤ ICC ≤ 1; fair to good, 0.4 ≤ ICC < 0.75; and poor, 0 ≤ ICC < 0.4). Results The ICCs results were excellent, indicating minimal interobserver variability, and the means of both measurements were used for further analysis. Fifty-two obese patients (45 women, mean age 33.15 ± 6.51 years old) and 52 controls (45 women, mean age 33.52 ± 3.43 years old) with normal weight were included after matching for age and gender. Obese patients and control groups were similar in height ( P = 0.73), while the obese group was much heavier than the control group (37.66 ± 5.05 vs. 24.05 ± 3.00 kg/m 2 , P < 0.001). Finally, 30 patients returned for MRI and clinical analysis at one-year follow-up. Table 2 details the sociodemographic and clinical characteristics at baseline and one year postoperatively for patients with complete follow-up. Mean BMI showed significant decreases from preoperative to postoperative data (38.21 ± 4.74 vs. 26.27 ± 3.20 kg/m 2 , P < 0.001). The postoperative EWL was 99.5 ± 24.7%. The postoperative TWL was 30.8 ± 6.9%. Table 2 General and biochemical indicators comparisons between preoperative and postoperative measurements. Preoperative Postoperative P value Weight (kg) 109.1 ± 20.8 74.1 ± 13.1 < 0.001 BMI (kg/m2) 38.2 ± 4.7 24.3 ± 3.7 < 0.001 Waist circumference (cm) 116.9 ± 12.0 88.1 ± 8.2 < 0.001 Hip circumference (cm) 119.2 ± 9.9 94.3 ± 7.1 < 0.001 Waist-to-hip ratio 0.98 ± 0.06 0.79 ± 0.12 < 0.001 Glycated hemoglobin (%) 6.1 ± 0.8 5.2 ± 0.1 < 0.001 Fasting blood glucose (mmol/L) 5.9 ± 1.0 4.3 ± 0.4 < 0.001 Cholesterol (mmol/L) 4.9 ± 0.8 4.2 ± 0.8 0.02 LDL-C(mmol/L) 3.2 ± 0.7 2.2 ± 0.6 0.01 HDL-C(mmol/L) 1.1 ± 0.2 1.2 ± 0.4 < 0.001 Triglyceride (mmol/L) 1.9 ± 1.3 0.7 ± 0.4 < 0.001 Hs-CRP (mg/L) 4.7 ± 2.9 1.1 ± 1.3 < 0.001 Data were reported as mean ± standard deviations for continuous variables. P < 0.05 was reported as Bold. BMI, body mass index; WBC, white blood cell; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; Hs-CRP, high-sensitivity C-creative protein. Bolded P value indicates a significant difference between groups. Muscle Parameters Comparisons between Patients and Controls Muscle parameters for FF, CSA, and FCSA were calculated and compared between the control group and obese group at baseline (Tables 3 ). When compared at the same disc level and muscle specifically, obese patients had significantly higher mean FF for all three paraspinal muscles at all disc levels (all P < 0.001, Table 3 ). However, CSA showed different weight-related variation in different muscles at different levels. For the ES, obese patients demonstrated significant higher CSA than controls at all levels ( P 0.05, Table 3 ). These differences were more pronounced at L4/5 and L5-S1 disc levels ( P < 0.05, Table 3 ). Table 3 Muscle compositional and morphological parameters comparisons between obese group and control group. ES MF Psoas Control group Obese group P value Control group Obese group P value Control group Obese group P value FF (%) L1/2 5.4 ± 2.8 7.7 ± 2.8 < 0.001 8.9 ± 4.9 11.7 ± 4.3 0.002 L2/3 5.4 ± 2.5 7.6 ± 2.7 < 0.001 7.3 ± 3.5 10.2 ± 3.4 < 0.001 6.1 ± 2.3 7.3 ± 3.7 0.06 L3/4 5.9 ± 2.6 8.2 ± 2.7 < 0.001 7.5 ± 3.5 10.2 ± 2.9 < 0.001 5.5 ± 2.1 6.6 ± 3.1 0.03 L4/5 7.0 ± 2.9 8.6 ± 2.7 0.004 8.4 ± 4.1 10.0 ± 4.1 0.045 5.3 ± 2.0 6.3 ± 3.4 0.05 L5/S1 10.0 ± 3.8 13.0 ± 3.9 < 0.001 7.7 ± 4.1 10.9 ± 3.7 < 0.001 4.8 ± 1.8 6.6 ± 3.6 < 0.001 CSA (cm2) L1/2 11.7 ± 5.0 16.3 ± 4.8 < 0.001 1.9 ± 0.7 2.1 ± 0.9 0.175 L2/3 12.1 ± 4.8 16.9 ± 4.9 < 0.001 3.3 ± 2.0 3.6 ± 2.2 0.483 4.2 ± 1.8 4.4 ± 1.8 0.53 L3/4 10.6 ± 3.7 14.3 ± 4.2 < 0.001 5.5 ± 3.2 6.0 ± 3.4 0.416 6.7 ± 2.3 7.6 ± 2.9 0.08 L4/5 9.0 ± 3.2 11.9 ± 3.1 < 0.001 6.1 ± 2.0 7.4 ± 2.5 0.006 8.7 ± 2.5 10.1 ± 3.0 0.009 L5/S1 6.8 ± 1.6 9.7 ± 3.0 < 0.001 6.3 ± 1.8 8.3 ± 2.7 < 0.001 9.4 ± 2.5 10.8 ± 2.9 0.009 FCSA (cm2) L1/2 11.1 ± 4.9 15.0 ± 4.5 < 0.001 1.8 ± 0.7 1.9 ± 0.8 0.375 L2/3 11.5 ± 4.7 15.6 ± 4.6 < 0.001 3.0 ± 1.9 3.2 ± 2.0 0.679 4.0 ± 1.7 4.1 ± 1.7 0.62 L3/4 10.0 ± 3.6 13.1 ± 3.9 < 0.001 5.1 ± 3.0 5.4 ± 3.1 0.607 6.3 ± 2.2 7.1 ± 2.7 0.11 L4/5 8.4 ± 3.1 10.9 ± 2.9 < 0.001 5.7 ± 1.9 6.6 ± 2.2 0.02 8.2 ± 2.4 9.4 ± 2.8 0.02 L5/S1 6.1 ± 1.5 8.4 ± 2.7 < 0.001 5.8 ± 1.8 7.4 ± 2.4 < 0.001 9.0 ± 2.4 10.1 ± 2.9 0.02 FF, fat fraction; CSA, cross-sectional area; FCSA, functional CSA; ES, erector spinae; MF, multifidus muscle. Bolded P value indicates a significant difference between groups ( P < 0.05). Lumbar IVVD Comparisons between Patients and Controls The intervertebral disc parameters were compared in Table 4 . Severe IVDD was more common in obese patients than that in the control group (based on both Pfirrmann classification and T2 values ( P < 0.05 for all the disc level, Table 4 ). Moreover, when comparing the groups level by level, these differences were more predominantly at upper levels ( P < 0.001, Table 4 ). Table 4 Pfirrmann classification and quantitative intervertebral disc degeneration comparisons between obese group and control group. Control group Obese group P values T2 values L1/2 104.2 ± 20.1 85.2 ± 16.8 < 0.001 L2/3 102.4 ± 20.4 89.3 ± 17.0 < 0.001 L3/4 97.5 ± 24.5 86.5 ± 23.1 0.02 L4/5 80.5 ± 28.6 68.2 ± 20.0 0.01 L5/S1 70.3 ± 25.1 56.1 ± 20.8 0.002 Pfirrmann L1/2 1.4 ± 0.7 2.4 ± 0.8 < 0.001 L2/3 1.8 ± 0.7 2.4 ± 0.9 < 0.001 L3/4 2.1 ± 1.0 2.5 ± 1.0 0.03 L4/5 2.8 ± 1.4 3.7 ± 1.2 < 0.001 L5/S1 2.8 ± 1.6 4.1 ± 1.2 < 0.001 Bolded P value indicates a significant difference between groups. Muscle and IVDD Measurements Change Pattern One Year Follow Bariatric Surgery Table 5 and Fig. 3 showed the variations of FF, CSA, and FCSA at one year after the bariatric surgery for the three muscles. Specifically, FF of ES and MF showed significant improvements at the L1/2-disc level ( P 0.05). The psoas didn’t report any reduction in FF values at any disc levels. For the CSA, the three muscles displayed different pattern after weight loss: the ES CSA showed significant reductions at all disc levels, while the MF and psoas showed on reduction except at the L4/5 and L5/S1 disc levels. Table 5 Change pattern of muscle compositional and morphological parameters one year after Bariatric surgery. ES MF Psoas Preoperative Postoperative P value Preoperative Postoperative P value Preoperative Postoperative P value FF L1/2 8.0 ± 3.4 5.3 ± 2.4 0.001 12.3 ± 4.5 10.0 ± 4.2 0.049 L2/3 7.4 ± 2.7 6.1 ± 2.3 0.10 10.1 ± 3.0 9.9 ± 2.4 0.51 5.8 ± 2.1 5.8 ± 1.6 0.90 L3/4 7.9 ± 2.8 6.4 ± 2.9 0.15 9.6 ± 2.8 8.9 ± 2.6 0.33 5.8 ± 2.2 5.5 ± 1.8 0.47 L4/5 8.7 ± 2.9 7.7 ± 2.2 0.13 10.3 ± 4.7 9.8 ± 3.4 0.54 5.2 ± 2.3 4.9 ± 1.9 0.53 L5/S1 13.6 ± 5.1 11.6 ± 4.3 0.08 10.8 ± 4.5 10.5 ± 4.7 0.66 5.5 ± 2.1 5.0 ± 2.1 0.33 CSA L1/2 19.2 ± 5.2 13.5 ± 5.2 < 0.001 2.5 ± 0.8 2.6 ± 0.8 0.5 L2/3 18.9 ± 5.4 14.0 ± 4.4 < 0.001 4.0 ± 1.8 3.5 ± 2.1 0.39 5.5 ± 1.9 5.5 ± 1.2 0.98 L3/4 15.7 ± 4.4 11.9 ± 4.2 0.002 6.0 ± 2.3 5.9 ± 2.3 0.85 8.6 ± 3.2 7.6 ± 3.2 0.33 L4/5 12.3 ± 3.5 9.4 ± 3.0 < 0.001 8.8 ± 2.2 7.2 ± 2.1 0.003 11.0 ± 3.3 9.2 ± 2.1 0.04 L5/S1 10.0 ± 3.0 7.7 ± 2.1 0.001 9.2 ± 2.6 7.0 ± 2.2 0.002 11.1 ± 3.2 9.2 ± 2.1 0.01 FCSA L1/2 17.6 ± 4.9 13.4 ± 4.3 < 0.001 2.2 ± 0.7 2.3 ± 0.9 0.37 L2/3 17.6 ± 5.1 13.5 ± 4.2 0.001 3.5 ± 1.6 3.1 ± 1.2 0.42 5.2 ± 1.8 5.2 ± 1.2 0.97 L3/4 14.5 ± 4.3 11.1 ± 4.1 0.004 5.5 ± 2.1 5.2 ± 2.6 0.91 8.1 ± 3.0 7.2 ± 3.1 0.29 L4/5 11.3 ± 3.3 8.7 ± 2.4 0.001 7.9 ± 2.0 6.2 ± 1.1 0.004 10.4 ± 3.1 8.4 ± 2.6 0.03 L5/S1 8.7 ± 2.8 6.9 ± 2.2 0.006 8.2 ± 2.3 6.2 ± 1.3 0.002 10.5 ± 3.0 8.4 ± 2.1 0.01 FF, fat fraction; CSA, cross-sectional area; FCSA, functional CSA; ES, erector spinae; MF, multifidus muscle. P value 0.05, Table S1). Correlations of the Variations between Muscle fatty infiltration and Clinical Variables With weight loss one year after surgery, the FF variations of ES and MF at the L1/2-disc level didn’t show any correlations with the variations of weight (all P > 0.05). While the FF variations showed significant correlations with the variations of the hs-CRP (PCC = -0.35, P = 0.02). Other obesity-related laboratory indices did not show any correlations with the variations of muscle fatty infiltration (all P > 0.05). Discussion In this study, we evaluated weight-related alterations in the compositional and morphological parameters of back extensor muscles and IVDD by comparing with non-obese controls in cross-sectional design as well as comparing between preoperative and postoperative data in longitudinal design using quantitative MRI in young obese adults. Our findings demonstrated heterogenous weight-related changes in muscle fat infiltration and size, which are crucial for understanding the paraspinal muscle health in obese patients. Moreover, the relationships between MF and ES muscle fatty infiltration variations at upper level and the experimental parameters surpassed that muscle composition can be affected by the inflammatory variables in obese patients. These links inspire that further research may need lay more emphasis to investigate the role of inflammatory and metabolic variables in muscle health among patients with morbid obesity. It has been widely acknowledged that paraspinal muscle fatty infiltration, and IVDD are significantly associated with obesity[25, 26]. Numerous studies have reported that obesity can be associated with muscle fatty infiltration. Study by Pinzhen Chen et al[27] indicated that people different age and gender demonstrated muscle fatty infiltration to various extents based on Dixon imaging. These pieces of information may prove valuable value of Dixon in guiding experiments aimed at mitigating muscle fatty infiltration. Our results align with the broader finding that regional changes in muscle fatty infiltration occur concurrently with obesity and manifest differently depending on anatomical location. Along with higher FF value (correspond to weaker function) is larger CSA (stronger function) of the paraspinal muscles for patients with obesity, which are contradictory for paraspinal muscle function. Therefore, we introduced the FCSA, representative as lean muscle CSA and calculated as CSA*(1-FF), to serve as a more proper parameter to characterize the muscle function[27]. As a result, FCSA was significantly higher in obese patient than in controls, indicating superior muscle function in the obese cohort. This novel finding led us to suspect a similarity to bone adaptations observed in obesity-related studies, where obese patients exhibit higher bone density due to mechanical loading[28, 29]. Therefore, our results on obesity-related muscle parameters complement existing knowledge on spinal health variations in obese patients. Higher fatty infiltration and muscle size, as well as severer IVDD, are relatively acceptable in individuals with obesity. While these findings are somewhat expected, many obese patients are curious about whether muscle fatty infiltration and IVDD can be reversed following remarkable weight-loss. This is a crucial consideration when guiding postoperative exercise regimens. However, the literature on the extent and significance of these changes in obese patients remains inconclusive. To our knowledge, this study is the first one to report the pattern of muscle variations following remarkable weight-loss one year after bariatric surgery. Our primary findings indicated that longitudinal variations of paraspinal muscles is influenced by disc level and muscle type. We found that obese participants experienced significant improvement in muscle fatty infiltration in MF and ES only at the L1/2-disc level, while the psoas did not show any significant improvements. With weight loss, relief from weight-bearing should theoretically be more pronounced from upper to lower levels. However, our results are intriguing as they show that improvement of fatty infiltration occurred only at the upper levels for MF and ES, but not at the lower levels. This suggests that improvements in muscle fatty infiltration following bariatric surgery may not solely be attributed to the relief from weight-bearing. Throughout the document, commonly suspected factors include not only mechanical unloading and also the roles of hormones, the inflammatory, and metabolic variables[30]. Among these factors associated with muscle health, substantial studies have recommended chronic inflammation as an activator of several molecular pathways involved in skeletal muscle wasting, leading to an imbalance between protein synthesis and catabolism[31, 32]. Our further correlation analysis between obesity-related laboratory indices and muscle fatty infiltration supports these findings. Specifically, improvements in hs-CRP, showed significantly moderate correlations with decrease of FF value in ES and MF at the L1/2-disc level. Consistent with our results, several previous studies have documented relationships between hs-CRP and muscle health[33, 34]. Although the potential underlying mechanisms of this association remain uncertain, the preliminary results inspire that greater attention need to be laid on the inflammatory markers in patients with morbid obesity based on our non-invasive Dixon method and longitudinal design. We also observed disparities in weight-related muscle atrophy. Interestingly, our study suggests that ES muscle size is more susceptible to weight-related mass decrease than MF. The underlying reason may be due to the significantly smaller proportion of type I muscle fibers in lumbar ES compared to MF[35]. Muscle fiber type characteristics are crucial determinants of muscle function and metabolic capacity. The MF, severing as a local stabilizer, contains higher proportion of slow type I fibers compared to ES, which functions as a global mobilizer based on mechanical properties and morphological features [36]. Specifically, the MF contains a higher proportion of slow, fatigue-resistant type I fibers, which are essential for sustained activity necessary to stabilize the [36]. On the contrary, the ES contains higher proportions of fast-contracting fibers to counterbalance forces acting on the body, making it more susceptible to weight-bearing. These findings concerning muscle fatty infiltration change patterns and their associations with inflammatory markers should be taken into consideration when guiding the most appropriate nutrition and spine-related exercise for obese patients after surgery. Conclusions One year after bariatric surgery, notable alterations in muscle fatty infiltration were observed in the ES and MF at higher level, which may be linked to hs-CPR. Additionally, longitudinal non-invasive data based on Q-Dixon could serve as an effective quantitative marker to investigate changes in paraspinal muscle function in obese patients. Limitations Several limitations in this study need to be acknowledged. Firstly, the follow-up period was only one year, which is relatively short. Secondly, the sample size was relatively small, so we cannot explore the relationship between the muscle quality and the experimental parameters. Future studies with longer follow-up periods and larger sample size could potentially enhance our results to analyze and understand the pathophysiology underlying these observations. Secondly, we didn’t include a control group undergoing non-surgical weight loss, such as lifestyle-intensive medical management. Since our purpose was not to explore the surgery-related muscle or IVDD change pattern, this comparison was not explored. Thirdly, we didn’t explore the muscle strength due to the absence of evidence suggesting muscle function frailty in our daily clinical practice, given that the patients are young adults with massive muscle mass. Lastly, we didn’t obtain muscle histological tissue to establish a definitive reference point, citing ethical constraints. Further research involving histological data on muscle is necessary to objectively evaluate the relationship between muscle fatty infiltration and inflammation/metabolic markers. Declarations Author Contribution Y.X.X. and Q.W.S. conceived of the studyY.X.X and C.W.Z. draft the manuscript.R.H. and Q.Y.Y. participated in the design of the study.Q.W.S. and S.C. performed the manuscript editing.All of the authors have given final approval of the version to be published and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.Y.X.X and C.W.Z. contributed equally to this work. References Roberto CA, Swinburn B, Hawkes C, Huang TT, Costa SA, Ashe M, Zwicker L, Cawley JH, Brownell KD (2015) Patchy progress on obesity prevention: emerging examples, entrenched barriers, and new thinking. Lancet 385:2400-2409. doi: 10.1016/S0140-6736(14)61744-X Jiang L, Rong J, Wang Y, Hu F, Bao C, Li X, Zhao Y (2011) The relationship between body mass index and hip osteoarthritis: a systematic review and meta-analysis. 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JAMA 309:2240-2249. doi: 10.1001/jama.2013.5835 Sabench Pereferrer F, Molina Lopez A, Vives Espelta M, Raga Carceller E, Blanco Blasco S, Buils Vilalta F, Paris Sans M, Pinana Campon ML, Hernandez Gonzalez M, Sanchez Marin A, Del Castillo Dejardin D (2017) Weight Loss Analysis According to Different Formulas after Sleeve Gastrectomy With or Without Antral Preservation: a Randomised Study. Obes Surg 27:1254-1260. doi: 10.1007/s11695-016-2454-z Crawford RJ, Cornwall J, Abbott R, Elliott JM (2017) Manually defining regions of interest when quantifying paravertebral muscles fatty infiltration from axial magnetic resonance imaging: a proposed method for the lumbar spine with anatomical cross-reference. BMC Musculoskel Disord 18:25. doi: 10.1186/s12891-016-1378-z Pfirrmann CW, Metzdorf A, Zanetti M, Hodler J, Boos N (2001) Magnetic resonance classification of lumbar intervertebral disc degeneration. 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Aging (Albany NY) 10:2051-2061. doi: 10.18632/aging.101529 Lassale C, Batty GD, Steptoe A, Cadar D, Akbaraly TN, Kivimaki M, Zaninotto P (2019) Association of 10-Year C-Reactive Protein Trajectories With Markers of Healthy Aging: Findings From the English Longitudinal Study of Aging. J Gerontol A Biol Sci Med Sci 74:195-203. doi: 10.1093/gerona/gly028 Lee WJ, Peng LN, Loh CH, Chen LK (2020) Sex-different associations between serum homocysteine, high-sensitivity C-reactive protein and sarcopenia: Results from I-Lan Longitudinal Aging Study. Exp Gerontol 132:110832. doi: 10.1016/j.exger.2020.110832 Agten A, Stevens S, Verbrugghe J, Eijnde BO, Timmermans A, Vandenabeele F (2020) The lumbar multifidus is characterised by larger type I muscle fibres compared to the erector spinae. Anat Cell Biol 53:143-150. doi: 10.5115/acb.20.009 Comerford MJ, Mottram SL (2001) Movement and stability dysfunction--contemporary developments. Man Ther 6:15-26. doi: 10.1054/math.2000.0388 Additional Declarations No competing interests reported. Supplementary Files TableS1.docx Cite Share Download PDF Status: Published Journal Publication published 11 Jun, 2025 Read the published version in European Spine Journal → Version 1 posted Editorial decision: Revision requested 22 Apr, 2025 Reviewers agreed at journal 22 Apr, 2025 Reviewers agreed at journal 21 Apr, 2025 Reviews received at journal 20 Apr, 2025 Reviews received at journal 20 Apr, 2025 Reviewers agreed at journal 20 Apr, 2025 Reviewers agreed at journal 19 Apr, 2025 Reviews received at journal 14 Apr, 2025 Reviewers agreed at journal 04 Apr, 2025 Reviewers invited by journal 04 Apr, 2025 Editor assigned by journal 26 Mar, 2025 Submission checks completed at journal 26 Mar, 2025 First submitted to journal 25 Mar, 2025 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. 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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-6303104","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":446625362,"identity":"ca0ac1ed-bfed-4182-aeb3-bed708754c7a","order_by":0,"name":"Yuxue Xie","email":"","orcid":"","institution":"Huashan Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yuxue","middleName":"","lastName":"Xie","suffix":""},{"id":446625363,"identity":"5bce604d-5494-4312-a39f-a517072698a5","order_by":1,"name":"Chongwen Zhan","email":"","orcid":"","institution":"Huashan Hospital","correspondingAuthor":false,"prefix":"","firstName":"Chongwen","middleName":"","lastName":"Zhan","suffix":""},{"id":446625364,"identity":"d4fe4aef-416d-4fa6-b7ca-7d15712decd5","order_by":2,"name":"Hongyue Tao","email":"","orcid":"","institution":"Huashan Hospital","correspondingAuthor":false,"prefix":"","firstName":"Hongyue","middleName":"","lastName":"Tao","suffix":""},{"id":446625365,"identity":"1956158e-70d6-40b3-983f-b71befec9abe","order_by":3,"name":"Qing Li","email":"","orcid":"","institution":"Siemens (China)","correspondingAuthor":false,"prefix":"","firstName":"Qing","middleName":"","lastName":"Li","suffix":""},{"id":446625366,"identity":"3bed05f6-2f11-4718-938a-5f5ea759f08f","order_by":4,"name":"Rong Hua","email":"","orcid":"","institution":"Huashan Hospital","correspondingAuthor":false,"prefix":"","firstName":"Rong","middleName":"","lastName":"Hua","suffix":""},{"id":446625367,"identity":"b90499d6-7645-448a-8df0-dbe454460fac","order_by":5,"name":"Qiyuan Yao","email":"","orcid":"","institution":"Huashan Hospital","correspondingAuthor":false,"prefix":"","firstName":"Qiyuan","middleName":"","lastName":"Yao","suffix":""},{"id":446625368,"identity":"a0adc60a-abc7-4c7b-ab07-7722b27148b1","order_by":6,"name":"Qiwei Shen","email":"","orcid":"","institution":"Huashan Hospital","correspondingAuthor":false,"prefix":"","firstName":"Qiwei","middleName":"","lastName":"Shen","suffix":""},{"id":446625369,"identity":"b820ff00-ba59-4c65-a5ca-3c1c6a39a21b","order_by":7,"name":"Shuang Chen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/klEQVRIiWNgGAWjYDACCSBmbACxmA8++FBhw8PP3kC0FrZkwxln0mQkew4QrYVHTZq37bCNwQ0H/Dr4Zzcfe/hzx2F5c/41zMY8Z87zMNxgYPzwMQePJXeOpRvznjlsuHPG24MP51Tc5mGc3cAsOXMbbi0GEjlm0oxthxk33DiXbPDmzG0eZpkDbMy8eLXkf5P82XbYfsONM2YSvG3neNgkEghpyWEDqjycuOF8j5kkb9sBHh5CWiRupJkBAyo9ecMNcCAn80jwHGzG6xf+GcnPgA6ztt1w/jAoKu3s7Y83H/zwEY8WJPsSYCxINBEB+A8QqXAUjIJRMApGHAAAXeBZnK8UX1YAAAAASUVORK5CYII=","orcid":"","institution":"Huashan Hospital","correspondingAuthor":true,"prefix":"","firstName":"Shuang","middleName":"","lastName":"Chen","suffix":""}],"badges":[],"createdAt":"2025-03-25 11:08:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6303104/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6303104/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00586-025-08970-2","type":"published","date":"2025-06-11T15:57:48+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":82120519,"identity":"08da0cd2-3e3c-4a78-aee0-5a3b599450af","added_by":"auto","created_at":"2025-05-07 03:16:36","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":513264,"visible":true,"origin":"","legend":"\u003cp\u003eThe flow diagram of the study.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6303104/v1/3744ad84157b0e68f1097e4a.jpeg"},{"id":82120524,"identity":"c6082698-c19d-4c76-bd1a-6048dbc37ebc","added_by":"auto","created_at":"2025-05-07 03:16:36","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":353728,"visible":true,"origin":"","legend":"\u003cp\u003eMeasurements of muscle parameters.The region of interest was placed at the contours of the multifidus (green), erector spinae (yellow), and psoas (purple) muscles manually for each axial slice from the middle-most level of the L1/2 to L5/S1 disc levels on the FF maps. The representative slice was selected from L3/4 disc level.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6303104/v1/3ba792ddcd1968e54c3c0f65.jpeg"},{"id":82120520,"identity":"1468e179-e264-4185-812a-32a6b4804f34","added_by":"auto","created_at":"2025-05-07 03:16:36","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":968082,"visible":true,"origin":"","legend":"\u003cp\u003eRepresentative fat fraction maps from a 32-years old female patient illustration changes in muscle compositional and morphological parameters one year after Bariatric surgery. The upper row are images from preoperative scan. The lower row are images from postoperative scan. A and F from L1/2 disc level; B and G from L2/3 disc level; C and H from L3/4 disc level; D and I from L4/5 disc level; E and J from L5/S1 disc level. Among these paired images, only A and F (L1/2 disc level) exhibit noticeable variations. Specifically, the preoperative fat fraction values at L1/2 disc level were higher (green) than the postoperative values (blue) for the paraspinal muscles.\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6303104/v1/d8ceb4310161cd5452afb6e6.jpeg"},{"id":84726651,"identity":"e0a134b8-7124-46fe-976c-ae1456478fa7","added_by":"auto","created_at":"2025-06-16 16:07:46","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2922752,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6303104/v1/1e325ec9-4bfa-43dd-be23-1c22a477e6be.pdf"},{"id":82120516,"identity":"39ac7aaf-9b11-4cc9-b8a9-7b4970d8c7ec","added_by":"auto","created_at":"2025-05-07 03:16:36","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":20640,"visible":true,"origin":"","legend":"","description":"","filename":"TableS1.docx","url":"https://assets-eu.researchsquare.com/files/rs-6303104/v1/bcaef72e6cec15ff05033ef1.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"The Longitudinal Variations of Paraspinal Muscle Fatty Infiltration in Obese Patients after Bariatric Surgery","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMorbid obesity and its associated comorbidities are major global public health issues, leading to serious physical and musculoskeletal disorders [1\u0026ndash;4]. Bariatric surgery, in conjunction with nutritional education and close follow-up, has been widely accepted as the most effective treatment for weight reduction and related issues[5, 6]. Unfortunately, bariatric surgery is also associated with complications. The best acknowledged one complication is that bariatric surgery adversely affects skeletal health, particular for the spine [7\u0026ndash;14]. While compared to the deeply insight of detrimental impact on vertebrae health, the effect of bariatric surgery on paraspinal muscle condition remains unclear for obese patients[15]. Study has shown that rapid and substantial weight loss can lead to significant losses in lean mass after Bariatric surgery [16]. Understanding this longitudinal relationship is important in developing an effective approach for exercise guiding after surgery the in obese patients after bariatric surgery[17].\u003c/p\u003e \u003cp\u003eDecline in paraspinal muscle health has been characterized by increased intramuscular fat and decreased size (muscle atrophy)[18]. Various quantitative MRI methods have been developed to objectively assess the degree of muscle fatty infiltration. Recently, the Q-Dixon method has gained popularity for its application in musculoskeletal MRI, particularly for calculating muscle fat fraction (FF) value of the muscles. This accurate and noninvasive imaging tool, combined with bariatric surgery\u0026rsquo;s capacity for rapid weight loss, offers a unique opportunity to evaluate the muscle change pattern based on longitudinal design.\u003c/p\u003e \u003cp\u003eSince strong correlations have been demonstrated between age and muscle fatty infiltration have been established across different anatomic regions[19, 20], the present study included young adults to explore weight-related paraspinal muscle fatty infiltration. The purpose of this longitudinal study was to quantitatively examine weight-related variation in the compositional and morphological parameters of different paraspinal muscles using the Q-Dixon sequence in obese patients and to investigate the change pattern in these parameters one year after bariatric surgery.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eParticipants\u003c/h2\u003e \u003cp\u003eThis prospective cohort study was approved by the Institutional Review Board in our hospital, and informed consent was obtained from all participants. Consecutive patients with obesity (BMI\u0026thinsp;\u0026ge;\u0026thinsp;30kg/m\u003csup\u003e2\u003c/sup\u003e) admitted to the Department of General Surgery Center for bariatric surgery between November 2022 and May 2023 were invited to participate. The bariatric procedures were conducted under the supervision of a single senior bariatric surgeon. Healthy controls were recruited through the health management center of our hospital. Inclusion criteria were age 20\u0026ndash;50 years to exclude the age-related variations; stated willingness and ability to participate and follow the research protocol. Exclusion criteria included conventional lumbar MRI findings of qualitative anatomic variations, spinal lesions, lumbar spondylolisthesis, vertebral fractures, and end-plate osteochondritis; a history of spine surgery or trauma; ankylosing spondylitis, rheumatologic disorders, and muscular dystrophy; severe infections or dysfunctions (heart, lung, liver, and kidney) that pose a high risk to trial safety or individuals with life-threatening diseases or serious unstable underlying conditions; contraindications for MR examination; a history of systematic paravertebral muscle function exercises within the past 6 months; and incomplete MRI data. Age and gender were matched between the obese and control group. The final sample included 104 participants (52 in each group). A total of 30 patients (57.7%) finished all the postoperative clinical and MRI examinations at one-year follow-up visits (Figure. 1).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSurgical Techniques\u003c/h3\u003e\n\u003cp\u003eStandardized bariatric surgery was performed[21]. After pneumoperitoneum was established, a 12 mm puncture was inserted into the umbilicus, and a 5 mm puncture was inserted under the xiphoid process, in the right upper quadrant, and in the left upper quadrant. The greater curvature of the stomach is mobilized, extending from the anterior pyloric vein to the complete fundus of the stomach. Medtronic Tri-Staple intelligent cutting and closing device (purple staple cartridge: EGIA6OAMT) was used to cut and anastomose 3cm away from the pylorus. Care was taken to keep the staple line 1cm away from the His angle to prevent ischemia and obstruction at the gastroesophageal junction while fully resecting the fundus of the stomach. After the cut is completed, a Johnson \u0026amp; Johnson 3\u0026thinsp;\u0026minus;\u0026thinsp;0 barbed suture (SXMD1B405) was used for full-thickness reinforcement, securing the incision edge to minimize bleeding. The patients were then extubated and transferred back to the ward.\u003c/p\u003e\n\u003ch3\u003eClinical and Experimental Variables for Obese Group\u003c/h3\u003e\n\u003cp\u003ePreoperative and postoperative clinical variables were collected and recorded by a single surgeon, including age, sex, body mass index (BMI), waist circumference, hip circumference, waist-to-hip ratio, and total weight loss (TWL) percentage. The TWL was calculated as (pre-operative weight-follow-up weight) / pre-operative weight*100 [22]. Obesity-related experimental indices, including glycated hemoglobin, fasting blood glucose, cholesterol, high-density lipoprotein, low-density lipoprotein cholesterol, triglycerides, and high-sensitivity C-reactive protein (hs-CRP) were measured using an analyzer (Cobas 8000 c702, Roche Diagnostics, Basel, Switzerland). Glycated hemoglobin was determined by high-performance liquid chromatography (HPLC; ADAM A1c HA-8180 V, ARKRAY, Inc., Kyoto, Japan).\u003c/p\u003e\n\u003ch3\u003eMR acquisition\u003c/h3\u003e\n\u003cp\u003eLumbar MR examinations were performed using a 3.0-T MRI system (MAGNETOM Prisma, Siemens Healthineer) with a 32-channel spine matrix coil in the supine position. Scan range needed to cover the entire lumbar vertebrae (L1-S1). The imaging protocol included a sagittal T1-weighted (T1W) Turbo Spin Echo (TSE) sequence, sagittal T2W TSE sequence, axial T2W TSE sequence, axial three-dimensional T2*-corrected 6-echo Dixon volume-interpolated breath-hold examination sequence, and sagittal T2 mapping sequences. FF map and T2 map reconstruction were automatically completed. Detailed parameters of each sequence are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\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\u003eMRI sequences and parameters.\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=\"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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSag T2W\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSag T1W\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAxi T2W\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eAxi Q-Dixon\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSag T2 mapping\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e460\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e10.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.04, 2.5, 3.96, 5.42, 6.88, 8.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e10.5, 21, 31.5, 42, 52.5, 63\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo. of slices per slab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eslice thickness, mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSpace between slices\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e/\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eField of view, mm2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e280\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e280\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e380\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e250\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePhase encoding direction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eH\u0026thinsp;\u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eH\u0026thinsp;\u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eA\u0026thinsp;\u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eA\u0026thinsp;\u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eA\u0026thinsp;\u0026gt;\u0026thinsp;\u0026gt;\u0026thinsp;P\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eaverages\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\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFlip angle, degrees\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e160\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e180\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBandwidth, Hz/Px\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e252\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e252\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e250\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e900\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e202\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAcquisition time, minutes: seconds\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e00:56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e00:58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e00:57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e00:18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e02:14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEcho train length\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMatrix\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e320*320\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e640*640\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e640*640\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e192*180\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e276*384\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eSag, sagittal; T2W, T2-weighted; T1W, T1-weighted; Axi, axial; TR, repetition time; TE, echo time\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eMRI image analysis\u003c/h3\u003e\n\u003cp\u003eDixon images were imported into the post-processing workstation (Syngo software version B17, Siemens Healthineers) for data extraction. Regions of interest (ROIs) were placed at the contours of the MF, ES, and psoas muscles manually for each axial slice from the middle-most level of the L1/2 to L5/S1 disc levels on the FF maps (Figure. 2)[23]. Left and right cross-sectional area (CSA) and FF values were recorded and averaged, respectively. The functional CSA (FCSA) was calculated using the formula: FCSA\u0026thinsp;=\u0026thinsp;CSA \u0026times; (1-FF%).\u003c/p\u003e \u003cp\u003eIntervertebral disc degeneration (IVDD) was evaluated from L1-L2 to L5-S1 disc levels using the Pfirrmann grading system on T2W images[24] and quantified on T2mapping images to calculate T2 value. All ROIs for all participants were independently and blindly segmented by two radiologists (with 12 and 7 years of experience in skeletal muscle radiology, respectively) to calculate inter-observer and intra-observer agreement.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eData analysis was performed using R Language (R version 3.5.1; \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.r-project.org/\u003c/span\u003e\u003cspan address=\"http://www.r-project.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e). Categorical variables were compared using Chi-square or Fisher\u0026rsquo;s exact test. Non-parametric continuous variables were compared using Mann-Whitney U test or Kruskal-Wallis test according to how many variables were compared at a time. The Parameters of the study samples were presented as mean (\u0026plusmn;) standard deviation for continuous variables and absolute counts. An alpha value of \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was accepted as statistically significant. Pearson correlation tests were conducted to explore the relationship between the variations of muscle FF and clinical parameters from preoperative to postoperative data. Correlations were classified as follows: Pearson correlation coefficient (PCC)\u0026thinsp;\u0026gt;\u0026thinsp;0.6, extremely strong; 0.6\u0026ndash;0.4, moderate; \u0026lt; 0.4 weak, and no correlation. The Friedman M test was used to compare muscle FF among different lumbar disc levels. The intraclass correlation coefficients (ICCs) of FF and CSA were calculated using a two-way mixed absolute agreement model. The ICCs were graded as follows: excellent reliability, 0.75\u0026thinsp;\u0026le;\u0026thinsp;ICC\u0026thinsp;\u0026le;\u0026thinsp;1; fair to good, 0.4\u0026thinsp;\u0026le;\u0026thinsp;ICC\u0026thinsp;\u0026lt;\u0026thinsp;0.75; and poor, 0\u0026thinsp;\u0026le;\u0026thinsp;ICC\u0026thinsp;\u0026lt;\u0026thinsp;0.4).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe ICCs results were excellent, indicating minimal interobserver variability, and the means of both measurements were used for further analysis.\u003c/p\u003e \u003cp\u003eFifty-two obese patients (45 women, mean age 33.15\u0026thinsp;\u0026plusmn;\u0026thinsp;6.51 years old) and 52 controls (45 women, mean age 33.52\u0026thinsp;\u0026plusmn;\u0026thinsp;3.43 years old) with normal weight were included after matching for age and gender. Obese patients and control groups were similar in height (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.73), while the obese group was much heavier than the control group (37.66\u0026thinsp;\u0026plusmn;\u0026thinsp;5.05 vs. 24.05\u0026thinsp;\u0026plusmn;\u0026thinsp;3.00 kg/m\u003csup\u003e2\u003c/sup\u003e, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Finally, 30 patients returned for MRI and clinical analysis at one-year follow-up. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e details the sociodemographic and clinical characteristics at baseline and one year postoperatively for patients with complete follow-up. Mean BMI showed significant decreases from preoperative to postoperative data (38.21\u0026thinsp;\u0026plusmn;\u0026thinsp;4.74 vs. 26.27\u0026thinsp;\u0026plusmn;\u0026thinsp;3.20 kg/m\u003csup\u003e2\u003c/sup\u003e, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The postoperative EWL was 99.5\u0026thinsp;\u0026plusmn;\u0026thinsp;24.7%. The postoperative TWL was 30.8\u0026thinsp;\u0026plusmn;\u0026thinsp;6.9%.\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\u003eGeneral and biochemical indicators comparisons between preoperative and postoperative measurements.\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=\"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=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePostoperative\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeight (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e109.1\u0026thinsp;\u0026plusmn;\u0026thinsp;20.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e74.1\u0026thinsp;\u0026plusmn;\u0026thinsp;13.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (kg/m2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e38.2\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e24.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWaist circumference (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e116.9\u0026thinsp;\u0026plusmn;\u0026thinsp;12.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e88.1\u0026thinsp;\u0026plusmn;\u0026thinsp;8.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHip circumference (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e119.2\u0026thinsp;\u0026plusmn;\u0026thinsp;9.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e94.3\u0026thinsp;\u0026plusmn;\u0026thinsp;7.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWaist-to-hip ratio\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.98\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.79\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGlycated hemoglobin (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e6.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e5.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFasting blood glucose (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e5.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e4.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCholesterol (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e4.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e4.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLDL-C(mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e3.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHDL-C(mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTriglyceride (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHs-CRP (mg/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eData were reported as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations for continuous variables. \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was reported as Bold. BMI, body mass index; WBC, white blood cell; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; Hs-CRP, high-sensitivity C-creative protein.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eBolded \u003cem\u003eP\u003c/em\u003e value indicates a significant difference between groups.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eMuscle Parameters Comparisons between Patients and Controls\u003c/h3\u003e\n\u003cp\u003eMuscle parameters for FF, CSA, and FCSA were calculated and compared between the control group and obese group at baseline (Tables\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). When compared at the same disc level and muscle specifically, obese patients had significantly higher mean FF for all three paraspinal muscles at all disc levels (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001, Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). However, CSA showed different weight-related variation in different muscles at different levels. For the ES, obese patients demonstrated significant higher CSA than controls at all levels (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). For the MF and psoas, there was also a trend of harboring higher CSA in obese patients, yet the differences at upper levels were not statistically significant (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05, Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). These differences were more pronounced at L4/5 and L5-S1 disc levels (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05, Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\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\u003eMuscle compositional and morphological parameters comparisons between obese group and control group.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"11\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eES\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eMF\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c11\" namest=\"c9\"\u003e \u003cp\u003ePsoas\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eControl group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eObese group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eControl group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eObese group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eControl group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eObese group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eFF (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL1/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11.7\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL2/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.6\u0026thinsp;\u0026plusmn;\u0026thinsp;2.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e6.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e7.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e 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colname=\"c4\"\u003e \u003cp\u003e13.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7.7\u0026thinsp;\u0026plusmn;\u0026thinsp;4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e6.6\u0026thinsp;\u0026plusmn;\u0026thinsp;3.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e 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align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL4/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e 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\u003cp\u003e11.1\u0026thinsp;\u0026plusmn;\u0026thinsp;4.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.375\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL2/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.6\u0026thinsp;\u0026plusmn;\u0026thinsp;4.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.679\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e4.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.62\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL3/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.607\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e6.3\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e7.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL4/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.6\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e8.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e9.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL5/S1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e9.0\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e10.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"11\"\u003eFF, fat fraction; CSA, cross-sectional area; FCSA, functional CSA; ES, erector spinae; MF, multifidus muscle. Bolded \u003cem\u003eP\u003c/em\u003e value indicates a significant difference between groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eLumbar IVVD Comparisons between Patients and Controls\u003c/h2\u003e \u003cp\u003eThe intervertebral disc parameters were compared in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. Severe IVDD was more common in obese patients than that in the control group (based on both Pfirrmann classification and T2 values (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 for all the disc level, Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Moreover, when comparing the groups level by level, these differences were more predominantly at upper levels (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001, Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\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\u003ePfirrmann classification and quantitative intervertebral disc degeneration comparisons between obese group and control group.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\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=\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eControl group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eObese group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e values\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eT2 values\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL1/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e104.2\u0026thinsp;\u0026plusmn;\u0026thinsp;20.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e85.2\u0026thinsp;\u0026plusmn;\u0026thinsp;16.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL2/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e102.4\u0026thinsp;\u0026plusmn;\u0026thinsp;20.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e89.3\u0026thinsp;\u0026plusmn;\u0026thinsp;17.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL3/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e97.5\u0026thinsp;\u0026plusmn;\u0026thinsp;24.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e86.5\u0026thinsp;\u0026plusmn;\u0026thinsp;23.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL4/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e80.5\u0026thinsp;\u0026plusmn;\u0026thinsp;28.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e68.2\u0026thinsp;\u0026plusmn;\u0026thinsp;20.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL5/S1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e70.3\u0026thinsp;\u0026plusmn;\u0026thinsp;25.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e56.1\u0026thinsp;\u0026plusmn;\u0026thinsp;20.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003ePfirrmann\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL1/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL2/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL3/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.03\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL4/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e3.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eL5/S1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e4.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eBolded \u003cem\u003eP\u003c/em\u003e value indicates a significant difference between groups.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eMuscle and IVDD Measurements Change Pattern One Year Follow Bariatric Surgery\u003c/h2\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e showed the variations of FF, CSA, and FCSA at one year after the bariatric surgery for the three muscles. Specifically, FF of ES and MF showed significant improvements at the L1/2-disc level (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Furthermore, these FF variations at L1/2-disc level didn\u0026rsquo;t show any correlations with weight loss (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). The psoas didn\u0026rsquo;t report any reduction in FF values at any disc levels. For the CSA, the three muscles displayed different pattern after weight loss: the ES CSA showed significant reductions at all disc levels, while the MF and psoas showed on reduction except at the L4/5 and L5/S1 disc levels.\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\u003eChange pattern of muscle compositional and morphological parameters one year after Bariatric surgery.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003eES\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003eMF\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c12\" namest=\"c10\"\u003e \u003cp\u003ePsoas\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePostoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003ePostoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003ePostoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"4\" nameend=\"c2\" namest=\"c1\" rowspan=\"5\"\u003e \u003cp\u003eFF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL1/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e12.3\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e\u003cb\u003e0.049\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL2/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.90\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL3/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9.6\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.47\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL4/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10.3\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9.8\u0026thinsp;\u0026plusmn;\u0026thinsp;3.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL5/S1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e11.6\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10.8\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.0\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"4\" nameend=\"c2\" namest=\"c1\" rowspan=\"5\"\u003e \u003cp\u003eCSA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL1/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e19.2\u0026thinsp;\u0026plusmn;\u0026thinsp;5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.5\u0026thinsp;\u0026plusmn;\u0026thinsp;5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.6\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL2/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e14.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL3/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.7\u0026thinsp;\u0026plusmn;\u0026thinsp;4.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e11.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.0\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e8.6\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e7.6\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL4/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8.8\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003e0.003\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e11.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e9.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e0.04\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL5/S1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.0\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e11.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e9.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"4\" nameend=\"c2\" namest=\"c1\" rowspan=\"5\"\u003e \u003cp\u003eFCSA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL1/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.6\u0026thinsp;\u0026plusmn;\u0026thinsp;4.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.4\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL2/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL3/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e14.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e11.1\u0026thinsp;\u0026plusmn;\u0026thinsp;4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e8.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e7.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.29\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL4/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e10.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e8.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e0.03\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eL5/S1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e10.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e8.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"12\"\u003eFF, fat fraction; CSA, cross-sectional area; FCSA, functional CSA; ES, erector spinae; MF, multifidus muscle. \u003cem\u003eP\u003c/em\u003e value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 is reported as bold.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eContrary to the muscle parameters, none of the discs showed any improvements after bariatric surgery (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05, Table S1).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eCorrelations of the Variations between Muscle fatty infiltration and Clinical Variables\u003c/h2\u003e \u003cp\u003eWith weight loss one year after surgery, the FF variations of ES and MF at the L1/2-disc level didn\u0026rsquo;t show any correlations with the variations of weight (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). While the FF variations showed significant correlations with the variations of the hs-CRP (PCC = -0.35, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02). Other obesity-related laboratory indices did not show any correlations with the variations of muscle fatty infiltration (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, we evaluated weight-related alterations in the compositional and morphological parameters of back extensor muscles and IVDD by comparing with non-obese controls in cross-sectional design as well as comparing between preoperative and postoperative data in longitudinal design using quantitative MRI in young obese adults. Our findings demonstrated heterogenous weight-related changes in muscle fat infiltration and size, which are crucial for understanding the paraspinal muscle health in obese patients. Moreover, the relationships between MF and ES muscle fatty infiltration variations at upper level and the experimental parameters surpassed that muscle composition can be affected by the inflammatory variables in obese patients. These links inspire that further research may need lay more emphasis to investigate the role of inflammatory and metabolic variables in muscle health among patients with morbid obesity.\u003c/p\u003e \u003cp\u003eIt has been widely acknowledged that paraspinal muscle fatty infiltration, and IVDD are significantly associated with obesity[25, 26]. Numerous studies have reported that obesity can be associated with muscle fatty infiltration. Study by Pinzhen Chen et al[27] indicated that people different age and gender demonstrated muscle fatty infiltration to various extents based on Dixon imaging. These pieces of information may prove valuable value of Dixon in guiding experiments aimed at mitigating muscle fatty infiltration. Our results align with the broader finding that regional changes in muscle fatty infiltration occur concurrently with obesity and manifest differently depending on anatomical location.\u003c/p\u003e \u003cp\u003eAlong with higher FF value (correspond to weaker function) is larger CSA (stronger function) of the paraspinal muscles for patients with obesity, which are contradictory for paraspinal muscle function. Therefore, we introduced the FCSA, representative as lean muscle CSA and calculated as CSA*(1-FF), to serve as a more proper parameter to characterize the muscle function[27]. As a result, FCSA was significantly higher in obese patient than in controls, indicating superior muscle function in the obese cohort. This novel finding led us to suspect a similarity to bone adaptations observed in obesity-related studies, where obese patients exhibit higher bone density due to mechanical loading[28, 29]. Therefore, our results on obesity-related muscle parameters complement existing knowledge on spinal health variations in obese patients.\u003c/p\u003e \u003cp\u003eHigher fatty infiltration and muscle size, as well as severer IVDD, are relatively acceptable in individuals with obesity. While these findings are somewhat expected, many obese patients are curious about whether muscle fatty infiltration and IVDD can be reversed following remarkable weight-loss. This is a crucial consideration when guiding postoperative exercise regimens. However, the literature on the extent and significance of these changes in obese patients remains inconclusive. To our knowledge, this study is the first one to report the pattern of muscle variations following remarkable weight-loss one year after bariatric surgery. Our primary findings indicated that longitudinal variations of paraspinal muscles is influenced by disc level and muscle type. We found that obese participants experienced significant improvement in muscle fatty infiltration in MF and ES only at the L1/2-disc level, while the psoas did not show any significant improvements. With weight loss, relief from weight-bearing should theoretically be more pronounced from upper to lower levels. However, our results are intriguing as they show that improvement of fatty infiltration occurred only at the upper levels for MF and ES, but not at the lower levels. This suggests that improvements in muscle fatty infiltration following bariatric surgery may not solely be attributed to the relief from weight-bearing. Throughout the document, commonly suspected factors include not only mechanical unloading and also the roles of hormones, the inflammatory, and metabolic variables[30]. Among these factors associated with muscle health, substantial studies have recommended chronic inflammation as an activator of several molecular pathways involved in skeletal muscle wasting, leading to an imbalance between protein synthesis and catabolism[31, 32]. Our further correlation analysis between obesity-related laboratory indices and muscle fatty infiltration supports these findings. Specifically, improvements in hs-CRP, showed significantly moderate correlations with decrease of FF value in ES and MF at the L1/2-disc level. Consistent with our results, several previous studies have documented relationships between hs-CRP and muscle health[33, 34]. Although the potential underlying mechanisms of this association remain uncertain, the preliminary results inspire that greater attention need to be laid on the inflammatory markers in patients with morbid obesity based on our non-invasive Dixon method and longitudinal design.\u003c/p\u003e \u003cp\u003eWe also observed disparities in weight-related muscle atrophy. Interestingly, our study suggests that ES muscle size is more susceptible to weight-related mass decrease than MF. The underlying reason may be due to the significantly smaller proportion of type I muscle fibers in lumbar ES compared to MF[35]. Muscle fiber type characteristics are crucial determinants of muscle function and metabolic capacity. The MF, severing as a local stabilizer, contains higher proportion of slow type I fibers compared to ES, which functions as a global mobilizer based on mechanical properties and morphological features [36]. Specifically, the MF contains a higher proportion of slow, fatigue-resistant type I fibers, which are essential for sustained activity necessary to stabilize the [36]. On the contrary, the ES contains higher proportions of fast-contracting fibers to counterbalance forces acting on the body, making it more susceptible to weight-bearing. These findings concerning muscle fatty infiltration change patterns and their associations with inflammatory markers should be taken into consideration when guiding the most appropriate nutrition and spine-related exercise for obese patients after surgery.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eOne year after bariatric surgery, notable alterations in muscle fatty infiltration were observed in the ES and MF at higher level, which may be linked to hs-CPR. Additionally, longitudinal non-invasive data based on Q-Dixon could serve as an effective quantitative marker to investigate changes in paraspinal muscle function in obese patients.\u003c/p\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eLimitations\u003c/h2\u003e \u003cp\u003eSeveral limitations in this study need to be acknowledged. Firstly, the follow-up period was only one year, which is relatively short. Secondly, the sample size was relatively small, so we cannot explore the relationship between the muscle quality and the experimental parameters. Future studies with longer follow-up periods and larger sample size could potentially enhance our results to analyze and understand the pathophysiology underlying these observations. Secondly, we didn\u0026rsquo;t include a control group undergoing non-surgical weight loss, such as lifestyle-intensive medical management. Since our purpose was not to explore the surgery-related muscle or IVDD change pattern, this comparison was not explored. Thirdly, we didn\u0026rsquo;t explore the muscle strength due to the absence of evidence suggesting muscle function frailty in our daily clinical practice, given that the patients are young adults with massive muscle mass. Lastly, we didn\u0026rsquo;t obtain muscle histological tissue to establish a definitive reference point, citing ethical constraints. Further research involving histological data on muscle is necessary to objectively evaluate the relationship between muscle fatty infiltration and inflammation/metabolic markers.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eY.X.X. and Q.W.S. conceived of the studyY.X.X and C.W.Z. draft the manuscript.R.H. and Q.Y.Y. participated in the design of the study.Q.W.S. and S.C. performed the manuscript editing.All of the authors have given final approval of the version to be published and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.Y.X.X and C.W.Z. contributed equally to this work.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eRoberto CA, Swinburn B, Hawkes C, Huang TT, Costa SA, Ashe M, Zwicker L, Cawley JH, Brownell KD (2015) Patchy progress on obesity prevention: emerging examples, entrenched barriers, and new thinking. 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Man Ther 6:15-26. doi: 10.1054/math.2000.0388\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"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":"Q-Dixon, Longitudinal, fatty infiltration, Paraspinal muscle, Bariatric surgery","lastPublishedDoi":"10.21203/rs.3.rs-6303104/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6303104/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose:\u003c/strong\u003e The effect of bariatric surgery on the bone density reduction is well documented, while its effect on the paraspinal muscle remains unclear.\u003cstrong\u003e \u003c/strong\u003eThe purpose of this study is to analyze changes in muscle fatty infiltration one year after bariatric surgery in young obese adults.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eFifty-two obese patients (38 female, BMI = 43.5± 5.6 kg/m\u003csup\u003e2\u003c/sup\u003e)\u003cstrong\u003e \u003c/strong\u003ewho underwent Bariatric surgery and 52 age- and sex-matched controls with normal weight (BMI = 23.5±5.6 kg/m\u003csup\u003e2\u003c/sup\u003e) at baseline. Forty patients came back at one-year follow-up. Quantitative Dixon and T2 mapping MRI were employed to evaluate the paraspinal muscles and intervertebral disc degeneration respectively. Fat fraction (FF) and cross-sectional area (CSA) of multifidus muscle (MF), erector spinae (ES), and psoas muscles and T2 value of intervertebral disc at various disc levels were taken and compared between patients and controls, as well as preoperatively and postoperatively for the patients. Furthermore, the correlations of these MRI variables from preoperative to the postoperative and clinical variables were explored. Pearson correlation was used to analysis the link between the variables of muscle MRI parameters and weight as well as obesity-related experimental indices from preoperative to the postoperative.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eObese patients exhibited increased FF values in three muscles, increased CSA in the ES at all disc levels (\u003cem\u003eP\u003c/em\u003e \u0026lt;0.001). While for the MF and psoas, only L4/5 and L5/S1 disc levels demonstrated significant increased CSA value in patient group (\u003cem\u003eP\u003c/em\u003e\u0026lt;0.05). Patient group displayed significantly lower T2 values and higher Pfirrmann classification of all the five intervertebral discs (all \u003cem\u003eP \u003c/em\u003e\u0026lt; 0.05), particularly in high levels. One year postoperatively, FF values of the ES and MF significantly decreased only at L1/2-disc level (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05). These decreases were not significantly correlated with weight loss (all \u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05). While a link between variables of high-sensitivity C-reactive protein and FF decrease of the ES and MF from preoperative to postoperative were evidenced (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions \u003c/strong\u003eSignificant improvements in muscle fatty infiltration were observed postoperatively in the ES and MF at higher level, which may be linked to the improvements of high-sensitivity C-reactive protein.\u003c/p\u003e","manuscriptTitle":"The Longitudinal Variations of Paraspinal Muscle Fatty Infiltration in Obese Patients after Bariatric Surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-07 03:16:31","doi":"10.21203/rs.3.rs-6303104/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-04-23T02:07:33+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"103804667932045337580061155595087683934","date":"2025-04-22T05:03:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"240653989451138457826378437857659320860","date":"2025-04-21T09:50:42+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-21T03:42:31+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-20T21:01:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"323664119686765806473188039919943243279","date":"2025-04-20T19:40:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"302593909700721382977244732277105119558","date":"2025-04-20T02:55:25+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-14T09:31:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"137147428162856199735762344871191605794","date":"2025-04-04T08:44:13+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-04-04T07:09:40+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-26T05:57:28+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-26T05:55:59+00:00","index":"","fulltext":""},{"type":"submitted","content":"European Spine Journal","date":"2025-03-25T10:53:14+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":"32d9bf83-75c7-4522-b2cd-5c33482249d7","owner":[],"postedDate":"May 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-06-16T16:04:39+00:00","versionOfRecord":{"articleIdentity":"rs-6303104","link":"https://doi.org/10.1007/s00586-025-08970-2","journal":{"identity":"european-spine-journal","isVorOnly":false,"title":"European Spine Journal"},"publishedOn":"2025-06-11 15:57:48","publishedOnDateReadable":"June 11th, 2025"},"versionCreatedAt":"2025-05-07 03:16:31","video":"","vorDoi":"10.1007/s00586-025-08970-2","vorDoiUrl":"https://doi.org/10.1007/s00586-025-08970-2","workflowStages":[]},"version":"v1","identity":"rs-6303104","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6303104","identity":"rs-6303104","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}