The Pelvic Incidence Stratified Sagittal Spinopelvic Alignment in Asymptomatic Chinese Population With Different Age Groups

Study Design: Cross-sectional study. Objective: To provide the age- and pelvic incidence-related variations of sagittal alignment in asymptomatic Chinese population. Methods: This study recruited asymptomatic adult subjects. All subjects undertook the standing whole spinal radiograph and the sagittal parameters were measured: sagittal vertical axis (SVA), T1 pelvic angle (TPA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI) and pelvic tilt (PT). All subjects were divided into young, middle aged and elderly groups, then each age group was further divided into 5 subgroups (very low, low, average, high and very high) based on PI values. The relations between PI, age and other parameters were evaluated. The differences in sagittal parameters of each PI subgroup were compared. Results: 546 subjects were included with an average age of 38.6 years (18 to 81). The number of subjects over 70 years and with very low PI was relatively small. The average of PI, TPA, PT and LL were 45.9° ± 8.4°, 6.4° ± 6.2°, 11.9° ± 6.6° and 49.2° ± 10.1°, respectively. SVA, TPA, TK and PT increased with age ( P < 0.05), while SVA, TPA, PT, PI-LL also increased with PI ( P < 0.05). LL, PT, TPA, PI-LL and LL-TK were different among the 5 PI subgroups ( P < 0.05). However, the values of LL in elderly subjects with high and very high PI were similar. Conclusion: The age- and PI-related variations in sagittal alignment of Chinese population were provided. The sagittal parameters were significantly influenced by age and PI. The individual pelvic morphology should be carefully considered during the assessment and restoration of sagittal balance.

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Sagittal alignment based on inflection point and its differences according to age groups

Journal of Orthopaedic Surgery ◽

10.1177/2309499020904615 ◽

2020 ◽

Vol 28 (1) ◽

pp. 230949902090461

Author(s):

Moon Soo Park ◽

Seong-Hwan Moon ◽

Tae-Hwan Kim ◽

Jae Keun Oh ◽

Seung Jin Lee ◽

...

Keyword(s):

Pelvic Incidence ◽

Sagittal Plane ◽

Sagittal Alignment ◽

Age Groups ◽

Vertical Axis ◽

Sacral Slope ◽

Sagittal Vertical Axis ◽

Inflection Points ◽

Lumbar Segment ◽

Cervical Segment

Purpose: We have always used the standard anatomical landmark vertebrae to measure the sagittal alignment. Instead, scoliosis has been evaluated by the end vertebrae in the coronal plane. There have been clinical studies to investigate sagittal alignment on the end vertebrae of inflection points (IPs). The purpose is to determine sagittal alignment based on IPs and to elucidate the changes while considering age groups. Methods: We identified the most titled vertebrae in the sagittal plane to define the end vertebrae of S1, thoracolumbar and cervicothoracic IPs and to measure the Cobb angles of sacral slope, functional lumbar, thoracic, cervical segment between them, and the McGregor’s line, and the IP distances from the C2 plumb line to the point bisecting the upper end plate of the IPs, in addition to S1. Results: The most common thoracolumbar and cervicothoracic IPs were L2 and T1, respectively. However, the next most common cervicothoracic IP changed from T2 in the youngest to C7 in the oldest age group. The sagittal angles decreased at the sacral slope and functional lumbar segment but not the functional thoracic segment and functional cervical segment. Similarly, the distance increased at the C2 sagittal vertical axis (SVA) distance to S1 and thoracolumbar IP distance but not at the cervicothoracic IP distance. There was no difference in the pelvic incidence among age groups. Conclusion: The sagittal Cobb angles based on the IPs decreased at the sacral slope and functional lumbar segment in the older adults. Consequently, the C2 SVA distance to S1 and thoracolumbar IP distance increased.

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Normal Age-Adjusted Sagittal Spinal Alignment Is Achieved with Surgical Correction in Adolescent Idiopathic Scoliosis

Asian Spine Journal ◽

10.4184/asj.2017.11.5.770 ◽

2017 ◽

Vol 11 (5) ◽

pp. 770-779 ◽

Cited By ~ 1

Author(s):

Subaraman Ramchandran ◽

Norah Foster ◽

Akhila Sure ◽

Thomas J. Errico ◽

Aaron J. Buckland

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Lumbar Lordosis ◽

Thoracic Kyphosis ◽

Pelvic Incidence ◽

Sagittal Alignment ◽

Vertical Axis ◽

Surgical Correction ◽

Sagittal Vertical Axis

<sec><title>Study Design</title>Retrospective analysis.</sec><sec><title>Purpose</title>Our hypothesis is that the surgical correction of adolescent idiopathic scoliosis (AIS) maintains normal sagittal alignment as compared to age-matched normative adolescent population.</sec><sec><title>Overview of Literature</title>Sagittal spino-pelvic alignment in AIS has been reported, however, whether corrective spinal fusion surgery re-establishes normal alignment remains unverified.</sec><sec><title>Methods</title>Sagittal profiles and spino-pelvic parameters of thirty-eight postsurgical correction AIS patients ≤21 years old without prior fusion from a single institution database were compared to previously published normative age-matched data. Coronal and sagittal measurements including structural coronal Cobb angle, pelvic incidence, pelvic tilt, thoracic kyphosis, lumbar lordosis, sagittal vertical axis, C2–C7 cervical lordosis, C2–C7 sagittal vertical axis, and T1 pelvic angles were measured on standing full-body stereoradiographs using validated software to compare preoperative and 6 months postoperative changes with previously published adolescent norms. A sub-group analysis of patients with type 1 Lenke curves was performed comparing preoperative to postoperative alignment and also comparing this with previously published normative values.</sec><sec><title>Results</title>The mean coronal curve of the 38 AIS patients (mean age, 16±2.2 years; 76.3% female) was corrected from 53.6° to 9.6° (80.9%, <italic>p</italic><0.01). None of the thoracic and spino-pelvic sagittal parameters changed significantly after surgery in previously hypo- and normo-kyphotic patients. In hyper-kyphotic patients, thoracic kyphosis decreased (<italic>p</italic>=0.003) with a reciprocal decrease in lumbar lordosis (<italic>p</italic>=0.01), thus lowering pelvic incidence-lumbar lordosis mismatch mismatch (<italic>p</italic>=0.009). Structural thoracic scoliosis patients had slightly more thoracic kyphosis than age-matched patients at baseline and surgical correction of the coronal plane of their scoliosis preserved normal sagittal alignment postoperatively. A sub-analysis of Lenke curve type 1 patients (n=24) demonstrated no statistically significant changes in the sagittal alignment postoperatively despite adequate coronal correction.</sec><sec><title>Conclusions</title>Surgical correction of the coronal plane in AIS patients preserves sagittal and spino-pelvic alignment as compared to age-matched asymptomatic adolescents.</sec>

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Effect of sagittal imbalance on functional disability in patients with degenerative spondylolisthesis

International Journal of Research in Orthopaedics ◽

10.18203/issn.2455-4510.intjresorthop20195794 ◽

2019 ◽

Vol 6 (1) ◽

pp. 31

Author(s):

Ramdas Maloth

Keyword(s):

Functional Disability ◽

Pelvic Incidence ◽

Sagittal Plane ◽

Degenerative Spondylolisthesis ◽

Vertical Axis ◽

P Value ◽

Sagittal Imbalance ◽

Sagittal Vertical Axis ◽

Cross Sectional ◽

Digital Radiograph

Background: Deformity of spine in sagittal plane is a major cause of pain and disability among patients presenting with low back pain to spine clinic. We have studied the effect of spinal sagittal imbalance on functional disability in these patients.Methods: Cross sectional observational study in 50 patients with degenerative spondylolisthesis of more than 45 years age group study done in period of1 years. Subjects underwent standing lateral radiographs of the spine in a relaxed position, facing forward, with their knees maximally extended and their arms raised horizontally forward resting on a support. 2 radiographic films are stitched at baseline using digital radiograph operating console (DROC) software.Results: In our study out of 50 patients we observed female preponderance, female:male 3:1, degenerative spondylolisthesis more commonly involves L4-L5 level (46 patients). 58% of patients with severe degenerative spondylolisthesis. There is significant correlation between sagittal vertical axis (SVA) and severity (p=0.015) in both grade 1 and grade 2 DS, there is significant correlation between pi and functional disability (p=0.001 and 0.010 respectively) it is found that pelvic tilt with p=0.02 and sagittal vertical axis with p value 0.036 are the two most significant variables at the end of backward elimination analysis.Conclusions: Sagittal imbalance is seen in degenerative spondylolisthesis which needs further evaluation with spinopelvic parameters. Pelvic incidence and sagittal vertebral axis are important determinants of functional disability in patients with degenerative spondylolisthesis. Individuals with high pelvic incidence and more lumbo pelvic kyphosis showed more functional disability compared to others.

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Beyond Pelvic Incidence–Lumbar Lordosis Mismatch: The Importance of Assessing the Entire Spine to Achieve Global Sagittal Alignment

Global Spine Journal ◽

10.1177/2192568217699405 ◽

2017 ◽

Vol 7 (6) ◽

pp. 536-542 ◽

Cited By ~ 8

Author(s):

Robert K. Merrill ◽

Jun S. Kim ◽

Dante M. Leven ◽

Joung Heon Kim ◽

Samuel K. Cho

Keyword(s):

Lumbar Lordosis ◽

Pelvic Incidence ◽

Adult Spinal Deformity ◽

Case Series ◽

Vertical Axis ◽

Retrospective Case ◽

Sagittal Vertical Axis ◽

Global Sagittal Alignment ◽

Sagittal Parameters ◽

Combined Parameters

Study Design: Retrospective case series. Objective: To investigate which sagittal parameters contribute to a normal sagittal vertical axis (SVA) when there is a pelvic incidence-lumbar lordosis (PI-LL) mismatch >10° following adult spinal deformity (ASD) correction. Methods: We performed a retrospective review of ASD patients with >5 levels fused. Sagittal measurements between cohorts of postoperative PI-LL >10° and PI-LL<10° were compared. We correlated SVA to pelvic tilt (PT), thoracic kyphosis (TK), PI-LL, cervical lordosis (CL), and correlated the pre- to postoperative change in SVA to change in PT, change in TK, change in PI-LL, and change in CL. We also correlated SVA and the change in SVA to combined parameters of ((PI-LL) − PT + TK). Results: We analyzed 52 patients with a mean age of 59 ± 16 years. In patients with a postoperative SVA <5cm, a smaller TK was seen when PI-LL >10° than when PI-LL<10° (15.45° vs 33.04°, P = .0004). Additionally, PT was larger when PI-LL >10° than when PI-LL <10° (25.73° vs 19.07°, P = .006). SVA correlated better with ((PI-LL) − PT + TK) ( R2 = 0.51) than with PI-LL alone ( R2 = 0.33). Lastly, there was no significant correlation between change in pre- to postoperative SVA with change in TK for all cases ( P = .73), but in cases where change in PI-LL was <10°, there was a significant correlation between change in TK and change in SVA ( P = .009). Conclusion: Our results demonstrate that PT and TK, and not just PI-LL, play an important role in maintaining sagittal balance when there is a PI-LL mismatch >10°.

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Spinopelvic Imbalance Is Associated With Increased Sway in the Center of Gravity: Validation of the “Cone of Economy” Concept in Healthy Subjects

Global Spine Journal ◽

10.1177/21925682211038897 ◽

2021 ◽

pp. 219256822110388

Author(s):

Naoki Segi ◽

Hiroaki Nakashima ◽

Kei Ando ◽

Kazuyoshi Kobayashi ◽

Taisuke Seki ◽

...

Keyword(s):

Healthy Volunteers ◽

Center Of Pressure ◽

Economic Effect ◽

Vertical Axis ◽

Cross Sectional Study ◽

Standing Balance ◽

Elderly Subjects ◽

Sagittal Vertical Axis ◽

Cross Sectional ◽

Healthy Elderly

Study Design: Cross-sectional study. Objectives: To investigate the effects of pelvic compensation on standing balance in healthy volunteers. Methods: The 180 healthy volunteers were recruited at a basic health checkup. The inclusion criteria were: 1) age ≥ 65 years, 2) underwent a whole spine radiograph and stabilometry, 3) well-balanced standing posture with a sagittal vertical axis <50 mm, and 4) a visual analog scale of lower back pain of <20 mm. Based on the pelvic incidence (PI) and lumbar lordosis (LL) mismatch, subjects were divided into harmonious (PI–LL ≤ 10°) or unharmonious (PI–LL > 10°) groups. Results: Participants in the unharmonious group were significantly older compared with the harmonious group (70.2 ± 4.4 vs. 72.0 ± 4.6 years, P < .01). The PI minus LL values were −2.2° ± 7.5° and 16.6° ± 7.0° in the harmonious and unharmonious groups, respectively ( P < .001). Anteroposterior LNG/TIME (average center of pressure sway speed) was significantly greater in the unharmonious group with both open and closed eyes (1.04 ± 0.38 cm/s vs. 1.25 ± 0.47 cm/s, P < .001 and 1.22 ± 0.54 cm/s vs. 1.58 ± 0.77 cm/s, P < .001, respectively). Lateral LNG/TIME was significantly greater in the unharmonious group only with closed eyes (1.24 ± 0.54 cm/s vs. 1.47 ± 0.79 cm/s, P = .03). Conclusions: Healthy elderly subjects with poor spinopelvic harmony had relatively unstable standing balance. The “cone of economy” was demonstrated, showing that unharmonious spinopelvic balance had a non-economic effect on standing.

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Analysis of global spine sagittal parameters in cervical spondylotic patients and asymptomatic subjects

10.21203/rs.2.21726/v1 ◽

2020 ◽

Author(s):

Liang Zhu ◽

Xiaojun Ma ◽

Qiang Shen ◽

Bao Sun ◽

Qiang Fu

Keyword(s):

Cervical Spondylosis ◽

Lumbar Lordosis ◽

Sagittal Alignment ◽

Vertical Axis ◽

Normal Group ◽

Sacral Slope ◽

Sagittal Vertical Axis ◽

Thoracic Inlet ◽

Global Sagittal Alignment ◽

Sagittal Parameters

Abstract Background: Degenerative changes associated with cervical spondylotic can result in a change of normal sagittal alignment, and this may be the initial change of kyphosis and sagittal imbalance. Few studies have analyzed the correlations between the cervical spine lordosis and global spine balance in patients with cervical spondylotic. This study is applied to investigate the characteristics and relationships of cervical and global sagittal parameters in normal adults and cervical spondylotic patients. Methods: We reviewed 46 asymptomatic control subjects (normal group, NG) and 48 cervical spondylotic patients (cervical spondylotic group, CSG), who had both cervical MRI and global radiographs obtained together, between January 2016 and September 2018. Data includes C1-2 angle, C2–7 lordosis (CL), T1 slope (T1S), thoracic inlet angle (TIA), C2–7 sagittal vertical axis (CSVA), sagittal vertical axis(SVA), thoracic-kyphosis(TK), thoracic-lumbar lordosis(TL), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS). The values were presented as the mean ± standard deviation. Student t-test and Pearson’s correlation coefﬁcient were used for statistical analysis. Probability values less than 0.05 were considered statistically signiﬁcant. Results: 1.Comparison of global sagittal parameters between the normal group and cervical spondylosis group. A total of 48 cervical spondylotic patients with an average age of 57.91±9.58 and 46 healthy people with an average age of 28.00±8.09 were recruited in our study. CL in the NG was significantly lower than CSG (P<0.05), while TK and TL were significantly lower than in the CSG(P< 0.01). However, a comparison of the NG and CSG yielded no significant differences in C1-2, TIA, TIS, LL, PT, PI, SS, CSVA, and SVA. 2.The relationship between cervical and global sagittal alignment. CL positively correlated with T1S (r=0.433) and TK (r=0.335) while negatively correlated with CSVA (r=-0.309) in cervical spondylosis group. TIA has positively correlated with T1S (r=0.376 in NG and r=0.416 in CSG) and no correlated with other parameters in both groups. Conclusions Cervical spondylosis causes changes in sagittal parameters of the cervical and thoracic spine but does not affect on lumbar and pelvic parameters. TIA is a relative constant parameter, not affected by cervical spondylotic.

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Age- and sex-specific profiles of temporal fasting plasma glucose variability in a population undergoing routine health screening

BMC Public Health ◽

10.1186/s12889-021-10367-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Agyei Helena Lartey ◽

Xiaona Li ◽

Zhongqi Li ◽

Qun Zhang ◽

Jianming Wang

Keyword(s):

Plasma Glucose ◽

Fasting Plasma Glucose ◽

Chinese Population ◽

Age Groups ◽

Health Screening ◽

Health Examination ◽

Cross Sectional ◽

Fasting Plasma ◽

Percentage Difference ◽

Age And Sex

Abstract Background Fasting plasma glucose (FPG) variability is a significant predictor of mortality, especially in patients with poor glycemic control. This study aimed to explore the temporal age- and sex-specific profiles of temporal FPG variability in a Chinese population undergoing routine health screening and to guide the development of targeted public health interventions for the prevention and control of diabetes. Methods In this cross-sectional study, we used a general linear model to compare differences in temporal FPG values between sexes and across age groups in 101,886 Nanjing residents who underwent a routine physical health examination at the Health Management Center, the First Affiliated Hospital of Nanjing Medical University, in 2018. The variability of FPG as a function of time, age, and sex, independently and in combination, was analyzed. Results The participants included 57,455 (56.4%) males and 44,431 (43.6%) females, with a mean ± SD age of 42.8 ± 15.0 years. The average ± SD FPG level was 5.5 ± 1.1 mmol/L. The monthly variation contributed to 22% of the overall FPG variability. A significant main effect for the age group was observed (F = 7.39, P < 0.05), with an excellent fitting effect (Eta-squared =0.15). The variability of FPG showed sex differences in the percentage difference of the coefficient of variation, which was 34.1% higher in males than females. There were significant interaction effects for month*age*sex and day*age*sex. Conclusions Temporal variability in FPG is evident in the general Chinese population and is affected by both age and sex. To avoid complications associated with FPG variability, interventions should be directed at females and males at specific ages for optimal control of FPG variability and to reduce the risk of diabetes and cardiovascular events.

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Sagittal profile modifications in hybrid versus all screw technique in adolescent idiopathic scoliosis

Scientific Reports ◽

10.1038/s41598-020-79523-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Laura Scaramuzzo ◽

Antonino Zagra ◽

Giuseppe Barone ◽

Stefano Muzzi ◽

Leone Minoia ◽

...

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Cobb Angle ◽

Thoracic Kyphosis ◽

Sagittal Alignment ◽

Vertical Axis ◽

Sagittal Profile ◽

Sacral Slope ◽

Sagittal Vertical Axis ◽

Lenke Classification

AbstractAim of the study was to evaluate sagittal parameters modifications, with particular interest in thoracic kyphosis, in patients affected by adolescent idiopathic scoliosis (AIS) comparing hybrid and all-screws technique. From June 2010 to September 2018, 145 patients were enrolled. Evaluation included: Lenke classification, Risser scale, coronal Cobb angle, thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS). Patients were divided in two groups (1 all-screws and 2 hybrid); a further division, in both groups, was done considering preoperative TK values. Descriptive and inferential statistical analysis was conducted. 99 patients were in group 1, 46 in group 2 (mean follow-up 3.7 years). Patients with a normo-kyphotic profile developed a little variation in TK (Δ pre–post = 2.4° versus − 2.0° respectively). Hyper-kyphotic subgroups had a tendency of restoring a good sagittal alignment. Hypo-kyphotic subgroups, patients treated with all-screw implants developed a higher increase in TK mean Cobb angle (Δ pre–post = 10°) than the hybrid subgroup (Δ pre–post = 5.4°) (p = 0.01). All-screws group showed better results in restoring sagittal alignment in all subgroups compared to hybrid groups, especially in hypo-TK subgroup, with the important advantage to give better correction on coronal plane.

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Lumbar Level Significantly Influences Postoperative Global Sagittal Balance Following Pedicle Subtraction Osteotomy

Global Spine Journal ◽

10.1177/21925682211032563 ◽

2021 ◽

pp. 219256822110325

Author(s):

Athan G. Zavras ◽

T. Barrett Sullivan ◽

Navya Dandu ◽

Howard S. An ◽

Christopher J. DeWald ◽

...

Keyword(s):

Sagittal Balance ◽

Sagittal Alignment ◽

Adult Spinal Deformity ◽

Vertical Axis ◽

Pedicle Subtraction Osteotomy ◽

Current Evidence ◽

Sacral Slope ◽

Sagittal Vertical Axis ◽

Lumbar Level ◽

Global Sagittal Alignment

Study Design: Retrospective cohort study. Objectives: The current evidence regarding how level of lumbar pedicle subtraction osteotomy (PSO) influences correction of sagittal alignment is limited. This study sought to investigate the relationship of lumbar level and segmental angular change (SAC) of PSO with the magnitude of global sagittal alignment correction. Methods: This study retrospectively evaluated 53 consecutive patients with adult spinal deformity who underwent lumbar PSO at a single institution. Radiographs were evaluated to quantify the effect of PSO on lumbar lordosis (LL), thoracic kyphosis (TK), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), T1-spinopelvic inclination (T1SPI), T1-pelvic alignment (TPA), and sagittal vertical axis (SVA). Results: Significant correlations were found between PSO SAC and the postoperative increase in LL ( r = 0.316, P = .021) and PT ( r = 0.352, P = .010), and a decrease in TPA ( r = −0.324, P = .018). PSO level significantly correlated with change in T1SPI ( r = −0.305, P = .026) and SVA ( r = −0.406, P = .002), with more caudal PSO corresponding to a greater correction in sagittal balance. On multivariate analysis, more caudal PSO level independently predicted a greater reduction in T1SPI (β = −3.138, P = .009) and SVA (β = −29.030, P = .001), while larger PSO SAC (β = −0.375, P = .045) and a greater number of fusion levels (β = −1.427, P = .036) predicted a greater reduction in TPA. Conclusion: This study identified a gain of approximately 3 degrees and 3 cm of correction for each level of PSO more caudal to L1. Additionally, a larger PSO SAC predicted greater improvement in TPA. While further investigation of these relationships is warranted, these findings may help guide preoperative PSO level selection.

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Gender-specific analysis for the association between trunk muscle mass and spinal pathologies

Scientific Reports ◽

10.1038/s41598-021-87334-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yusuke Hori ◽

Masatoshi Hoshino ◽

Kazuhide Inage ◽

Masayuki Miyagi ◽

Shinji Takahashi ◽

...

Keyword(s):

Muscle Mass ◽

Bioelectrical Impedance ◽

Vertical Axis ◽

Impedance Analysis ◽

Poor Quality ◽

Trunk Muscle ◽

Sagittal Vertical Axis ◽

Cross Sectional ◽

Lower Trunk ◽

Significant Difference

AbstractWe investigated the relationship between trunk muscle mass and spinal pathologies by gender. This multicenter cross-sectional study included patients aged ≥ 30 years who visited a spinal outpatient clinic. Trunk and appendicular muscle mass were measured using bioelectrical impedance analysis. The Oswestry Disability Index (ODI), visual analog scale (VAS) score for low back pain, sagittal vertical axis (SVA), and EuroQol 5 Dimension (EQ5D) score were investigated to evaluate spinal pathology. The association between trunk muscle mass and these parameters was analyzed by gender using a non-linear regression model adjusted for patients’ demographics. We investigated the association between age and trunk muscle mass. We included 781 men and 957 women. Trunk muscle mass differed significantly between men and women, although it decreased with age after age 70 in both genders. Lower trunk muscle mass was significantly associated with ODI, SVA, and EQ5D score deterioration in both genders; its association with VAS was significant only in men. Most parameters deteriorated when trunk muscle mass was < 26 kg in men and < 19 kg in women. Lower trunk muscle mass was associated with lumbar disability, spinal imbalance, and poor quality of life in both genders, with significant difference in muscle mass.

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