Assessment of sagittal spinopelvic parameters in a Taiwanese population with spondylolysis by the EOS imaging system: a retrospective radiological analysis

BackgroundAnkylosing spondylitis (AS) patients with kyphosis have an abnormal spinopelvic alignment and pelvic morphology. Most studies focus on the relationship of pelvic tilt (PT) or sacral slope (SS) and deformity, and relatively few studies have addressed the relationship between pelvic incidence (PI) and kyphosis in AS patients. The purpose of this study is to analyze the correlation between pelvic incidence (PI) and the spinopelvic parameters describing local deformity or global sagittal balance in AS patients with thoracolumbar kyphosis.MethodsA total of 94 patients with AS (91 males and 3 females) and 30 controls (27 males and 3 females) were reviewed. The mean age was 36.8 years in AS patients and 34.4 years in controls. Gender ratios and mean age were similar in both group. Sagittal spinopelvic parameters, including PI, PT, SS, thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL), sagittal vertical axis (SVA), the first thoracic vertebra pelvic angle (TPA), spinosacral angle (SSA) and spinopelvic angle (SPA) were measured. The same spine surgeons measured all the parameters of the AS and control group. All the sagittal spinopelvic parameters were compared between the groups. The relationship between PI and other spinopelvic parameters was analyzed with Pearson correlation (r) and unary linear regression model.ResultsAll the sagittal parameters were found to be significantly different between AS patients and controls. Compared with the control group, the AS patients had significantly higher PI(47.4° vs. 43.2°, P < 0.001). Correlation analysis revealed that PI in AS patients was significantly positively correlated with TPA(r = 0.533, R2 = 0.284, P < 0.001), and negatively correlated with SPA(r = − 0.504, R2 = 0.254, P < 0.001). However, no correlations were found between PI and SVA, SSA, TK, TLK or LL in AS patients.ConclusionThis study revealed that increasing PI was significantly correlated with more global sagittal imbalance, not with the local deformity in AS patients with thoracolumbar kyphosis.

Objective To compare the spine-pelvic sagittal parameters of the healthy and young Han males in standing, erect sitting and natural sitting.Evaluate the effect of pelvic rotation on sagittal balance. Methods This was a cross-sectional study. Thirty-two volunteers were recruited from the graduate students of Nanjing Drum Tower Hospital from September 2017 to October 2017. All the volunteers were males, aged between 23 to 27 (24.8±1.6) years old, 171-185 (176.4±5.3) cm in height, 57.7-88.4 (69.5±8.6) kg in weight, and BMI 21.2-24.7 (22.5±2.3) kg/m2. EOS-X-ray imaging system was applied to all subjects, and vertical scanning method was adopted. Full-length images were scanned once, and standing position, erect sitting and natural sitting position were taken. Parameters were measured included thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic incidence (PI), pelvic tilt (PT), sagittal vertical axis (SVA), T1 pelvic angle (TPA). Paired-samples T test was used to compare the changes of parameters in different positions, and Pearson correlation analysis was used to analyze the relationship between spinopelvic parameters. Results For 32 volunteers, in standing position, the average PI was 49.06°±6.22°, PT was 13.38°±6.06°, SS was 35.03°±2.32°, LL was -47.16°±7.64°, TK was 32.22°±9.74°, SVA was (3.29±13.64)mm, TPA was 9.47°±5.26°. In erect sitting position, the average PI was 48.22°±6.07°, PT was 29.06°±10.35°, SS was 18.84°±5.90°, LL was -26.38°±8.45°, TK was 31.78°±9.95°, SVA was (34.73±13.62)mm, TPA was 26.06°±8.71°. In natural sitting position, the average PI was 49.22°±6.20°, PT was 40.50°±10.42°, SS was 9.84°±4.87°, LL was -4.03°±6.14°, TK was 31.69°±9.73°, SVA was (63.37±13.70)mm, TPA was 49.66°±11.22°. Compared with the parameters of standing position, PT, SVA and TPA parameters of erect and natural sitting position increased, SS and LL parameters decreased. Compared with the parameters of erect sitting position: PT, SVA and TPA parameters of natural sitting position increased, SS and LL parameters decreased. The differences were statistically significant(all P values<0.05). Pearson correlation analysis results showed that: (1) In standing position, PI was correlated with PT, LL, TK and TPA. PT was correlated with LL, TK and TPA. LL was correlated with TK and TPA. TK was correlated with TPA. (2) In erect sitting position, PI was correlated with PT, SS, LL, TK and TPA. PT was correlated with SS, LL, TK and TPA. SS was correlated with LL, TK and TPA. LL was correlated with TK and TPA. TK was correlated with TPA. (3) In natural sitting position, PI was correlated with PT, SS, LL, TK and TPA. PT was correlated with SS, LL, TK and TPA. SS was correlated with LL, TK and TPA. LL was correlated with TK and TPA. Differences were statistically significant ( all P values<0.05). Conclusions In the process of from the standing position to the upright sitting position, the upright sitting position to the natural sitting position, Han people the LL of normal Han young men is decreasing and SVA, TPA are increasing.It indicates that SVA moves anteriorly and the pelvic rotates posteriorly. Some correlation between spinal parameters and pelvic parameters are also shown. The changing of pelvis can influence the sagittal alignment and balance of the spine. Key words: Spine; Pelvis; Spinopelvic parameters; Upright sitting; Natural sitting; Pelvic rotation; Sagittal alignment

BackgroundRetrospective analysis of the characteristics and correlation of spino-pelvic sagittal parameters in elderly patients with lumbar degenerative disease.MethodsEighty-seven patients with lumbar degenerative disease, with an average age of 75.4 years old, were enrolled in the observation group. They were all from the orthopedics department of Beijing Hospital and got enrolled in this study from August 2015 to October 2017. Another 80 volunteers, with an average age of 74.5 years old, were enrolled in the control group. Standing lateral radiographs of the full-length spine were taken for all subjects. The following spino-pelvic sagittal parameters were measured: sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT). Statistical analysis was performed to compare the differences of the parameters between groups, and the correlation analysis was also performed.ResultsSVA, PI, and PT of the observation group were significantly higher than those of the control group (p < 0.01), while LL and SS were significantly lower in the observation group (p < 0.01). No significant differences were found in TK between the two groups. The correlation analyses showed that PI was significantly correlated with SS and PT in both the observation group (p < 0.01) and the control group (p < 0.01), so as the SVA-PI (p < 0.05) and SVA-PT (p < 0.01). SS-PT was also significantly correlated in the observation group (p < 0.01) and in the control group (p < 0.05). LL was significantly correlated with all the other parameters in the observation and control groups, including SVA (p < 0.01; p < 0.01), TK (p < 0.01; p < 0.01), PI (p < 0.01; p < 0.01), SS (p < 0.01; p < 0.01), and PT (p < 0.01; p < 0.01). SVA-SS (p < 0.05), TK-PI (p < 0.05), and TK-SS (p < 0.01) were significantly correlated in the control group but not in the observation group.ConclusionReduced coordination of the spine and pelvis in elderly patients with lumbar degenerative disease was observed. Many of the cases were in the state of sagittal imbalance, with the trunk center of gravity moving forward, the integral sagittal alignment becoming straight, and the pelvic posterior tilt increasing. Pelvic parameters were significantly correlated with each other, which may affect the sagittal curve of the spine. LL was a core parameter that significantly correlated with various sagittal parameters.

Introduction Recent studies have focused on spino-pelvic sagittal balance. Changes in sagittal balance could alter the load on the spine and may affect spinal mobility. Increasing recognition of the clinical impacted that sagittal alignment has on back pain and adjacent segment degeneration. But recent studies focused only on the effects of lumbar sagittal alignment to the disk degeneration. The relationship between spino-pelvic sagittal balance and lumbar disk degeneration has yet to be determined. The objective of this research was to study the effect of spino-pelvic sagittal balance on degree of disk degeneration in the lumbar spine. Materials and Methods The lumbar spine magnetic resonance imaging (MRI) and whole spine X-ray of 32 patients (13 males and 19 females) with a mean age of 57.92 years (range: 25 to 84 years) were retrospectively evaluated. Patients with history of prior spinal surgery, serious congenital anomalies, infection, spinal trauma, tumorn or ankylosing spondylitis were excluded from the study. In every patient, spino-pelvic sagittal parameters such as sagittal vertical axis (SVA), thoracic Kyphosis (TK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL), C7 tilt (C7T), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), spino-sacral angle (SSA), spino-pelvic angle (SPA), T1 spiono-pelvic inclination (T1-SPI), and T9 spino-pelvic inclination (T9-SPI) were measured in the whole spine X-ray to evaluate the sagittal balance. And lumbar intervertebral disk degeneration grade for each level (L1/2, L2/3, L3/4, L4/5 and L5/S1) was assessed using the lumbar MRI according to the Pfirrmann grading. The relationship between sagittal parameters and disk degeneration grade was analyzed. Results There was significant correlation between SVA and disk degeneration grade in level L5/S1 ( r = 0.565, p = 0.003) but not significant correlation in level L1/2, L2/3, L3/4 or L4/5. Similarly, significant correlation has been determined between C7T and degree of disk degeneration at the level of L5/S1 ( r = 0.557, p = 0.004), between PT and L2/3 ( r = 0.519, p = 0.008), between SSA and L5/S1 ( r = 0.466, p = 0.019), between SPA and L2/3 ( r = 0.466, p = 0.019), and between T1-SPI and L5/S1 ( r = 0.398, p = 0.049). No significant effect was detected for the degree of disk degeneration with the changes in spino-pelvic parameters like TK, TLK, LL, PI, SS, and T9-SPI. Conclusion Spino-pelvic parameters such as SVA, C7T, SSA, and T1-SPI may have effects on the degeneration of L5/S1 disk. And parameters such as SPA and PT may have effects on the degeneration of L2/3 disk. Changes in spino-pelvic parameters may influence the degree of disk degeneration, but all the parameters are not equally involved in the degree of disk degeneration. I confirm having declared any potential conflict of interest for all authors listed on this abstract No Disclosure of Interest None declared

196. Longitudinal changes of the sagittal plane after posterior spinal fusion of adolescent idiopathic scoliosis in Lenke 5 and 6 from baseline to two-year follow-up

Little data is available on the relationships between sagittal balance and spinopelvic parameters in osteoporosis. We analyzed sagittal spinopelvic parameters in osteoporotic patients. In this prospective study, the patient and control groups comprised 124 osteoporotic patients and 40 controls. Average age was 72.4±6.8 in the osteoporosis group and 42.7±12.5 in the control group, which was significantly different (P<0.001). Osteoporotic patients were allocated to two groups by sagittal vertical axis, namely, a sagittal balance group (n=56) and a sagittal imbalance group (n=68). All 164 study subjects underwent whole spine lateral radiography, which included hip joints. The radiographic parameters investigated were sacral slope, pelvic tilt, pelvic incidence, thoracic kyphosis, lumbar lordosis, and sagittal vertical axis. Statistical analysis was performed to identify significant differences between the two groups. Osteoporotic patients and controls were found to be significantly different in terms of sagittal vertical axis, sacral slope, pelvic tilt, lumbar lordosis, and thoracic kyphosis. However, no significant difference was observed between patients and controls in terms of pelvic incidence (P>0.05). Significant differences were found between the balance and imbalance groups in terms of age, lumbar spine bone mineral density (LSBMD), femoral neck BMD (FNBMD), visual analogue scale (VAS) score, sacral slope, and pelvic incidence. Correlation analysis revealed significant relationships between sagittal parameters and osteoporosis. Stepwise logistic regression analysis revealed that FNBMD and pelvic incidence contributed significantly to sagittal balance. Sagittal spinopelvic parameters were found to be significantly different in patients and normal controls. Significant relationships were found between sagittal spinopelvic parameters in osteoporotic patients. In particular, low FNBMD and high pelvic incidence were significant parameters in determination of sagittal balance in osteoporotic patients.

ObjectiveThis study aims to investigate the correlation between spinopelvic parameters in supine position (pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL)), disc degeneration and herniation of the thoracolumbar spine, as well as cardiovascular risk factors and back pain in a southern German cohort from the general population.MethodsThis study is a cross-sectional, case–control study drawn from a prospective cohort of the “Cooperative Health Research in the Region of Augsburg/Kooperative Gesundheitsforschung in der Region Augsburg” study (KORA). In total, 374 participants (mean age 56.4 ± 9.2 years; 57.8% male) from the whole-body MRI cohort (FF4) were included. All participants underwent a standardized whole-body MRI on which disc degeneration of the thoracic and lumbar spine was evaluated using a sequence adapted Pfirrmann score. PI, PT, SS and LL were measured according to the description in the literature, using sagittal imaging. Furthermore, disc bulging and protrusion were assessed. Correlations were estimated by logistic regression models providing odds ratios.ResultsMean PI was 54.0° ± 11.1°, PT 13.0° ± 5.8°, SS 40.2° ± 8.8° and LL 36.2° ± 9.6°. SS was greater in men (p<0.05) and lumbar lordosis in women (p<0.001). PT increased by 0.09° per age-year with rising age. Age was not associated with PI, SS and LL. Neither BMI, hypertension, cholesterol, lipid levels, nor physical activity were associated with PI, PT, SS or LL. Diabetes mellitus negatively correlated with SS (β = -4.19; 95%CI -7.31–1.06, p<0.01). Smaller spinopelvic parameters (PI, SS and LL) where significantly (p<0.05) correlated with an increased frequency of disc bulging, as well as a local clustering in the lumbar, but not the thoracic spine.ConclusionIn conclusion, spinopelvic parameters, measured in supine position, are significantly correlated with disc bulging alone; there is no significant correlation between supine spinopelvic parameters and disc degeneration, back pain or cardiovascular risk factors.

Introduction The anatomical relationship between elements of the spinopelvic linear chain does not appear to be uniform across different ethnic and population groups, based on measurements of radiographic parameters presented in the literature in populations with different origins. These studies have demonstrated variability in spinal and pelvic parameters among the groups studied, which makes it important to know their normative values, specific for a population. Such knowledge enables surgeons to individualize treatment goals for deformities in a specific adult population. The aim of this study was to present normal values of sagittal spinal and spinopelvic parameters in a Brazilian population sample and analyze the effect of age on these parameters. Materials and Methods This is a prospective observational study involving asymptomatic volunteers in a Brazilian population sample. The volunteers that accepted to participate had obtained total spine radiography in addition to collecting demographic data, including age and sex. The radiographic parameters evaluated were: Sagittal vertical axis (EVS), T1-spinopelvic inclination (T1-SPI), pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), and thoracic kyphosis (TK). We also consider the mismatch between the PI and the LL (PI-LL). These radiographic parameters were compared between the age groups of volunteers, divided into three groups: 18 to 39, 40 to 59, and older than 60 years. Results In total, 167 asymptomatic volunteers were enrolled, 105 women and 62 men with a mean age of 45.8 years (range, 18–74). In regards to the age group, 54 volunteers had 18 to 39, 79 had 40 to 59, and 34 had older than 60 years of age. The mean values of radiographic parameters in the total sample were: SVA −11.77 mm, T1-SPI- 5.47 degrees, IP: 46.93 degrees, PT: 13.77 degrees, SS: 33.05 degrees, LL: 54.53 degrees, PI-LL: −6.98 degrees, and TK: 40.54 degrees. Comparing the values regarding age, it was observed that higher the age of individuals is, occurs a statistically significant increase in the values of SVA, PT, T1-SPI, and PI-LL ( p &lt; 0.001, &lt; 0.001, 0.001, and 0.004, respectively). Conclusion The study presented normal values of sagittal spine and spinopelvic parameters in a sample of a Brazilian population, and also showed that there is an increase in anterior tilt of the trunk and a larger pelvic retroversion directly proportional to the increase in age of the individuals.

Prospective study. To analyze sagittal spinopelvic parameters in ankylosing spondylitis (AS) patients. There are little data on the relationship between the sagittal spinopelvic parameters and AS. The study and control groups comprised 90 AS patients and 40 controls. Participants were classified into 3 groups: normal (n=40), sagittal balance (n=58), and sagittal imbalance (n=32) groups. All underwent lateral radiograph of the whole spine including hip joints. The radiographic parameters were sacral slope, pelvic tilting, pelvic incidence, overhang of S1, thoracic kyphosis, lumbar lordosis, and C7 plumbline. Statistical analysis was performed to identify significant differences between the 2 groups. Correlations between radiological parameters and symptoms were sought. AS patients and controls were found to be significantly different in terms of sagittal balance, sacral slope, pelvic tilt, pelvic incidence, S1 overhang, and lumbar lordosis. However, no significant difference was observed between these 2 groups for thoracic kyphosis (P>0.05). Of the 90 AS patients, 32 patients (5 women and 27 men) were assigned to the sagittal imbalance group and 58 (12 women and 46 men) to the sagittal balance group. There was a significant difference in all sagittal parameters and visual analogue scale (VAS) score between these 2 groups. Correlation analysis revealed significant relationships between sagittal parameters in AS. However, there was no association between sacral slope and S1 overhang, and between pelvic incidence and VAS score. Stepwise logistic regression analysis revealed that pelvic tilt contributed significantly to sagittal balance. AS patients and normal controls were found to be significantly different in terms of sagittal spinopelvic parameters. Significant relationships were found between sagittal spinopelvic parameters in AS patients. Pelvic tilt was a significant parameter in determination of sagittal balance in AS patient. Furthermore, VAS scores were significantly related to sagittal spinal parameters which were closely related with pelvic orientation in AS patients.

Objective To explore the correlation between pelvic incidence(PI) and the sagittal spinopelvic balance in degenerative lumbar scoliosis (DLS). Methods From Jan 2008 to Dec 2014, 136 cases of DLS were enrolled as experimental group, 120 healthy age-and gender-matched adults were enrolled as control group. All the participants were divided into three goups according to the PI value: low (PI less than 45° ), middle (PI between 45° and 60° ), and high PI group (PI more than 60° ). Sagittal balance was determined by measuring the sagittal vertical axis (SVA), thoracic kyphosis (TK), thoracolumbar junction (TLJ), lumbar lordosis (LL), PI, sacral slope (SS), pelvic tilt (PT) were measured at a full spine lateral radiograph, sagittal spinopelvic parametersr were compared between the DLS patients and asymptomatic adults in each PI group. The correlations between spinopelvic parameters were determined using the Pearson correlation coefficient. Results The number of DLS patients with low, middle, and high PI were 38 (27.9%), 50 (36.8%), and 48 (35.3%), respectively. In the Control group, the number of low, middle, and high PI patients were 52 (43.3%), 41 (34.2%), and 27 (22.5%), respectively. In the Experimental group, patients with high PI always presented with large LL, PT, SS and smaller SVA(all P values 0.05) and the PT was large in high PI than that in middle PI(P<0.01). In the control group and DLS group, PI determined pelvic orientation(PT, SS) and sagittal spinal patameters(LL, TLJ). In terms of correlation between SS and LL, between SS and TLJ, both DLS and control groups showed significant correlations(all P values<0.05). In terms of correlation between PT and SVA, only the DLS group showed a significant correlation(P<0.05). Compared with the asymptomatic adults, DLS patients showed a high PT and low SS as well as lumbar hypolordosis, thoracic hypokyphosis and decreased TLJ in all PI groups(all P values<0.01). Conclusions The compensatory mechanisms of the spine and pelvis in DLS patients depend on PI, the increased PT in high PI and the increased SS in low PI are often observed respectively, surgical planning and lumbar curve restoration should be also dependent on the value of PI. Key words: Scoliosis; Intervertebral disc degeneration; Radiography; Pelvis; Pelvic incidence

A retrospective radiographic study. The aim of this study is to demonstrate that lumbar retrolisthesis serves as an important compensatory mechanism and to identify the possible factor related to lumbar retrolisthesis. Lumbar instability is one of the common degenerative changes, which presents as 2 radiologic features: anterolisthesis and retrolisthesis. Compared with the extensive studies on anterolisthesis, limit data are available on the characteristics and clinical relevance of lumbar retrolisthesis. In this study, 105 adult patients with low back pain were prospectively recruited, of which 60 patients had retrolisthesis (group 1) and 45 patients had anterolisthesis (group 2). Another 40 healthy age-matched adults (group 3) were also included to serve as the control group. Sagittal spinopelvic parameters were measured from the standing lateral radiograph, including thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL), pelvic incidence (PI), sacrum slope (SS), pelvic tilt (PT), sagittal vertical axis (SVA), spinosacral angle (SSA), and C7 tilt (C7T). In addition, disk degeneration was quantitatively evaluated by Pfirrmann score on T2-weighted magnetic resonance images in patients with retrolisthesis. For all the sagittal parameters, SVA, PI, SS, and LL in retrolisthesis group were found to be significantly lower than those in the anterolisthesis group and in the control group, respectively (P<0.05), whereas TLK in retrolisthesis group was significantly larger than other 2 groups (P<0.01). In addition, the average Pfirrmann disk score was 2.11 at levels with retrolisthesis indicating that the disks were not severely degenerated. Lumbar retrolisthesis, together with thoracolumbar kyphosis, appears to be associated with mechanisms associated with regulation of sagittal balance. Low PI and disk instability due to degeneration may contribute to the development and progression of retrolisthesis.

Normal spino-pelvic parameters and correlation between lumbar lordosis (LL) and pelvic incidence (PI) in children and adolescents in Indian population.

The correlation between sagittal spinopelvic alignment and degree of lumbar degenerative spondylolisthesis

Few studies have concentrated on the sagittal alignment of lumbar disc herniation (LDH), especially the parameters of the pelvis, and controversy exists about whether pelvic morphology is involved in the pathogenesis of LDH. The present study analyzed the characteristics of the sagittal alignment in young Chinese LDH patients and explored the impact of pelvic morphology on the pathogenesis of LDH. A retrospective analysis was conducted on 100 young patients with LDH (69 men and 31 women, aged 18-35 years), and the clinical and imaging findings met the criteria for the diagnosis of LDH. The control group included 100 asymptomatic volunteers with matching age and gender. Coronal and sagittal parameters were measured on the anteroposterior and lateral radiographs of the whole spine, including lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), thoracic kyphosis (TK), and sagittal balance (SVA). The cases were classified into four types by the apex position of lumbar lordosis (type I, L5 or the L4-5 intervertebral space; type II, bottom or middle of L4 ; type III, upper part of L4 or the intervertebral space between L3 and L4 ; type IV, L3 or more high level), and divided into three groups by PI; namely, a low PI group (PI < 40°), a medium PI group (40° ≤ PI < 50°), and a high PI group (PI ≥ 50°). The sagittal parameters, especially PI, were compared between the LDH group and the control group. Correlations between the parameters in the LDH group were analyzed. The PI value of the LDH group was not different from that of the control group (46.1° ± 10.0° vs 47.2° ± 8.8°, P > 0.05). The LDH group showed lower average LL, SS, and TK (P < 0.01), as well as higher PT and SVA compared with the control group (P < 0.01). The LL (34.4° ± 15.3° vs 50.8° ± 10.2°) and SVA (21.6 ± 53.6 mm vs - 18.4 ± 32.8 mm) showed a significant difference (P < 0.01); LL was correlated with PI, SS, PT, TK and SVA (P < 0.01); and SVA was also correlated with the parameters above (P < 0.01) except PI (P > 0.05), and the lordosis apex tended to be higher. The distributions of PI groups between the LDH group and the control group were not different. Pairwise correlations were found among LL, PI, SS, and PT. In addition, TK and SVA were correlated with LL, SS, and PT. There is no difference in PI between young Chinese patients with lumbar disc herniation and the normal population. Young LDH patients may present flat lumbar and thoracic curves, as well as lower sacral slope. The anteversion sagittal imbalance is regulated by both the spine and the pelvis.

Radiological analysis of lumbar degenerative kyphosis in relation to pelvic incidence