Which sagittal evaluation system can effectively predict mechanical complications in the treatment of elderly patients with adult degenerative scoliosis? Roussouly classification or Global Alignment and Proportion (GAP) Score

Background To achieve the proper sagittal alignment, previous studies have developed different assessment systems for adult degenerative scoliosis (ADS) which could help the spine surgeon in making treatment strategies. The purpose of our study is to evaluate whether Roussouly classification or global alignment and proportion (GAP) score is more appropriate in the prediction of mechanical complications after surgical treatment of ADS. Methods ADS patients who received long segmental fusion in the treatment during the period from December 2016 to December 2018 were evaluated in this study. Basic information and radiologic measurements were collected for analysis. Patients were divided into two groups according to occurrence or absence of mechanical complications for comparison. Mechanical complications included proximal junctional kyphosis (PJK), proximal junctional failure (PJF). GAP categories divided GAP score into proportioned spinopelvic position, moderately disproportioned position, and severely disproportioned position according to the cut-off values. The correlation between evaluation systems and mechanical complications was analyzed through a logistic regression model via stepwise backward elimination based on the Wald statistics. Receiver operator characteristic (ROC) curve was used to determine the predictability of the evaluation systems in the occurrence of mechanical complications and calculate their cut-off value. Area under the curve (AUC) was used to evaluate the validity of the thresholds. Results A total of 80 patients were included in this study. There were 41 patients in mechanical complication group and 39 patients in no mechanical complication group. GAP score (P = 0.008) and GAP categories (P = 0.007) were positively correlated with mechanical complications; Roussouly score was negatively correlated with mechanical complications (P = 0.034); GAP score was positively correlated with PJK (P = 0.021); Roussouly score was negatively correlated with implant-related complications (P = 0.018); GAP categories were correlated with implant loosening (P = 0.023). Results of ROC showed that GAP score was more effective in predicting PJK (AUC = 0.863) and PJF (AUC = 0.724) than Roussouly score; GAP categories (AUC = 0.561) was more effective than GAP score (AUC = 0.555) in predicting implant-related complications. Conclusions Roussouly classification could only be a rough estimate of optimal spinopelvic alignment. Quantitative parameters in GAP score made it more effective in predicting mechanical complications, PJK and PJF than Roussouly classification.

Does the sagittal spinal profile differ between the elderly Chinese populations with and without lumbar disc herniation?

Background The influence of spinopelvic morphology on the Chinese elderly LDH population was not clear. The purpose of this study is to explore its influence on the characteristics of lumbar disc herniation or degeneration. Methods 212 elderly patients with LDH and 213 asymptomatic volunteers were involved. Spinal parameters were measured on full-length X-ray and compared between two populations. In herniated group, sagittal profiles were determined according to the Roussouly classification, the degenerative grades, the herniated location and the number of intervertebral lumbar disc degeneration were evaluated from the L1 to S1 on MRI scans. The differences on them among Roussouly types were analyzed. Results There were no significant differences in BMI, the mean value of age and sex distribution between two populations. Patients were found to have significantly smaller TK, LL, and SS than those volunteers (p < 0.05), while contradicting observations on PT and TPA were obtained (p < 0.05). Roussouly type 1 and type 2 ( 50.4% and 28.7% respectively) are predominant in the LDH population and the proportion of type 1 in elderly LDH is further increased. Subjects with LDH in type 1 and 2 had lower mean herniated locations and fewer mean herniated numbers than those with type 3 and 4. Conclusions Sagittal spinopelvic parameters were found to be significantly different in elderly LDH patients and asymptomatic volunteers. There were significant differences in the Roussouly distribution among different age groups of LDH. Different Roussouly subtypes have different effects on lumbar disc degeneration and herniation.

Which Sagittal Evaluation System Can Effectively Predict Mechanical Complications in the Treatment of Elderly Patients With Adult Degenerative Scoliosis? Roussouly Classification or Global Alignment and Proportion (GAP) Score

Background: To achieve the proper sagittal alignment, previous studies have developed different assessment systems for degenerative spinal deformity which could help us in making treatment strategies. The purpose of our study is to evaluate whether Roussouly classification or GAP score is more appropriate in the prediction of mechanical complications after surgical treatment of ADS.Methods: The ADS patients who received long segmental fusion in the treatment during the period from December 2016 to December 2018 were evaluated in this study. The basic information of the patients and all radiologic measurements, which were included in GAP score and Roussouly classification, were collected for analysis. Patients were divided into two groups according to occurrence or absence of mechanical complications for comparison. The correlation between evaluation systems and mechanical complications could be analyzed in logistic regression model via stepwise backward elimination based on the Wald statistics. ROC curve was used to determine the predictability of the evaluation systems in the occurrence of mechanical complications and calculate their cut-off value. A two-tailed P value < 0.05 was statistically significant for all statistical tests.Results: A total of 80 cases were included in this study. The results of logistic regression showed: GAP score (P = 0.008) and GAP categories (P = 0.007) were positively correlated with mechanical complications; Roussouly score was negatively correlated with mechanical complications (P=0.034); GAP score was positively correlated with PJK (P = 0.021); Roussouly score was negatively correlated with implant-related complications (P = 0.018); GAP categories were correlated with implant loosening (P = 0.023). Results of ROC showed that GAP score was most effective in predicting PJK (AUC = 0.863) and PJF (AUC = 0.724); GAP categories (AUC = 0.561) was more effective than GAP score (AUC = 0.555) in predicting implant-related complications.Conclusions: Roussouly-type matching could not accurately predict the risk of mechanical complications. In contrast, GAP score was most effective in predicting PJK and PJF. The GAP score was better than Roussouly classification in predicting mechanical complications.

Which Sagittal Assessment System Can Effectively Predict the Risk of Mechanical Complications in the Treatment of Elderly Patients With Adult Degenerative Scoliosis? Roussouly Classification or Global Alignment and Proportion (GAP) Score

Background: In order to achieve the proper sagittal alignment, previous studies have developed different assessment systems for degenerative spinal deformity which could help us in making treatment strategies. The purpose of our study is to evaluate whether Roussouly classification or GAP score is more appropriate in the prediction of mechanical complications in the treatment of ADS.Methods: The ADS patients who received long segmental fusion in the treatment during the period from December 2016 to December 2018 were evaluated in this study. The basic information of the patients and all radiologic measurements, which were included in GAP score and Roussouly classification, were collected for analysis. Patients were divided into two groups according to occurrence or absence of mechanical complications for comparison. The correlation between evaluation systems and mechanical complications could be analyzed in logistic regression model via stepwise backward elimination based on the Wald statistics. ROC curve was used to determine the predictability of the evaluation systems in the occurrence of mechanical complications and calculate their cut-off value. A two-tailed P value < 0.05 was statistically significant for all statistical tests.Results: A total of 80 cases were included in this study. The results of logistic regression showed: GAP score (P = 0.008) and GAP categories (P = 0.007) were positively correlated with Mechanical complications; Roussouly score was negatively correlated with mechanical complications (P=0.034); GAP score was positively correlated with PJK (P = 0.021); Roussouly score was negatively correlated with implant-related complications (P = 0.018); GAP categories were correlated with implant loosening (P = 0.023). Results of ROC showed that GAP score was mostly effective in predicting PJK (AUC = 0.863) and PJF (AUC = 0.724); GAP categories (AUC = 0.561) was more effective than GAP score (AUC = 0.555) in predicting implant-related complications.Conclusions: Roussouly-type matching could not accurately predict the risk of mechanical complications. In contrast, GAP score was mostly effective in predicting PJK and PJF. The GAP score was better than Roussouly classification in predicting mechanical complications.

CORRELATION BETWEEN DEGENERATIVE DISEASES OF THE LUMBAR SPINE AND TYPES OF LUMBAR LORDOSIS

ABSTRACT Objective: Evaluate the relationship between the incidence of different types of degenerative diseases of the spine and lumbopelvic biomechanics, according to the types of lordosis of Roussouly's classification. Methods: Retrospective study of medical records and results of imaging exams of patients seen at a private hospital in São Paulo. The sagittal alignment of these patients was evaluated by classifying them according to Roussouly into 4 types, based on panoramic radiographs of the spine. These results were correlated with the patient's degenerative diagnosis (Herniated disc, Canal stenosis, Spondylolisthesis, degenerative discopathy and Facet arthrosis). Statistical tests were performed comparing the types of curvature and diagnoses identified. Results: 418 patients were evaluated, 51.4% male and 49.6% female. The vast majority of patients, about 54%, had a diagnosis of herniated lumbar disc. There was a statistically significant difference that showed a predilection for surgical treatment in cases classified as Type I and Type II in the Roussouly classification. There was no statistically significant difference that correlated the types of lumbar lordosis with the diagnosis presented by the patients. Conclusion: There is no statistically significant difference that correlates the type of lumbar lordosis according to Roussouly with lumbar degenerative diseases. In contrast, patients classified as Type 1 and Type 2 by Roussouly underwent a greater number of surgical treatments compared to patients type 3 and 4, with statistical relevance. Level of evidence 2; Retrospective prognostic study.

Variations of Sagittal Alignment in Standing Versus Sitting Positions Under the Roussouly Classification in Asymptomatic Subjects

Study Design: Prospective radiological analysis. Objective: To investigate the characteristics of the sagittal spinopelvic alignment in the standing and sitting positions under the Roussouly classification in a healthy population. Methods: This study using standing and sitting lateral radiographs included 143 volunteers whose spinopelvic parameters were measured. The parameters were compared in the standing and sitting positions. The lumbo-pelvic profile was identified according to the Roussouly classification. The differences in the values of the parameters between the standing and sitting positions were analyzed. The different frequencies of the unchanged apex were assessed. Results: All parameter values except the thoracolumbar angle (TLK) were significantly altered. With regard to the classification of the lumbopelvic profile, 15 (10.5%) subjects were excluded because they were evaluated as not belonging to any of the Roussouly types. The remaining 128 subjects were evaluated and classified as follows: 19 (14.8%), type 1; 53 (41.4%), type 2; 9 (7.0%), type 3 + anteverted pelvis (AP); 33 (25.8%), type 3; and 14 (10.9%), type 4. The differences in the pelvic tilt (PT), sacral slope (SS), and thoracic pelvic angle (TPA) values were significantly lower in types 1 and 2 than in other Roussouly types. Corresponding variations in the apical vertebra for the sagittal lumbar curves in the sitting position were observed. Conclusions: Subjects with Roussouly type 1 and type 2 sagittal alignments were found to be less capable of performing changes in alignment when changing to the sitting position. The characteristics of the apical movement were also different.

Straighter low lumbar curvature in isthmic spondylolisthesis at L4

Background: This study was conducted to compare differences in imaging features and clinical symptoms between patients with single-level isthmic spondylolisthesis (IS) at L4 and at L5 and to investigate the correlation between imaging and clinical parameters. Methods: This cross-sectional study evaluated patients with single-level IS who were enrolled between June 2011 and June 2018. A total of 139 patients, 44 in the L4 IS group and 95 in the L5 IS group, met the study criteria and were included. Imaging and clinical parameters obtained from the two groups were compared and analyzed.Results: Patients in the L4 IS group had smaller lower lumbar lordosis (LLL) (27.1 ± 8.2 vs. 30.9 ± 9.3, P = 0.021) and were of older age (58.5 ± 8.7 vs. 52.8 ± 10.1, P < 0.01) than those in the L5 IS group. As per the Roussouly classification system, most patients with L4 IS were classified as Type 2 (43.2%), whereas most patients with L5 IS fell under Type 3 (44.2%). In the L5 IS group, pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), and L5 incidence (L5I) were positively associated with slippage rate (SR), but the lumbosacral angle (LSA) was negatively associated with SR (P < 0.01). In the L4 IS group, only L5I showed a positive association with SR (P < 0.01). More significant associations were found among sagittal lumbo-pelvic parameters in the L5 IS group, but none were found between SR and Oswestry Disability Index (ODI) in either group.Conclusions: When compared with patients with L5 IS, patients with L4 IS were of older age and had straighter low lumbar curvature when they were obviously symptomatic. PI was an important parameter for patients with L5 IS while for those with L4 IS, L5I deserved more attention for its significantly positive correlation with the degree of slippage.

SPINOPELVIC VARIABILITY ACCORDING TO THE ROUSSOULY CLASSIFICATON CURVE TYPE

ABSTRACT Objective To evaluate the variability of spinopelvic sagittal parameters and the distribution of lordosis in the lumbar spine in a sample of patients. Methods This is a cross-sectional study considering full-spine radiographs of a patient sample. The patients were classified according to the Roussouly classification and both radiographic spinopelvic alignment parameters and the lordosis measurement of each lumbar spinal segment were considered. The radiographic parameters were correlated with the Roussouly classification type. Results Ninety patients were included in the study. There was significant correlation between pelvic incidence (PI) and lumbar lordosis (LL) (R=0.89; p<0.0001). The values of PI were significantly higher in Roussouly types 3 and 4 than in types 1 and 2 (p<0.001), as were the values of LL L1-S1(p<0.001). Considering the total sample, 67% of LL L1-S1 was located between L4-S1, but with variations by the Roussouly classification curve types. Conclusion This study demonstrated a high correlation between the values of PI and LL, as well as the importance of the distal lumbar segment (L4-S1) in the overall value of LL L1-S1, which was even higher in patients with a lower PI value (Roussouly types 1 and 2). Level of evidence II; Retrospective analysis of a prospective database (Cohort); Diagnostic study.