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

Abstract 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.

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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

10.21203/rs.3.rs-599099/v1 ◽

2021 ◽

Author(s):

Xiangyao Sun ◽

Wenzhi Sun ◽

Siyuan Sun ◽

Hailiang Hu ◽

Sitao Zhang ◽

...

Keyword(s):

Logistic Regression ◽

Evaluation System ◽

Statistical Tests ◽

Treatment Strategies ◽

P Value ◽

Global Alignment ◽

Evaluation Systems ◽

Mechanical Complications ◽

Adult Degenerative Scoliosis ◽

Roussouly Classification

Abstract 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.

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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

10.21203/rs.3.rs-576568/v1 ◽

2021 ◽

Author(s):

Xiangyao Sun ◽

Wenzhi Sun ◽

Siyuan Sun ◽

Hailiang Hu ◽

Sitao Zhang ◽

...

Keyword(s):

Logistic Regression ◽

Statistical Tests ◽

Treatment Strategies ◽

Assessment System ◽

P Value ◽

Global Alignment ◽

Evaluation Systems ◽

Mechanical Complications ◽

Adult Degenerative Scoliosis ◽

Roussouly Classification

Abstract 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.

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Does the Global Alignment and Proportion score overestimate mechanical complications after adult spinal deformity correction?

Journal of Neurosurgery Spine ◽

10.3171/2020.6.spine20538 ◽

2021 ◽

Vol 34 (1) ◽

pp. 96-102

Author(s):

Griffin R. Baum ◽

Alex S. Ha ◽

Meghan Cerpa ◽

Scott L. Zuckerman ◽

James D. Lin ◽

...

Keyword(s):

Spinal Deformity ◽

Adult Spinal Deformity ◽

External Validation ◽

Global Alignment ◽

Mechanical Complication ◽

Complication Rates ◽

Mechanical Complications ◽

Significant Difference ◽

Chi Square Analysis

OBJECTIVEThe goal of this study was to validate the Global Alignment and Proportion (GAP) score in a cohort of patients undergoing adult spinal deformity (ASD) surgery. The GAP score is a novel measure that uses sagittal parameters relative to each patient’s lumbosacral anatomy to predict mechanical complications after ASD surgery. External validation is required.METHODSAdult ASD patients undergoing > 4 levels of posterior fusion with a minimum 2-year follow-up were included. Six-week postoperative standing radiographs were used to calculate the GAP score, classified into a spinopelvic state as proportioned (P), moderately disproportioned (MD), or severely disproportioned (SD). A chi-square analysis, receiver operating characteristic curve, and Cochran-Armitage analysis were performed to assess the relationship between the GAP score and mechanical complications.RESULTSSixty-seven patients with a mean age of 52.5 years (range 18–75 years) and a mean follow-up of 2.04 years were included. Patients with < 2 years of follow-up were included only if they had an early mechanical complication. Twenty of 67 patients (29.8%) had a mechanical complication. The spinopelvic state breakdown was as follows: P group, 21/67 (31.3%); MD group, 23/67 (34.3%); and SD group, 23/67 (34.3%). Mechanical complication rates were not significantly different among all groups: P group, 19.0%; MD group, 30.3%; and SD group, 39.1% (χ2 = 1.70, p = 0.19). The rates of mechanical complications between the MD and SD groups (30.4% and 39.1%) were less than those observed in the original GAP study (MD group 36.4%–57.1% and SD group 72.7%–100%). Within the P group, the rates in this study were higher than in the original study (19.0% vs 4.0%, respectively).CONCLUSIONSThe authors found no statistically significant difference in the rate of mechanical complications between the P, MD, and SD groups. The current validation study revealed poor generalizability toward the authors’ patient population.

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Mechanical complications in adult spinal deformity and the effect of restoring the spinal shapes according to the Roussouly classification: a multicentric study

European Spine Journal ◽

10.1007/s00586-019-06253-1 ◽

2019 ◽

Vol 29 (4) ◽

pp. 904-913 ◽

Cited By ~ 9

Author(s):

Amer Sebaaly ◽

Martin Gehrchen ◽

Clément Silvestre ◽

Khalil Kharrat ◽

Tanvir Johanning Bari ◽

...

Keyword(s):

Complication Rate ◽

Adult Spinal Deformity ◽

Spine Deformity ◽

Mechanical Complication ◽

Level Of Evidence ◽

Multicentric Study ◽

Mechanical Complications ◽

Roussouly Classification ◽

Normal Shape

Abstract Purpose To evaluate the incidence of mechanical complications in patients with adult spine deformity (ASD) treated by restoring the normal shape according to the Roussouly classification. Methods This is a retrospective multicentric study with a minimum follow-up of 2 years. Patients operated on with fusion for ASD (minimum performed fusion: L2 to sacrum) were included. Patients with a history of previous spinal fusion of more than three levels were excluded. Spinal and pelvic parameters were measured on the preoperative and the immediate postoperative follow-up. All mechanical complications were recorded. Results A total of 290 patients met the criteria of inclusion with a minimum follow-up of 2 years. Mechanical complications occurred in 30.4% of the cohort. The most common complication was PJK with an incidence of 18% while nonunion or instrumentation failure (rod breakage, implant failure) occurred in 12.4%. 66% of the patients were restored to the normal shape according to the Roussouly classification based on their PI and had a mechanical complication rate of 22.5%, whereas the remaining 34% of patients had a complication rate of 46.8% (p < 0.001). The relative risk for developing a mechanical complication if the algorithm was not met was 3 (CI 1.5–4.3; p < 0.001) Conclusion In the recent literature, there are no clear guidelines for ASD correction. Restoring the sagittal spinal contour to the normal shapes of Roussouly according to the PI could serve as a guideline for ASD treatment. Ignoring this algorithm has a threefold risk of increased mechanical complications. We recommend this algorithm for treatment of ASD. Level of evidence IV cross-sectional observational study. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

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The Adult Degenerative Scoliosis Exercise Trial (Pilot Study)

Case Medical Research ◽

10.31525/ct1-nct03862417 ◽

2019 ◽

Author(s):

Keyword(s):

Pilot Study ◽

Degenerative Scoliosis ◽

Adult Degenerative Scoliosis

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An Unbiased Predictive Model to Detect DNA Methylation Propensity of CpG Islands in the Human Genome

Current Bioinformatics ◽

10.2174/1574893615999200724145835 ◽

2020 ◽

Vol 15 ◽

Author(s):

Dicle Yalcin ◽

Hasan H. Otu

Keyword(s):

Model Building ◽

De Novo ◽

Cpg Islands ◽

Treatment Strategies ◽

Area Under The Curve ◽

Global Methylation ◽

Sequence Features ◽

A Genome ◽

Combined Features ◽

Epigenetic Repression

Background: Epigenetic repression mechanisms play an important role in gene regulation, specifically in cancer development. In many cases, a CpG island’s (CGI) susceptibility or resistance to methylation are shown to be contributed by local DNA sequence features. Objective: To develop unbiased machine learning models–individually and combined for different biological features–that predict the methylation propensity of a CGI. Methods: We developed our model consisting of CGI sequence features on a dataset of 75 sequences (28 prone, 47 resistant) representing a genome-wide methylation structure. We tested our model on two independent datasets that are chromosome (132 sequences) and disease (70 sequences) specific. Results: We provided improvements in prediction accuracy over previous models. Our results indicate that combined features better predict the methylation propensity of a CGI (area under the curve (AUC) ~0.81). Our global methylation classifier performs well on independent datasets reaching an AUC of ~0.82 for the complete model and an AUC of ~0.88 for the model using select sequences that better represent their classes in the training set. We report certain de novo motifs and transcription factor binding site (TFBS) motifs that are consistently better in separating prone and resistant CGIs. Conclusion: Predictive models for the methylation propensity of CGIs lead to a better understanding of disease mechanisms and can be used to classify genes based on their tendency to contain methylation prone CGIs, which may lead to preventative treatment strategies. MATLAB and Python™ scripts used for model building, prediction, and downstream analyses are available at https://github.com/dicleyalcin/methylProp_predictor.

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Second sacral sacralalar‐iliac (S2AI) screw placement in adult degenerative scoliosis (ADS) patients: an imaging study

BMC Surgery ◽

10.1186/s12893-021-01139-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Bing Wu ◽

Kai Song ◽

Junyao Cheng ◽

Pengfei Chi ◽

Zhaohan Wang ◽

...

Keyword(s):

Three Dimensional ◽

Imaging Study ◽

Outer Diameter ◽

Degenerative Scoliosis ◽

Female Patients ◽

Lateral Angle ◽

Adult Degenerative Scoliosis ◽

Imaging Characteristics ◽

Starting Point ◽

Trajectory Length

Abstract Background The imaging characteristics of sacral sacralalar-iliac (S2AI) screw trajectory in adult degenerative scoliosis (ADS) patients will be determined. Methods S2AI screw trajectories were mapped on three-dimensional computed tomography (3DCT) reconstructions of 40 ADS patients. The starting point, placement plane, screw template, and a circle centered at the lowest point of the ilium inner cortex were set on these images. A tangent line from the starting point to the outer diameter of the circle was selected as the axis of the screw trajectory. The related parameters in different populations were analyzed and compared. Results The trajectory length of S2AI screws in ADS patients was 12.00 ± 0.99 cm, the lateral angle was 41.24 ± 3.92°, the caudal angle was 27.73 ± 6.45°, the distance from the axis of the screw trajectory to the iliosciatic notch was 1.05 ± 0.81 cm, the distance from the axis of the screw trajectory to the upper edge of the acetabulum was 1.85 ± 0.33 cm, and the iliac width was 2.12 ± 1.65 cm. Compared with females, the lateral angle of male ADS patients was decreased, but the trajectory length was increased (P < 0.05). Compared to patients without ADS in previous studies, the lateral angle of male patients was larger, the lateral angle of female patients was increased, and the caudal angle was decreased (P < 0.05). Conclusions There is an ideal trajectory of S2AI screws in ADS patients. A different direction should be noticed in the placement of S2AI screws, especially in female patients.

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Validity of the global alignment proportion (GAP) score in predicting mechanical complications after adult spinal deformity surgery in elderly patients

European Spine Journal ◽

10.1007/s00586-021-06734-2 ◽

2021 ◽

Author(s):

Dae-Woong Ham ◽

Ho-Joong Kim ◽

Jae Heouk Choi ◽

Jiwon Park ◽

Junpyo Lee ◽

...

Keyword(s):

Elderly Patients ◽

Spinal Deformity ◽

Adult Spinal Deformity ◽

Global Alignment ◽

Mechanical Complications ◽

Spinal Deformity Surgery ◽

Surgery In Elderly

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Gene expression-based biomarkers designating glioblastomas resistant to multiple treatment strategies

Carcinogenesis ◽

10.1093/carcin/bgab024 ◽

2021 ◽

Author(s):

Otília Menyhárt ◽

János Tibor Fekete ◽

Balázs Győrffy

Keyword(s):

Gene Expression ◽

Treatment Strategies ◽

Area Under The Curve ◽

Predictive Biomarkers ◽

Subsequent Treatment ◽

Survival Status ◽

Multiple Treatment ◽

Post Surgery ◽

Potential Biomarker ◽

Elevated Expression

Abstract Despite advances in molecular characterization of glioblastoma multiforme (GBM), only a handful of predictive biomarkers exist with limited clinical relevance. We aimed to identify differentially expressed genes in tumor samples collected at surgery associated with response to subsequent treatment, including temozolomide (TMZ) and nitrosoureas. Gene expression was collected from multiple independent datasets. Patients were categorized as responders/nonresponders based on their survival status at 16 months post-surgery. For each gene, the expression was compared between responders and nonresponders with a Mann-Whitney U test and receiver operating characteristic. The package "roc" was used to calculate the area under the curve (AUC). The integrated database comprises 454 GBM patients from three independent datasets and 10,103 genes. The highest proportion of responders (68%) were among patients treated with TMZ combined with nitrosoureas, where FCGR2B upregulation provided the strongest predictive value (AUC=0.72, p < 0.001). Elevated expression of CSTA and MRPS17 was associated with a lack of response to multiple treatment strategies. DLL3 upregulation was present in subsequent responders to any treatment combination containing TMZ. Three genes (PLSCR1, MX1, and MDM2) upregulated both in the younger cohort and in patients expressing low MGMT delineate a subset of patients with worse prognosis within a population generally associated with a favorable outcome. The identified transcriptomic changes provide biomarkers of responsiveness, offer avenues for preclinical studies, and may enhance future GBM patient stratifications. The described methodology provides a reliable pipeline for the initial testing of potential biomarker candidates for future validation studies.

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