Study Design: Retrospective cohort study. Objective: To develop parameter thresholds obtainable from cervical radiographs that correlate with concomitant thoracolumbar malalignment. Summary of Background Data: T1 slope (T1S) is typically discussed in the context of cervical deformity and correlated with health-related quality of life outcomes. Prior research suggests that T1S is related to global alignment; however, a definition for “high” T1S has not been established. Most patients undergoing cervical surgery do not undergo full-spine imaging; therefore, obtaining a parameter associated with thoracolumbar malalignment from cervical radiographs would be beneficial. Methods: A database of preoperative adult spinal deformity (ASD) patients was analyzed. Measures obtained from standing lateral radiographs included T1S, thoracic kyphosis (TK), sagittal vertical axis (SVA), T1-pelvic angle (TPA), pelvic tilt (PT), and pelvic incidence minus lumbar lordosis (PI-LL). Decision tree analysis was then used to determine the T1S corresponding to published thresholds for high TK (40 degrees), SVA (40 mm), TPA (25 degrees), and PT (25 degrees). Alignment between high and normal T1S patients was compared. Results: Two hundred twenty-six preoperative patients were included (mean: 58±16 y 62%F). Larger T1S was correlated with greater SVA (r=0.365), TPA (r=0.302), TK (r=0.606), and PT (r=0.230) (all P<0.001). Decision tree analysis yielded a threshold of 30 degrees for high T1S, which 50% of patients had. Compared with patients with T1S <30 degrees, those with T1S >30 degrees had higher TK (41.5 vs. 25.8 degrees), SVA (78.7 vs. 33.7 mm), TPA (27.6 vs. 18.3 degrees), and PT (26.3 vs. 20.8 degrees), and PI-LL (18.2 vs. 11.7 degrees) (all P<0.05). Seventy-nine percent of patients with high T1S had high TK (T1S <30=13%), 69% had high SVA (T1S <30=38%), 66% had high TPA (T1S <30=37%), 60% had PT >25 degrees (T1S <30=42%), and 47% had PI-LL >20 degrees (T1S <30=34%) (all P<0.05). Conclusion: Higher T1S was associated with worse global alignment. T1S was most strongly associated with TK. A T1S=30 degrees corresponded to high TK, SVA, TPA, and PT thresholds. Therefore, surgeons should consider obtaining full-spine radiographs if a T1S >30 degrees is present on cervical imaging.

Study Design/Setting. Retrospective single-center study. Background. The global alignment and proportion score is widely used in adult spinal deformity surgery. However, it is not specific to the parameters used in adult cervical deformity (ACD). Purpose. Create a cervicothoracic alignment and proportion (CAP) score in patients with operative ACD. Methods. Patients with ACD with 2-year data were included. Parameters consisted of relative McGregor’s Slope [RMGS = (MGS × 1.5)/0.9], relative cervical lordosis [RCL = CL – thoracic kyphosis (TK)], Cervical Lordosis Distribution Index (CLDI = C2 – Apex × 100/C2 – T2), relative pelvic version (RPV = sacral slope – pelvic incidence × 0.59 + 9), and a frailty factor (greater than 0.33). Cutoff points were chosen where the cross-tabulation of parameter subgroups reached a maximal rate of meeting the Optimal Outcome. The optimal outcome was defined as meeting Good Clinical Outcome criteria without the occurrence of distal junctional failure (DJF) or reoperation. CAP was scored between 0 and 13 and categorized accordingly: ≤3 (proportioned), 4–6 (moderately disproportioned), >6 (severely disproportioned). Multivariable logistic regression analysis determined the relationship between CAP categories, overall score, and development of distal junctional kyphosis (DJK), DJF, reoperation, and Optimal Outcome by 2 years. Results. One hundred five patients with operative ACD were included. Assessment of the 3-month CAP score found a mean of 5.2/13 possible points. 22.7% of patients were proportioned, 49.5% moderately disproportioned, and 27.8% severely disproportioned. DJK occurred in 34.5% and DJF in 8.7%, 20.0% underwent reoperation, and 55.7% achieved Optimal Outcome. Patients severely disproportioned in CAP had higher odds of DJK [OR: 6.0 (2.1–17.7); P =0.001], DJF [OR: 9.7 (1.8–51.8); P =0.008], reoperation [OR: 3.3 (1.9–10.6); P =0.011], and lower odds of meeting the optimal outcome [OR: 0.3 (0.1–0.7); P =0.007] by 2 years, while proportioned patients suffered zero occurrences of DJK or DJF. Conclusion. The regional alignment and proportion score is a method of analyzing the cervical spine relative to global alignment and demonstrates the importance of maintaining horizontal gaze, while also matching overall cervical and thoracolumbar alignment to limit complications and maximize clinical improvement.

BACKGROUND AND OBJECTIVES:For patients with surgical adult spinal deformity (ASD), our understanding of alignment has evolved, especially in the last 20 years. Determination of optimal restoration of alignment and spinal shape has been increasingly studied, yet the assessment of how these alignment schematics have incrementally added benefit to outcomes remains to be evaluated. METHODS:Patients with ASD with baseline and 2-year were included, classified by 4 alignment measures: Scoliosis Research Society (SRS)-Schwab, Age-Adjusted, Roussouly, and Global Alignment and Proportion (GAP). The incremental benefits of alignment schemas were assessed in chronological order as our understanding of optimal alignment progressed. Alignment was considered improved from baseline based on SRS-Schwab 0 or decrease in severity, Age-Adjusted ideal match, Roussouly current (based on sacral slope) matching theoretical (pelvic incidence-based), and decrease in proportion. Patients separated into 4 first improving in SRS-Schwab at 2-year, second Schwab improvement and matching Age-Adjusted, third two prior with Roussouly, and fourth improvement in all four. Comparison was accomplished with means comparison tests and χ 2 analyses. RESULTS:Sevenhundredthirty-two. patients met inclusion. SRS-Schwab BL: pelvic incidence-lumbar lordosis mismatch (++:32.9%), sagittal vertical axis (++: 23%), pelvic tilt (++:24.6%). 640 (87.4%) met criteria for first, 517 (70.6%) second, 176 (24%) third, and 55 (7.5%) fourth. The addition of Roussouly (third) resulted in lower rates of mechanical complications and proximal junctional kyphosis (48.3%) and higher rates of meeting minimal clinically important difference (MCID) for physical component summary and SRS-Mental ( P < .05) compared with the second. Fourth compared with the third had higher rates of MCID for ODI (44.2% vs third: 28.3%, P = .011) and SRS-Appearance (70.6% vs 44.8%, P < .001). Mechanical complications and proximal junctional kyphosis were lower with the addition of Roussouly ( P = .024), while the addition of GAP had higher rates of meeting MCID for SRS-22 Appearance ( P = .002) and Oswestry Disability Index ( P = .085). CONCLUSION:Our evaluation of the incremental benefit that alignment schemas have provided in ASD corrective surgery suggests that the addition of Roussouly provided the greatest reduction in mechanical complications, while the incorporation of GAP provided the most significant improvement in patient-reported outcomes.

STUDY DESIGN/SETTING:This was a retrospective cohort study.BACKGROUND:Little is known of the intersection between surgical invasiveness, cervical deformity (CD) severity, and frailty.OBJECTIVE:The aim of this study was to investigate the outcomes of CD surgery by invasiveness, frailty status, and baseline magnitude of deformity.METHODS:This study included CD patients with 1-year follow-up. Patients stratified in high deformity if severe in the following criteria: T1 slope minus cervical lordosis, McGregor's slope, C2-C7, C2-T3, and C2 slope. Frailty scores categorized patients into not frail and frail. Patients are categorized by frailty and deformity (not frail/low deformity; not frail/high deformity; frail/low deformity; frail/high deformity). Logistic regression assessed increasing invasiveness and outcomes [distal junctional failure (DJF), reoperation]. Within frailty/deformity groups, decision tree analysis assessed thresholds for an invasiveness cutoff above which experiencing a reoperation, DJF or not achieving Good Clinical Outcome was more likely.RESULTS:A total of 115 patients were included. Frailty/deformity groups: 27% not frail/low deformity, 27% not frail/high deformity, 23.5% frail/low deformity, and 22.5% frail/high deformity. Logistic regression analysis found increasing invasiveness and occurrence of DJF [odds ratio (OR): 1.03, 95% CI: 1.01-1.05, P =0.002], and invasiveness increased with deformity severity ( P <0.05). Not frail/low deformity patients more often met Optimal Outcome with an invasiveness index <63 (OR: 27.2, 95% CI: 2.7-272.8, P =0.005). An invasiveness index <54 for the frail/low deformity group led to a higher likelihood of meeting the Optimal Outcome (OR: 9.6, 95% CI: 1.5-62.2, P =0.018). For the frail/high deformity group, patients with a score <63 had a higher likelihood of achieving Optimal Outcome (OR: 4.8, 95% CI: 1.1-25.8, P =0.033). There was no significant cutoff of invasiveness for the not frail/high deformity group.CONCLUSIONS:Our study correlated increased invasiveness in CD surgery to the risk of DJF, reoperation, and poor clinical success. The thresholds derived for deformity severity and frailty may enable surgeons to individualize the invasiveness of their procedures during surgical planning to account for the heightened risk of adverse events and minimize unfavorable outcomes.

To develop a simplified, modified frailty index for adult spinal deformity (ASD) patients dependent on objective clinical factors. ASD patients with baseline (BL) and 2-year (2Y) follow-up were included. Factors with the largest R2 value derived from multivariate forward stepwise regression were including in the modified ASD-FI (clin-ASD-FI). Factors included in the clin-ASD-FI were regressed against mortality, extended length of hospital stay (LOS, > 8 days), revisions, major complications and weights for the clin-ASD-FI were calculated via Beta/Sullivan. Total clin-ASD-FI score was created with a score from 0 to 1. Linear regression correlated clin-ASD-FI with ASD-FI scores and published cutoffs for the ASD-FI were used to create the new frailty cutoffs: not frail (NF: < 0.11), frail (F: 0.11–0.21) and severely frail (SF: > 0.21). Binary logistic regression assessed odds of complication or reop for frail patients. Five hundred thirty-one ASD patients (59.5 yrs, 79.5

Study Design/Setting: This was a retrospective cohort study. Background: Little is known of the intersection between surgical invasiveness, cervical deformity (CD) severity, and frailty. Objective: The aim of this study was to investigate the outcomes of CD surgery by invasiveness, frailty status, and baseline magnitude of deformity. Methods: This study included CD patients with 1-year follow-up. Patients stratified in high deformity if severe in the following criteria: T1 slope minus cervical lordosis, McGregor’s slope, C2–C7, C2–T3, and C2 slope. Frailty scores categorized patients into not frail and frail. Patients are categorized by frailty and deformity (not frail/low deformity; not frail/high deformity; frail/low deformity; frail/high deformity). Logistic regression assessed increasing invasiveness and outcomes [distal junctional failure (DJF), reoperation]. Within frailty/deformity groups, decision tree analysis assessed thresholds for an invasiveness cutoff above which experiencing a reoperation, DJF or not achieving Good Clinical Outcome was more likely. Results: A total of 115 patients were included. Frailty/deformity groups: 27% not frail/low deformity, 27% not frail/high deformity, 23.5% frail/low deformity, and 22.5% frail/high deformity. Logistic regression analysis found increasing invasiveness and occurrence of DJF [odds ratio (OR): 1.03, 95% CI: 1.01–1.05, P =0.002], and invasiveness increased with deformity severity ( P <0.05). Not frail/low deformity patients more often met Optimal Outcome with an invasiveness index <63 (OR: 27.2, 95% CI: 2.7–272.8, P =0.005). An invasiveness index <54 for the frail/low deformity group led to a higher likelihood of meeting the Optimal Outcome (OR: 9.6, 95% CI: 1.5–62.2, P =0.018). For the frail/high deformity group, patients with a score <63 had a higher likelihood of achieving Optimal Outcome (OR: 4.8, 95% CI: 1.1–25.8, P =0.033). There was no significant cutoff of invasiveness for the not frail/high deformity group. Conclusions: Our study correlated increased invasiveness in CD surgery to the risk of DJF, reoperation, and poor clinical success. The thresholds derived for deformity severity and frailty may enable surgeons to individualize the invasiveness of their procedures during surgical planning to account for the heightened risk of adverse events and minimize unfavorable outcomes.

Background: Given the physical and economic burden of complications in spine surgery, reducing the prevalence of perioperative adverse events is a primary concern of both patients and health care professionals. This study aims to identify specific perioperative factors predictive of developing varying grades of postoperative complications in adult spinal deformity (ASD) patients, as assessed by the Clavien- Dindo complication classification (Cc) system.Methods: Surgical ASD patients >= 18 years were identified in the American College of Surgeons' National Surgical Quality Improvement Program from 2005 to 2015. Postoperative complications were stratified by Cc grade severity: minor (I, II, and III) and severe (IV and V). Stepwise regression models generated dataset-specific predictive models for Cc groups. Model internal validation was achieved by bootstrapping and calculating the area under the curve (AUC) of the model. Significance was set at P < 0.05.Results: Included were 3936 patients (59 +/- 16 years, 63% women, 29 +/- 7 kg/m2) undergoing surgery for ASD (4.4 +/- 4.7 levels, 71% posterior approach, 11% anterior, and 18% combined). Overall, 1% of cases were revisions, 39% of procedures involved decompression, 27% osteotomy, and 15% iliac fixation. Additionally, 66% of patients experienced at least 1 complication, 0% of which were Cc grade I, 51% II, 5% III, 43% IV, and 1% V. The final model predicting severe Cc (IV-V) complications yielded an AUC of 75.6% and included male sex, diabetes, increased operative time, central nervous system tumor, osteotomy, cigarette pack-years, anterior decompression, and anterior lumbar interbody fusion. Final models predicting specific Cc grades were created.Conclusions: Specific predictors of adverse events following ASD-corrective surgery varied for complications of different severities. Multivariate modeling showed smoking rate, osteotomy, diabetes, anterior lumbar interbody fusion, and higher operative time, among other factors, as predictive of severe complications, as classified by the Clavien- Dindo Cc system. These factors can help in the identification of high -risk patients and, consequently, improve preoperative patient counseling.Clinical Relevance: The findings of this study provide a foundation for identifying ASD patients at high risk of postoperative complications . Level of Evidence: 4.

Background: Identify the external applicability of the American College of Surgeons' National Surgical Quality Improvement Program (NSQIP) risk calculator in the setting of adult spinal deformity (ASD) and subsets of patients based on deformity and frailty status.Methods: ASD patients were isolated in our single-center database and analyzed for the shared predictive variables displayed in the NSQIP calculator. Patients were stratified by frailty (not frail <0.03, frail 0.3-0.5, severely frail >0.5), deformity [T1 pelvic angle (TPA) > 30, pelvic incidence minus lumbar lordosis (PI- LL) > 20], and reoperation status. Brier scores were calculated for each variable to validate the calculator's predictability in a single center's database (Quality). External validity of the calculator in our ASD patients was assessed via Hosmer-Lemeshow test, which identified whether the differences between observed and expected proportions are significant.Results: A total of 1606 ASD patients were isolated from the Quality database (48.7 years, 63.8% women, 25.8 kg/m2); 33.4% received decompressions, and 100% received a fusion. For each subset of ASD patients, the calculator predicted lower outcome rates than what was identified in the Quality database. The calculator showed poor predictability for frail, deformed, and reoperation patients for the category "any complication" because they had Brier scores closer to 1. External validity of the calculator in each stratified patient group identified that the calculator was not valid, displaying P values >0.05.Conclusion: The NSQIP calculator was not a valid calculator in our single institutional database. It is unable to comment on surgical complications such as return to operating room, surgical site infection, urinary tract infection, and cardiac complications that are typically associated with poor patient outcomes. Physicians should not base their surgical plan solely on the NSQIP calculator but should consider multiple preoperative risk assessment tools.Level of Evidence: 3. Lumbar Spine

Study Design: Retrospective review of a prospectively enrolled adult spinal deformity (ASD) database. Objective: To investigate what patient factors elevate the risk of sub-optimal outcomes after deformity correction. Background: Currently, it is unknown what factors predict a poor outcome after adult spinal deformity surgery, which may require increased preoperative consideration and counseling. Materials and Methods: Patients >18 yrs undergoing surgery for ASD(scoliosis≥20°, SVA≥5 cm, PT≥25°, or TK≥60°). An unsatisfactory outcome was defined by the following categories met at two years: (1) clinical: deteriorating in ODI at two years follow-up (2) complications/reoperation: having a reoperation and major complication were deemed high risk for poor outcomes postoperatively (HR). Multivariate analyses assessed predictive factors of HR patients in adult spinal deformity patients. Results: In all, 633 adult spinal deformity (59.9 yrs, 79% F, 27.7 kg/m2, CCI: 1.74) were included. Baseline severe Schwab modifier incidence (++): 39.2% pelvic incidence and lumbar lordosis, 28.8% sagittal vertical axis, 28.9% PT. Overall, 15.5% of patients deteriorated in ODI by two years, while 7.6% underwent reoperation and had a major complication. This categorized 11 (1.7%) as HR. HR were more comorbid in terms of arthritis (73%), heart disease (36%), and kidney disease (18%), P<0.001. Surgically, HR had greater EBL (4431ccs) and underwent more osteotomies (91%), specifically Ponte(36%) and Three Column Osteotomies(55%), which occurred more at L2(91%). HR underwent more PLIFs (45%) and had more blood transfusion units (2641ccs), all P<0.050. The multivariate regression determined a combination of a baseline Distress and Risk Assessment Method score in the 75th percentile, having arthritis and kidney disease, a baseline right lower extremity motor score ≤3, cSVA >65 mm, C2 slope >30.2°, CTPA >5.5° for an R 2 value of 0.535 (P<0.001). Conclusions: When addressing adult spine deformities, poor outcomes tend to occur in severely comorbid patients with major baseline psychological distress scores, poor neurologic function, and concomitant cervical malalignment.

Identify trends of navigation and robotic-assisted elective spine surgeries. Elective spine surgery patients between 2007 and 2015 in the Nationwide Inpatient Sample (NIS) were isolated by ICD-9 codes for Navigation [Nav] or Robotic [Rob]-Assisted surgery. Basic demographics and surgical variables were identified via chi-squared and t tests. Each system was analyzed from 2007 to 2015 for trends in usage. Included 3,759,751 patients: 100,488 Nav; 4724 Rob. Nav were younger (56.7 vs 62.7 years), had lower comorbidity index (1.8 vs 6.2, all p < 0.05), more decompressions (79.5 vs 42.6

Background. - Studies have utilized psychological questionnaires to identify the psychological distress among certain surgical populations. Research Question. - Is there an additional psychological burden among patients undergoing surgical treatment for their symptomatic degenerative cervical disease? Materials and methods. - Patients > 18 years of age with symptomatic, degenerative cervical spine dis-ease were included and prospectively enrolled. Correlations and multivariable logistic regression analysis assessed the relationship between these mental health components (PCS, FABQ) and the severity of dis-ability described by the NDI, EQ-5D, and mJOA score. Patient distress scores were compared to previously published benchmarks for other diagnoses. Results. - 47 patients were enrolled (age: 56.0 years,BMI: 29.7 kg/m2). Increasing neck disability and decreasing EQ-5D were correlated with greater PCS and FABQ(all P< 0.001). Patients with severe psycho-logical distress at baseline were more likely to report severe neck disability, while physician-reported mJOA had weaker associations. Compared to historical controls of lumbar patients, patients in our study had greater levels of psychological distress, as measured by FABQ (40.0 vs. 17.6; P< 0.001) and PCS (27.4 vs. 19.3;P< 0.001). Discussion and Conclusion. - Degenerative cervical spine patients seeking surgery were found to have a significant level of psychological distress, with a large portion reporting severe fear avoidance beliefs and catastrophizing pain at baseline. Strong correlation was seen between patient-reported functional met-rics, but less so with physician-reported signs and symptoms. Additionally, this population demonstrated higher psychological burden in certain respects than previously identified benchmarks of patients with other disorders. Preoperative treatment to help mitigate this distress, impact postoperative outcomes, and should be further investigated. Level of Evidence. - Level III. (c) 2022 Elsevier Masson SAS. All rights reserved.

Adult cervical deformity is a structural malalignment of the cervical spine that may present with variety of significant symptomatology for patients. There are clear and substantial negative impacts of cervical spine deformity, including the increased burden of pain, limited mobility and functionality, and interference with patients’ ability to work and perform everyday tasks. Primary cervical deformities develop as the result of a multitude of different etiologies, changing the normal mechanics and structure of the cervical region. In particular, degeneration of the cervical spine, inflammatory arthritides and neuromuscular changes are significant players in the development of disease. Additionally, cervical deformities, sometimes iatrogenically, may present secondary to malalignment or correction of the thoracic, lumbar or sacropelvic spine. Previously, classification systems were developed to help quantify disease burden and influence management of thoracic and lumbar spine deformities. Following up on these works and based on the relationship between the cervical and distal spine, Ames-ISSG developed a framework for a standardized tool for characterizing and quantifying cervical spine deformities. When surgical intervention is required to correct a cervical deformity, there are advantages and disadvantages to both anterior and posterior approaches. A stepwise approach may minimize the drawbacks of either an anterior or posterior approach alone, and patients should have a surgical plan tailored specifically to their cervical deformity based upon symptomatic and radiographic indications. This state-of-the-art review is based upon a comprehensive overview of literature seeking to highlight the normal cervical spine, etiologies of cervical deformity, current classification systems, and key surgical techniques.

Study Design: Retrospective review of Kids' Inpatient Database (KID). Purpose: Identify the risks and complications associated with surgery in adolescents diagnosed with Chiari and scoliosis. Overview of Literature: Scoliosis is frequently associated with Chiari malformation (CM). More specifically, reports have been made about this association with CM type I in the absence of syrinx status. Methods: The KID was used to identify all pediatric inpatients with CM and scoliosis. The patients were stratified into three groups: those with concomitant CM and scoliosis (CMS group), those with only CM (CM group), and those with only scoliosis (Sc group). Multivariate logistic regressions were used to assess association between surgical characteristics and diagnosis with complication rate. Results: A total of 90,707 spine patients were identified (61.8% Sc, 37% CM, 1.2% CMS). Sc patients were older, had a higher invasiveness score, and higher Charlson comorbidity index (all p<0.001). CMS patients had significantly higher rates of surgical decompression (36.7%). Sc patients had significantly higher rates of fusions (35.3%) and osteotomies (1.2%, all p<0.001). Controlling for age and invasiveness, postoperative complications were significantly associated with spine fusion surgery for Sc patients (odds ratio [OR], 1.8; p<0.05). Specifically, posterior spinal fusion in the thoracolumbar region had a greater risk of complications (OR, 4.9) than an anterior approach (OR, 3.6; all p<0.001). CM patients had a significant risk of complications when an osteotomy was performed as part of their surgery (OR, 2.9) and if a spinal fusion was concurrently performed (OR, 1.8; all p<0.05). Patients in the CMS cohort were significantly likely to develop postoperative complications if they underwent a spinal fusion from both anterior (OR, 2.5) and posterior approach (OR, 2.7; all p<0.001). Conclusions: Having concurrent scoliosis and CM increases operative risk for fusion surgeries despite approach. Being independently inflicted with scoliosis or Chiari leads to increased complication rate when paired with thoracolumbar fusion and osteotomies; respectively.

STUDY DESIGN:Retrospective review of a prospectively enrolled adult spinal deformity (ASD) database. OBJECTIVE:To investigate what patient factors elevate the risk of sub-optimal outcomes after deformity correction. BACKGROUND:Currently, it is unknown what factors predict a poor outcome after adult spinal deformity surgery, which may require increased preoperative consideration and counseling. MATERIALS AND METHODS:Patients >18 yrs undergoing surgery for ASD(scoliosis≥20°, SVA≥5 cm, PT≥25°, or TK≥60°). An unsatisfactory outcome was defined by the following categories met at two years: (1) clinical: deteriorating in ODI at two years follow-up (2) complications/reoperation: having a reoperation and major complication were deemed high risk for poor outcomes postoperatively (HR). Multivariate analyses assessed predictive factors of HR patients in adult spinal deformity patients. RESULTS:In all, 633 adult spinal deformity (59.9 yrs, 79% F, 27.7 kg/m 2, CCI: 1.74) were included. Baseline severe Schwab modifier incidence (++): 39.2% pelvic incidence and lumbar lordosis, 28.8% sagittal vertical axis, 28.9% PT. Overall, 15.5% of patients deteriorated in ODI by two years, while 7.6% underwent reoperation and had a major complication. This categorized 11 (1.7%) as HR. HR were more comorbid in terms of arthritis (73%), heart disease (36%), and kidney disease (18%), P <0.001. Surgically, HR had greater EBL (4431ccs) and underwent more osteotomies (91%), specifically Ponte(36%) and Three Column Osteotomies(55%), which occurred more at L2(91%). HR underwent more PLIFs (45%) and had more blood transfusion units (2641ccs), all P <0.050. The multivariate regression determined a combination of a baseline Distress and Risk Assessment Method score in the 75th percentile, having arthritis and kidney disease, a baseline right lower extremity motor score ≤3, cSVA >65 mm, C2 slope >30.2°, CTPA >5.5° for an R2 value of 0.535 ( P <0.001). CONCLUSIONS:When addressing adult spine deformities, poor outcomes tend to occur in severely comorbid patients with major baseline psychological distress scores, poor neurologic function, and concomitant cervical malalignment.

BACKGROUND:The International Spine Study Group (ISSG) and the European Spine Study Group (ESSG) developed an adult spinal deformity (ASD) risk calculator based on one of the most granular, prospective ASD databases. The calculator utilizes preoperative radiographic, surgical, and patient-specific variables to predict patient-reported outcomes and complication rates at 2 years. Our aim was to assess the ISSG-ESSG risk calculator's usability in a single-institution ASD population.METHODS:Frail ([F], 0.3 > 0.5) ASD patients were isolated in a single-center ASD database. Basic demographics were assessed via χ 2 and t tests. Each F patient was inputted into the ESSG risk calculator to identify individual predictive rates for postoperative 2-year health-related quality of life questions (HRQL) outcomes and major complications. These calculated predicted outcomes were analyzed against those identified from the ASD database in order to validate the calculator's predictability via Brier scores. A score closer to 1 meant the ISSG-ESSG calculator was not predictive of that specific outcome. A score closer to 0 meant the ISSG-ESSG calculator was a predictive tool for that factor.RESULTS:A total of 631 ASD patients were isolated (55.8 ± 16.8 years, 26.68 kg/m2, 0.95 ± 1.3 Charlson Comorbidity Index). Of those patients, 7.8% were frail. Fifty percent of frail patients received an interbody fusion, 58.3% received a decompression, and 79.2% underwent osteotomy. Surgical details were as follows: mean operative time was 342.9 ± 94.3 minutes, mean estimated blood loss was 2131.82 ± 1011 mL, and average length of stay was 7.12 ± 2.5 days. The ISSG-ESSG calculator predicted the likelihood of improvement for the following HRQL's: Oswestry Disability Index (ODI) (86%), Scoliosis Research Society (SRS)-22 mental health (71.1%), SRS-22 total (87.6%), and major complication (53.4%). The single institution had lower percentages of improvement in ODI (24.6%), SRS-22 mental health (21.3%), SRS-22 total (25.1%), and lower presence of major complication (34.8%). The calculated Brier scores identified the calculator's predictability for each factor was as follows: ODI (0.24), SRS-22 mental health (0.21), SRS-22 total (0.25), and major complication (0.28).CONCLUSIONS:All of the variables had low Brier scores, indicating that the ISSG-ESSG calculator can be used as a predictive tool for ASD frail patients.LEVEL OF EVIDENCE: 3:

Background: Metabolic syndrome (MetS) is an amalgamation of medical disorders that ultimately increase patient complications. Factors such as obesity. hypertension. dyslipidemia, and diabetes are associated with this disease complex. Objective: To assess the incremental value of improving MetS in relation to clinical outcomes. Study Design: Retrospective cohort study. Methods: Patients undergoing elective spine surgery were isolated and separated into 2 groups: MetS patients (>2 metabolic variables: hypertension. diabetes, obesity, and triglycerides) and nonmetabolic patients (<2 metabolic variables). T tests and chi(2) tests compared differences in patient demographics. Resolution of metabolic factors was incrementally analyzed for their effect on perioperative complications through utilization of logistic regressions. Results: A total of 2,855.517 elective spine patients were included. Of them, 20.1% had MeTS (81.4% two factors, 18.4% three factors, 0.2% four factors). MetS patients were older, less female, and more comorbid (P < 0.001). About 28.8% MetS patients developed more complications such as anemia (9.8% vs 5.9%), device related (3.5% vs 2.9%), neurologic (2.3% vs 1.4%), and bowel issues (9.7% vs 6.8 %: P < 0.05). Controlling for age and procedure invasiveness, having 3 MetS factors increased a patient's likelihood (0.89x) of developing a perioperative complication (P < 0.05), whereas 2 factors had lower odds (0.82). More specifically, patients who were diabetes, obese, and had hypertension had the greatest odds at developing a complication (058 [0.58-0.57]) followed by those who had concomitant hypertension, high triglycerides, and were obese (0.55 [0.63-0.48J; all P < 0.001). MetS patients with 2 factors, being obese and having hypertension produced the lowest odds at developing a complication (0.5 [0.61-0.43]; P < 0.001). These MetS patients also had a lower length of stay than those with 3 and 4 (P < 0.001). Conclusions: Metabolic patients improved in perioperative complications incrementally, demonstrating the utility of efforts to mitigate burden of MetS even if not completely abolished.

BACKGROUND:Persistent pelvic compensation following adult spinal deformity (ASD) corrective surgery may impair quality of life and result in persistent pathologic lower extremity compensation. Ideal age-specific alignment targets have been proposed to improve surgical outcomes, though it is unclear whether reaching these ideal targets reduces rates of pelvic nonresponse following surgery. Our aim was to assess the relationship between pelvic nonresponse, age-specific alignment, and lower-limb compensation following surgery for ASD.METHODS:Single-center retrospective cohort study. ASD patients were grouped: those who did not improve in Scoliosis Research Society-Schwab pelvic tilt (PT) modifier (pelvic nonresponders [PNR]), and those who improved (pelvic responders [PR]). Groups were propensity score matched for preoperative PT and assessed for differences in spinal and lower extremity alignment. Rates of pelvic nonresponse were compared across patient groups who were undercorrected, overcorrected, or matched age-specific postoperative alignment targets.RESULTS:A total of 146 surgical ASD patients, 47.9% of whom showed pelvic nonresponse following surgery, were included. After propensity score matching, PNR (N = 29) and PR (N = 29) patients did not differ in demographics, preoperative alignment, or levels fused; however, PNR patients have less preoperative knee flexion (9° vs 14°, P = 0.043). PNR patients had inferior postoperative pelvic incidence and lumbar lordosis (PI-LL) alignment (17° vs 3°) and greater pelvic shift (53 vs 31 mm). PNR and PR patients did not differ in rates of reaching ideal age-specific postoperative alignment for sagittal vertical axis (SVA) or PI-LL, though patients who matched ideal PT had lower rates of PNR (25.0% vs 75.0%). For patients with moderate and severe preoperative SVA, more aggressive correction relative to either ideal postoperative PT or PI-LL was associated with significantly lower rates of pelvic nonresponse (all P < 0.05).CONCLUSIONS:For patients with moderate to severe baseline truncal inclination, more aggressive surgical correction relative to ideal age-specific PI-LL was associated with lower rates of pelvic nonresponse. Postoperative alignment targets may need to be adjusted to optimize alignment outcomes for patients with substantial preoperative sagittal deformity.CLINICAL RELEVANCE:These findings increase our understanding of the poor outcomes that occur despite ideal realignment. Surgical correction of severe global sagittal deformity should be prioritized to mitigate these occurrences.LEVEL OF EVIDENCE: 3:

Hypothesis:The myelopathy-based cervical deformity (CD) thresholds will associate with patient-reported outcomes and complications. Materials and Methods:This study include CD patients (C2-C7 Cobb > 10°, CL > 10°, cervical sagittal vertical axis > 4 cm, or CBVA > 25°) with BL and 1-year (1Y) data. Modifiers assessed low (L), moderate (M), and severe (S) deformity: CL (L: >3°; M:-21° to 3°; S: <‒21°), TS-CL (L: <26°; M: 26° to 45°; S: >45°), C2-T3 angle (L: >‒25°; M:-35° to-25°; S: <‒35°), C2 slope (L: <33°; M: 33° to 49°; S: >49°), MGS (L: >‒9° and < 0°; M: ‒12° to ‒9° or 0° to 19°; S: < ‒12° or > 19°), and frailty (L: <0.18; M: 0.18-0.27, S: >0.27). Means comparison and ANOVA assessed outcomes in the severity groups at BL at 1Y. Correlations found between modifiers assessed the internal relationship. Results:One hundred and four patients were included in the study (57.1 years, 50%, 29.3 kg/m2). Baseline S TS-CL, C2-T3, and C2S modifiers were associated with increased reoperations (P < 0.01), while S MGS, CL, and C2-T3 had increased estimated blood lost (>1000ccs, P < 0.001). S MGS and C2-T3 had more postop DJK (60%, P = 0.018). Improvement in TS-CL, C2S, C2-T3, and CL patients had better numeric rating scale (NRS) back (<5) and EuroQOL 5-Dimension questionnaire (EQ5D) at 1 year (P < 0.05). Improving the modifiers correlated strongly with each other (0.213-0.785, P < 0.001). Worsened TS-CL had increased NRS back scores at 1 year (9, P = 0.042). Worsened CL had increased 1-year modified Japanese Orthopedic Association (mJOA) (7, P = 0.001). Worsened C2-T3 had worse NRS neck scores at 1 year (P = 0.048). Improvement in all six modifiers (8.7%) had significantly better health-related quality of life (HRQL) scores at follow-up (EQ5D, NRS, and Neck Disability Index). Conclusions:Newly proposed CD modifiers based on mJOA were closely associated with outcomes. Improvement and deterioration in the modifiers significantly impacted the HRQL.

Purpose. Despite adequate correction, the pelvis may fail to readjust, deemed pelvic nonresponse (PNR). To assess alignment outcomes [PNR, proximal junctional kyphosis (PJK), postoperative cervical deformity (CD)] following adult spinal deformity (ASD) surgery utilizing different realignment strategies. Materials and Methods. ASD patients with two-year data were included. PNR defined as undercorrected in age-adjusted pelvic tilt (PT) at six weeks and maintained at two years. Patients classified by alignment utilities: (a) improvement in Scoliosis Research Society-Schwab sagittal vertical axis, (b) matching in age-adjusted pelvic incidence−lumbar lordosis, (c) matching in Roussouly, (d) aligning Global Alignment and Proportionality (GAP) score. Multivariable regression analyses, controlling for age, baseline deformity, and surgical factors, assessed rates of PNR, PJK, and CD development following realignment. Results. A total of 686 patients met the inclusion criteria. Rates of postoperative PJK and CD were not significant in the PNR group (both P>0.15). PNR patients less often met substantial clinical benefit in Oswestry Disability Index by two years [odds ratio: 0.6 (0.4–0.98)]. Patients overcorrected in age-adjusted pelvic incidence−lumbar lordosis, matching Roussouly, or proportioned in GAP at six weeks had lower rates of PNR (all P<0.001). Incremental addition of classifications led to 0% occurrence of PNR, PJK, and CD. Stratifying by baseline PT severity, Low and moderate deformity demonstrated the least incidence of PNR (7.7%) when proportioning in GAP at six weeks, while severe PT benefited most from matching in Roussouly (all P<0.05). Conclusions. Following ASD corrective surgery, 24.9% of patients showed residual pelvic malalignment. This occurrence was often accompanied by undercorrection of lumbopelvic mismatch and less improvement of pain. However, overcorrection in any strategy incurred higher rates of PJK. We recommend surgeons identify a middle ground using one, or more, of the available classifications to inform correction goals in this regard. Level of Evidence. III.

Background: Recent studies have evaluated the correlation of health-related quality of life (HRQL) scores with radiographic parameters. This relationship may provide insight into the connection of patient-reported disability and disease burden caused by cervical diagnoses. Purpose: To evaluate the association between spinopelvic sagittal parameters and HRQLs in patients with primary cervical diagnoses. Methods: Patients ≥18 years meeting criteria for primary cervical diagnoses. Cervical radiographic parameters assessed cervical sagittal vertical axis, TS-CL, chin-to-brow vertical angle, C2-T3, CL, C2 Slope, McGregor's slope. Global radiographic alignment parameters assessed PT, SVA, PI-LL, T1 Slope. Pearson correlations were run for all combinations at baseline (BL) and 1 year (1Y) for continuous BL and 1Y modified Japanese Orthopaedic Association scale (mJOA) scores, as well as decline or improvement in those HRQLs at 1Y. Multiple linear regression models were constructed to investigate BL and 1Y alignment parameters as independent variables. Results: Ninety patients included 55.6 ± 9.6 years, 52% female, 30.7 ± 7kg/m2. By approach, 14.3% of patients underwent procedures by anterior approach, 56% posterior, and 30% had combined approaches. Average anterior levels fused: 3.6, posterior: 4.8, and mean total number of levels fused: 4.5. Mean operative time for the cohort was 902.5 minutes with an average estimated blood loss of 830 ccs. The mean BL neck disability index (NDI) score was 56.5 and a mJOA of 12.81. While BL NDI score correlated with gender (P = 0.050), it did not correlate with BL global or cervical radiographic factors. An increased NDI score at 1Y postoperatively correlated with BL body mass index (P = 0.026). A decreased NDI score was associated with 1Y T12-S1 angle (P = 0.009) and 1Y T10 L2 angle (P = 0.013). Overall, BL mJOA score correlated with the BL radiographic factors of T1 slope (P = 0.005), cervical lordosis (P = 0.001), C2-T3 (P = 0.008), C2 sacral slope (P = 0.050), SVA (P = 0.010), and CL Apex (P = 0.043), as well as gender (P = 0.050). Linear regression modeling for the prior independent variables found a significance of P = 0.046 and an R2 of 0.367. Year 1 mJOA scores correlated with 1Y values for maximum kyphosis (P = 0.043) and TS-CL (P = 0.010). At 1Y, a smaller mJOA score correlated with BL S1 sacral slope (P = 0.014), pelvic incidence (P = 0.009), L1-S1 (P = 0.012), T12-S1 (P = 0.008). The linear regression model for those 4 variables demonstrated an R2 of 0.169 and a P = 0.005. An increased mJOA score correlated with PI-LL difference at 1Y (P = 0.012), L1-S1 difference (P = 0.036), T12-S1 difference (0.006), maximum lordosis (P = 0.026), T9-PA difference (P = 0.010), and difference of T4-PA (P = 0.008). Conclusions: While the impact of preoperative sagittal and cervical parameters on mJOA was strong, the BL radiographic factors did not impact NDI scores. PostOp HRQL was significantly associated with sagittal parameters for mJOA (both worsening and improvement) and NDI scores (improvement). When cervical surgery has been indicated, radiographic alignment is important for postoperative HRQL.