Browsing by Author "Schoenfeld, Andrew J"
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Item Open Access Are We Focused on the Wrong Early Postoperative Quality Metrics? Optimal Realignment Outweighs Perioperative Risk in Adult Spinal Deformity Surgery.(Journal of clinical medicine, 2023-08) Passias, Peter G; Williamson, Tyler K; Mir, Jamshaid M; Smith, Justin S; Lafage, Virginie; Lafage, Renaud; Line, Breton; Daniels, Alan H; Gum, Jeffrey L; Schoenfeld, Andrew J; Hamilton, David Kojo; Soroceanu, Alex; Scheer, Justin K; Eastlack, Robert; Mundis, Gregory M; Diebo, Bassel; Kebaish, Khaled M; Hostin, Richard A; Gupta, Munish C; Kim, Han Jo; Klineberg, Eric O; Ames, Christopher P; Hart, Robert A; Burton, Douglas C; Schwab, Frank J; Shaffrey, Christopher I; Bess, Shay; On Behalf Of The International Spine Study GroupBackground
While reimbursement is centered on 90-day outcomes, many patients may still achieve optimal, long-term outcomes following adult spinal deformity (ASD) surgery despite transient short-term complications.Objective
Compare long-term clinical success and cost-utility between patients achieving optimal realignment and suboptimally aligned peers.Study design/setting
Retrospective cohort study of a prospectively collected multicenter database.Methods
ASD patients with two-year (2Y) data included. Groups were propensity score matched (PSM) for age, frailty, body mass index (BMI), Charlson Comorbidity Index (CCI), and baseline deformity. Optimal radiographic criteria are defined as meeting low deformity in all three (Scoliosis Research Society) SRS-Schwab parameters or being proportioned in Global Alignment and Proportionality (GAP). Cost-per-QALY was calculated for each time point. Multivariable logistic regression analysis and ANCOVA (analysis of covariance) adjusting for baseline disability and deformity (pelvic incidence (PI), pelvic incidence minus lumbar lordosis (PI-LL)) were used to determine the significance of surgical details, complications, clinical outcomes, and cost-utility.Results
A total of 930 patients were considered. Following PSM, 253 "optimal" (O) and 253 "not optimal" (NO) patients were assessed. The O group underwent more invasive procedures and had more levels fused. Analysis of complications by two years showed that the O group suffered less overall major (38% vs. 52%, p = 0.021) and major mechanical complications (12% vs. 22%, p = 0.002), and less reoperations (23% vs. 33%, p = 0.008). Adjusted analysis revealed O patients more often met MCID (minimal clinically important difference) in SF-36 PCS, SRS-22 Pain, and Appearance. Cost-utility-adjusted analysis determined that the O group generated better cost-utility by one year and maintained lower overall cost and costs per QALY (both p < 0.001) at two years.Conclusions
Fewer late complications (mechanical and reoperations) are seen in optimally aligned patients, leading to better long-term cost-utility overall. Therefore, the current focus on avoiding short-term complications may be counterproductive, as achieving optimal surgical correction is critical for long-term success.Item Open Access Comparing and Contrasting the Clinical Utility of Sagittal Spine Alignment Classification Frameworks: Roussouly Versus SRS-Schwab.(Spine, 2022-03) Passias, Peter G; Bortz, Cole; Pierce, Katherine E; Passfall, Lara; Kummer, Nicholas A; Krol, Oscar; Lafage, Renaud; Diebo, Bassel G; Lafage, Virginie; Ames, Christopher P; Burton, Douglas C; Gupta, Munish C; Sciubba, Daniel M; Schoenfeld, Andrew J; Bess, Shay; Hostin, Richard; Shaffrey, Christopher I; Line, Breton G; Klineberg, Eric O; Smith, Justin S; Schwab, Frank J; International Spine Study GroupStudy design
Retrospective cohort study of a prospectively collected database.Objective
To compare clinical utility of two common classification systems for adult spinal deformity (ASD) and determine whether both should be considered in surgical planning to improve patient outcomes.Summary of background data
Surgical restoration of appropriate Roussouly classification shape or SRS-Schwab ASD classification may improve outcomes.Methods
ASD patients with pre- and 2-year postop (2Y) radiographic/health-related quality of life (HRQL) data were grouped by "theoretical" and "current" Roussouly type. Univariate analyses assessed outcomes of patients who mismatched Roussouly types at both pre- and 2Y intervals (Mismatched) and those of preoperative mismatched patients who matched at 2-years (Matched). Subanalysis assessed outcomes of patients who improved in Schwab modifiers, and patients who both improved in both Schwab modifiers and matched Roussouly type by 2Y.Results
Included: 515 ASD patients (59 ± 14 yrs, 80% F). Preoperative breakdown of "current" Roussouly types: Type 1 (10%), 2 (54%), 3 (24%), and 4 (12%). Matched and Mismatched groups did not differ in rates of reaching MCID for any HRQL metrics by 2Y (all P > 0.10). Reoperation, PJK, and complications did not differ between Matched and Mismatched (all P > 0.10), but Roussouly Matched patients had toward lower rates of instrumentation failure (17.2% vs. 24.8%, P = 0.038). By 2Y, 28% of patients improved in PT Schwab modifier, 37% in SVA, and 46% in PI-LL. Patients who both Matched Roussouly at 2Y and improved in all Schwab modifiers met MCID for Oswestry Disability Index (ODI) and Scoliosis Research Society (SRS) activity at higher rates than patients who did not.Conclusion
Isolated restoration per the Roussouly system was not associated with superior outcomes. Patients who both matched Roussouly type and improved in Schwab modifiers had superior patient-reported outcomes at 2-years. Concurrent consideration of both systems may offer utility in establishing optimal realignment goals.Level of Evidence: 3.Item Open Access Cost Benefit of Implementation of Risk Stratification Models for Adult Spinal Deformity Surgery.(Global Spine J, 2023-12-11) Passias, Peter G; Williamson, Tyler K; Kummer, Nicholas A; Pellisé, Ferran; Lafage, Virginie; Lafage, Renaud; Serra-Burriel, Miguel; Smith, Justin S; Line, Breton; Vira, Shaleen; Gum, Jeffrey L; Haddad, Sleiman; Sánchez Pérez-Grueso, Francisco Javier; Schoenfeld, Andrew J; Daniels, Alan H; Chou, Dean; Klineberg, Eric O; Gupta, Munish C; Kebaish, Khaled M; Kelly, Michael P; Hart, Robert A; Burton, Douglas C; Kleinstück, Frank; Obeid, Ibrahim; Shaffrey, Christopher I; Alanay, Ahmet; Ames, Christopher P; Schwab, Frank J; Hostin, Richard A; Bess, Shay; International Spine Study GroupSTUDY DESIGN/SETTING: Retrospective cohort study. OBJECTIVE: Assess the extent to which defined risk factors of adverse events are drivers of cost-utility in spinal deformity (ASD) surgery. METHODS: ASD patients with 2-year (2Y) data were included. Tertiles were used to define high degrees of frailty, sagittal deformity, blood loss, and surgical time. Cost was calculated using the Pearl Diver registry and cost-utility at 2Y was compared between cohorts based on the number of risk factors present. Statistically significant differences in cost-utility by number of baseline risk factors were determined using ANOVA, followed by a generalized linear model, adjusting for clinical site and surgeon, to assess the effects of increasing risk score on overall cost-utility. RESULTS: By 2 years, 31% experienced a major complication and 23% underwent reoperation. Patients with ≤2 risk factors had significantly less major complications. Patients with 2 risk factors improved the most from baseline to 2Y in ODI. Average cost increased by $8234 per risk factor (R2 = .981). Cost-per-QALY at 2Y increased by $122,650 per risk factor (R2 = .794). Adjusted generalized linear model demonstrated a significant trend between increasing risk score and increasing cost-utility (r2 = .408, P < .001). CONCLUSIONS: The number of defined patient-specific and surgical risk factors, especially those with greater than two, were associated with increased index surgical costs and diminished cost-utility. Efforts to optimize patient physiology and minimize surgical risk would likely reduce healthcare expenditures and improve the overall cost-utility profile for ASD interventions.Level of evidence: III.Item Open Access Critical Analysis of Radiographic and Patient Reported Outcomes Following Anterior/Posterior Staged vs. Same Day Surgery in Patients Undergoing Identical Corrective Surgery for Adult Spinal Deformity.(Spine, 2023-07) Passias, Peter G; Ahmad, Waleed; Tretiakov, Peter S; Lafage, Renaud; Lafage, Virginie; Schoenfeld, Andrew J; Line, Breton; Daniels, Alan; Mir, Jamshaid M; Gupta, Munish; Mundis, Gregory; Eastlack, Robert; Nunley, Pierce; Hamilton, D Kojo; Hostin, Richard; Hart, Robert; Burton, Douglas C; Shaffrey, Christopher; Schwab, Frank; Ames, Christopher; Smith, Justin S; Bess, Shay; Klineberg, Eric O; International Spine Study GroupStudydesign
Retrospective cohort study of a prospectively collected multi-center adult spinal deformity (ASD) database.Objective
To compare staged procedures to same-day interventions and identify the optimal time interval between staged surgeries for treatment of ASD.Background
Surgical intervention for ASD is invasive and complex procedure that surgeons often elect to perform on different days (staging). Yet, there remains a paucity of literature on the timing and effects of the interval between stages.Methods
ASD patients with two-year (2Y) data undergoing an anterior/posterior (A/P) fusion to the ilium were included. Propensity score matching (PSM) was performed for number of levels fused, number of interbody devices, surgical approaches, number of osteotomies/three-column osteotomy (3CO), frailty, Oswestry Disability Index (ODI), Charlson Comorbidity Index (CCI), revisions, sagittal vertical axis (SVA), pelvic incidence-lumbar lordosis (PI-LL), and UIV to create balanced cohorts of Same-Day and Staged surgical patients. Staged patients were stratified by intervening time-period between surgeries, using quartiles.Results
176 PSM patients were included. Median interval between A/P staged procedures was 3 days. Staged patients had greater operative time and lower ICU stays postop (P<0.05). At 2Y, staged compared to same day showed a greater improvement in T1 slope - cervical lordosis (TS-CL), C2 sacral slope (C2SS), and SRS-Schwab SVA (P<0.05). Staged patients had higher rates of minimal clinically-important difference (MCID) for 1Y SRS-Appearance and 2Y physical component summary (PCS) scores. Assessing different intervals of staging, patients at the 75th percentile interval showed greater improvement in 1Y SRS Pain and Total postop as well as SRS Activity, Pain, Satisfaction, and Total scores (P<0.05) compared to patients in lower quartiles. Compared to the 25th percentile, patients reaching the 50th percentile interval were associated with increased odds of improvement in Global Alignment and Proportion (GAP) score proportionality (9.3[1.6-53.2], P=0.01).Conclusions
This investigation is among the first to compare multicenter staged and same day surgery anterior/posterior adult spinal deformity patients fused to ilium using propensity-matching. Staged procedures resulted in significant improvement radiographically, reduced ICU admissions, and superior patient reported outcomes compared to same day procedures. An interval of at least three days between staged procedures is associated with superior outcomes in terms of GAP score proportionality.Item Open Access Development of a modified frailty index for adult spinal deformities independent of functional changes following surgical correction: a true baseline risk assessment tool.(Spine deformity, 2024-02) Passias, Peter G; Pierce, Katherine E; Mir, Jamshaid M; Krol, Oscar; Lafage, Renaud; Lafage, Virginie; Line, Breton; Uribe, Juan S; Hostin, Richard; Daniels, Alan; Hart, Robert; Burton, Douglas; Shaffrey, Christopher; Schwab, Frank; Diebo, Bassel G; Ames, Christopher P; Smith, Justin S; Schoenfeld, Andrew J; Bess, Shay; Klineberg, Eric O; International Spine Study GroupPurpose
To develop a simplified, modified frailty index for adult spinal deformity (ASD) patients dependent on objective clinical factors.Methods
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.Results
Five hundred thirty-one ASD patients (59.5 yrs, 79.5% F) were included. The final model had a R2 of 0.681, and significant factors were: < 18.5 or > 30 BMI (weight: 0.0625 out of 1), cardiac disease (0.125), disability employment status (0.3125), diabetes mellitus (0.0625), hypertension (0.0625), osteoporosis (0.125), blood clot (0.1875), and bowel incontinence (0.0625). These factors calculated the score from 0 to 1, with a mean cohort score of 0.13 ± 0.14. Breakdown by clin-ASD-FI score: 51.8% NF, 28.1% F, 20.2% SF. Increasing frailty severity was associated with longer LOS (NF: 7.0, F: 8.3, SF: 9.2 days; P < 0.001). Frailty independently predicted occurrence of any complication (OR: 9.357 [2.20-39.76], P = 0.002) and reop (OR: 2.79 [0.662-11.72], P = 0.162).Conclusions
Utilizing an existing ASD frailty index, we proposed a modified version eliminating the patient-reported components. This index is a true assessment of physiologic status, and represents a superior risk factor assessment compared to other tools for both primary and revision spinal deformity surgery as a result of its immutability with surgery, lack of subjectivity, and ease of use.Item Open Access Development of Risk Stratification Predictive Models for Cervical Deformity Surgery.(Neurosurgery, 2022-12) Passias, Peter G; Ahmad, Waleed; Oh, Cheongeun; Imbo, Bailey; Naessig, Sara; Pierce, Katherine; Lafage, Virginie; Lafage, Renaud; Hamilton, D Kojo; Protopsaltis, Themistocles S; Klineberg, Eric O; Gum, Jeffrey; Schoenfeld, Andrew J; Line, Breton; Hart, Robert A; Burton, Douglas C; Bess, Shay; Schwab, Frank J; Smith, Justin S; Shaffrey, Christopher I; Ames, Christopher P; International Spine Study GroupBackground
As corrective surgery for cervical deformity (CD) increases, so does the rate of complications and reoperations. To minimize suboptimal postoperative outcomes, it is important to develop a tool that allows for proper preoperative risk stratification.Objective
To develop a prognostic utility for identification of risk factors that lead to the development of major complications and unplanned reoperations.Methods
CD patients age 18 years or older were stratified into 2 groups based on the postoperative occurrence of a revision and/or major complication. Multivariable logistic regressions identified characteristics that were associated with revision or major complication. Decision tree analysis established cutoffs for predictive variables. Models predicting both outcomes were quantified using area under the curve (AUC) and receiver operating curve characteristics.Results
A total of 109 patients with CD were included in this study. By 1 year postoperatively, 26 patients experienced a major complication and 17 patients underwent a revision. Predictive modeling incorporating preoperative and surgical factors identified development of a revision to include upper instrumented vertebrae > C5, lowermost instrumented vertebrae > T7, number of unfused lordotic cervical vertebrae > 1, baseline T1 slope > 25.3°, and number of vertebral levels in maximal kyphosis > 12 (AUC: 0.82). For developing a major complication, a model included a current smoking history, osteoporosis, upper instrumented vertebrae inclination angle < 0° or > 40°, anterior diskectomies > 3, and a posterior Smith Peterson osteotomy (AUC: 0.81).Conclusion
Revisions were predicted using a predominance of radiographic parameters while the occurrence of major complications relied on baseline bone health, radiographic, and surgical characteristics.Item Open Access Efficacy of Varying Surgical Approaches on Achieving Optimal Alignment in Adult Spinal Deformity Surgery.(Spine, 2023-07) Passias, Peter G; Ahmad, Waleed; Williamson, Tyler K; Lebovic, Jordan; Kebaish, Khaled; Lafage, Renaud; Lafage, Virginie; Line, Breton; Schoenfeld, Andrew J; Diebo, Bassel G; Klineberg, Eric O; Kim, Han Jo; Ames, Christopher P; Daniels, Alan H; Smith, Justin S; Shaffrey, Christopher I; Burton, Douglas C; Hart, Robert A; Bess, Shay; Schwab, Frank J; Gupta, Munish C; International Spine Study GroupBackground
The Roussouly, SRS-Schwab, and GAP classifications define alignment by spinal shape and deformity severity. The efficacy of different surgical approaches and techniques to successfully achieve these goals is not well understood.Purpose
Identify the impact of surgical approach and/or technique on meeting complex realignment goals in adult spinal deformity(ASD) corrective-surgery.Study design/setting
Retrospective.Methods
Included: ASD patients fused to pelvis with two-year(2Y) data. Patients were categorized by: 1)Roussouly: matching current and theoretical spinal shapes; 2)improving in SRS-Schwab modifiers(0, +, ++); 3)improving GAP Proportionality by 2Y. ANCOVA and multivariable logistic regression analyses controlling for age, levels fused, baseline deformity, and three-column osteotomy usage compared the effect of different surgical approaches, interbody and osteotomy use on meeting realignment goals.Results
693 ASD patients were included. By surgical approach, 65.7% were posterior-only and 34.3% underwent anterior-posterior(AP) approach with 76% receiving an osteotomy(21.8% 3CO). By 2Y, 34% matched Roussouly, 58% improved in GAP, 45% in SRS-Schwab PT, 62% SVA, and 70% PI-LL. Combined approaches were most effective for improvement in PT(OR: 1.7,[1.1-2.5]) and GAP(OR: 2.2,[1.5-3.2]). Specifically, ALIFs below L3 demonstrated higher rates of improvement versus TLIFs in Roussouly(OR: 1.7, [1.1-2.5]) and GAP(OR: 1.9, [1.3-2.7]). Patients undergoing PSO at L3 or L4 were more likely to improve in PT(OR: 2.0,[1.0-5.2]) and PI-LL(OR: 3.8[1.4-9.8]). Clinically, patients undergoing combined approach demonstrated higher rates of meeting SCB in ODI by 2Y while minimizing rates of PJF, most often with an ALIF at L5-S1(ODI-SCB: OR: 1.4,[1.1-2.0];PJF: OR: 0.4,[0.2-0.8]).Conclusions
Among patients undergoing ASD realignment, optimal lumbar shape and proportion can be achieved more often with a combined approach. While TLIFs incorporating a three-column osteotomy at L3 and L4 can restore lordosis and normalize pelvic compensation, ALIFs at L5-S1 were most likely to achieve complex realignment goals with an added clinical benefit and mitigation of junctional failure.Item Open Access Establishment of an Individualized Distal Junctional Kyphosis Risk Index following the Surgical Treatment of Adult Cervical Deformities.(Spine, 2023-01) Passias, Peter G; Naessig, Sara; Sagoo, Navraj; Passfall, Lara; Ahmad, Waleed; Lafage, Renaud; Lafage, Virginie; Vira, Shaleen; Schoenfeld, Andrew J; Oh, Cheongeun; Protopsaltis, Themistocles; Kim, Han Jo; Daniels, Alan; Hart, Robert; Burton, Douglas; Klineberg, Eric O; Bess, Shay; Schwab, Frank; Shaffrey, Christopher; Ames, Christopher P; Smith, Justin S; International Spine Study GroupStudy design
A retrospective review of a multicenter comprehensive cervical deformity (CD) database.Objective
To develop a novel risk index specific to each patient to aid in patient counseling and surgical planning to minimize postop distal junctional kyphosis (DJK) occurrence.Background
DJK is a radiographic finding identified after patients undergo instrumented spinal fusions which can result in sagittal spinal deformity, pain and disability, and potentially neurological compromise. DJK is considered multifactorial in nature and there is a lack of consensus on the true etiology of DJK.Materials and methods
CD patients with baseline (BL) and at least one-year postoperative radiographic follow-up were included. A patient-specific DJK score was created through use of unstandardized Beta weights of a multivariate regression model predicting DJK (end of fusion construct to the second distal vertebra change in this angle by <-10° from BL to postop).Results
A total of 110 CD patients included (61 yr, 66.4% females, 28.8 kg/m 2 ). In all, 31.8% of these patients developed DJK (16.1% three males, 11.4% six males, 62.9% one-year). At BL, DJK patients were more frail and underwent combined approach more (both P <0.05). Multivariate model regression analysis identified individualized scores through creation of a DJK equation: -0.55+0.009 (BL inclination)-0.078 (preinflection)+5.9×10 -5 (BL lowest instrumented vertebra angle) + 0.43 (combine approach)-0.002 (BL TS-CL)-0.002 (BL pelvic tilt)-0.031 (BL C2 - C7) + 0.02 (∆T4-T12)+ 0.63 (osteoporosis)-0.03 (anterior approach)-0.036 (frail)-0.032 (3 column osteotomy). This equation has a 77.8% accuracy of predicting DJK. A score ≥81 predicted DJK with an accuracy of 89.3%. The BL reference equation correlated with two year outcomes of Numeric Rating Scales of Back percentage ( P =0.003), reoperation ( P =0.04), and minimal clinically importance differences for 5-dimension EuroQol questionnaire ( P =0.04).Conclusions
This study proposes a novel risk index of DJK development that focuses on potentially modifiable surgical factors as well as established patient-related and radiographic determinants. The reference model created demonstrated strong correlations with relevant two-year outcome measures, including axial pain-related symptoms, occurrence of related reoperations, and the achievement of minimal clinically importance differences for 5-dimension EuroQol questionnaire.Item Open Access Evolution of Adult Cervical Deformity Surgery Clinical and Radiographic Outcomes Based on a Multicenter Prospective Study: Are Behaviors and Outcomes Changing With Experience?(Spine, 2022-11) Passias, Peter G; Krol, Oscar; Moattari, Kevin; Williamson, Tyler K; Lafage, Virginie; Lafage, Renaud; Kim, Han Jo; Daniels, Alan; Diebo, Bassel; Protopsaltis, Themistocles; Mundis, Gregory; Kebaish, Khaled; Soroceanu, Alexandra; Scheer, Justin; Hamilton, D Kojo; Klineberg, Eric; Schoenfeld, Andrew J; Vira, Shaleen; Line, Breton; Hart, Robert; Burton, Douglas C; Schwab, Frank A; Shaffrey, Christopher; Bess, Shay; Smith, Justin S; Ames, Christopher P; International Spine Study GroupStudy design
Retrospective cohort study.Objective
Assess changes in outcomes and surgical approaches for adult cervical deformity surgery over time.Summary of background data
As the population ages and the prevalence of cervical deformity increases, corrective surgery has been increasingly seen as a viable treatment. Dramatic surgical advancements and expansion of knowledge on this procedure have transpired over the years, but the impact on cervical deformity surgery is unknown.Materials and methods
Adult cervical deformity patients (18 yrs and above) with complete baseline and up to the two-year health-related quality of life and radiographic data were included. Descriptive analysis included demographics, radiographic, and surgical details. Patients were grouped into early (2013-2014) and late (2015-2017) by date of surgery. Univariate and multivariable regression analyses were used to assess differences in surgical, radiographic, and clinical outcomes over time.Results
A total of 119 cervical deformity patients met the inclusion criteria. Early group consisted of 72 patients, and late group consisted of 47. The late group had a higher Charlson Comorbidity Index (1.3 vs. 0.72), more cerebrovascular disease (6% vs. 0%, both P <0.05), and no difference in age, frailty, deformity, or cervical rigidity. Controlling for baseline deformity and age, late group underwent fewer three-column osteotomies [odds ratio (OR)=0.18, 95% confidence interval (CI): 0.06-0.76, P =0.014]. At the last follow-up, late group had less patients with: a moderate/high Ames horizontal modifier (71.7% vs. 88.2%), and overcorrection in pelvic tilt (4.3% vs. 18.1%, both P <0.05). Controlling for baseline deformity, age, levels fused, and three-column osteotomies, late group experienced fewer adverse events (OR=0.15, 95% CI: 0.28-0.8, P =0.03), and neurological complications (OR=0.1, 95% CI: 0.012-0.87, P =0.03).Conclusion
Despite a population with greater comorbidity and associated risk, outcomes remained consistent between early and later time periods, indicating general improvements in care. The later cohort demonstrated fewer three-column osteotomies, less suboptimal realignments, and concomitant reductions in adverse events and neurological complications. This may suggest a greater facility with less invasive techniques.Item Open Access Factors Associated with the Maintenance of Cost-Effectiveness at 5 Years in Adult Spinal Deformity Corrective Surgery.(Spine, 2024-03) Passias, Peter G; Mir, Jamshaid M; Dave, Pooja; Smith, Justin S; Lafage, Renaud; Gum, Jeffrey; Line, Breton G; Diebo, Bassel; Daniels, Alan H; Hamilton, David Kojo; Buell, Thomas J; Scheer, Justin K; Eastlack, Robert K; Mullin, Jeffrey P; Mundis, Gregory M; Hosogane, Naobumi; Yagi, Mitsuru; Schoenfeld, Andrew J; Uribe, Juan S; Anand, Neel; Mummaneni, Praveen V; Chou, Dean; Klineberg, Eric O; Kebaish, Khaled M; Lewis, Stephen J; Gupta, Munish C; Kim, Han Jo; Hart, Robert A; Lenke, Lawrence G; Ames, Christopher P; Shaffrey, Christopher I; Schwab, Frank J; Lafage, Virginie; Hostin, Richard A; Bess, Shay; Burton, Douglas C; International Spine Study GroupStudy design
Retrospective cohort.Objective
To evaluate factors associated with the long-term durability of cost-effectiveness (CE) in ASD patients.Background
A substantial increase in costs associated with the surgical treatment for adult spinal deformity (ASD) has given precedence to scrutinize the value and utility it provides.Methods
We included 327 operative ASD patients with 5-year (5 Y) follow-up. Published methods were used to determine costs based on CMS.gov definitions and were based on the average DRG reimbursement rates. Utility was calculated using quality-adjusted life-years (QALY) utilizing the Oswestry Disability Index (ODI) converted to Short-Form Six-Dimension (SF-6D), with a 3% discount applied for its decline with life expectancy. The CE threshold of $150,000 was used for primary analysis.Results
Major and minor complication rates were 11% and 47% respectively, with 26% undergoing reoperation by 5 Y. The mean cost associated with surgery was $91,095±$47,003, with a utility gain of 0.091±0.086 at 1Y, QALY gained at 2 Y of 0.171±0.183, and at 5 Y of 0.42±0.43. The cost per QALY at 2 Y was $414,885, which decreased to $142,058 at 5 Y.With the threshold of $150,000 for CE, 19% met CE at 2 Y and 56% at 5 Y. In those in which revision was avoided, 87% met cumulative CE till life expectancy. Controlling analysis depicted higher baseline CCI and pelvic tilt (PT) to be the strongest predictors for not maintaining durable CE to 5 Y (CCI OR: 1.821 [1.159-2.862], P=0.009) (PT OR: 1.079 [1.007-1.155], P=0.030).Conclusions
Most patients achieved cost-effectiveness after four years postoperatively, with 56% meeting at five years postoperatively. When revision was avoided, 87% of patients met cumulative cost-effectiveness till life expectancy. Mechanical complications were predictive of failure to achieve cost-effectiveness at 2 Y, while comorbidity burden and medical complications were at 5 Y.Item Open Access Identifying Subsets of Patients With Adult Spinal Deformity Who Maintained a Positive Response to Nonoperative Management.(Neurosurgery, 2023-03) Passias, Peter G; Ahmad, Waleed; Tretiakov, Peter; Krol, Oscar; Segreto, Frank; Lafage, Renaud; Lafage, Virginie; Soroceanu, Alex; Daniels, Alan; Gum, Jeffrey; Line, Breton; Schoenfeld, Andrew J; Vira, Shaleen; Hart, Robert; Burton, Douglas; Smith, Justin S; Ames, Christopher P; Shaffrey, Christopher; Schwab, Frank; Bess, Shay; International Spine Study GroupBackground
Adult spinal deformity (ASD) represents a major cause of disability in the elderly population in the United States. Surgical intervention has been shown to reduce disability and pain in properly indicated patients. However, there is a small subset of patients in whom nonoperative treatment is also able to durably maintain or improve symptoms.Objective
To examine the factors associated with successful nonoperative management in patients with ASD.Methods
We retrospectively evaluated a cohort of 207 patients with nonoperative ASD, stratified into 3 groups: (1) success, (2) no change, and (3) failure. Success was defined as a gain in minimal clinically importance difference in both Oswestry Disability Index and Scoliosis Research Society-Pain. Logistic regression model and conditional inference decision trees established cutoffs for success according to baseline (BL) frailty and sagittal vertical axis.Results
In our cohort, 44.9% of patients experienced successful nonoperative treatment, 22.7% exhibited no change, and 32.4% failed. Successful nonoperative patients at BL were significantly younger, had a lower body mass index, decreased Charlson Comorbidity Index, lower frailty scores, lower rates of hypertension, obesity, depression, and neurological dysfunction (all P < .05) and significantly higher rates of grade 0 deformity for all Schwab modifiers (all P < .05). Conditional inference decision tree analysis determined that patients with a BL ASD-frailty index ≤ 1.579 (odds ratio: 8.3 [4.0-17.5], P < .001) were significantly more likely to achieve nonoperative success.Conclusion
Success of nonoperative treatment was more frequent among younger patients and those with less severe deformity and frailty at BL, with BL frailty the most important determinant factor. The factors presented here may be useful in informing preoperative discussion and clinical decision-making regarding treatment strategies.Item Open Access Improvements in Outcomes and Cost After Adult Spinal Deformity Corrective Surgery Between 2008 and 2019.(Spine, 2023-02) Passias, Peter G; Kummer, Nicholas; Imbo, Bailey; Lafage, Virginie; Lafage, Renaud; Smith, Justin S; Line, Breton; Vira, Shaleen; Schoenfeld, Andrew J; Gum, Jeffrey L; Daniels, Alan H; Klineberg, Eric O; Gupta, Munish C; Kebaish, Khaled M; Jain, Amit; Neuman, Brian J; Chou, Dean; Carreon, Leah Y; Hart, Robert A; Burton, Douglas C; Shaffrey, Christopher I; Ames, Christopher P; Schwab, Frank J; Hostin, Richard A; Bess, Shay; , on behalf of the International Spine Study GroupStudy design
A retrospective cohort study.Objective
To assess whether patient outcomes and cost-effectiveness of adult spinal deformity (ASD) surgery have improved over the past decade.Background
Surgery for ASD is an effective intervention, but one that is also associated with large initial healthcare expenditures. Changes in the cost profile for ASD surgery over the last decade has not been evaluated previously.Materials and methods
ASD patients who received surgery between 2008 and 2019 were included. Analysis of covariance was used to establish estimated marginal means for outcome measures [complication rates, reoperations, health-related quality of life, total cost, utility gained, quality adjusted life years (QALYs), cost-efficiency (cost per QALY)] by year of initial surgery. Cost was calculated using the PearlDiver database and represented national averages of Medicare reimbursement for services within a 30-day window including length of stay and death differentiated by complication/comorbidity, revision, and surgical approach. Internal cost data was based on individual patient diagnosis-related group codes, limiting revisions to those within two years (2Y) of the initial surgery. Cost per QALY over the course of 2008-2019 were then calculated.Results
There were 1236 patients included. There was an overall decrease in rates of any complication (0.78 vs . 0.61), any reoperation (0.25 vs . 0.10), and minor complication (0.54 vs . 0.37) between 2009 and 2018 (all P <0.05). National average 2Y cost decreased at an annual rate of $3194 ( R2 =0.6602), 2Y utility gained increased at an annual rate of 0.0041 ( R2 =0.57), 2Y QALYs gained increased annually by 0.008 ( R2 =0.57), and 2Y cost per QALY decreased per year by $39,953 ( R2 =0.6778).Conclusion
Between 2008 and 2019, rates of complications have decreased concurrently with improvements in patient reported outcomes, resulting in improved cost effectiveness according to national Medicare average and individual patient cost data. The value of ASD surgery has improved substantially over the course of the last decade.Item Open Access Patient-specific Cervical Deformity Corrections With Consideration of Associated Risk: Establishment of Risk Benefit Thresholds for Invasiveness Based on Deformity and Frailty Severity.(Clinical spine surgery, 2023-10) Passias, Peter G; Pierce, Katherine E; Williamson, Tyler K; Lebovic, Jordan; Schoenfeld, Andrew J; Lafage, Renaud; Lafage, Virginie; Gum, Jeffrey L; Eastlack, Robert; Kim, Han Jo; Klineberg, Eric O; Daniels, Alan H; Protopsaltis, Themistocles S; Mundis, Gregory M; Scheer, Justin K; Park, Paul; Chou, Dean; Line, Breton; Hart, Robert A; Burton, Douglas C; Bess, Shay; Schwab, Frank J; Shaffrey, Christopher I; Smith, Justin S; Ames, Christopher P; International Spine Study GroupStudy 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.Item Open Access Pelvic Nonresponse Following Treatment of Adult Spinal Deformity: Influence of Realignment Strategies on Occurrence.(Spine, 2023-05) Passias, Peter G; Pierce, Katherine E; Williamson, Tyler K; Krol, Oscar; Lafage, Renaud; Lafage, Virginie; Schoenfeld, Andrew J; Protopsaltis, Themistocles S; Vira, Shaleen; Line, Breton; Diebo, Bassel G; Ames, Christopher P; Kim, Han Jo; Smith, Justin S; Chou, Dean; Daniels, Alan H; Gum, Jeffrey L; Shaffrey, Christopher I; Burton, Douglas C; Kelly, Michael P; Klineberg, Eric O; Hart, Robert A; Bess, Shay; Schwab, Frank J; Gupta, Munish C; International Spine Study GroupPurpose
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.Item Open Access The Additional Economic Burden of Frailty in Adult Cervical Deformity Patients Undergoing Surgical Intervention.(Spine, 2022-10) Passias, Peter G; Kummer, Nicholas A; Williamson, Tyler K; Ahmad, Waleed; Lebovic, Jordan; Lafage, Virginie; Lafage, Renaud; Kim, Han Jo; Daniels, Alan H; Gum, Jeffrey L; Diebo, Bassel G; Gupta, Munish C; Soroceanu, Alexandra; Scheer, Justin K; Hamilton, D Kojo; Klineberg, Eric O; Line, Breton; Schoenfeld, Andrew J; Hart, Robert A; Burton, Douglas C; Eastlack, Robert K; Mundis, Gregory M; Mummaneni, Praveen; Chou, Dean; Park, Paul; Schwab, Frank J; Shaffrey, Christopher I; Bess, Shay; Ames, Christopher P; Smith, Justin S; International Spine Study GroupSummary of background data
The influence of frailty on economic burden following corrective surgery for the adult cervical deformity (CD) is understudied and may provide valuable insights for preoperative planning.Objective
To assess the influence of baseline frailty status on the economic burden of CD surgery.Study design
Retrospective cohort.Materials and methods
CD patients with frailty scores and baseline and two-year Neck Disability Index data were included. Frailty score was categorized patients by modified CD frailty index into not frail (NF) and frail (F). Analysis of covariance was used to estimate marginal means adjusting for age, sex, surgical approach, and baseline sacral slope, T1 slope minus cervical lordosis, C2-C7 angle, C2-C7 sagittal vertical axis. Costs were derived from PearlDiver registry data. Reimbursement consisted of a standardized estimate using regression analysis of Medicare payscales for services within a 30-day window including length of stay and death. This data is representative of the national average Medicare cost differentiated by complication/comorbidity outcome, surgical approach, and revision status. Cost per quality-adjusted life-year (QALY) at two years was calculated for NF and F patients.Results
There were 126 patients included. There were 68 NF patients and 58 classified as F. Frailty groups did not differ by overall complications, instance of distal junctional kyphosis, or reoperations (all P >0.05). These groups had similar rates of radiographic and clinical improvement by two years. NF and F had similar overall cost ($36,731.03 vs. $37,356.75, P =0.793), resulting in equivocal costs per QALYs for both patients at two years ($90,113.79 vs. $80,866.66, P =0.097).Conclusion
F and NF patients experienced similar complication rates and upfront costs, with equivocal utility gained, leading to comparative cost-effectiveness with NF patients based on cost per QALYs at two years. Surgical correction for CD is an economical healthcare investment for F patients when accounting for anticipated utility gained and cost-effectiveness following the procedure.Level of evidence
III.Item Open Access The impact of baseline cervical malalignment on the development of proximal junctional kyphosis following surgical correction of thoracolumbar adult spinal deformity.(Journal of neurosurgery. Spine, 2023-07) Passfall, Lara; Imbo, Bailey; Lafage, Virginie; Lafage, Renaud; Smith, Justin S; Line, Breton; Schoenfeld, Andrew J; Protopsaltis, Themistocles; Daniels, Alan H; Kebaish, Khaled M; Gum, Jeffrey L; Koller, Heiko; Hamilton, D Kojo; Hostin, Richard; Gupta, Munish; Anand, Neel; Ames, Christopher P; Hart, Robert; Burton, Douglas; Schwab, Frank J; Shaffrey, Christopher I; Klineberg, Eric O; Kim, Han Jo; Bess, Shay; Passias, Peter GObjective
The objective of this study was to identify the effect of baseline cervical deformity (CD) on proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) in patients with adult spinal deformity (ASD).Methods
This study was a retrospective analysis of a prospectively collected, multicenter database comprising ASD patients enrolled at 13 participating centers from 2009 to 2018. Included were ASD patients aged > 18 years with concurrent CD (C2-7 kyphosis < -15°, T1S minus cervical lordosis > 35°, C2-7 sagittal vertical axis > 4 cm, chin-brow vertical angle > 25°, McGregor's slope > 20°, or C2-T1 kyphosis > 15° across any three vertebrae) who underwent surgery. Patients were grouped according to four deformity classification schemes: Ames and Passias CD modifiers, sagittal morphotypes as described by Kim et al., and the head versus trunk balance system proposed by Mizutani et al. Mean comparison tests and multivariable binary logistic regression analyses were performed to assess the impact of these deformity classifications on PJK and PJF rates up to 3 years following surgery.Results
A total of 712 patients with concurrent ASD and CD met the inclusion criteria (mean age 61.7 years, 71% female, mean BMI 28.2 kg/m2, and mean Charlson Comorbidity Index 1.90) and underwent surgery (mean number of levels fused 10.1, mean estimated blood loss 1542 mL, and mean operative time 365 minutes; 70% underwent osteotomy). By approach, 59% of the patients underwent a posterior-only approach and 41% underwent a combined approach. Overall, 277 patients (39.1%) had PJK by 1 year postoperatively, and an additional 189 patients (26.7%) developed PJK by 3 years postoperatively. Overall, 65 patients (9.2%) had PJF by 3 years postoperatively. Patients classified as having a cervicothoracic deformity morphotype had higher rates of early PJK than flat neck deformity and cervicothoracic deformity patients (p = 0.020). Compared with the head-balanced patients, trunk-balanced patients had higher rates of PJK and PJF (both p < 0.05). Examining Ames modifier severity showed that patients with moderate and severe deformity by the horizontal gaze modifier had higher rates of PJK (p < 0.001).Conclusions
In patients with concurrent cervical and thoracolumbar deformities undergoing isolated thoracolumbar correction, the use of CD classifications allows for preoperative assessment of the potential for PJK and PJF that may aid in determining the correction of extending fusion levels.Item Open Access Three-Column Osteotomy in Adult Spinal Deformity: An Analysis of Temporal Trends in Usage and Outcomes.(The Journal of bone and joint surgery. American volume, 2022-11) Passias, Peter G; Krol, Oscar; Passfall, Lara; Lafage, Virginie; Lafage, Renaud; Smith, Justin S; Line, Breton; Vira, Shaleen; Daniels, Alan H; Diebo, Bassel; Schoenfeld, Andrew J; Gum, Jeffrey; Kebaish, Khaled; Than, Khoi; Kim, Han Jo; Hostin, Richard; Gupta, Munish; Eastlack, Robert; Burton, Douglas; Schwab, Frank J; Shaffrey, Christopher; Klineberg, Eric O; Bess, Shay; the International Spine Study GroupBackground
Three-column osteotomies (3COs), usually in the form of pedicle subtraction or vertebral column resection, have become common in adult spinal deformity surgery. Although a powerful tool for deformity correction, 3COs can increase the risks of perioperative morbidity.Methods
Operative patients with adult spinal deformity (Cobb angle of >20°, sagittal vertical axis [SVA] of >5 cm, pelvic tilt of >25°, and/or thoracic kyphosis of >60°) with available baseline and 2-year radiographic and health-related quality-of-life (HRQoL) data were included. Patients were stratified into 2 groups by surgical year: Group I (2008 to 2013) and Group II (2014 to 2018). Patients with 3COs were then isolated for outcomes analysis. Severe sagittal deformity was defined by an SVA of >9.5 cm. Best clinical outcome (BCO) was defined as an Oswestry Disability Index (ODI) of <15 and Scoliosis Research Society (SRS)-22 of >4.5. Multivariable regression analyses were used to assess differences in surgical, radiographic, and clinical parameters.Results
Seven hundred and fifty-two patients with adult spinal deformity met the inclusion criteria, and 138 patients underwent a 3CO. Controlling for baseline SVA, PI-LL (pelvic incidence minus lumbar lordosis), revision status, age, and Charlson Comorbidity Index (CCI), Group II was less likely than Group I to have a 3CO (21% versus 31%; odds ratio [OR] = 0.6; 95% confidence interval [CI] = 0.4 to 0.97) and more likely to have an anterior lumbar interbody fusion (ALIF; OR = 1.6; 95% CI = 1.3 to 2.3) and a lateral lumbar interbody fusion (LLIF; OR = 3.8; 95% CI = 2.3 to 6.2). Adjusted analyses showed that Group II had a higher likelihood of supplemental rod usage (OR = 21.8; 95% CI = 7.8 to 61) and a lower likelihood of proximal junctional failure (PJF; OR = 0.23; 95% CI = 0.07 to 0.76) and overall hardware complications by 2 years (OR = 0.28; 95% CI = 0.1 to 0.8). In an adjusted analysis, Group II had a higher likelihood of titanium rod usage (OR = 2.7; 95% CI = 1.03 to 7.2). Group II had a lower 2-year ODI and higher scores on Short Form (SF)-36 components and SRS-22 total (p < 0.05 for all). Controlling for baseline ODI, Group II was more likely to reach the BCO for the ODI (OR = 2.8; 95% CI = 1.2 to 6.4) and the SRS-22 total score (OR = 4.6; 95% CI = 1.3 to 16).Conclusions
Over a 10-year period, the rates of 3CO usage declined, including in cases of severe deformity, with an increase in the usage of PJF prophylaxis. A better understanding of the utility of 3CO, along with a greater implementation of preventive measures, has led to a decrease in complications and PJF and a significant improvement in patient-reported outcome measures.Level of evidence
Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.Item Open Access When Not to Operate in Spinal Deformity: Identifying Subsets of Patients with Simultaneous Clinical Deterioration, Major Complications, and Reoperation.(Spine, 2023-07) Passias, Peter G; Pierce, Katherine E; Dave, Pooja; Lafage, Renaud; Lafage, Virginie; Schoenfeld, Andrew J; Line, Breton; Uribe, Juan; Hostin, Richard; Daniels, Alan; Hart, Robert; Burton, Douglas; Kim, Han Jo; Mundis, Gregory M; Eastlack, Robert; Diebo, Bassel G; Gum, Jeffrey L; Shaffrey, Christopher; Schwab, Frank; Ames, Christopher P; Smith, Justin S; Bess, Shay; Klineberg, Eric; Gupta, Munish C; Hamilton, D Kojo; International Spine Study GroupStudy 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 pre-operative consideration and counseling.Methods
Patients >18yrs 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 2Y: (1) clinical: deteriorating in ODI at 2Y f/u (2) complications/reop: 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
633 ASD (59.9 years, 79%F, 27.7 kg/m2, CCI: 1.74) were included. Baseline severe Schwab modifier incidence (++): 39.2% PI-LL, 28.8% SVA, 28.9% PT. 15.5% of patients deteriorated in ODI by 2 years, while 7.6% underwent a 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), 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 DRAM 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 tends to occur in severely comorbid patients with major baseline psychological distress scores, poor neurologic function, and concomitant cervical malalignment.