Browsing by Author "Pierce, Katherine E"
Now showing 1 - 20 of 25
Results Per Page
Sort Options
Item Open Access Appropriate Risk Stratification and Accounting for Age-Adjusted Reciprocal Changes in the Thoracolumbar Spine Reduces the Incidence and Magnitude of Distal Junctional Kyphosis in Cervical Deformity Surgery.(Spine, 2021-11) Passias, Peter G; Bortz, Cole; Pierce, Katherine E; Kummer, Nicholas A; Lafage, Renaud; Diebo, Bassel G; Line, Breton G; Lafage, Virginie; Burton, Douglas C; Klineberg, Eric O; Kim, Han Jo; Daniels, Alan H; Mundis, Gregory M; Protopsaltis, Themistocles S; Eastlack, Robert K; Sciubba, Daniel M; Bess, Shay; Schwab, Frank J; Shaffrey, Christopher I; Smith, Justin S; Ames, Christopher P; International Spine Study Group (ISSG)Study design
Retrospective cohort study of a prospective cervical deformity (CD) database.Objective
Identify factors associated with distal junctional kyphosis (DJK); assess differences across DJK types.Summary of background data
DJK may develop as compensation for mal-correction of sagittal deformity in the thoracic curve. There is limited understanding of DJK drivers, especially for different DJK types.Methods
Included: patients with pre- and postoperative clinical/radiographic data. Excluded: patients with previous fusion to L5 or below. DJK was defined per surgeon note or DJK angle (kyphosis from LIV to LIV-2)<-10°, and pre- to postoperative change in DJK angle by<-10°. Age-specific target LL-TK alignment was calculated as published. Offset from target LL-TK was correlated to DJK magnitude and inclination. DJK types: severe (DJK<-20°), progressive (DJK increase>4.4°), symptomatic (reoperation or published disability thresholds of NDI ≥ 24 or mJOA≤14). Random forest identified factors associated with DJK. Means comparison tests assessed differences.Results
Included: 136 CD patients (61 ± 10 yr, 61%F). DJK rate was 30%. Postop offset from ideal LL-TK correlated with greater DJK angle (r = 0.428) and inclination of the distal end of the fusion construct (r = 0.244, both P < 0.02). Seven of the top 15 factors associated with DJK were radiographic, four surgical, and four clinical. Breakdown by type: severe (22%), progressive (24%), symptomatic (61%). Symptomatic had more posterior osteotomies than asymptomatic (P = 0.018). Severe had worse NDI and upper-cervical deformity (CL, C2 slope, C0-C2), as well as more posterior osteotomies than nonsevere (all P < 0.01). Progressive had greater malalignment both globally and in the cervical spine (all P < 0.03) than static. Each type had varying associated factors.Conclusion
Offset from age-specific alignment is associated with greater DJK and more anterior distal construct inclination, suggesting DJK may develop due to inappropriate realignment. Preoperative clinical and radiographic factors are associated with symptomatic and progressive DJK, suggesting the need for preoperative risk stratification.Level of Evidence: 3.Item Open Access At What Point Should the Thoracolumbar Region Be Addressed in Patients Undergoing Corrective Cervical Deformity Surgery?(Spine, 2021-10) Passias, Peter G; Pierce, Katherine E; Naessig, Sara; Ahmad, Waleed; Passfall, Lara; Lafage, Renaud; Lafage, Virginie; Kim, Han Jo; Daniels, Alan; Eastlack, Robert; Klineberg, Eric; Line, Breton; Mummaneni, Praveen; Hart, Robert; Burton, Douglas; Bess, Shay; Schwab, Frank; Shaffrey, Christopher; Smith, Justin S; Ames, Christopher P; International Spine Study GroupStudy design
Retrospective cohort study.Objective
The aim of this study was to investigate the impact of cervical to thoracolumbar ratios on poor outcomes in cervical deformity (CD) corrective surgery.Summary of background data
Consideration of distal regional and global alignment is a critical determinant of outcomes in CD surgery. For operative CD patients, it is unknown whether certain thoracolumbar parameters play a significant role in poor outcomes and whether addressing such parameters is warranted.Methods
Included: surgical CD patients (C2-C7 Cobb >10°, cervical lordosis [CL] >10°, C2-C7 sagittal vertical axis (cSVA) >4 cm, or chin-brow vertical angle >25°) with baseline and 1-year data. Patients were assessed for ratios of preop cervical and global parameters including: C2 Slope/T1 slope, T1 slope minus C2-C7 lordosis (TS-CL)/mismatch between pelvic incidence and lumbar lordosis (PI-LL), cSVA/sagittal vertical axis (SVA). Deformity classification ratios of cervical (Ames-ISSG) to spinopelvic (SRS-Schwab) were investigated: cSVA modifier/SVA modifier, TS-CL modifier/PI-LL modifier. Cervical to thoracic ratios included C2-C7 lordosis/T4-T12 kyphosis. Correlations assessed the relationship between ratios and poor outcomes (major complication, reoperation, distal junctional kyphosis (DJK), or failure to meet minimal clinically important difference [MCID]). Decision tree analysis through multiple iterations of multivariate regressions assessed cut-offs for ratios for acquiring suboptimal outcomes.Results
A total of 110 CD patients were included (61.5 years, 66% F, 28.8 kg/m2). Mean preoperative radiographic ratios calculated: C2 slope/T1 slope of 1.56, TS-CL/PI-LL of 11.1, cSVA/SVA of 5.4, CL/thoracic kyphosis (TK) of 0.26. Ames-ISSG and SRS-Schwab modifier ratios: cSVA/SVA of 0.1 and TS-CL/PI-LL of 0.35. Pearson correlations demonstrated a relationship between major complications and baseline TS-CL/PI-LL, Ames TS-CL/Schwab PI-LL modifiers, and the CL/TK ratios (P < 0.050). Reoperation had significant correlation with TS-CL/PI-LL and cSVA/SVA ratios. Postoperative DJK correlated with C2 slope/T1 slope and CL/TK ratios. Not meeting MCID for Neck Disability Index (NDI) correlated with CL/TK ratio and not meeting MCID for EQ5D correlated with Ames TS-CL/Schwab PI-LL.Conclusion
Consideration of cervical to global alignment is a critical determinant of outcomes in CD corrective surgery. Key ratios of cervical to global alignment correlate with suboptimal clinical outcomes. A larger cervical lordosis to TK predicted postoperative complication, DJK, and not meeting MCID for NDI.Level of Evidence: 4.Item Open Access Baseline Frailty Status Influences Recovery Patterns and Outcomes Following Alignment Correction of Cervical Deformity.(Neurosurgery, 2021-05) Pierce, Katherine E; Passias, Peter G; Daniels, Alan H; Lafage, Renaud; Ahmad, Waleed; Naessig, Sara; Lafage, Virginie; Protopsaltis, Themistocles; Eastlack, Robert; Hart, Robert; Burton, Douglas; Bess, Shay; Schwab, Frank; Shaffrey, Christopher; Smith, Justin S; Ames, ChristopherBackground
Frailty severity may be an important determinant for impaired recovery after cervical spine deformity (CD) corrective surgery.Objective
To evaluate postop clinical recovery among CD patients between frailty states undergoing primary procedures.Methods
Patients >18 yr old undergoing surgery for CD with health-related quality of life (HRQL) data at baseline, 3-mo, and 1-yr postoperative were identified. Patients were stratified by the modified CD frailty index scale from 0 to 1 (no frailty [NF] <0.3, mild/severe fraily [F] >0.3). Patients in NF and F groups were propensity score matched for TS-CL (T1 slope [TS] minus angle between the C2 inferior end plate and the C7 inferior end plate [CL]) to control for baseline deformity. Area under the curve was calculated for follow-up time intervals determining overall normalized, time-adjusted HRQL outcomes; Integrated Health State (IHS) was compared between NF and F groups.Results
A total of 106 CD patients were included (61.7 yr, 66% F, 27.7 kg/m2)-by frailty group: 52.8% NF, 47.2% F. After propensity score matching for TS-CL (mean: 38.1°), 38 patients remained in each of the NF and F groups. IHS-adjusted HRQL outcomes from baseline to 1 yr showed a significant difference in Euro-Qol 5 Dimension scores (NF: 1.02, F: 1.07, P = .016). No significant differences were found in the IHS Neck Disability Index (NDI) and modified Japanese Orthopedic Association between frailty groups (P > .05). F patients had more postop major complications (31.3%) compared to the NF (8.9%), P = .004, though DJK occurrence and reoperation between the groups was not significant.Conclusion
While all groups exhibited improved postop disability and pain scores, frail patients experienced greater amount of improvement in overall health state compared to baseline disability. This signifies that with frailty severity, patients have more room for improvement postop compared to baseline quality of life.Item Open Access Cervical deformity patients with baseline hyperlordosis or hyperkyphosis differ in surgical treatment and radiographic outcomes(Journal of Craniovertebral Junction and Spine, 2021-07-01) Alas, Haddy; Passias, Peter Gust; Diebo, Bassel G; Brown, Avery E; Pierce, Katherine E; Bortz, Cole; Lafage, Renaud; Ames, Christopher P; Line, Breton; Klineberg, Eric O; Burton, Douglas C; Uribe, Juan S; Kim, Han Jo; Daniels, Alan H; Bess, Shay; Protopsaltis, Themistocles; Mundis, Gregory M; Shaffrey, Christopher I; Schwab, Frank J; Smith, Justin S; Lafage, VirginieIntroduction: Patients with symptomatic cervical deformity (CD) requiring surgical correction often present with hyperkyphosis (HK), though patients with hyperlordotic curves may require surgery as well. Few studies have investigated differences in CD-corrective surgery with regards to HK and hyperlordosis (HL). Materials and Methods: Operative CD patients (C2-C7 Cobb >10°, cervical lordosis [CL] >10°, cervical sagittal vertical axis [cSVA] >4 cm, chin-brow vertical angle >25°) with baseline (BL) and 1Y radiographic data. Patients were stratified based on BL C2-7 lordosis (CL) angle: those >1 standard deviation (SD) from the mean (-6.96° ±21.47°) were hyperlordotic (>14.51°) or hyperkyphotic (≤28.43°) depending on directionality. Patients within 1 SD were considered the control group. Results: One hundred and two surgical CD pts (61 years, 65%F, 30 kg/m 2) with BL and 1Y radiographic data were included. Twenty pts met definitions for HK and 21 pts met definitions for HL. No differences in demographics or disability were noted. HK had higher estimated blood loss (EBL) with anterior approaches than HL but similar EBL with the posterior approach. Op-time did not differ between groups. Control, HL, and HK groups differed in BL TS-CL (36.6° vs. 22.5° vs. 60.7°, P < 0.001) and BL-sagittal vertical axis (SVA) (10.8 vs. 7.0 vs. -47.8 mm, P = 0.001). HL pts had less discectomies, less corpectomies, and similar osteotomy rates to HK. HL had × 3 revisions of HK and controls (28.6 vs. 10.0 vs. 9.2%, respectively, P = 0.046). At 1Y, HL pts had higher cSVA, and trended higher SVA and SS than HK. In terms of BL-upper cervical alignment, HK pts had higher McGregor's-slope (16.1° vs. -3.3°, P = 0.001) and C0-C2 Cobb (43.3° vs. 26.9°, P < 0.001), however postoperative differences in McGregor's slope and C0-C2 were not significant. HK drivers of deformity were primarily C (90%), whereas HL had primary computed tomography (38.1%), upper thoracic (23.8%), and C (14.3%) drivers. Conclusions: Hyperlodotic patients trended higher revision rates with greater radiographic malalignment at 1Y postoperative, perhaps due to undercorrection compared to kyphotic etiologies.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 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 a Novel Cervical Deformity Surgical Invasiveness Index.(Spine, 2020-01) Passias, Peter G; Horn, Samantha R; Soroceanu, Alexandra; Oh, Cheongeun; Ailon, Tamir; Neuman, Brian J; Lafage, Virginie; Lafage, Renaud; Smith, Justin S; Line, Breton; Bortz, Cole A; Segreto, Frank A; Brown, Avery; Alas, Haddy; Pierce, Katherine E; Eastlack, Robert K; Sciubba, Daniel M; Protopsaltis, Themistocles S; Klineberg, Eric O; Burton, Douglas C; Hart, Robert A; Schwab, Frank J; Bess, Shay; Shaffrey, Christopher I; Ames, Christopher P; International Spine Study GroupSTUDY DESIGN:Retrospective review. OBJECTIVE:The aim of this study was to develop a novel surgical invasiveness index for cervical deformity (CD) surgery that incorporates CD-specific parameters. SUMMARY OF BACKGROUND DATA:There has been a surgical invasiveness index for general spine surgery and adult spinal deformity, but a CD index has not been developed. METHODS:CD was defined as at least one of the following: C2-C7 Cobb >10°, cervical lordosis (CL) >10°, cervical sagittal vertical axis (cSVA) >4 cm, chin brow vertical angle >25°. Consensus from experienced spine and neurosurgeons selected weightings for each variable that went into the invasiveness index. Binary logistic regression predicted high operative time (>338 minutes), estimated blood loss (EBL) (>600 mL), or length of stay (LOS) >5 days) based on the median values of operative time, EBL, and LOS. Multivariable regression modeling was utilized to construct a final model incorporating the strongest combination of factors to predict operative time, LOS, and EBL. RESULTS:Eighty-five CD patients were included (61 years, 66% females). The variables in the newly developed CD invasiveness index with their corresponding weightings were: history of previous cervical surgery (3), anterior cervical discectomy and fusion (2/level), corpectomy (4/level), levels fused (1/level), implants (1/level), posterior decompression (2/level), Smith-Peterson osteotomy (2/level), three-column osteotomy (8/level), fusion to upper cervical spine (2), absolute change in T1 slope minus cervical lordosis, cSVA, T4-T12 thoracic kyphosis (TK), and sagittal vertical axis (SVA) from baseline to 1-year. The newly developed CD-specific invasiveness index strongly predicted long LOS (R = 0.310, P < 0.001), high EBL (R = 0.170, P = 0.011), and extended operative time (R = 0.207, P = 0.031). A second analysis used multivariable regression modeling to determine which combination of factors in the newly developed index were the strongest determinants of operative time, LOS, and EBL. The final predictive model included: number of corpectomies, levels fused, decompression, combined approach, and absolute changes in SVA, cSVA, and TK. This model predicted EBL (R = 0.26), operative time (R = 0.12), and LOS (R = 0.13). CONCLUSION:Extended LOS, operative time, and high blood loss were strongly predicted by the newly developed CD invasiveness index, incorporating surgical factors and radiographic parameters clinically relevant for patients undergoing CD corrective surgery. LEVEL OF EVIDENCE:4.Item Open Access Does Patient Frailty Status Influence Recovery Following Spinal Fusion for Adult Spinal Deformity?: An Analysis of Patients With 3-Year Follow-up.(Spine, 2020-04) Pierce, Katherine E; Passias, Peter G; Alas, Haddy; Brown, Avery E; Bortz, Cole A; Lafage, Renaud; Lafage, Virginie; Ames, Christopher; Burton, Douglas C; Hart, Robert; Hamilton, Kojo; Kelly, Michael; Hostin, Richard; Bess, Shay; Klineberg, Eric; Line, Breton; Shaffrey, Christopher; Mummaneni, Praveen; Smith, Justin S; Schwab, Frank A; International Spine Study Group (ISSG)Study design
Retrospective review of a prospective database.Objective
The aim of this study was to evaluate postop clinical recovery among adult spinal deformity (ASD) patients between frailty states undergoing primary procedures SUMMARY OF BACKGROUND DATA.: Frailty severity may be an important determinant for impaired recovery after corrective surgery.Methods
It included ASD patients with health-related quality of life (HRQLs) at baseline (BL), 1 year (1Y), and 3 years (3Y). Patients stratified by frailty by ASD-frailty index scale 0-1(no frailty: <0.3 [NF], mild: 0.3-0.5 [MF], severe: >0.5 [SF]). Demographics, alignment, and SRS-Schwab modifiers were assessed with χ/paired t tests to compare HRQLs: Scoliosis Research Society 22-question Questionnaire (SRS-22), Numeric Rating Scale (NRS) Back/Leg Pain, Oswestry Disability Index (ODI). Area-under-the-curve (AUC) method generated normalized HRQL scores at baseline (BL) and f/u intervals (1Y, 3Y). AUC was calculated for each f/u, and total area was divided by cumulative f/u, generating one number describing recovery (Integrated Health State [IHS]).Results
A total of 191 patients were included (59 years, 80% females). Breakdown of patients by frailty status: 43.6% NF, 40.8% MF, 15.6% SF. SF patients were older (P = 0.003), >body mass index (P = 0.002). MF and SF were significantly (P < 0.001) more malaligned at BL: pelvic tilt (NF: 21.6°; MF: 27.3°; SF: 22.1°), pelvic incidence and lumbar lordosis (7.4°, 21.2°, 19.7°), sagittal vertical axis (31 mm, 87 mm, 82 mm). By SRS-Schwab, NF were mostly minor (40%), and MF and SF markedly deformed (64%, 57%). Frailty groups exhibited BL to 3Y improvement in SRS-22, ODI, NRS Back/Leg (P < 0.001). After HRQL normalization, SF had improvement in SRS-22 at year 1 and year 3 (P < 0.001), and NRS Back at 1Y. 3Y IHS showed a significant difference in SRS-22 (NF: 1.2 vs. MF: 1.32 vs. SF: 1.69, P < 0.001) and NRS Back Pain (NF: 0.52, MF: 0.66, SF: 0.6, P = 0.025) between frailty groups. SF had more complications (79%). SF/marked deformity had larger invasiveness score (112) compared to MF/moderate deformity (86.2). Controlling for baseline deformity and invasiveness, SF showed more improvement in SRS-22 IHS (NF: 1.21, MF: 1.32, SF: 1.66, P < 0.001).Conclusion
Although all frailty groups exhibited improved postop disability/pain scores, SF patients recovered better in SRS-22 and NRS Back. Despite SF patients having more complications and larger invasiveness scores, they had overall better patient-reported outcomes, signifying that with frailty severity, patients have more room for improvement postop compared to BL quality of life.Level of evidence
3.Item Open Access Effect of age-Adjusted alignment goals and distal inclination angle on the fate of distal junctional kyphosis in cervical deformity surgery(Journal of Craniovertebral Junction and Spine, 2021-01-01) Passias, Peter Gust; Horn, Samantha R; Lafage, Virginie; Lafage, Renaud; Smith, Justin S; Line, Breton G; Protopsaltis, Themistocles S; Soroceanu, Alex; Bortz, Cole; Segreto, Frank A; Ahmad, Waleed; Naessig, Sara; Pierce, Katherine E; Brown, Avery E; Alas, Haddy; Kim, Han Jo; Daniels, Alan H; Klineberg, Eric O; Burton, Douglas C; Hart, Robert A; Schwab, Frank J; Bess, Shay; Shaffrey, Christopher I; Ames, Christopher P; International Spine Study GroupBackground: Age-Adjusted alignment targets in the context of distal junctional kyphosis (DJK) development have yet to be investigated. Our aim was to assess age-Adjusted alignment targets, reciprocal changes, and role of lowest instrumented level orientation in DJK development in cervical deformity (CD) patients. Methods: CD patients were evaluated based on lowest fused level: cervical (C7 or above), upper thoracic (UT: T1-T6), and lower thoracic (LT: T7-T12). Age-Adjusted alignment targets were calculated using published formulas for sagittal vertical axis (SVA), pelvic incidence-lumbar lordosis (PI-LL), pelvic tilt (PT), T1 pelvic angle (TPA), and LL-Thoracic kyphosis (TK). Outcome measures were cervical and global alignment parameters: Cervical SVA (cSVA), cervical lordosis, C2 slope, C2-T3 angle, C2-T3 SVA, TS-CL, PI-LL, PT, and SVA. Subanalysis matched baseline PI to assess age-Adjusted alignment between DJK and non-DJK. Results: Seventy-six CD patients included. By 1Y, 20 patients developed DJK. Non-DJK patients had 27% cervical lowest instrumented vertebra (LIV), 68% UT, and 5% LT. DJK patients had 25% cervical, 50% UT, and 25% LT. There were no baseline or 1Y differences for PI, PI-LL, SVA, TPA, or PT for actual and age-Adjusted targets. DJK patients had worse baseline cSVA and more severe 1Y cSVA, C2-T3 SVA, and C2 slope (P < 0.05). The distribution of over/under corrected patients and the offset between actual and ideal alignment for SVA, PT, TPA, PI-LL, and LL-TK were similar between DJK and non-DJK patients. DJK patients requiring reoperation had worse postoperative changes in all cervical parameters and trended toward larger offsets for global parameters. Conclusion: CD patients with severe baseline malalignment went on to develop postoperative DJK. Age-Adjusted alignment targets did not capture differences in these populations, suggesting the need for cervical-specific goals.Item Open Access Limited morbidity and possible radiographic benefit of C2 vs. subaxial cervical upper-most instrumented vertebrae(Journal of Spine Surgery, 2019-06-29) Passias, Peter G; Bortz, Cole A; Segreto, Frank; Horn, Samantha; Pierce, Katherine E; Alas, Haddy; Brown, Avery E; Lafage, Renaud; Lafage, Virginie; Smith, Justin S; Line, Breton; Eastlack, Robert; Sciubba, Daniel M; Klineberg, Eric O; Soroceanu, Alexandra; Burton, Douglas C; Schwab, Frank J; Bess, Shay; Shaffrey, Christopher I; Ames, Christopher PBackground: The study aims to evaluate differences in alignment and clinical outcomes between surgical cervical deformity (CD) patients with a subaxial upper-most instrumented vertebra (UIV) and patients with a UIV at C2. Use of CD-corrective instrumentation in the subaxial cervical spine is considered risky due to narrow subaxial pedicles and vertebral artery anatomy. While C2 fixation provides increased stability, the literature lacks guidelines indicating extension of CD-corrective fusion from the subaxial spine to C2. Methods: Included: operative CD patients with baseline (BL) and 1-year postop (1Y) radiographic data, cervical UIV ≥ C2. Patients were grouped by UIV: C2 or subaxial (C3-C7) and propensity score matched (PSM) for BL cSVA. Mean comparison tests assessed differences in BL and 1Y patient-related, radiographic, and surgical data between UIV groups, and BL-1Y changes in alignment and clinical outcomes. Results: Following PSM, 31 C2 UIV and 31 subaxial UIV patients undergoing CD-corrective surgery were included. Groups did not differ in BL comorbidity burden (P=0.175) or cSVA (P=0.401). C2 patients were older (64 vs. 58 yrs, P=0.010) and had longer fusions (9 vs. 6 levels, P=0.002). Overall, patients showed BL-1Y improvements in TS-CL (P<0.001), cSVA (P=0.005), McGS (P=0.004). Cervical flexibility was maintained at 1Y regardless of UIV, assessed by CL flexion (−0.2° vs. 6.0°, P=0.115) and extension (13.9° vs. 9.9°, P=0.366). While both subaxial and C2 patients showed BL-1Y improvements in McGS (both P<0.030), C2 patients improved to a larger degree (7.3° vs. 6.2°). Between UIV groups, there were no differences in BL-1Y changes in HRQLs, overall complication rates, or operative complication rates (all P>0.05). Conclusions: C2 UIV patients showed similar cervical range of motion and baseline to 1-year functional outcomes as patients with a subaxial UIV. C2 UIV patients also showed greater baseline to 1-year horizontal gaze improvement and had complication profiles similar to subaxial UIV patients, demonstrating the radiographic benefit and minimal functional loss associated with extending fusion constructs to C2. In the treatment of adult cervical deformities, extension of the reconstruction construct to the axis may allow for certain clinical benefits with less morbidity than previously acknowledged.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 Predicting extended operative time and length of inpatient stay in cervical deformity corrective surgery.(Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia, 2019-11) Horn, Samantha R; Passias, Peter G; Bortz, Cole A; Pierce, Katherine E; Lafage, Virginie; Lafage, Renaud; Brown, Avery E; Alas, Haddy; Smith, Justin S; Line, Breton; Deviren, Vedat; Mundis, Gregory M; Kelly, Michael P; Kim, Han Jo; Protopsaltis, Themistocles; Daniels, Alan H; Klineberg, Eric O; Burton, Douglas C; Hart, Robert A; Schwab, Frank J; Bess, Shay; Shaffrey, Christopher I; Ames, Christopher P; International Spine Study GroupIt's increasingly common for surgeons to operate on more challenging cases and higher risk patients, resulting in longer op-time and inpatient LOS. Factors predicting extended op-time and LOS for cervical deformity (CD) patients are understudied. This study identified predictors of extended op-time and length of stay (LOS) after CD-corrective surgery. CD patients with baseline (BL) radiographic data were included. Patients were stratified by extended LOS (ELOS; >75th percentile) and normal LOS (N-LOS; <75th percentile). Op-time analysis excluded staged cases, cases >12 h. A Conditional Variable Importance Table used non-replacement sampling set of Conditional Inference trees to identify influential factors. Mean comparison tests compared LOS and op-time for top factors. 142 surgical CD patients (61 yrs, 62%F, 8.2 levels fused). Op-time and LOS were 358 min and 7.2 days; 30% of patients experienced E-LOS (14 ± 13 days). Overlapping predictors of E-LOS and op-time included levels fused (>7 increased LOS 2.7 days; >5 increased op-time 96 min, P < 0.001), approach (anterior reduced LOS 3.0 days; combined increased op-time 69 min, P < 0.01), BMI (>38 kg/m2 increased LOS 8.1 days; >39 kg/m2 increased op-time 17 min), and osteotomy (LOS 2.0 days, op-time 62 min, P < 0.005). BL cervical parameters increased LOS and op-time: cSVA (>42 mm increased LOS; >50 mm increased op-time, P < 0.030), C0 slope (>@-0.9° increased LOS, >0.3° increased op-time, P < 0.003.) Additional op-time predictors: prior cervical surgery (p = 0.004) and comorbidities (P = 0.015). Other predictors of E-LOS: EBL (P < 0.001), change in mental status (P = 0.001). Baseline cervical malalignment, levels fused, and osteotomy predicted both increased op-time and LOS. These results can be used to better optimize patient care, hospital efficiency, and resource allocation.Item Open Access Predictors of serious, preventable, and costly medical complications in a population of adult spinal deformity patients.(The spine journal : official journal of the North American Spine Society, 2021-09) Alas, Haddy; Passias, Peter G; Brown, Avery E; Pierce, Katherine E; Bortz, Cole; Bess, Shay; Lafage, Renaud; Lafage, Virginie; Ames, Christopher P; Burton, Douglas C; Hamilton, D Kojo; Kelly, Michael P; Hostin, Richard; Neuman, Brian J; Line, Breton G; Shaffrey, Christopher I; Smith, Justin S; Schwab, Frank J; Klineberg, Eric O; International Spine Study GroupBackground context
In 2008, the Centers for Medicare and Medicaid Services (CMS) established a list of hospital-acquired conditions (HACs) with significant deleterious effects on both patients and providers. Adult spinal deformity (ASD) surgery is complex and highly invasive, and as such may result in significant morbidity including these HACs.Purpose
Identify predictors for developing the most common HACs among adult spinal deformity (ASD) patients undergoing corrective surgery.Study design/setting
Retrospective analysis.Patient sample
One thousand one hundred and seventy-one ASD patients.Outcome measures
HACs, Health-Related Quality of Life scores(HRQLs), Reoperation, Integrated Health State (IHS) METHODS: ASD pts undergoing surgery (>18 years, scoliosis ≥20°, SVA ≥5 cm, PT ≥25° and/or TK >60°) with complete data at BL and up to 2 years post-op were included. Patients were stratified by presence of >1 HAC, defined as at least one superficial/deep SSI, UTI, DVT, or PE within a 30-day post-op window. Random forest analysis generated 5,000 Conditional Inference Trees to compute a variable importance table for top predictors of HACs. An area-under-the-curve (AUC) methodology compared normalized HRQL scores between groups to determine an IHS with 2-year follow-up.Results
Total of 1,171 pts (59.8 years, 76.2%F, 28.1kg/m2) underwent corrective ASD surgery, with 1,053 pts in the non-HAC group and 118 in the HAC group. Of these pts, 25.4% had UTI, 15.4% DVT, 19.2% superficial SSI, 20.8% deep SSI, and 19.2% PE. HAC pts were on average older (63.5 vs 59.3, p=.004) and more often frail (51.3 vs 39.7%, p=.021) than non-HAC pts. Postop LOS and reoperation were most associated with HAC groups: [1] LOS >7 days [2] reoperation. Patient-related predictors of HACs were [3] age >50 yerr, [4] frailty, and [13] BMI >31. Procedure-related predictors of HACs were [5] operative-time >405 minutes, [6] levels fused >9, EBL >1450 mL, and [11] decompression. BL radiographic predictors were [7] PT >20°, [9] PI-LL>6°, [10] TL Cobb angle >15°, [12] SVA C7-S1 >29 mm. No differences were observed between groups with regards to IHS ODI (0.73 vs 0.74, p=.863), SRS (1.3 vs1.3, p=.374), NRS Back (0.6 vs 0.6, p=.158). HAC had higher rates of reoperation than non-HAC (0.08 vs 0.01, p=.066), and any HAC within 30-days of index was a significant predictor of reoperation (OR: 2.448 [1.94-3.09], p<.001).Conclusions
In a population of ASD patients, HACs were associated with length of stay, reoperation, age, and frailty. Radiographic parameters such as pelvic tilt >20°, PI-LL >6°, & SVA >29 mm also increased odds of HACs, and should raise postoperative awareness for HAC development.Item Open Access Predictors of Superior Recovery Kinetics in Adult Cervical Deformity Correction: An Analysis Using a Novel Area Under the Curve Methodology.(Spine, 2021-05) Pierce, Katherine E; Passias, Peter G; Brown, Avery E; Bortz, Cole A; Alas, Haddy; Lafage, Renaud; Lafage, Virginie; Ames, Christopher; Burton, Douglas C; Hart, Robert; Hamilton, Kojo; Gum, Jeffrey; Scheer, Justin; Daniels, Alan; Bess, Shay; Soroceanu, Alex; Klineberg, Eric; Shaffrey, Christopher; Line, Breton; Schwab, Frank A; Smith, Justin S; on behalf of the International Spine Study Group (ISSG)Study design
Retrospective review of a prospective database.Objective
The aim of this study was to identify demographic, surgical, and radiographic factors that predict superior recovery kinetics following cervical deformity (CD) corrective surgery.Summary of background data
Analyses of CD corrective surgery use area under the curve (AUC) to assess health-related quality of life (HRQL) metrics throughout recovery.Methods
Outcome measures were baseline (BL) to 1-year (1Y) health-related quality of life (HRQL) (Neck Disability Index [NDI]). CD criteria were C2-7 Cobb angle >10°, coronal Cobb angle >10°, C2-C7 sagittal vertical axis (cSVA) >4 cm, TS-CL >10°, or chin-brow vertical angle >25°. AUC normalization divided BL and postoperative outcomes by BL. Normalized scores (y axis) were plotted against follow-up (x axis). AUC was calculated and divided by cumulative follow-up length to determine overall, time-adjusted recovery (Integrated Health State [IHS]). IHS NDI was stratified by quartile, uppermost 25% being "Superior" Recovery Kinetics (SRK) versus "Normal" Recovery Kinetics (NRK). BL demographic, clinical, and surgical information predicted SRK using generalized linear modeling.Results
Ninety-eight patients included (62 ± 10 years, 28 ± 6 kg/m2, 65% females, Charlson Comorbidity Index: 0.95), 6% smokers, 31% smoking history. Surgical approach was: combined (33%), posterior (49%), anterior (18%). Posterior levels fused: 8.7, anterior: 3.6, estimated blood loss: 915.9ccs, operative time: 495 minutes. Ames BL classification: cSVA (53.2% minor deformity, 46.8% moderate), TS-CL (9.8% minor, 4.3% moderate, 85.9% marked), horizontal gaze (27.4% minor, 46.6% moderate, 26% marked). Relative to BL NDI (Mean: 47), normalized NDI decreased at 3 months (0.9 ± 0.5, P = 0.260) and 1Y (0.78 ± 0.41, P < 0.001). NDI IHS correlated with age (P = 0.011), sex (P = 0.042), anterior approach (P = 0.042), posterior approach (P = 0.042). Greater BL pelvic tilt (PT) (SRK: 25.6°, NRK: 17°, P = 0.002), pelvic incidence-lumbar lordosis (PI-LL) (SRK: 8.4°, NRK: -2.8°, P = 0.009), and anterior approach (SRK: 34.8%, NRK: 13.3%; P = 0.020) correlated with SRK. 69.4% met MCID for NDI (<Δ-15) and 63.3% met substantial clinical benefit for NDI (<Δ-10); 100% of SRK met both MCID and substantial clinical benefit. The predictive model for SRK included (AUC = 88.1%): BL visual analog scale (VAS) EuroQol five-dimensional descriptive system (EQ5D) (odds rario [OR] 0.96, 95% confidence interval [CI]: 0.92-0.99), BL swallow sleep score (OR: 1.04, 95% CI: 1.01-1.06), BL PT (OR: 1.12, 95% CI: 1.03-1.22), BL modified Japanese Orthopedic Association scale (mJOA) (OR: 1.5, 95% CI: 1.07-2.16), BL T4-T12, BL T10-L2, BL T12-S1, and BL L1-S1.Conclusion
Superior recovery kinetics following CD surgery was predicted with high accuracy using BL patient-reported (VAS EQ5D, swallow sleep, mJOA) and radiographic factors (PT, TK, T10-L2, T12-S1, L1-S1). Awareness of these factors can improve decision-making and reduce postoperative neck disability.Level of Evidence: 3.Item Open Access Prioritization of Realignment Associated With Superior Clinical Outcomes for Cervical Deformity Patients.(Neurospine, 2021-09) Pierce, Katherine E; Passias, Peter G; Brown, Avery E; Bortz, Cole A; Alas, Haddy; Passfall, Lara; Krol, Oscar; Kummer, Nicholas; Lafage, Renaud; Chou, Dean; Burton, Douglas C; Line, Breton; Klineberg, Eric; Hart, Robert; Gum, Jeffrey; Daniels, Alan; Hamilton, Kojo; Bess, Shay; Protopsaltis, Themistocles; Shaffrey, Christopher; Schwab, Frank A; Smith, Justin S; Lafage, Virginie; Ames, Christopher; International Spine Study Group (ISSG)Objective
To prioritize the cervical parameter targets for alignment.Methods
Included: cervical deformity (CD) patients (C2-7 Cobb angle > 10°, cervical lordosis > 10°, cervical sagittal vertical axis [cSVA] > 4 cm, or chin-brow vertical angle > 25°) with full baseline (BL) and 1-year (1Y) radiographic parameters and Neck Disability Index (NDI) scores; patients with cervical [C] or cervicothoracic [CT] Primary Driver Ames type. Patients with BL Ames classified as low CD for both parameters of cSVA ( < 4 cm) and T1 slope minus cervical lordosis (TS-CL) ( < 15°) were excluded. Patients assessed: meeting minimum clinically important differences (MCID) for NDI ( < -15 ΔNDI). Ratios of correction were found for regional parameters categorized by primary Ames driver (C or CT). Decision tree analysis assessed cutoffs for differences associated with meeting NDI MCID at 1Y.Results
Seventy-seven CD patients (mean age, 62.1 years; 64% female; body mass index, 28.8 kg/m2). Forty-one point six percent of patients met MCID for NDI. A backwards linear regression model including radiographic differences as predictors from BL to 1Y for meeting MCID for NDI demonstrated an R2 of 0.820 (p = 0.032) included TS-CL, cSVA, McGregor's slope (MGS), C2 sacral slope, C2-T3 angle, C2-T3 SVA, cervical lordosis. By primary Ames driver, 67.5% of patients were C, and 32.5% CT. Ratios of change in predictors for MCID NDI patients for C and CT were not significant between the 2 groups (p > 0.050). Decision tree analysis determined cutoffs for radiographic change, prioritizing in the following order: ≥ 42.5° C2-T3 angle, > 35.4° cervical lordosis, < -31.76° C2 slope, < -11.57-mm cSVA, < -2.16° MGS, > -30.8-mm C2-T3 SVA, and ≤ -33.6° TS-CL.Conclusion
Certain ratios of correction of cervical parameters contribute to improving neck disability. Prioritizing these radiographic alignment parameters may help optimize patient-reported outcomes for patients undergoing CD surgery.Item Open Access Prioritization of realignment associated with superior clinical outcomes for surgical cervical deformity patients.(Journal of craniovertebral junction & spine, 2021-07) Pierce, Katherine E; Passias, Peter Gust; Brown, Avery E; Bortz, Cole A; Alas, Haddy; Lafage, Renaud; Krol, Oscar; Chou, Dean; Burton, Douglas C; Line, Breton; Klineberg, Eric; Hart, Robert; Gum, Jeffrey; Daniels, Alan; Hamilton, Kojo; Bess, Shay; Protopsaltis, Themistocles; Shaffrey, Christopher; Schwab, Frank A; Smith, Justin S; Lafage, Virginie; Ames, Christopher; International Spine Study GroupBackground
To optimize quality of life in patients with cervical deformity (CD), there may be alignment targets to be prioritized.Objective
To prioritize the cervical parameter targets for alignment.Methods
Included: CD patients (C2-C7 Cobb >10°°, C2-C7 lordosis [CL] >10°°, cSVA > 4 cm, or chin-brow vertical angle >25°°) with full baseline (BL) and 1-year (1Y) radiographic parameters and Neck Disability Index (NDI) scores; patients with cervical (C) or cervicothoracic (CT) Primary Driver Ames type. Patients with BL Ames classified as low CD for both parameters of cSVA (<4 cm) and T1 slope minus CL (TS-CL) (<15°°) were excluded. Patients assessed: Meeting Minimal Clinically Important Difference (MCID) for NDI (<-15 ΔNDI). Ratios of correction were found for regional parameters categorized by Primary Ames Driver (C or CT). Decision tree analysis assessed cut-offs for differences associated with meeting NDI MCID at 1Y.Results
Seventy-seven CD patients (62.1 years, 64%F, 28.8 kg/m2). 41.6% met MCID for NDI. A backward linear regression model including radiographic differences as predictors from BL to 1Y for meeting MCID for NDI demonstrated an R 2= 0.820 (P = 0.032) included TS-CL, cSVA, MGS, C2SS, C2-T3 angle, C2-T3 sagittal vertical axis (SVA), CL. By primary Ames driver, 67.5% of patients were C, and 32.5% CT. Ratios of change in predictors for MCID NDI patients for C and CT were not significant between the two groups (P > 0.050). Decision tree analysis determined cut-offs for radiographic change, prioritizing in the following order: ≥42.5° C2-T3 angle, >35.4° CL, <-31.76° C2 slope, <-11.57 mm cSVA, <-2.16° MGS, >-30.8 mm C2-T3 SVA, and ≤-33.6° TS-CL.Conclusions
Certain ratios of correction of cervical parameters contribute to improving neck disability. Prioritizing these radiographic alignment parameters may help optimize patient-reported outcomes for patients undergoing CD surgery.Item Open Access Probability of severe frailty development among operative and nonoperative adult spinal deformity patients: an actuarial survivorship analysis over a 3-year period.(The spine journal : official journal of the North American Spine Society, 2020-08) Passias, Peter G; Segreto, Frank A; Bortz, Cole A; Horn, Samantha R; Pierce, Katherine E; Naessig, Sara; Brown, Avery E; Jackson-Fowl, Brendan; Ahmad, Waleed; Oh, Cheongeun; Lafage, Virginie; Lafage, Renaud; Smith, Justin S; Daniels, Alan H; Line, Breton G; Kim, Han Jo; Uribe, Juan S; Eastlack, Robert K; Hamilton, D Kojo; Klineberg, Eric O; Burton, Douglas C; Hart, Robert AA; Schwab, Frank J; Shaffrey, Christopher I; Ames, Christopher P; Bess, Shay; International Spine Study GroupBackground
Little is known of how frailty, a dynamic measure of physiological age, progresses relative to age or disability status. Operative treatment of adult spinal deformity (ASD) may play a role in frailty remediation and maintenance.Purpose
Compare frailty status, severe frailty development, and factors influencing severe frailty development among ASD patients undergoing operative or nonoperative treatment.Design
Retrospective review with maximum follow-up of 3 years.Setting
Prospective, multicenter, ASD database.Participants
Patients were consecutively enrolled from 13 participating centers.Inclusion criteria
≥18 years undergoing either operative or nonoperative treatment for ASD, exclusion criteria: spinal deformity of neuromuscular etiology, presence of active infection, or malignancy. The mean age of the participants analyzed were 54.9 for the operative cohort and 55.0 for the nonoperative cohort.Outcomes measures
Frailty status, severe frailty development, and factors influencing severe frailty development.Methods
ASD patients (coronal scoliosis ≥20°, sagittal vertical axis (SVA) ≥5 cm, Pelvic Tilt (PT) ≥25°, or thoracic kyphosis ≥60°) >18 y/o, with Base Line (BL) frailty scores were included. Frailty was scored from 0 to 1 (not frail: <0.3, frail 0.3-0.5, severe frailty >0.5) through the use of ASD-frailty index (FI) which has been validated using the International Spine Study Group (ISSG) ASD database, European Spine Study Group ASD database, and the Scoli-RISK-1 Patient Database. The ISSG is funded through research grants from DePuy Synthes and individual donations and supported the current work. Operative (Op) and Nonoperative (Non-Op) patients were propensity matched. T-tests compared frailty among treatment groups and BL, 1, 2, and ≥3 years. An actuarial Kaplan-Meier survivorship analysis with log-rank (Mantel-Cox) test, adjusting for patients lost to follow-up, determined probability of severe frailty development. Multivariate Cox Regressions gauged the effect of sagittal malalignment, patient and surgical details on severe frailty development.Results
The analysis includes 472 patients (236 Op, 236 Non-Op) selected by propensity score matching from a cohort of 1,172. Demographics and comorbidities were similar between groups (p>.05). Op exhibited decreased frailty at all follow-up intervals compared with BL (BL: 0.22 vs Y1: 0.18; Y2: 0.16; Y3: 0.15, all p<.001). Non-Op displayed similar frailty from BL to 2Y follow up, and increased frailty at 3Y follow up (0.23 vs 0.25, p=.014). Compared with Non-Op, Op had lower frailty at 1Y (0.18 vs 0.24), 2Y (0.16 vs 0.23), and 3Y (0.15 vs 0.25; all p<.001). Cumulative probability of maintaining nonsevere frailty was (Op: 97.7%, Non-Op: 94.5%) at 1Y, (Op: 95.1%, Non-Op: 90.4%) at 2Y, and (Op: 95.1%, Non-Op: 89.1%) at ≥3Y, (p=.018). Among all patients, baseline depression (hazard ratio: 2.688[1.172-6.167], p=.020), Numeric Rating Scale (NRS) back pain scores (HR: 1.247[1.012-1.537], p=.039), and nonoperative treatment (HR: 2.785[1.167-6.659], p=.021) predicted severe frailty development with having a HR>1.0 and p value<.05. Among operative patients, 6-week postoperative residual SVA malalignment (SRS-Schwab SVA+modifier) (HR: 15.034[1.922-116.940], p=.010) predicted severe frailty development indicated by having a HR>1.0 and p value <.05.Conclusions
Non-Op patients were more likely to develop severe frailty, and at a quicker rate. Baseline depression, increased NRS back pain scores, nonoperative treatment, and postoperative sagittal malalignment at 6-week follow-up significantly predicted severe frailty development. Operative intervention and postoperative sagittal balance appear to play significant roles in frailty remediation and maintenance in ASD patients. Frailty is one factor, in a multifactorial conservation, that may be considered when determining operative or nonoperative values for ASD patients. Operating before the onset of severe frailty, may result in a lower complication risk and better long-term clinical outcomes.Item Open Access Redefining cervical spine deformity classification through novel cutoffs: An assessment of the relationship between radiographic parameters and functional neurological outcomes.(Journal of craniovertebral junction & spine, 2021-04) Passias, Peter Gust; Pierce, Katherine E; Brown, Avery E; Bortz, Cole A; Alas, Haddy; Lafage, Renaud; Lafage, Virginie; Line, Breton; Klineberg, Eric O; Burton, Douglas C; Hart, Robert; Daniels, Alan H; Bess, Shay; Diebo, Bassel; Protopsaltis, Themistocles; Eastlack, Robert; Shaffrey, Christopher I; Schwab, Frank J; Smith, Justin S; Ames, Christopher; On Behalf Of The International Spine Study GroupPurpose
The aim is to investigate the relationship between cervical parameters and the modified Japanese Orthopedic Association scale (mJOA).Materials and methods
Surgical adult cervical deformity (CD) patients were included in this retrospective analysis. After determining data followed a parametric distribution through the Shapiro-Wilk Normality (P = 0.15, P > 0.05), Pearson correlations were run for radiographic parameters and mJOA. For significant correlations, logistic regressions were performed to determine a threshold of radiographic measures for which the correlation with mJOA scores was most significant. mJOA score of 14 and <12 reported cut-off values for moderate (M) and severe (S) disability. New modifiers were compared to an existing classification using Spearman's rho and logistic regression analyses to predict outcomes up to 2 years.Results
A total of 123 CD patients were included (60.5 years, 65%F, 29.1 kg/m2). For significant baseline factors from Pearson correlations, the following thresholds were predicted: MGS (M:-12 to-9° and 0°-19°, P = 0.020; S: >19° and <-12°, χ2= 4.291, P = 0.036), TS-CL (M: 26°to 45°, P = 0.201; S: >45°, χ2= 7.8, P = 0.005), CL (M:-21° to 3°, χ2= 8.947, P = 0.004; S: <-21°, χ2= 9.3, P = 0.009), C2-T3 (M: -35° to -25°, χ2= 5.485, P = 0.046; S: <-35°, χ2= 4.1, P = 0.041), C2 Slope (M: 33° to 49°, P = 0.122; S: >49°, χ2= 5.7, P = 0.008), and Frailty (Mild: 0.18-0.27, P = 0.129; Severe: >0.27, P = 0.002). Compared to existing Ames- International Spine Study Group classification, the novel thresholds demonstrated significant predictive value for reoperation and mortality up to 2 years.Conclusions
Collectively, these radiographic values can be utilized in refining existing classifications and developing collective understanding of severity and surgical targets in corrective surgery for adult CD.Item Open Access Risk-benefit assessment of major versus minor osteotomies for flexible and rigid cervical deformity correction.(Journal of craniovertebral junction & spine, 2021-07) Passias, Peter Gust; Passfall, Lara; Horn, Samantha R; Pierce, Katherine E; Lafage, Virginie; Lafage, Renaud; Smith, Justin S; Line, Breton G; Mundis, Gregory M; Eastlack, Robert; Diebo, Bassel G; Protopsaltis, Themistocles S; Kim, Han Jo; Scheer, Justin; Burton, Douglas C; Hart, Robert A; Schwab, Frank J; Bess, Shay; Ames, Christopher P; Shaffrey, Christopher I; International Spine Study GroupIntroduction
Osteotomies are commonly performed to correct sagittal malalignment in cervical deformity (CD). However, the risks and benefits of performing a major osteotomy for cervical deformity correction have been understudied. The objective of this retrospective cohort study was to investigate the risks and benefits of performing a major osteotomy for CD correction.Methods
Patients stratified based on major osteotomy (MAJ) or minor (MIN). Independent t-tests and Chi-squared tests were used to assess differences between MAJ and MIN. A sub-analysis compared patients with flexible versus rigid CL.Results
137 CD patients were included (62 years, 65% F). 19.0% CD patients underwent a MAJ osteotomy. After propensity score matching for cSVA, 52 patients were included. About 19.0% CD patients underwent a MAJ osteotomy. MAJ patients had more minor complications (P = 0.045), despite similar surgical outcomes as MIN. At 3M, MAJ and MIN patients had similar NDI, mJOA, and EQ5D scores, however by 1 year, MAJ patients reached MCID for NDI less than MIN patients (P = 0.003). MAJ patients with rigid deformities had higher rates of complications (79% vs. 29%, P = 0.056) and were less likely to show improvement in NDI at 1 year (0.95 vs. 0.54, P = 0.027). Both groups had similar sagittal realignment at 1 year (all P > 0.05).Conclusions
Cervical deformity patients who underwent a major osteotomy had similar clinical outcomes at 3-months but worse outcomes at 1-year as compared to minor osteotomies, likely due to differences in baseline deformity. Patients with rigid deformities who underwent a major osteotomy had higher complication rates and worse clinical improvement despite similar realignment at 1 year.